Working towards endorsement for the Cambridge Pathway.
Psychology
for Cambridge IGCSE™
COURSEBOOK
Lizzie Gauntlett & Amy Kockott
with Digital access
Starter
pack
Original material © Cambridge University Press & Assessment 2025. This material is not final and is subject to further changes prior to publication.
Working towards endorsement for the Cambridge Pathway.
Dear Cambridge Teacher,
The Cambridge IGCSE™ Psychology Coursebook will publish later this year. Our
Coursebook contains full syllabus coverage, with dozens of engaging activities, psychology
in context and real life features, exciting engagement and support features, formative
assessment opportunities, and much more.
We are working closely with Cambridge Assessment International Education to ensure our
IGCSE™ Psychology (0266) Coursebook is endorsed for student support on publication and
meets all of your needs in this new course.
We have produced this ‘Starter Pack’ to enable you to plan and teach the new
course while we finalise and print the new resource.
The pack contains the following:
Chapter 0: Research Methods
Chapter 1: Memory and Forgetting
Please note that the material included in this Starter Pack is at an advanced draft
stage but may still change between now and publication. Our Coursebook is available in
print and digitally which may vary visually.
We hope you find our resources useful in delivering this exciting course.
Visit our website to view the full series or speak to your local sales representative.
You can find their contact details here:
cambridge.org/education/find-your-sales-consultant
Original material © Cambridge University Press & Assessment 2025. This material is not final and is subject to further changes prior to publication.
Working towards endorsement for the Cambridge Pathway.
Contents
Contents
How to use this series
vi
How to use this book vii
Introduction ix
0
3
3.1 Key concepts
prosocial behaviour
0.1 Experimental methods
3
0.2 Non-experimental methods: observation
17
21
prosocial behaviour
144
3.4 Bandura’s social learning
theory of prosocial behaviour
4
151
Visual Perception
0.4 Non-experimental methods: case studies
26
4.1 Key concepts
163
0.5 Sampling
29
4.2 Gibson’s direct theory of perception
171
0.6 Validity and reliability
33
4.3 Gregory’s constructivist theory
0.7 Ethical guidelines
41
of perception
and procedure
46
0.9 Dealing with data
55
5
Memory and Forgetting
1.1 Key concepts
67
73
1.3 Atkinson and Shiffrin’s Multistore model
(MSM)
184
Motivation and Needs
5.1 Key concepts
194
5.2 Drive reduction theory of motivation
197
5.3 Positive reinforcement in education
203
5.4 Psychodynamic motivation and marketing 209
1.2 Craik and Lockhart’s Levels of Processing
(LoP) model of memory
176
4.4 Visual illusions and culture
0.8 Role of the researcher, materials
2
138
3.3 Social identity theory of
0.3 Non-experimental methods: questionnaires and
1
133
3.2 Biological explanations of
Research Methods
interviews
Prosocial Behaviour
77
5.5 Motivation to exercise 6
Language Development
1.4 Motivated forgetting 84
6.1 Key concepts 1.5 The brain in memory and forgetting
90
6.2 Biological explanation of language
Sleep and Dreams
216
225
acquisition
228
6.3 Learning theory of language development 235
2.1 Key concepts
100
2.2 Restoration theory of sleep
110
2.3 Hobson and McCarley’s activation-
synthesis theory of dreaming
115
2.4 Psychodynamic theory of dreaming
120
6.4 Cognitive theory of language development 239
Glossary
252
Index 256
Acknowledgements
257
v
Original material © Cambridge University Press & Assessment 2025. This material is not final and is subject to further changes prior to publication.
Working towards endorsement for the Cambridge Pathway.
CAMBRIDGE IGCSE™ PSYCHOLOGY: COURSEBOOK
How to use this series
This suite of resources supports students and teachers following the Cambridge IGCSE™
Psychology syllabus (0266) for examination from 2027. All of the components in the series are
designed to work together and help students develop the necessary knowledge and skills for
this subject.
Psychology
for Cambridge IGCSE™
COURSEBOOK
Lizzie Gauntlett & Amy Kockott
with Digital access
The Coursebook provides coverage of the full Cambridge
IGCSE™ Psychology syllabus (0266) for examination from 2027.
Each chapter explains facts and concepts, and uses relevant realworld examples of psychology in action to bring the subject to
life. Together with a focus on active learning opportunities and
assessment of learning, the Coursebook prepares students for
all aspects of their study. At the end of each chapter, practice
questions offer opportunities for students to apply their learning.
Core studies required by the syllabus are provided verbatim in this
Coursebook, so you can be sure that everything you need to know
is included in the ‘Study summary’ feature. Answers can be found
on Cambridge GO via the activation code found on the inside of
the front over.
The Digital Teacher’s Resource contains detailed guidance for
all topics of the syllabus, including common misconceptions
and identifying areas where students might need extra support,
as well as an engaging bank of lesson ideas for each syllabus
topic. Tests and worksheets are provided, ready to hand out
in your lessons. Differentiation is emphasised with advice for
identification of different student needs and suggestions of
appropriate interventions to support and stretch students.
Answers for all components are accessible to teachers on the
Cambridge GO platform.
Psychology
for Cambridge IGCSETM
DIGITAL TEACHER’S RESOURCE
vi
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Working towards endorsement for the Cambridge Pathway.
How to use this book
How to use this book
LEARNING INTENTIONS
TIPS
Each chapter begins with a set of learning
intentions to explain what you will learn in the
chapter.
Tips are provided throughout the Coursebook
to help with your learning. The tips might cover
how to avoid common errors or misconceptions,
advice on essay-writing, statistical data,
evaluation and analysis.
PSYCHOLOGY IN CONTEXT
An opening discussion point at the start of each
chapter that gets you thinking about the content
you are about to study. This feature will relate
theory to the real world and focus on a well-known
study or person, relevant to the chapter. At the
end of this feature, discussion questions allow you
think more deeply about the subject and discuss
with your peers.
KEY TERMS
Key vocabulary is highlighted in the text when it
is first introduced. An accompanying definition
is given in the margin to tell you the meanings
of these words and phrases. You will also find
definitions of these words in the Glossary at the
back of this book.
COMMAND WORDS
Key words that may appear in assessment. Each
command word is highlighted in the text when it
is first introduced. An accompanying definition
is given in the margin to tell you the meaning of
these words.
Questions
Appearing throughout, questions give you a chance to
check that you have understood the topic and check your
level of understanding.
MAKING CONNECTIONS
This feature highlights the links between topics
across psychology, often those within your
Coursebook. It allows you to think about the
connections across psychology to gain a deeper
understanding of the subject. Making connections
also highlights links between psychology and
other subjects you might study.
ACTIVITY
Activities give you an opportunity to check and
develop your understanding throughout the
Coursebook in a more active way.
STUDY SUMMARY
Appearing in only Chapters 1–6, the study
summary focuses on a named study relevant
to the chapter content. It summarises the aim,
participants, procedure, results and conclusion
of the study. These are taken verbatim from the
syllabus, so everything you need to know about
the studies is provided within this feature.
vii
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CAMBRIDGE IGCSE™ PSYCHOLOGY: COURSEBOOK
PSYCHOLOGY IN REAL LIFE
KEY SKILLS EXERCISE
Taking an example from real life, this feature
explains how the topic you’ve been studying
features in real life. Questions at the end of
this feature allow you to engage with the topic
more widely.
At the end of each chapter, this exercise allows
you to develop the key skills. You might find it
helpful to complete these questions to check your
understanding of a chapter before moving on.
REFLECTION
SELF-EVALUATION CHECKLIST
Reflection activities encourage you to look back
on your work and think about your learning.
You will reflect on and assess the approach to
your work.
Each chapter ends with a grid showing statements
that summarise the content covered within the
chapter. You might find it helpful to rate how
confident you feel for each of these statements
when you are revising.
SELF-ASSESSMENT/PEER ASSESSMENT
PRACTICE QUESTIONS
At the end of some activities, this is an
opportunity to assess your own work, or
your peers’ work, and evaluate your level
of understanding in relation to the learning
intentions at the start of the chapter.
Each chapter contains a set of questions
written by the authors that provide practice at
answering different types of tasks relevant to this
syllabus and help you prepare for assessment.
KEY POINTS
Each topic ends with a set of key points
summarising what you have learnt in the topic.
viii
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Working towards endorsement for the Cambridge Pathway.
Introduction
Introduction
Welcome to the first edition of our Cambridge IGCSE™ Psychology Coursebook!
This series provides everything that you need to support your course for Cambridge
IGCSE™ Psychology (0266) and provides full coverage of the syllabus for examination
from 2027.
The chapter order generally follows the same sequences as the topics in the syllabus,
with one exception. We have chosen to open the book with the Research Methods
unit – found at the end of the syllabus – to provide you with everything you need to
work your way through the rest of the course, enabling you to confidently engage with
the more scientific elements of the course from the beginning. You will find that the
skills you have learnt in this chapter will be tested throughout the rest of the book:
don’t hesitate to go back and familiarise yourself with key skills when required.
The various features that you will find in these chapters are explained in the ‘How to
use this book’ pages. It is not enough just to learn words, phrases and dates that you
can repeat in answer to questions; you need to ensure that you really understand each
concept fully.
Trying to answer the questions that you find within each chapter, and at the end of
each chapter, should help you to do this.
As you work through your course, make sure that you keep reflecting on the work
that you did earlier and how it relates to the current topic that you are studying. The
reflection boxes throughout the chapters ask you to think about how you learn, to help
you make the very best use of your time and abilities as your course progresses.
You will also find lots of activities that take you away from the book to more active
forms of learning and application of knowledge. These are also good opportunities to
engage with your peers and reflect on your learning.
Study summaries are taken from the syllabus verbatim. This means you do not need
to do any further research on the studies contained within this resource, as everything
you need to understand and engage with the studies and succeed in your course is
provided here.
We hope you enjoy learning about the human mind. It is an important and relevant
subject that can be challenging, but is absolutely vital to understand and appreciate.
Perhaps you will go on to study Cambridge International AS & A Level Psychology or
beyond, and become one of the psychologists mentioned in the studies in this book!
The Cambridge Team
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Working towards endorsement for the Cambridge Pathway.
Chapter 0
Research
Methods
LEARNING INTENTIONS
In this chapter you will gain knowledge and understanding of, as well as apply, analyse and evaluate:
•
•
•
•
•
•
•
•
•
experimental methods
non-experimental method: observations
non-experimental methods: questionnaires and interviews
non-experimental method: case studies
sampling
validity and reliability
ethical guidelines
role of the researcher, materials and procedure
dealing with data
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CAMBRIDGE IGCSE™ PSYCHOLOGY: COURSEBOOK
PSYCHOLOGY IN CONTEXT
theories or ideas. This is important for applications
in real life, where the results of research are used to
help people, for example to help improve mental
health and wellbeing.
In this way, research findings can help us challenge
beliefs or assumptions we have about humans,
which may be false or even harmful.
Discussion questions
Discuss the following questions in pairs or small
groups. One member of the group could record
your ideas to share with the rest of the class.
1
Figure 0.1: Psychologists use a wide range
of methods and data collection techniques in
their research.
Why do we conduct research in psychology?
As humans, we have ready access to the thoughts,
feelings and behaviour of ourselves and others.
Therefore, you might wonder what the importance
is of undertaking formal research in psychology,
which can be time-consuming and complex!
2
You may have learnt about testing ideas or
conducting investigations in other science
subjects. How might psychology be similar or
different from these subjects?
Think of a problem a psychologist might want
to study, such as how people interact on social
media. Do you think there is more than one
way to investigate this topic? Try to think of as
many different ways as you can.
Planning, completing and analysing research serves
several important purposes. First, it helps us get an
understanding of how people think and feel, and
why they behave the way they do. For example,
researching people’s behaviours in the workplace
can help make the environment or the work they
do safer for everyone.
It can also help us notice patterns of similarities
between people, as well as differences between
them. This might be important for understanding
how children’s thinking processes change as they
get older, and how this can be applied to best
support teaching in schools.
By conducting research, psychologists try to take a
systematic approach to gather evidence by testing
Figure 0.2: By researching the way that children
play, psychologists can better understand how their
thoughts and perceptions develop over time.
2
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0
0.1 Experimental
method
This topic will cover all the key features of the
experimental method. These features are important
aspects of designing an experiment. An experiment
involves manipulating a variable to see how it affects
another variable.
ACTIVITY 0.1
An example of an experiment might be if a
researcher wants to investigate the effect that
noise has on memory recall.
1
Discuss with a partner how the researcher
could carry out this experiment.
2
What might the researcher need to
control to make sure nothing else affects
their experiment?
3
What might the researcher ask the
participants to do in the experiment?
KEY TERM
Experiment: method of investigating the effect
of one variable on another variable, under
controlled conditions.
Research Methods
The features of an experiment
An experiment must be carried out under controlled
conditions. This means that the researcher will do
their best to make sure that nothing else affects their
results. It is important to carry out an experiment under
controlled conditions to be sure that the results show
the effect of what is being manipulated, rather than
anything else.
Experiments can either be carried out in a laboratory
or other highly controlled setting, or they can be
carried out in a real-life setting, such as a school,
park or street. The researcher will decide where to
carry out the experiment based on which they think
will be the most effective setting for what they
are investigating.
An experiment involves participants taking part in
different conditions to see how their results differ.
Applying knowledge of experiments
Although you have not yet learnt all the key features of
an experiment, you have an idea of what an experiment
is so you can start to think about how this could be
applied to different scenarios.
Figure 0.3: An experiment can show the effect
that loud music has on memory recall.
TIP
Critical thinking
An effective way of making sure you understand
a new concept, particularly in research methods,
is to apply it to a novel scenario. This involves
applying what you have learnt to a new situation
and is a great way of helping make sure you
properly understand the concept.
3
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CAMBRIDGE IGCSE™ PSYCHOLOGY: COURSEBOOK
Independent and
dependent variables
The two main variables in an experiment are the
independent variable and the dependent variable.
the researcher are: gender; existence of a condition;
upbringing. These are all differences that may be
investigated to measure the effect they have on a range
of dependent variables but they are not manipulated
or changed by the researcher themselves.
The independent variable is manipulated and the
dependent variable is measured to see what effect the
independent variable has. For example, if you were
interested in the effect of time of day on reaction times,
the independent variable (being manipulated) is the
time of day and the dependent variable (which is being
measured) is reaction time.
Figure 0.5: Age is an example of an independent
variable that is not manipulated by the researcher.
Figure 0.4: Time of day is an example of an
independent variable that can be manipulated
by the researcher.
An independent variable can be manipulated by the
researcher, such as the example shown where the
independent variable is time of day. However, the
independent variable can also simply be observed
as present, meaning that it is just a difference that
occurs between participants. The researcher can then
select participants based on the independent variable
and make comparisons between the results of the
different participants.
For example, if you are investigating the effect of age
on empathy you might want to compare the empathy
level of six-year-olds with the empathy level of 16-yearolds. A researcher cannot manipulate this independent
variable by making people a particular age, but a
researcher can observe the presence of the different
ages and then measure the dependent variable for each
age group to look for differences. Other examples of
independent variables that are not manipulated by
To investigate the effect of an independent variable,
levels (or conditions) are used. The number of levels
show the number of ways the independent variable is
being manipulated. For example, a researcher wants
to study the effect of temperature on problem-solving
skills, where participants are asked to complete a
logic puzzle as quickly as possible. In one level, the
participant is in a very hot room; in one level, the
participant is in an average temperature room; in
one level, the participant is in a very cold room. The
changes in the dependent variable for each level of the
independent variable are compared to see what effect
the independent variable has. In this case, the study will
show us whether problem-solving is affected by hot or
cold temperatures.
KEY TERMS
Independent variable: the variable that is
manipulated; may have two or more conditions
or levels.
Dependent variable: a variable that is measured.
4
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0
Research Methods
There are lots of different ways in which the dependent
variable can be measured:
•
•
•
Experimental tests or tasks: participants are
exposed to a level of the independent variable and
they need to complete a particular task or test to
measure the effect of the independent variable.
Examples of experimental tests or tasks include:
mathematical tests, memory recall tasks, or
computer tasks to test things such as reaction time.
Observation: this involves watching participants’
behaviour when exposed to a particular level of the
independent variable and recording what is seen,
then analysing the observations (see Topic 0.2 for
more detail).
Questionnaires and interviews: questionnaires
involve a set of written questions for the participant
to answer. These answers would be compared
between different levels of the independent variable.
Interviews also involve asking the participant
questions, although the questions are asked face-toface in an interview (see Topic 0.3 for more detail).
Figure 0.6: An experiment can show if owning a pet
impacts anxiety levels.
ACTIVITY 0.2
For each example, name the independent
variable and the dependent variable:
Applying knowledge of independent
and dependent variables
1
The effect of exercise on stress.
2
The effect of age on fitness.
Now you have learnt what an independent variable and
a dependent variable is, you can apply them to a range
of different scenarios.
3
Whether men have higher stress levels
than women.
4
The effect of sunshine on happiness.
5
Whether screen time affects
children’s intelligence.
6
Whether confidence affects achievement.
7
How memory is affected by sleep.
Anything that could be investigated will have an
independent variable that is manipulated and a
dependent variable that is measured. For example, to
investigate the effect of owning pets on anxiety, the
independent variable is whether someone has pets and
the dependent variable is anxiety level. This allows for
comparison of the anxiety levels of participants with
pets to the anxiety levels of people without pets. If the
anxiety levels for participants with pets is lower than the
anxiety levels for those without, it could be concluded
that owning pets has a positive impact on anxiety levels.
If there is no significant difference between anxiety
levels of participants with pets compared to anxiety
levels of participants without pets, it could be concluded
that owning pets has no significant effect on anxiety. If
the anxiety level of participants with pets is higher than
the anxiety levels of participants without pets, it could
be concluded that owning pets has a negative effect on
anxiety levels.
Operationalising variables
For an effective experiment to be carried out, both the
independent variable and the dependent variable need to
be operationalised. This means that each variable must
be defined in a specific way so that it can be accurately
measured or observed.
KEY TERM
Operationalised: defining a variable or
behavioural category so it can be accurately
measured or observed.
5
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CAMBRIDGE IGCSE™ PSYCHOLOGY: COURSEBOOK
Operationalising the independent variable and dependent
variable allows for a more specific description of what
is being investigated. For example, if a researcher wants
to investigate the effect of hard work on achievement,
that is a very broad and vague area to investigate. It
does not tell us anything about the experiment itself.
‘Hard work’ could be interpreted in many different
ways and ‘achievement’ could be measured in many
different ways. If a researcher says they will investigate
this using ‘revision time’ as the independent variable and
‘achievement in psychology course’ as the dependent
variable, this would give a much clearer idea of what the
researcher was going to investigate.
However, the same investigation could be approached
in a different way by using ‘amount of swimming’ as my
independent variable and ‘achievement in a swimming
race’ as my dependent variable. Both examples investigate
the effect of hard work on achievement because both
independent variables are ways of changing the level of
‘hard work’ and both dependent variables are ways of
measuring ‘achievement’ but in very different ways.
These examples have made the experiment clearer; the
description of the independent variable and dependent
variable in each example gives a reasonable idea of how
the variables are being defined. However, the variables
are not yet operationalised because we have not
explained how the variables will be measured. We need
to explain a way that each variable can be measured in
an objective way, removing any bias or interpretation
from the researcher. Some variables are fairly obvious
and easy to operationalise, whereas other variables may
have many different options, and may require some
thoughtful or creative ways of measuring.
Let’s operationalise the examples shown previously.
Independent/
dependent
variable
Variable
Operationalised
Independent
variable
Revision time
Number of hours of
revision per week
Dependent
variable
Achievement
in psychology
course
Score on
psychology end of
year assessment
Independent
variable
Amount of
swimming
Number of lengths
swum per week
Dependent
variable
Achievement in
swimming race
Finishing position
in swimming race
Operationalising the variables turns them into specific
and measurable variables rather than a vague idea.
Operationalised variables should give a clear and
accurate understanding of what is being tested and
what is being measured.
Figure 0.7: Number of hours of revision per week
is an example of an operationalised independent
variable. It is a much more specific, and therefore
more useful, way measuring ‘hard work’.
Applying knowledge of
operationalising variables
Knowing how to operationalise variables is essential
for carrying out any experiment. As long as you know
that operationalising means making the variables
specific and measurable, you can do this for any
variable. For example, to investigate the effect of owning
pets on anxiety, the independent variable is whether
someone has pets or not and the dependent variable
is anxiety level. The independent variable could be
operationalised to ‘the number of pets owned’ or ‘owns
a pet or does not own a pet’. The dependent variable
could be operationalised to ‘anxiety score on a scale
of 1–10 with 1 being not at all anxious and 10 being
extremely anxious’.
Table 0.1: Examples of operationalised independent
and dependent variables.
6
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0
ACTIVITY 0.3
For each example, operationalise the
independent variable and dependent variable
that you suggested in Activity 0.2.
1
The effect of exercise on stress.
2
The effect of age on fitness.
3
Whether men have higher stress levels
than women.
4
The effect of sunshine on happiness.
5
Whether screen time affects children’s
intelligence.
6
Whether confidence affects achievement.
7
How memory is affected by sleep.
PEER ASSESSMENT
When you have completed the activity, swap your
work with another student. Check that you agree
with their way of operationalising each variable:
is it specific and measurable? If there are any you
disagree with, discuss them with your partner and
come up with an improvement together.
Next, as a pair, discuss any differences in your
operationalising, and discuss how these different
approaches would lead to different experiments.
Working together, is it possible to come up with
another way of operationalising each variable?
Research Methods
and independent measures. Repeated measures refers
to a type of experimental design where participants
experience all the levels of the independent variable.
Independent measures refers to a type of experimental
design where participants experience only one of the
levels of the independent variable.
Repeated measures
With repeated measures, the same participants take part
in each condition of an experiment. The effect on the
dependent variable is measured for each participant in
each condition. The results for each participant are then
compared between levels to look for differences.
Imagine you are investigating the effect of imagery
on happiness using a repeated measures experimental
design. The independent variable is ‘imagery’ which
is operationalised as ‘green field’ or ‘city street’.
The dependent variable is ‘happiness’, which is
operationalised as ‘happiness on a scale of 1–10 where
1 is very unhappy and 10 is very happy’. For repeated
measures, all participants experience all levels of the
independent variable so in this case every participant:
•
•
looks at an image of a green field then scores
themselves on a scale of 1–10 for happiness
looks at an image of a city street then scores
themselves on a scale of 1–10 for happiness.
For each participant, their happiness score after looking
at a green field is compared to their happiness score
after looking at a city street.
KEY TERMS
Experimental design
As we know, the independent variable has levels
or conditions. To test the effect of the independent
variable, participants are exposed to different levels
and the effect on the dependent variable is compared.
Assigning participants to different conditions or levels
in an experiment is known as experimental design.
Sometimes all participants are exposed to each level
of the independent variable and sometimes each
participant is only exposed to one level. Two different
types of experimental design are repeated measures
Experimental design: a way of assigning
participants to different conditions or levels in
an experiment.
Repeated measures: same participants take part
in each condition of an experiment; participants
experience all the levels of the independent
variable.
Independent measures: different participants
take part in each condition of an experiment;
participants experience only one of the levels
of the independent variable.
7
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CAMBRIDGE IGCSE™ PSYCHOLOGY: COURSEBOOK
Condition:
listen to pop
music
A
B
C
Condition:
listen to
classical music
A
B
C
Figure 0.8: Repeated measures involves each
participant taking part in each condition of
an experiment.
A problem with repeated measures is that the order the
participants are exposed to the levels of the independent
variable could affect the results. For example, if
participants are asked to complete a puzzle in loud
noise, then in silence, the participants may get better at
the puzzle in the second condition because they have
already practised it. This could affect the validity of the
results because an improvement in the puzzle may not
be because of the change from loud noise to silence but
instead due to the order of the levels.
A similar issue is that participants may work out the
aim of the study after completing more than one
condition. This could affect their performance as they
may change their behaviour to try to fit with what they
think the researcher is looking for. These issues can be
resolved by counterbalancing. Counterbalancing involves
changing the order in which participants experience
the different conditions to reduce the impact of other
variables (such as practice, boredom, time of day).
With counterbalancing, half of the participants would
complete condition A, followed by condition B, and the
other half of participants would complete condition
B, followed by condition A. This means that any order
effect is removed as it balances itself out. In the previous
example, half of the participants would complete the
puzzle in loud noise followed by silence and the other
half of the participants would complete the puzzle in
silence followed by loud noise.
KEY TERM
Counterbalancing: changing the order in which
participants experience the different conditions,
to reduce the impact of extraneous variables in
an experiment.
Independent measures
With independent measures, different participants take
part in each condition of an experiment. The effect on
the dependent variable is measured for each level of the
independent variable and the results between each group
are compared.
Imagine you are investigating the effect of music genre
on happiness, by using an independent measures design.
The independent variable is ‘music genre’, which is
operationalised as ‘pop or classical’. The dependent
variable is ‘happiness’, which is operationalised
as ‘happiness on a scale of 1–10 where 1 is very
unhappy and 10 is very happy’. For independent
measures, participants only experience one level of
the independent variable so in this case half of the
participants listen to pop music then score themselves
on a scale of 1–10 for happiness and the other half
of participants listen to classical music then score
themselves on a scale of 1–10 for happiness. Happiness
scores after listening to pop music are then compared
to happiness scores after listening to classical music.
Condition:
listen to pop
music
A
B
C
Condition:
listen to
classical music
A
D
E
F
Figure 0.9: Independent measures involves each
participant only experiencing one condition in an
experiment.
One problem with independent measures is that
individual differences between participants could
affect the results. If one group of participants is in
one condition and another group of participants is
in another condition, any differences between the
results could be due to the independent variable
but they could also be due to differences between
the participants.
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For example, if you are measuring the effect of noise
on puzzle completion, one group of participants
completes the puzzle in silence and another group
completes the puzzle in loud noise. If the puzzle is
completed better in silence than in loud noise this
could be because of the change in noise level. However,
the difference could also be due to the difference in
the participants in each group. One group may have
participants who are particularly good at puzzles, or
who are used to concentrating in loud conditions,
so this could affect the results. Another issue with
using different participants in each group is that the
researcher could select participants for each condition
deliberately to try to achieve their hypothesis: this is
called researcher bias. For example, the researcher
may choose younger participants to complete the
silent condition and older participants to complete the
loud noise condition. Younger people may, in general,
be better at completing puzzles than older people,
so assigning the participants in this way may bias or
influence the results.
Random allocation is an important way of removing
bias in research. Random allocation means assigning
participants to different conditions in an experiment
so that each participant has an equal chance of being
assigned to any particular condition. This reduces the
issue of individual differences and removes researcher
bias because participants cannot be assigned to a
condition to suit the needs of the researcher.
With random allocation the researcher may put all
the participants’ names into a bowl and pull names
out one by one to randomly allocate the participants
to each condition. This ensures that each participant
has an equal chance of being placed in each condition.
A random number generator could also be used. Here,
each participant is assigned a number and a computer
program randomly generates numbers to assign the
participants to each condition.
KEY TERM
Random allocation: assignment of participants
to different conditions in an experiment, so that
each participant has an equal chance of being
assigned to any particular condition.
Research Methods
Figure 0.10: Random allocation can be achieved by
putting all participant names in a bowl and pulling
them out one by one.
Applying knowledge of
experimental design
You now know what experimental design means, and
have learnt the two main types of experimental design:
repeated measures and independent measures. When a
researcher is designing an experiment, they will decide
which experimental design to use based on which they
feel will work best in their experiment.
ACTIVITY 0.4
Imagine you are planning experimental designs to
measure the effect of the independent variables
on the dependent variables from Activities 0.2 and
0.3. Imagine you have recruited 60 participants
each time. For each example, explain how
you would apply either repeated measures or
independent measures. Remember to consider
counterbalancing and random allocation:
1
The effect of exercise on stress.
2
The effect of age on fitness.
3
Whether men have higher stress levels
than women.
4
The effect of sunshine on happiness.
5
Whether screen time affects
children’s intelligence.
6
Whether confidence affects achievement.
7
How memory is affected by sleep.
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Experimental conditions
As we have already learnt, levels (or conditions) are
used to investigate the effect of an independent variable.
The number of levels show the number of ways the
independent variable is manipulated. There may be
only two levels or there could be several. Each level
of the independent variable that is manipulated in an
experiment is called an experimental condition. This
means that participants are assigned to an experimental
condition to be exposed to one level of the independent
variable and the effect on the dependent variable
is measured.
Consider the following two scenarios:
•
•
If you have 60 participants and you have two levels
of the independent variable, you will have two
experimental conditions. Either repeated measures
or independent measures can be used. For repeated
measures, you can assign all 60 participants to both
experimental conditions. For independent measures,
you can assign 30 participants to one experimental
condition and the other 30 participants to the other
experimental condition.
If you have 60 participants and you decide to have
five levels of the independent variable, you will
have five experimental conditions. For repeated
measures, you can assign all 60 participants
to all five of the experimental conditions. For
independent measures, you can assign 12
participants to the first experimental condition,
12 to the next experimental condition and so on
until there are 12 different participants assigned
to each experimental condition.
Applying experimental conditions
Applying knowledge of experimental conditions
requires you to think about the number of levels of the
independent variable you want to use, and therefore the
number of experimental conditions you have.
For example, if you are testing the effect of time of
day on tiredness you might have two levels of your
independent variable, such as 10:00 and 16:00. In this
case the two experimental conditions would be ‘10:00’
and ‘16:00’. You would ask participants to complete
a scale of 1-10, where 1 is not being tired at all and
10 being extremely tired, to say how tired they feel
at 10:00 and at 16:00 and you would then compare the
results for each experimental condition. Alternatively,
you might decide to have five levels of your independent
variable, such as 10:00, 13:00, 16:00, 19:00 and
22:00. Here, each of the five times of day would be
an experimental condition, so there would be five
experimental conditions in total. In this case, you would
ask participants to complete the scale to say how tired
they feel at 10:00, 13:00, 16:00, 19:00 and 22:00 and then
compare the results.
Experimental groups
and control groups
Participants who take part in one or more experimental
conditions are called experimental groups. The
number of experimental conditions an experiment
has will determine the number of experimental
groups that are needed. If an experiment has three
levels of the independent variable this means there
are three experimental conditions. This will require
three experimental groups if an independent groups
experimental design is used, or one experimental group
if a repeated measures experimental design is used. For
example, if the researcher is measuring the effect of
relaxation on sleep quality they might choose to have
three levels of the independent variable: meditation;
listening to an audio book; breathing exercises. There
are three experimental groups so that one experimental
group can do meditation before bed; one experimental
group can listen to an audio book before bed; and one
experimental group can do breathing exercises before
bed. The dependent variable, sleep quality, can be
measured using a sleep tracker. The sleep quality of
each experimental group can be compared to see if
there is a difference.
KEY TERMS
Experimental conditions: levels of the
independent variable that are manipulated
in an experiment.
Experimental groups: participants who
experience the experimental condition(s).
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Research Methods
of sleep between the control group and the experimental
groups. This would tell you whether relaxation affects
sleep quality at all, as well as which (if any) relaxation
technique has the greatest impact.
Figure 0.11: Listening to an audio book might be
one experimental condition involved in measuring
the effect of relaxation on sleep quality.
For a researcher to determine whether the independent
variable has an effect on the dependent variable some
sort of comparison must be made. This can either
be a comparison between two or more experimental
groups (each one exposed to one level of the
independent variable) or a comparison between one
or more experimental groups and a control group.
A control group is a group of participants who do not
experience the experimental condition and are used
as a comparison. This means that, rather than just
comparing different levels of an independent variable
to each other, the effect of the independent variable on
participants who are not exposed to any changes can
be compared.
In this example, investigating the effect of relaxation
on sleep quality, the results would show us if any of
the three relaxation techniques worked better than the
others. However, the only way to tell if the independent
variable has any effect on the dependent variable is to
compare an experimental group (who are exposed to
the independent variable) to a control group (who are
not exposed to anything). To truly measure the effect
of relaxation on sleep quality it would be necessary
to compare the quality of sleep of participants who
use a relaxation technique to the quality of sleep of
participants who do not use a relaxation technique.
For this example, you would have the three experimental
groups as described before (one group each for
meditation, listening to an audio book, and breathing
techniques) and a control group of participants who do
not use any relaxation techniques. You would then use
the data from the sleep trackers to compare the quality
Figure 0.12: Research measuring the effects of
relaxation techniques on sleep can provide useful
information about how best to get a good night of sleep.
A simpler experiment could involve just one
experimental group and a control group. For example,
if you were investigating whether exercise affected
concentration level you could have an experimental
group do a twenty-minute workout class then ask them
to complete a complex puzzle. A control group would be
asked to complete the complex puzzle without carrying
out any exercise beforehand. If the experimental group
completed the puzzle more quickly than the control
group this would suggest that exercise has a positive
effect on concentration. If there was no significant
difference in the speed of the puzzle completion
between the experimental group and control group this
would suggest that exercise has no significant effect on
concentration. If the control group completed the puzzle
faster than the experimental group this would suggest
that exercise has a negative effect on concentration.
KEY TERM
Control group: participants who do not
experience the experimental condition(s) and
are used as a comparison group.
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TIP
Knowledge
When learning lots of new key terms and
definitions try using different coloured pens for
different key terms, or draw different coloured
or shaped boxes around each one. This will
help you to match up the key terms with the
correct definitions.
Applying experimental groups
and control groups
Knowledge of experimental groups and control groups
can be applied to a range of different scenarios in simple
or complex ways. The simplest approach is to use one
experimental group and a control group and compare
the effects on the dependent variable. This approach
allows you to determine whether the independent
variable has an effect on the dependent variable,
however, it does not provide a lot of information.
A more complex approach would be to use several
experimental groups and a control group and make
comparisons between all the groups. This would allow
you to determine not only whether the independent
variable has an effect on the dependent variable, but
also which level of the independent variable makes the
most impact.
For example, let’s apply your knowledge of experimental
groups and control groups to an experiment into the
effects of reading on happiness. You could have one
experimental group, who read a book for half an hour
and then complete a questionnaire about their happiness
level. These results could be compared to a control
group, who just complete a questionnaire about their
happiness level without reading first. If the happiness
level of the experimental group is higher than the
happiness level of the control group this tells you that
reading has a positive effect on happiness. However,
this does not tell you very much about whether the
type of material you read affects happiness. To find this
out you could have several experimental groups. Each
experimental group reads a different genre of book
(such as adventure, non-fiction, thriller, mystery) before
completing the happiness questionnaire. The happiness
level of each group is then compared to the happiness
level of the control group who have not read anything.
This would show us whether a particular genre of book
has more of an influence on happiness level.
Figure 0.13: Experimental conditions could involve
participants reading different genres of books to see
the effect on happiness level.
Extraneous variables
and control
An extraneous variable is a variable, other than the
independent variable, that can have an impact on the
dependent variable in an experiment. We know that the aim
of an experiment is to test the effect that the independent
variable has on the dependent variable. We want to make
sure that nothing else has an effect on the dependent
variable so that we can be sure that any changes we see in
the dependent variable are due solely to the independent
variable. A researcher therefore needs to control these
extraneous variables as much as possible. Control refers
to any steps taken by the researcher to reduce or keep
the impact of extraneous variables constant. The more
control the researcher has on the experiment the more
confident they can be that any changes seen in the
dependent variable are due to the independent variable. The
first step in minimising the effect of extraneous variables
on an experiment is to identify any extraneous variables
that may be relevant. Once identified, the researcher can
make steps to control for the extraneous variables.
KEY TERMS
Extraneous variable: a variable, other than the
independent variable, that can have an impact on
the dependent variable in an experiment.
Control: step(s) taken by researcher to reduce or
keep the impact of extraneous variable(s) constant.
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There are many examples of extraneous variables, some
of which apply to the participants and some of which
apply to the experiment.
Extraneous variables related
to participants
Examples of extraneous variables related to the
participants are as follows:
•
•
•
•
•
age of the participant
gender of the participant
any conditions or disorders of the participant
upbringing of the participant
any other relevant characteristics of the participant.
Research Methods
Once an extraneous variable related to the participants
is identified, it can be controlled by either:
•
•
only using participants who share the same
characteristic, or
randomly assigning participants to
experimental groups.
In the example of age as an extraneous variable affecting
reading speed, you could either only use one age group
(either just five-year-olds, or just 11-year-olds), or you
could use children from a range of ages but randomly
assign them to each experimental group. This would
ensure that each participant has an equal chance of
being in each experimental group and therefore that the
ages are spread across experimental groups. In this case
this would mean that, even though 11-year-olds would
read faster than five-year-olds, the impact of age is likely
to be spread across the experimental groups so it would
affect each experimental group in the same way and
therefore have less of an impact on the results.
Extraneous variables related
to the experiment
Examples of extraneous variables related to
the experiment are as follows:
Figure 0.14: Age and gender are two examples of
extraneous variables.
Before extraneous variables related to participants can
be controlled, they must first be identified. Sometimes
this is obvious and sometimes it is unclear. For example,
if you are conducting an experiment into the effect of
time of day on reading speed it is fairly obvious that
age will be an extraneous variable. If you use some
participants who are five and some participants who
are 11, it is fair to assume that the 11-year-olds will be
able to read faster, on average, than the five-year-olds,
regardless of the time of day. However, gender, for
example, may or may not be an extraneous variable: it
is unclear. Further research may be needed to identify
whether there is an overall significant difference in
reading speed between girls and boys.
•
•
•
•
•
time of day
background noise / temperature / distraction
the type or difficulty of the experimental task
the instructions given to the participant
the behaviour of the researcher.
Figure 0.15: A researcher may treat participants
differently and affect participants’ responses.
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As with extraneous variables that apply to participants,
the first step here is to identify any extraneous variables
so that they can be controlled. Some of these are fairly
standard for most experiments, so a standardised
procedure is used to account for these. A standardised
procedure means keeping as many aspects of the
experiment as possible the same for each participant, to
make sure that no differences are extraneous variables
that impact the results. For example, researchers make
sure that they:
•
•
•
•
give the exact same instructions to each participant
speak to each participant in the same way
give the same amount of time to each participant
use the same task (or questionnaire or interview) to
measure the dependent variable for all participants.
This will ensure that any differences found are due to the
changes in the independent variable, not due to changes
in the way the dependent variable is measured.
For example, if a maths test is used to measure
mathematical ability in different conditions, it is essential
that the same maths test is used for each experimental
group. If different tests were used, there would be no
way to know that any differences in results were due to
changes in the independent variable and not due to one
test being harder than the other. When using repeated
measures, it may not always be possible to measure the
dependent variable in the exact same way each time
because the same participants will be exposed to each
condition. For example, if they were given the same
maths tests over five conditions participants will probably
improve each time as they will become more familiar with
the questions. In this case it would be necessary to use
different but comparable tests that are the same level of
difficulty and have the same number of questions.
It may not always be possible to control for extraneous
variables by making them all the same for all
participants but, if this is the case, it is important
to make sure that any impact is constant across
experimental conditions. For example, time of day
is a potential extraneous variable that may affect
performance in a range of tasks. It may not be practical
to have all participants complete the task at the exact
same time of day. The effect of time of day could be
minimised by having participants complete the task at
as similar times of the day as possible. For example,
some complete the task at 10:00 and others at 11:00.
It is unlikely that this hour difference will have a great
impact on results. Another way would be to have all
participants complete their task at 10:00 on different
days of the week, if time and resources allow. A third
way of dealing with this extraneous variable is to ensure
that its impact is constant across all experimental
conditions. If participants must complete the task
at different times of the day the researcher could
ensure that the same number of participants in each
experimental condition complete the task at each time
of the day. This means that, if the task completion is
easier at one time of the day and harder at other times
of the day, the impact of time of day would at least
affect each experimental condition equally so the effect
on results would be minimal.
MAKING CONNECTIONS
As you learn named studies throughout the
course consider what the independent and
dependent variables are. Consider if there
are any extraneous variables, and what the
researcher may have done to control for these.
Applying extraneous variables
and control
Figure 0.16: When tests are used to measure ability
in research, it is important to consider and control
extraneous variables as far as possible.
Now you know what extraneous variables are, and how
to control for them, you can apply this knowledge to
different scenarios. For example, imagine you are trying
to investigate the effect of temperature on memory recall.
Memory recall can be measured by asking participants
to recall as many words as possible from a list of words
read aloud to them. There could be two experimental
groups and one control group. Participants in one
experimental group can be given the memory recall
task in a very hot room, while the other experimental
group can be given the memory recall task in a very cold
room. Participants in the control group can be given
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the memory recall task in an ambient, average room
temperature. By comparing the number of words recalled
in each group, you can determine whether temperature
has an effect on memory recall, and how the effect of
high and low temperatures compare.
Research Methods
CONTINUED
3
the effect of number of siblings on
confidence
4
the effect of fizzy drinks on reaction time
5
the effect of gender on optimism
6
the effect of age on memory.
ACTIVITY 0.6
Figure 0.17: Extremes of temperature may have an
effect on memory recall.
For example, if more words were recalled in the control
group than in either of the experimental groups, you
could conclude that extremes of temperature have a
negative effect on memory recall. However, if each
group of participants was given a different list of words
to recall, this may affect the results, so it would be
considered an extraneous variable. If participants in the
control group were given a list of simple, short words to
recall, and those in the experimental groups were given
a list of long or complex words to recall, this could
account for the better recall in the control group, and
temperature may not have an effect at all. You will need
to control for this extraneous variable by making sure
that participants in each group are given the same word
lists to recall. This removes the effect of the extraneous
variable and makes it more likely that any differences
in the recall of each group is due to the temperature
difference between the groups rather than anything else.
Design your own experiment. Now you
have learnt about all the key features of the
experimental method you can design your
own. Choose something within psychology that
interests you and plan how you would carry out
an experiment. If you are struggling to think of an
idea then use one of the ideas from this section.
Try to complete this activity as much as possible
without using the textbook, but check back on
any aspects you are less confident on.
When you write out your plan, make sure you
include the following headings:
•
•
•
•
•
•
•
•
independent variable: operationalised
dependent variable: operationalised
experimental design (either repeated
measures or independent measures)
experimental conditions
experimental groups
control group
extraneous variables
control.
REFLECTION
ACTIVITY 0.5
Work in pairs. For each of the examples, identify
one extraneous variable that could affect the
results, and suggest one way this extraneous
variable could be controlled for:
1
the effect of singing on mood
2
the effect of healthy eating on mental
wellbeing
Think about your approach to this activity.
How did you feel about giving it a go without
the textbook first? If you did not try without
the textbook, why was that? Was it a lack of
confidence? Next time, have a go at an activity
or question without the textbook first to see
how you get on. There is no harm in trying by
yourself first of all and then using the textbook
to check or help complete the work.
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Questions
COMMAND WORDS
Define what is meant by the following terms:
1
2
Define: give precise meaning.
a
independent variable
b
dependent variable
c
extraneous variable
Explain: set out purposes or reasons/make the
relationships between things clear/say why and/
or how and support with relevant evidence.
d
control.
State: express in clear terms.
A researcher has 50 participants and there are
two conditions in her experiment (condition A
and condition B).
Explain how the researcher would design her
experiment using:
3
a
repeated measures
b
independent measures.
Identify: name/select/recognise.
Suggest: apply knowledge and understanding
to situations where there is a range of valid
responses to make proposals/put forward
considerations.
An experiment is being carried out to measure
the effect of healthy eating on energy levels.
For this experiment:
a
State the independent variable and dependent
variable. Operationalise each variable.
b
I dentify one extraneous variable and suggest
how it could be controlled.
KEY POINTS
•
•
•
•
•
An experiment must be carried out in
controlled conditions. Participants are
exposed to different conditions and results
are compared.
An independent variable is a variable that
is manipulated. Different levels (conditions)
represent the different variations of the
independent variable.
A dependent variable is a variable that
is measured to see the effect of the
independent variable. It can be measured
using experimental tests or tasks, observation,
questionnaires and interviews.
The independent variable and dependent
variable need to be operationalised. This
means they need to be defined so that they
can be accurately measured or observed.
The experimental design refers to how the
participants are assigned to conditions.
Two experimental designs are:
•
•
•
•
•
Repeated measures: the same
participants take part in all conditions
of the experiment and their results are
compared.
• Independent measures: different
participants take part in different
conditions of the experiment and their
results are compared.
Experimental conditions are the levels of the
independent variable.
Experimental groups are the participants that
take part in the experimental conditions.
The control group are the participants who do
not experience the experimental conditions
and act as a comparison.
An extraneous variable is any variable other
than the independent variable that may affect
the dependent variable in an experiment.
These must be controlled to minimise the
effect they have on the experiment.
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Research Methods
0.2 Non-experimental
methods: observation
Structured and
unstructured observation
The key features of any observation are that the
researcher must first watch the participants and then
record the participants’ behaviour. Although the term
‘watch’ is used here, the researcher will also use their
other senses to collect data. For example, researchers
may choose to listen and record the words spoken by
participants during an observation.
In some cases, the researcher may choose to observe
participants in a way that has no specific focus. This
means they will write down a whole range of possible
behaviours that the participant shows during the period
of time they are being observed. This is known as an
unstructured observation. Psychologists sometimes
choose to use an unstructured observation early in their
research or when planning or designing how to carry
out their research. For example, using an unstructured
observation gives them the opportunity to consider
which behaviours are most important to their aim.
Observation is often used as a technique to collect data
about variables. This means it can be used within other
research methods. For example, observation might be the
technique that a researcher uses to measure the dependent
variable in their experiment. However, observations
are sometimes used as a research method on their own,
without comparing different conditions, and for this
reason observation can be considered non-experimental.
TIP
Research methods
Research methods in psychology can often
be best understood when you are actively
learning and practising some of the techniques
yourself. Remember, psychologists follow strict
ethical guidelines to keep themselves and their
participants safe. There are some suggestions
in this topic for how you can carry out small
observations which bring the techniques to life,
without risk of harm to yourself and others, but
always ask a teacher if you are unsure.
A structured observation takes place when a fixed set
of behaviours is considered. Instead of recording
everything the participant does, the researcher has
already formed an idea of the key behaviours that are
relevant to the study. To limit the number of behaviours
they are observing and recording, the researcher must
define behavioural categories.
For example, if a researcher was studying how people
communicate with team members in sports activities,
they might include some behavioural categories.
These might be: encouragement to others, expressing
frustration at oneself, celebration and so on. Each one
of these specific behaviours is recorded as a separate
category by the researcher during the observation.
KEY TERMS
Observation: method of collecting data by
watching participants.
Unstructured observation: observing a
complete range of possible behaviours that the
researcher does not select in advance.
Structured observation: observing a fixed set of
behaviours that the researcher selects in advance.
Behavioural categories: specific activities
recorded in a structured observation.
Figure 0.18: Observation can be used to collect
data on participants across a range of natural or
artificial settings.
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Applying knowledge of observations
To apply your knowledge of this non-experimental
method, you will need to recognise the features of
an observation. This also means understanding the
choices psychologists make about using different
types of observation. Use Activity 0.6 to explore how
you can apply your knowledge from this chapter to
a novel scenario.
MAKING CONNECTIONS
The named study schema and language (Hewitt)
(see Chapter 6: Language Development)
uses observation to collect data about young
children. Throughout this chapter, you will learn
about a number of other non-experimental and
experimental research methods.
Consider why observation might be a
researcher’s preferred method or data collection
technique for studying the behaviour of young
children. Why might this method be more
practical than using other methods to study
this population?
Behavioural categories
Behavioural categories used in structured observations
must be operationalised to support reliability in
collecting data. For example, if a researcher (or
‘observer’ in this case) wanted to use a structured
observation to observe children’s reactions to being
shown a new toy, they would consider the categories
they would use to measure the reaction. If they wanted
to include positive, negative or neutral responses, each
of these would need to be defined. The behavioural
category of positive response might be operationalised
as ‘laughing, smiling or reaching for the toy’, and
negative response might be defined as ‘frowning,
crying, looking or moving away from the toy’ (see
Figure 0.19)
Behavioural categories
Positive Negative
Neutral
Operationalised Smiling
Frowning Looking
as…
at toy
at toy
away from
toy
Laughing Crying at No change
at toy
toy
to facial
expression
Reaching Moving
for toy
away
from toy
No
change to
vocalisations
Figure 0.19: In structured observations, behavioural
categories must be operationalised to ensure the
data collected is reliable.
It is important to note that behavioural categories
can only include actions or speech that can be seen or
heard by another person. In an observation, you cannot
‘infer’ or interpret what a person is thinking or feeling.
In the previous example, the behaviour of smiling can
be observed, but ‘feeling excited about the toy’ cannot.
This helps make observations objective, an idea that is
explained further in Topic 0.7.
Once the observer has operationalised their behavioural
categories, the observed behaviours need to be recorded
in a meaningful way. For a structured observation it is
typical to use a tally chart or checklist of behaviours.
Each time the observer sees a certain behaviour
being performed, they indicate this by checking it off
against their fixed list of behaviours (Figure 0.20). If
the researcher is interested in noting how often the
participant performs a certain behaviour, they can add
a ‘tally’ mark by each behaviour to record the number
of times it was observed (Figure 0.21).
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Research Methods
to categorise behaviour. For example, if you were
observing helpfulness in young children, you might want
to record data on two behavioural categories: verbal acts
of helping and physical acts of helping. For both these
categories, you need to decide how to operationalise
each. The more clearly you can define or operationalise
the categories, the more likely it is you can apply this in
your observation in a consistent way.
Figure 0.20: Observers use checklists for observed
behaviours in structured observations.
In this example, you might operationalise physical acts
of helping as: holding a door open for another person,
moving oneself or one’s possessions out of somebody’s
way, picking up items for another, and so on. The more
detailed and clearly operationalised the category is, the
better data you will be able to record on your participants.
If behavioural categories are not operationalised clearly,
it might be difficult to apply them consistently to each
participant, or even to the same participant during
the course of observation. To see how to apply your
knowledge of operationalising behavioural categories
to novel scenarios, complete Activity 0.7.
ACTIVITY 0.7
Figure 0.21: Observers use tally charts for observed
behaviours in structured observations.
In some studies, more than one researcher will
undertake the observation. Therefore, it is important
to clearly operationalise behavioural categories during
observation to ensure that the behaviours that the
researcher records are reliable (they are consistent).
Video recording is helpful as it enables researchers to
rewatch and note behaviours they may have missed
during a live observation. It also allows for multiple
researchers to observe the participants’ behaviour. You
will learn more about reliability and specifically, interobserver reliability in Topic 0.7.
Find an animal to watch, such as a pet, an animal
you can safely observe outside, or a short video
of an animal. For one minute (you might want to
use a timer if you have one), try to record all its
behaviours. Write these all down in order.
1
What were the challenges of this
unstructured observation?
2
Using your notes from this observation, create
a checklist of behaviours that could be used for
a structured observation of the same animal.
Applying knowledge of
operationalisation of
behavioural categories
To apply your knowledge of operationalisation of
behavioural categories to novel scenarios, you must
be able to recognise that there are different ways
Figure 0.22: Animals may show behaviours such
as running, grooming or eating.
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Covert and overt observations
Another important consideration for studies using
observation is where and how the researcher will watch
the participants. In some cases, psychologists might
physically watch participants from the same room or
location. In other cases, they may choose not to be
present. For example, researchers may video record
participants, observe from a distance or through
one-way mirrors (see Figure 0.23).
Applying knowledge of covert
and overt observations
To apply your knowledge of covert and overt
observations to novel scenarios, you must be able to
suggest suitable types of observation that researchers
can use to achieve the aim of their research. This could
involve selecting whether a covert or overt method is the
most suitable method, and how this could be achieved
by an observer in practice.
Sometimes, it may be more appropriate to use a covert
method, when it is especially important that the
participants do not know they are being watched. For
example, psychologists interested in social behaviours
might prefer a covert observation as they are specifically
looking at how people act when they are around
other people.
Figure 0.23: Psychologists can observe participants
covertly through a one-way mirror.
When it is obvious to participants that they are being
watched, we describe this as an overt observation. In
an overt observation, the observer is visible to the
participant, and might be holding a clipboard to record
their notes. By contrast, if the observer is hidden from
the participant and / or the participant is unaware they
are being watched, this is known as a covert observation.
There are ethical issues with covert observation, as
participants do not give their informed consent to be part
of the psychological research. You will learn more about
ethics and specifically informed consent in Topic 0.7.
KEY TERMS
Overt observation: role of observer is obvious
to the participants and the participants know
that they are being observed.
In other cases, psychologists might decide it is more
ethical or practical to observe overtly; as the effect of
their presence may not influence behaviour too much, or
it would be ethically harmful or too difficult to secretly
watch their participants in the environment they have
chosen. An example of this might be in the workplace,
where participants might naturally notice the presence
of a stranger, and the employer wants to be honest and
transparent that the employees were being watched to
maintain their trust.
Although you do not need to evaluate different types
of observation, it is useful to understand the concepts
of validity and reliability in relation to this method.
For example, we often use structured observations
using behavioural categories as one way to improve
reliability. That way, if an observation is repeated, or
conducted by a different observer, they are likely to
get the same results.
On the other hand, validity is about observing the
behaviour we intend to observe. If a researcher is
conducting an overt observation, they will need to
consider how this will affect the outcome of the study.
As mentioned earlier in the example of observing social
behaviours, psychologists must decide whether their
observation will still be valid if their participants know
they are being watched.
Covert observation: role of observer is not
known or obvious to the participants, as the
observers are hidden or disguised.
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ACTIVITY 0.8
CONTINUED
A psychologist is interested in understanding
littering behaviour in public parks. She wants to
see whether different types of people use bins/
trash cans provided; or whether they leave litter
on the ground. Working on your own, answer the
following questions.
•
1
Do you think the psychologist should use
an overt or covert observation?
2
In your own words, describe how the
psychologist could use each method.
3
What practical or ethical issues might
the psychologist have if they conduct a
covert observation?
4
If the observation is overt, how might
this effect the validity of the study?
Questions
State one feature of a structured observation.
Outline the difference between a covert observation
and overt observation.
Explain why researchers choose to use unstructured
observations.
4
5
6
COMMAND WORDS
State: express in clear terms.
Outline: set out main points.
Explain: set out purposes or reasons/make the
relationships between things clear/say why and/
or how and support with relevant evidence.
•
Research Methods
There are different types of observation
including:
• Structured and unstructured. Structured
observations use behavioural categories
which must be operationalised, and
researchers use checklists or tally charts
to record behaviours. In unstructured
observations, there is no fixed list of
behaviours to record.
• Covert and overt. In covert observations
the researcher is hidden or disguised; in
overt observations the participants know
they are being watched.
Observations are used in different ways by
researchers to achieve their aims. The choice
of observation can affect the reliability,
validity and ethics of the research.
0.3 Non-experimental
methods: questionnaires
and interviews
Questionnaires and interviews are sometimes referred to as
‘self-reports’. This is because their key feature is that they
require the participant to directly provide information on
personal thoughts, attitudes, and beliefs to the researcher.
Questionnaires and interviews are used throughout
different areas of psychology to collect data about
variables. Just like observation, questionnaires and
interviews are techniques that can be used within other
research methods. For example, a questionnaire might
be the technique that a researcher uses to understand a
participant’s experience of childhood in a case study.
KEY POINTS
KEY TERMS
•
Questionnaire: a method of collecting data by
asking written questions to participants.
•
Observation is a non-experimental research
method and data collection technique.
An observation is when the researcher
watches and records behaviour.
Interview: a method of collecting data by asking
verbal questions to participants.
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Questionnaires and interviews can also be used as a
research method on their own without the requirement
to measure and manipulate variables, and so we
consider them here as non-experimental. There are a
range of reasons why researchers will select different
research methods, and each has implications for validity,
reliability and ethics in research. You can read more
about issues of validity, reliability and ethical guidelines
and how they relate to questionnaires and interviews
later in this chapter.
Questionnaires
Questionnaires consist of a list of questions that are
generally placed in a set order.
Attitudes to Exercise Questionnaire
1. How interested are you in exercise?
(circle one)
a. Not interested at all
b. Slightly interested
c. Moderately interested
d. Very interested
3. Did you exercise today? (circle one)
No (skip to question 5)
Yes
4. If yes, please give details of the
type of exercise:
Figure 0.25: In some questionnaires, participants are
instructed to skip questions or to provide more detail.
The way in which the questionnaires are administered
depend on the aims of the research. Questionnaires can
be given to participants to complete using paper and
pen / pencil, or they can be administered online / via
computer, tablet or mobile phone.
There are practical and ethical considerations for
researchers using questionnaires:
•
•
The researcher must consider the most suitable way to
provide the questionnaires. Will their sample have easy
access to a computer, for example (see Figure 0.26)?
Can the questionnaire be completed anonymously
to help protect the privacy of the individual and /
or gain more honest responses?
These considerations are explored later in this chapter
in Topics 0.7 and 0.8.
e. Extremely interested
2. How important do you believe exercise
is for overall well-being? (circle one)
a. Not important at all
b. Slightly important
c. Moderately important
Figure 0.24: Questionnaires are used in psychology
to gather data from large numbers of participants.
For this reason, they are usually more structured than
interviews. However, sometimes researchers create
questionnaires in which participants are instructed to
skip questions that do not apply to them, or requested
to add more detail if they respond to a question in a
certain way.
Figure 0.26: Some groups of participants, such as
those in hospital, may have difficulty participating in
online research for practical reasons.
Interviews
Unlike questionnaires, interviews require researchers
to speak the questions aloud to the participant
(Figure 0.27). Interviews can use the same format as
questionnaires, but sometimes researchers choose to use
interviews for specific reasons. For example, interviews
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allow greater flexibility in the order the interviewer
asks the questions. This can work well if some of the
interview items are questions which produce responses
that lead more naturally to asking questions in a
different order or including alternative questions.
Research Methods
or to ask questions spontaneously, an interview may be
more appropriate. For example, if a researcher wanted
to understand people’s childhood experience, they might
use interviews to get in-depth information and explore
topics that arise in the discussion.
Questionnaires, by contrast, can be distributed quickly
to a large audience. Use the following Psychology in
real life feature to explore how you can apply your
understanding of questionnaires to a novel scenario.
PSYCHOLOGY IN REAL LIFE
Figure 0.27: Some interviews are done in person,
which allows the interviewer greater flexibility when
asking questions.
Similar to questionnaires, the way in which the interviews
are administered depend on the aims of the research. For
example, interviews might be more suitable for gaining
detail and in-depth responses to questions. Interviews
may be less suitable because they can be more timeconsuming to complete than questionnaires, and there
may be more ethical issues to consider, such as privacy.
Applying knowledge of
questionnaires and interviews
To apply your knowledge of this non-experimental
method, you will need to be able to recognise the
features of both questionnaires and interviews.
You should be able to consider the different choices
psychologists make about whether to use either method.
It is helpful to consider the following questions in
making the decision:
•
•
•
Can you collect data personally, or can it be
collected in the participant’s own time?
Is it important that the identity of the participant
is unknown, or will personal interaction with the
participant be likely to get more useful data?
Do you need in-depth information about a few
people, or a large sample?
Interviews usually are conducted on smaller samples
of participants for practical reasons; they generate lots
of data and are very time-consuming for researchers
to conduct. If there is a scenario in which a researcher
wants in-depth data, flexibility to change their questions
Imagine you are a captain, putting together a
team of people for a mission to explore new
regions of space. You need to select a crew that
has the right skills and personality traits to ensure
your mission is successful. Just like any job, this
‘workplace’ has its own particular challenges
and opportunities. This means that if you are in
charge of recruiting, you want to get the right
people for the role and the team!
This is where psychological questionnaires and
interviews can be used in real life. For example,
suppose the job requires the individual to be
confident, outgoing and happy to talk to lots of
different kinds of people. Recruiters sometimes
ask job candidates to undertake questionnaires
designed to measure these aspects of their
personality. Questionnaires can therefore be
used as a tool to make hiring the right person
more efficient.
Research evaluating how useful personality
testing is to successful recruitment has found a
strong relationship between suitable personality
traits and job performance (Alhendi, 2019). For
example, people rating themselves highly for
being ‘agreeable’ on a personality test was a
good predictor of that person working well in a
team. Psychologists design these questionnaires
for use on a huge scale. One main example
would be the five-factor model, which describes
human personality across five main areas.
Answer the following questions:
1
2
Why do you think recruiters for jobs use
questionnaires to help them hire people for
specific roles?
Can you think of any practical or ethical
problems with using questionnaires to help
hire candidates for jobs?
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Types of question
Both closed questions and open questions can be used
in either questionnaires or in interviews.
Closed questions have a fixed set of possible responses.
A fixed response is when the participant has little choice
of how to answer. This is because there are a small
number of possible responses they can make for this
type of question.
ACTIVITY 0.9
Create a fixed response question with a
rating scale to measure each one of the
following scenarios:
•
•
A person’s feelings towards a new park
being built in their neighbourhood.
How likely a person is to help an older
person in need.
Someone’s attitudes towards using
social media.
There are several types of fixed response that a
researcher can use when designing closed questions.
These can be:
•
•
yes or no answer questions, for example:
SELF-ASSESSMENT
Do you study psychology? Yes / No
After you have created the fixed response
questions individually, share them with another
person. Consider the questions the other
person created: were they the same or different
to your own? Write one thing you have learnt
about designing fixed response questions from
this exercise.
•
asking participants to tick / check a list of
responses that apply to them, for example:
How often do you receive homework? (tick all
that apply) every day / once a week / never
•
a rating scale. These can be numerical, for example,
choosing a number between 0 and 10, or asking for
a level of agreement with a statement. For example:
How much do you enjoy studying psychology on a
scale of 0–5? (0 = not at all, 5 = very much enjoy)
How much do you agree with the statement
‘Psychology is an interesting subject’? (strongly
agree / somewhat agree / somewhat disagree /
strongly disagree)
By contrast, open questions do not require a fixed
response. The participants can give a full response with
detail, using their own words. Open questions may start
with words such as ‘Describe…’ or ‘Why…’, which
encourage longer responses than closed questions.
For example:
•
•
Describe your preferred ways of studying.
Why did you choose to study psychology?
KEY TERMS
Figure 0.28: Questionnaires can be distributed
to large samples of participants to gain a lot of
information in a short time.
Closed questions: questions with a fixed set of
possible responses.
Open questions: questions that require detailed
answers in participants’ own words; no answer
choices are given to participants.
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Applying knowledge of open
and closed questions
To apply your knowledge of open and closed questions
to novel scenarios, you must be able to suggest suitable
types of question for questionnaires and interviews that
would help researchers achieve the aim of their research.
This could involve selecting whether open or closed
questions are most suitable, or a combination of both.
You should also be able to distinguish a range of fixed
response questions and understand how psychologists
can use these in novel situations. Use the questions in
this topic to check that you can apply your knowledge
of open and closed questions to novel scenarios.
ACTIVITY 0.10
The local town planners are going to build a
playground in your neighbourhood. They need
to gather information about how local people
feel about this building project. Using your
knowledge of questionnaires and interviews,
answer the following questions:
1
2
Would you want to conduct interviews or
give questionnaires to the local people
to find out about their feelings about the
playground project? Justify your decision.
Questions
7
If a question produces only numerical data,
what type of question must it be?
Give two types of fixed response question.
Write an open question that could be used in
a questionnaire about students’ subject choices.
8
9
COMMAND WORD
Give: produce an answer from a given source
or recall/memory.
KEY POINTS
•
•
•
•
Write one open and one closed question that
you could ask local people when gathering
this information.
REFLECTION
Consider the research method you have just read
about: use of questionnaires and interviews.
•
•
•
What connections did you make with your
own experiences and knowledge?
Did you find anything difficult to understand?
How did you resolve any challenges
you experienced?
Research Methods
•
Questionnaires and interviews can be used
as non-experimental research methods and
data collection techniques.
A questionnaire is a written list of questions,
which a participant responds to using paper/
pen or via computer.
An interview is when a participant responds
to verbal questions from a researcher.
There are different types of question that
can be used in both questionnaires and
interviews including:
• Closed questions. These require a fixed
response and there are a small number
of options the participant can choose
from. Fixed response items include yes/
no items, checklists and rating scales.
• Open questions. These do not require
a fixed response, and the participant
can give an extended answer in their
own words.
Questionnaires and interviews are used in
different ways by researchers to achieve
their aims. The choice of questionnaires and
interviews can affect the reliability, validity
and ethics of the research.
25
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0.4 Non-experimental
methods: case studies
(such as a family), or an event. By focusing on just one
example, the researcher can gain an insight into often
unique or rare phenomena. For example, psychologists
might wish to use the case study method to investigate:
Case studies can be considered a research method in
their own right without the requirement to measure and
manipulate variables, which means they are described
here as non-experimental.
•
•
•
•
•
developmental changes between childhood
and adulthood
long-term mental or physical illness and its effect
on the participant
the effects of brain injury on memory and other
cognitive processes
the outcomes of educational interventions on a
particular class of students
criminal cases where psychological factors have
played a role.
Collecting data in case studies
Psychologists may choose to use a range of techniques to
collect data about their participant, to check whether they
produce similar findings. This comparison can then be
used to help the researcher judge whether their findings
are valid. You will learn more about validity in Topic 0.7.
Figure 0.29: ‘Little Albert’ is a classic case study in
psychology of a small child, exploring how fear can
be learnt.
TIP
Research methods
Case studies in psychology differ from case
studies you might learn about in other subjects.
In other subjects such as law and business,
they are often used as real-world examples of
legal principles or ‘what works’ in organisational
practice. However, in psychology, we are
concerned with individual behaviour, experiences
and psychological processes.
Case studies are used less frequently than other methods
you will learn about in the study of psychology. This
is because their key feature is that they are a detailed
investigation of a single person, very small group
Tests and tasks
Depending on the aims of the case study, psychologists
might wish to include tests or tasks for the participant
to undertake. This can help the researcher explore
what is unusual about the person they are studying
(Figure 0.30).
Tasks or tests can be used to establish changes in a
participant over time, or to allow the abilities of a
participant in the case study to be compared to the
results of people from a wider population.
For example, a person in a case study with an unusually
good memory might be given a test of memory to identify
what their strengths are, such as their ability to remember
the events of their daily lives. Their test scores can then be
compared to the scores of people with average memories.
KEY TERM
Case study: in-depth investigation of a single
individual, group or event.
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Likewise, a task involves the case study participant
performing a particular action or set of actions that
the researcher can then observe or evaluate. In one
scenario, psychologists might be studying a person who
has regained some vision after experiencing previous
sight loss. The psychologists might want to observe how
that person now uses their senses to navigate and move
around in their environment, studying whether there is
change in that individual’s behaviour over time.
Research Methods
Observations
Observations are also a widely used technique in case
studies. Suppose a psychologist is interested in studying
a particular child’s play behaviour. They may decide
to watch them play with friends at the playground
and note how the participant interacts with other
children and their environment. By paying attention
to their choice of play activities, and how they resolve
problems with friends, the researcher can gather insight
into their development. This data can be compared to
data collected through other techniques to check for
similarities and differences.
Figure 0.30: Case studies allow psychologists to
explore what is unusual about the person they
are studying.
ACTIVITY 0.11
There are many fascinating case studies that
focus on people with amnesia. Because this kind
of memory impairment is relatively rare, being
able to study people with amnesia using the case
study method can help psychologists develop a
better understanding of memory and forgetting
that it might be unethical or impractical to find
out/discover in any other way.
For example, the named study HM amnesia
(Milner and Corkin) (Topic 1.5: The brain in
memory and forgetting) uses a number of
techniques to collect data about the patient HM.
Discuss the following questions with a partner:
1
What data collection techniques were used
in the case study?
2
Why do you think the researchers used
multiple data collection techniques?
3
What ethical considerations should
researchers be aware of when undertaking
case studies with participants who have
experienced brain damage?
Figure 0.31: Psychologists might want to observe
a child playing with others to record different
behaviours and interactions.
Questionnaires and interviews
Researchers might use a questionnaire or interview
to help them understand a participant’s experiences.
Using the example of observing children playing in
the previous section, a psychologist might seek to
interview the child’s family members, teachers or friends.
Questionnaire and interview findings can be compared
to the results of tests, tasks and observations.
Using a range of techniques also fulfils another
important role in case studies: collecting important
contextual information about the participant’s life
history, upbringing, culture and environment. This
information is usually personal and very detailed. For
this reason, it can be impractical to carry out case
studies on larger numbers of people. In some case
studies the researcher may get to know the participant
over many years. This places additional responsibility on
researchers to ensure they follow all ethical guidelines,
especially such as privacy and the right to withdraw.
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Triangulation
Triangulation in case studies is one way that researchers
can check whether the date they have collected is
reliable and valid. Looking at a case from different
angles can help us to understand the participant better.
In triangulation, the researcher uses multiple sources
or research methods to collect data like interviews,
observations and tests.
For example, imagine a researcher wanted to study
motivation in a world-class athlete. They could
interview the athlete, as well as their teammates or
coaches, and also observe the athlete in training.
This would give them a more complete picture of
what motivates the athlete, and they could check the
information provided by the athlete against what
was observed or learnt from their colleagues. By
combining and comparing the different sources of
data, the researcher can be more confident about
their conclusions in the case study.
Applying knowledge
of case studies
To apply your knowledge of this non-experimental
method, you will need to be able to recognise the key
features of case studies. You should understand the
factors that might lead to a psychologist choosing to use
a case study as their method of investigation.
As part of this you need to be able to suggest suitable
data collection techniques a researcher can use,
including tests / tasks, observations, questionnaires and
interviews. You should also be able to understand how
researchers reach conclusions in case studies, including
in novel situations.
ACTIVITY 0.12
Time to investigate! Read the following information
and plan your own psychological case study.
can help you to compare different sources of data
about Judy’s lateness.
A student called Judy is always late for her maths
class. Her teacher is keen to find out why the other
students arrive on time, but Judy is often around
ten minutes late at least once a week.
In a small group, chose one of the following factors
to investigate:
•
•
•
Judy’s personality (her personal attributes
and attitude)
Judy’s routine in getting to class (how
she travels and what else she does
before class)
Judy’s home life (her family and pets).
In your group, write a short plan of how to collect
data to investigate the factor you have chosen.
You should consider the data collection technique
you will use, and some brief details: for example,
tasks Judy should complete or questions you might
ask. Present your plan to the class and as a whole,
consider how all the plans from your class members
Figure 0.32: How could a case study be used to
investigate the reasons for lateness?
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Research Methods
Questions
Sample
10 Define what is meant by a case study.
11 Give two examples of when it might be suitable
for a researcher to use the case study method.
12 Explain how a researcher can triangulate their
findings in a case study.
Since the population is too large to collect data from
in its entirety, instead psychologists collect data from a
sample of the population. This means studying a much
smaller selection of the population that they want
to be able to make conclusions about. The sample
will be selected from the population that share the
relevant characteristics.
COMMAND WORD
Define: give a precise meaning.
KEY TERMS
KEY POINTS
Population: group of people with one or more
characteristics in common, from which a sample
is selected.
•
•
•
•
A case study is a non-experimental
research method that uses various data
collection techniques, including tests/tasks,
observations, questionnaires and interviews.
Case study researchers use these different
sources of data to make conclusions.
Case studies are typically used to investigate
psychological phenomena that are unusual
or unique in some way.
This method is often selected to help
understand areas of psychology that it may
be unethical or impractical to study through
experiment or on a larger scale.
Sample: a group of people selected to represent
the population in research.
0.5 Sampling
This topic considers the aims of sampling in psychology
and techniques that researchers typically use.
Population
When conducting research, psychologists are often
seeking to test whether their ideas are true of many,
if not all people. The term population refers to all the
members of the group that the psychologist wants to
make a conclusion about. For a psychologist looking
to investigate the experience of mature students at
university, the population of their research would be
all members of that group (mature students).
Figure 0.33: Psychologists wanting to study the
experiences of mature students will need to take
a sample from that population.
Characteristics of the sample that might be of interest
to psychologists will often include the age, sex and
occupation of their potential participants. In the
earlier example of the mature student population,
psychologists might seek to gain a sample of people
who are over the age of 25, at one or more universities.
Sample size is also very important. The number of
participants to be included in the sample will depend
on the type of research method and data collection
technique that the researchers are using. As we saw
earlier, questionnaires can be distributed relatively easily
to thousands of participants, particularly if they contain
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closed questions that collect data that is straightforward
to analyse and compare. Alternatively, case studies have
a sample size of one or very few participants because
of how in-depth the data collection is, and the unique
nature of the phenomena being studied.
TIP
Research methods
The terms ‘population’, ‘sample’ and ‘sampling
technique’ can often be confused and it is
important to be clear about what each means in
psychology. The population includes all possible
candidates to become participants; remember
this group will have shared characteristics
relevant to the researcher’s aim. The sample
is the selection from the population, and the
sampling technique refers to HOW the sample
was selected (see Figure 0.36).
Figure 0.34: Questionnaire samples often have large
sample sizes, as they are a way to gain information
quickly once they have been designed and distributed.
MAKING CONNECTIONS
You might be familiar with the term ‘sample’
from other subjects. In science, it also refers to
taking measurements from a smaller selection of
an environment you are studying. For example,
a biologist might extract a cup of water from a
lake and conduct tests to establish the levels of
certain microorganisms and therefore whether
it is safe to drink. In this case, the ‘lake’ is the
population and the cup of water is the sample. If
the water in the cup is safe to drink, the scientist
will assume that the water in the lake is probably
safe to drink also!
Sampling technique
Once a researcher has decided how many participants to
include in their sample, they will then need to consider
the different ways to access these potential participants.
The sampling technique is the method used to obtain the
sample from the population. There are lots of different
ways researchers do this in practice, and we will consider
these later in the chapter.
Figure 0.35: The sample is selected from the
population using the sampling technique.
Applying knowledge of populations,
samples and sampling techniques
To apply your knowledge of populations, samples and
sampling techniques to novel scenarios, you will need
to be able to recognise the key features of each and
consider the factors that might lead researchers to make
decisions about their choice of sample. You can apply
your knowledge in the following questions.
KEY TERM
Sampling technique: method used to select
research participants from the population.
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Research Methods
Questions
Opportunity sample
13 Outline a population for each of the following
scenarios. State the sample size the researcher could
use for each, and write down one other feature of
the sample you think could be relevant:
Researchers can choose their sample simply by
using the people who are available at the time of the
research. This method of sampling will produce an
opportunity sample, because the sample is chosen by
‘opportunity’. Researchers will approach people to take
part who fit their criteria for age, sex, location or other
characteristics relevant to their research.
•a questionnaire on stress levels in
university students
•an experiment on how sleep affects
children’s mood
•an interview about males’ and females’
use of social media.
For example:
Research
scenario
Population
An
Adults
observation who are
of
employed
obedience
in the
workplace
Feature(s)
Sample size of the
sample
10–15
people
Males and
females
Aged
between
18 and 65
14 For one of the scenarios in question 13, explain
how you could obtain this sample. Justify
your answer.
REFLECTION
In the real world, researchers discuss their design
choices, and often will take different approaches
to collecting their participant samples. This task
will help you reflect on your own work as you
collaborate with others.
Swap your responses to questions 13 and 14
with another student. Identify similarities and
differences between your responses. Discuss
in your pair and try to give a reason why a
researcher might choose one approach or select
one particular feature over another.
What might you do differently in an exercise like
this next time?
Figure 0.36: University students can be approached
on campus as part of an opportunity sample.
Many studies are conducted on university students as
they are readily available for researchers to use. If you
conduct research as part of your study of psychology,
you would be likely to use an opportunity sample.
Opportunity sampling is a commonly used method
for students of psychology as well as professional
researchers. It is a straightforward method for
researchers to use when they need a convenient sample.
Applying knowledge of
opportunity sampling
To apply your knowledge of opportunity sampling to
novel scenarios, you will need to be able to recognise the
features of this sampling technique and when and why it
is used in practice.
KEY TERM
Opportunity sample: participants are selected
because they are available at the time
of research.
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In the real world, a researcher who is aiming to study
the effects of a new therapy might approach their
patients from their own clinic to take part in the study.
It is straightforward as the researcher already knows the
participants will be diagnosed with the mental health
condition that the therapy is designed to treat.
the population they are interested in sampling. This
information can be, for example, shared through printed
posters, shared on social media, emailed to groups
of people who fit the requirements or displayed in an
advertisement in a newspaper.
Another example can occur when researchers are
conducting a study in a public place. If the researcher
is studying social behaviours, they can visit a market
and ask shoppers to take part in their questionnaire or
experiment. As many people are available in this space, it
makes recruiting an opportunity sample a logical choice.
ACTIVITY 0.13
In this activity, you will learn about how
opportunity sampling works and how it can be
used to gather data from a group of people in a
novel scenario. You will need a bag of sweets of
different flavours and a pen and paper.
Gather a group of at least 10–15 participants, for
example, your classmates, for your opportunity
sample. Then, select two or three people who
are closest to you (an opportunity sample) and
ask them to sample the sweet flavours. Ask
them the following questions and write down
their responses:
1
Which is your favourite flavour of sweet?
2
How often do you eat sweets?
With the rest of the group, discuss these results
and how you collected them. How would the rest
of the group have responded? What might this
mean for the validity of your results?
Volunteer sample
Another common sampling technique is collecting a
volunteer sample. It is another practical method, and
it is also sometimes called ‘self-selected’ sampling.
This is because it requires people to volunteer or select
themselves to participate. This occurs in response to
researchers advertising or making people aware that
they require participants for their study. The potential
participants who see the advertisement then contact the
researchers to volunteer themselves for the sample.
When advertising for a volunteer sample, researchers
will usually include details of the characteristics of
Figure 0.37: Psychology students often advertise for
research participants using volunteer sampling.
Applying knowledge of
volunteer sampling
To apply your knowledge of volunteer sampling in
novel scenarios, you will need to be able to understand
the reasons it is used by researchers, and to recognise
scenarios in which it has been used.
ACTIVITY 0.14
Mr Okie wants to find out which classroom layout
his students prefer: rows, group tables or a
U-shape layout facing the front of the room.
Working on your own, describe two different
ways Mr Okie can collect information on students’
preferences, using volunteer sampling. Try to be
specific so this could be conducted in real life.
KEY TERM
Volunteer sample: participants choose to take
part in research by responding to an invitation
to participate.
If a researcher is aiming to study the effects of an
exercise on mental health, they could use volunteer
sampling as a technique. By placing posters advertising
their study in a gym or sports centre, they are likely to
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0
get the attention of people from their target population.
These people are engaging in exercise and may be
interested in volunteering.
Another real-world example might be if researchers
are looking to study people’s reasons for recycling. A
good place to advertise for a volunteer sample might be
on the social media pages of environmental groups or
displaying posters about the study at a recycling centre
asking for people. The potential participants can then
read about what they need to do in the study and get in
contact with the researchers if they want to take part.
KEY POINTS
•
•
•
Sampling is the way in which researchers
select and recruit participants in psychology.
Researchers will identify a population for
their study, then decide on a suitable sample
of people to take part.
Sampling techniques such as opportunity
and volunteer sampling are used to select
participants with the appropriate features to
participate.
KEY TERM
Validity: extent to which the researcher is
investigating what they aimed to investigate.
Research Methods
0.6 Validity and reliability
Validity
It is important that any research that is carried out
has validity. Validity refers to the extent to which the
researcher is investigating what they aimed to investigate.
Validity refers to the extent to which you can be
confident that any changes in the dependent variable
are due to changes to the independent variable. To be
sure of this, any other variables that could affect the
dependent variable (extraneous variables) need to be
controlled for. So if you are confident that any changes
in the dependent variable are only the result of changes
to the independent variable (because other variables
have been controlled for) this means that the research
is valid. In research where extraneous variables have
not been identified and controlled for the research is
not valid because there is no way to know whether
changes in the dependent variable are due to changes to
the independent variable or to any other uncontrolled
variable. If research is not valid it is not useful because
it does not tell us anything very helpful.
For example, if you are trying to investigate the effect
of hunger on memory recall, it would be important to
identify and control for extraneous variables such as the
words to recall; the time of day; or any distractions in
the room. If research is carried out with these extraneous
variables controlled for, the research will be valid so the
results can be trusted. If results showed that fewer words
Figure 0.38: Controlling for extraneous variables in a task such as memory recall will increase the validity.
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were correctly recalled by participants who had not
eaten for 12 hours than by participants who had just had
a meal, we could confidently say that the difference in
memory recall is due to hunger. We could conclude that
hunger reduces memory recall. However, if the extraneous
variables mentioned before had not been identified and
controlled for, the results would not be valid as there
would be no way to know whether a change in the number
of words recalled was due to change in hunger or not. The
difference in words recalled could be due to using different
words for the recall list (for example, more complex words)
or due to a room that had noisy building works going on
next door or due to tiredness if one condition was carried
out much later in the day. In this case, the results are not
valid and they do not tell us anything useful as we are not
able to say what caused the change in memory recall.
ACTIVITY 0.15
Another student wants to carry out an
investigation into whether fruit and vegetable
intake affects sleep. They are planning to
measure sleep quality using a tracker for one
week. Then they will ask participants to eat more
fruit and vegetables for one week and then track
the quality of their sleep for another week.
The student asks for your advice on how to carry
out this research. Write down your ideas:
•
•
•
Tell the student why it is important to make
sure their research is valid.
Suggest at least two extraneous variables
that the student needs to consider.
Suggest a way that each of these extraneous
variables could be controlled for.
Objectivity
Objectivity refers to research that is not impacted by the
personal opinions and feelings of the researcher, meaning
that it is unbiased. Objectivity increases the validity
of the research because it means that the researcher’s
opinions are not affecting the way the research is carried
out, how the data is interpreted or what conclusions are
drawn. This means that the results cannot be interpreted
in different ways by different people, and researchers can
be much more confident in what the results show.
For example, if a researcher is investigating the effect
of dancing on happiness level, objective measures
of happiness are observing the number of times
participants smile and laugh, or asking participants
to rate their happiness on a scale of 1–10, where 1 is
extremely unhappy and 10 is extremely happy. These
measures do not require interpretation from the
researcher, so they are objective.
To make sure research is objective a researcher will
ensure that, as much as possible, nothing in their
research is open to interpretation or can be influenced
by their own opinion. There are many ways a researcher
can increase objectivity:
•
•
•
Operationalising variables: when we operationalise
variables, we describe them in a way that is specific
and measurable. This increases the objectivity of
the research, and therefore the validity, because
it means there is less room for opinions or
interpretations of findings. (For more information
on operationalising variables, see Topic 0.1.)
Behavioural categories: these should be specific and
objective when carrying out observations. The more
specific the behavioural categories, the less open
they are to interpretation. This makes the research
more objective and therefore more valid. (For more
information on behavioural categories, see Topic 0.2.)
Standardised procedures and instructions: in
research it is vital to make sure that all procedures
and instructions are standardised. This means that
they are the same for all participants. This increases
the objectivity because it means that the researcher
is not explaining things differently to participants
in different conditions, which could lead to
different results.
For example, research into the effect of stress on
memory might require some participants to carry
out a memory task under time pressure, while
others carry out the memory task with no time
pressure. The way instructions are given should be
identical for all participants so that this does not
influence their performance. For example, if those
in the ‘no stress’ condition were given very strict
instructions by a researcher in a very stern tone,
who emphasised the importance of the research
and that the participants should perform well, this
could lead to them feeling stressed. By contrast,
if those in the ‘stress’ condition were given calm
and straightforward instruction by a very friendly
researcher who told them not to worry, they may feel
less stressed than the ‘no stress’ participants. This
would of course influence the results and decrease
the validity of the research as we would not be
confident what effect stress actually had on memory.
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•
Physical or numerical measures: an ideal way to
make sure research is objective is in the choice of
measures that are used. Physical measures such
as heart rate, temperature, blood pressure, and
brain scans are objective measures because they
are measured using scientific equipment and are
not reliant on the interpretation or opinion of the
researcher. Numerical measures such as number of
errors in a task, number of correct answers and time
taken are also objective measures because they are
specific and quantifiable so they are also not reliant
on the interpretation or opinion of the researcher.
ways by different people, which reduces how confident
we can be in what the results show. As much as possible,
researchers try to reduce the effects of subjectivity.
There are different ways in which subjectivity can cause
a problem in research. Here are some examples of
subjectivity in research:
•
KEY TERM
Objectivity: not impacted by personal opinions
and feelings; unbiased.
Figure 0.39: Objectivity is increased by using numerical
measures such as time taken to complete a task.
•
Subjectivity
By contrast, subjectivity means that research is affected
by the personal opinions and feelings of the researcher,
meaning that it is biased. Subjectivity reduces the validity
of the research because the researcher’s own opinions
are affecting the way the research is carried out, how the
data is interpreted or what conclusions are drawn. This
means that the results could be interpreted in different
KEY TERM
Subjectivity: impacted by personal opinions and
feelings; biased.
Research Methods
•
Interviews:
• If participants are emotional during an
interview, this can affect the emotional
response of the interviewer, which can
influence the way responses are interpreted,
therefore reducing the validity of the research.
• Interviewers can also use leading questions,
which means asking a question in a way that
suggests the answer they are expecting. For
example, a leading question might be worded
as ‘Can you explain how upsetting that was
for you?’ rather than ‘How did you feel about
that?’. The leading question implies that the
situation must have been upsetting, which
means that participants’ response will likely be
influenced by the expectation of the interviewer.
• A further way interviews can lead to subjective
research is through interpretations and analysis
of the responses given. As interviews tend to
provide qualitative data, long answers with
lots of detail, this relies on the researcher
interpreting the data, which is almost
impossible to do without being influenced by
their own expectations, emotions or biases.
This reduces the validity of the research
because it is not an accurate and unbiased
account of the findings.
Using data that supports a theory: researchers
may ‘choose’ to focus on any data that supports
their theory, and ignore data that might challenge
it. Imagine carrying out research to investigate a
question that you have been planning for a long time.
Some of the data you collect backs up your theory
and shows what you expect to find, but some of the
data does not fit with your expectations. It would
be very tempting to focus on the data that agrees
with your theory, or to interpret data in a way that
backs up your expectations. This, however, reduces
the validity of the research as it does not truly and
accurately show what the research actually found.
Observation without behavioural categories: in
contrast to the use of behavioural categories to
increase objectivity, observations that are carried
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out without behavioural categories are subjective.
If a researcher is observing someone without a set
of previously determined behavioural categories
it means that they will be more likely to use their
own judgement and interpretation of what they are
observing. This means that they may be more likely
to record certain behaviours that support their
research theory and ignore other behaviours. It can
also mean that a behaviour is interpreted to fit with
expectations before it is recorded.
For example, imagine you are carrying out an
observation to see how mothers interact with their
babies. A mother is not interacting with her baby,
the baby cries and the mother picks it up. You
could interpret this as either:
•
•
the mother ignoring the baby so the baby gets
upset or
the mother comforting the baby when it cried.
The way the same behaviour is interpreted is likely
to be influenced by the expectations of the observer
so this makes the researcher more biased and
subjective and less valid.
ACTIVITY 0.16
Objectivity is a vital part of validity. For each of
the variables, suggest an objective way and a
subjective way of measuring the variable.
1
Anxiety
4
Excitement
2
Fitness
5
Performance
3
Maths ability
Discuss your answers in pairs and, for each
variable, discuss which is the best way of
measuring it. Why is it the best way?
Reliability
It is important that research has reliability. This
means that the method we use to collect research data
is consistent and carried out in the same way for all
participants. Reliability also means that if you carry
out the same research on the same participants under
the same conditions you should get the same results
each time. If you do not get the same results this would
suggest that the method is unreliable as something must
be different in the method if the results change.
For example, imagine you are investigating the effect of
the presence of other people on performance anxiety.
You want to make sure that everything about your
procedure is the same for every participant, apart from
the presence of other people, because this is what you
are investigating (independent variable).
Figure 0.40: Observing a mother comforting
her baby could be interpreted in different ways,
increasing the subjectivity.
Participants could be asked to perform a speech about
a given topic and their heart rate could be measured
before and after the performance as a measure of anxiety
(dependent variable). In the ‘alone’ condition participants
are in a room carrying out a speech on their own, and in
the ‘presence of others’ condition, participants are in the
room carrying out the speech with eight people present.
A reliable method would ensure that:
•
Applying knowledge of validity
to novel scenarios
All research that is carried out must be valid if it is
going to be useful. Now you have an understanding of
validity and how important it is, you can apply it to any
examples of research.
Participants in each condition are given the exact
same instructions, which should be written down so
they can be read out, making sure they are kept the
same each time.
KEY TERM
Reliability: consistency of procedure or measures
used to collect data in research.
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•
•
The same researcher (ideally) works with all
participants, and they interact with all the
participants in the same way, such as calm and
friendly rather than overly stern. If a different
researcher must be used, they should be trained
on how to interact with the participants so the
interactions are as similar as possible.
Participants are given the same amount of time and
resources to prepare their speech so that this does
not affect their performance anxiety.
Figure 0.41: The effect of the presence of others
on performance anxiety will differ depending on
how many people are present and how they
are behaving.
•
In the ‘others present’ condition, ideally the same
eight people are used for each participant, and these
people are told how to behave so this is consistent
for each performance. As you can imagine, if you
are performing a speech for eight people who are
sitting quietly and nodding along encouragingly,
this will be less stressful than if you are performing
a speech for eight people who are scowling, or
fidgeting or whispering amongst themselves.
Research Methods
Another vital aspect of research that must be reliable is
the gathering of data. This means that whichever way
the data is collected, whether through observations,
self-report or other methods, it must be consistent.
Inter-rater reliability
Inter-rater reliability is a really important aspect of
reliability as it refers to the consistency of judgements
made by multiple researchers, or ‘raters’, who are
reviewing the same responses. This means it measures
the extent to which two researchers agree on the
interpretation of participants’ responses.
We know that subjectivity can create bias in research
when researchers are influenced by their own
expectations or emotions (see previous section). A
good way of reducing the impact of this is to use two
researchers to rate the same response and see if their
interpretations are in agreement with each other.
If two (or more) researchers both interpret a
participant’s response to a situation or question in
the same way it means that there is high inter-rater
reliability. This means there is a high level of consistency
or agreement between their ratings, which means the
results are more reliable.
If the research was repeated, we would expect to see
the same results.
KEY TERM
Inter-rater reliability: consistency and agreement
between raters judging the same responses.
If all these aspects of the research are consistent for all
participants, and the only difference is whether there are
people present or not, it means the results are reliable,
making the research much more useful.
5 5
5
High inter-rater reliability
3
5 4
Low inter - rater reliability
Figure 0.42: Inter-rater reliability refers to the consistency between raters judging the same responses.
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If two or more researchers do not agree, or are not
consistent with their interpretation of the responses, there
is low inter-rater reliability. This means that the results are
not reliable. If the same research was repeated with the
same participants in the same conditions, we might expect
the results to be different as there has not been agreement.
A response from a participant can take different forms.
For example:
•
•
•
the way a participant responds to a stimulus
how a participant performs a task
what a participant says in an interview.
Commonly, in the context of inter-rater reliability,
the responses analysed are from interviews. Analysing
responses from interviews can be challenging for
researchers, especially when participants’ answers are
long and complex, with lots of qualitative data and
details. It can also be particularly difficult to analyse
responses for emotional or sensitive subjects.
If one researcher is interpreting the responses of an
interview, we know there is a risk that their expectations
and emotions may influence their interpretation and lead
to subjective research. Using two or more researchers
to interpret the same responses independently of each
other and then comparing their results is the best way
to check for reliability and reduce the impact of bias.
For example, imagine a participant is answering
a question about their views on climate change.
Their response is complex and includes:
•
•
•
•
how big a problem they think climate change is
what they think should be done about it by big
companies and by individuals
what they are doing personally to try to reduce
their impact
the statement: ‘but I sometimes also think it’s
not that big a deal’.
One researcher may interpret this response as the
participant being:
•
•
•
very concerned about climate change
very informed
proactively involved in reducing climate change.
However, another researcher might put too much
focus on the last statement and interpret the response
as the participant not being very concerned about
climate change.
This is a very simplified example and most researchers
would consider all aspects of the response provided
and try to give a fair summary, but it highlights the
difficulties researchers can face. If only one researcher
was rating the participant’s response, this could give a
very different interpretation of the participant’s views.
This could particularly be the case if a researcher has
their own theory or expectations about the results.
However, if two researchers each independently rate
the response and then compare their results to see if
they agree with each other, this reduces the risk of
subjectivity and increases reliability.
Inter-observer reliability
Inter-observer reliability relates specifically to the
agreement or consistency between two researchers who
are carrying out an observation. This means interobserver reliability is the extent to which two researchers
who are observing the exact same behaviour will
interpret that behaviour in the same way.
High inter-observer reliability means there is strong
agreement between two researchers carrying out an
observation. This means that the behaviour that has
been observed has been interpreted as meaning the same
thing by each researcher, so the results are consistent.
Low inter-observer reliability means there is little
agreement between two researchers carrying out an
observation. This means that the behaviour that has
been observed has been interpreted as meaning different
things by each researcher, so the results are inconsistent.
As with inter-rater reliability, research with high interobserver reliability means that if the same participants
were observed under the same conditions, we would
expect to get the same results. With low inter-observer
reliability, we would not expect to get the same results
if we observed the same participants under the same
conditions because the observations are not consistent.
Some observations are far more complex than others,
which means that it can be difficult to get high interobserver reliability. For example, imagine you are
investigating children’s play behaviour. It would be much
more difficult to observe a large group of children at a
park than to observe two children in one room. High
inter-observer reliability is harder to achieve with a
complex observation.
KEY TERM
Inter-observer reliability: consistency and
agreement between observers observing the
same behaviours.
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Research Methods
CONTINUED
Your presentation should include explanations
and examples of the following key terms:
•
•
•
•
•
•
validity
subjectivity
objectivity
reliability
inter-rater reliability
inter-observer reliability.
Follow these steps:
Figure 0.43: Inter-observer reliability can be difficult
in complex observations such as observing people in
a coffee shop.
One way to increase inter-observer reliability is through
the use of clear and specific behavioural categories.
This means that observers look for specific behaviours,
instead of relying on their own judgement of what
to record or how to interpret what they see. Using
behavioural categories makes it much more likely that
two or more observers will record the same observations
because they will be looking for the same behaviours.
For example, imagine two researchers are observing a
participant for signs of stress. They are told to record
any behaviours that might indicate that the participant
is stressed. The two observers could have very different
observations. One observer might interpret the
participant scratching their face as a sign of stress, but
another observer might not think it relevant and so may
not record it. However, if both observers are given a
list of behavioural categories to look for, and record, it
removes the influence of each observer’s own judgements
and increases the inter-observer reliability. For example,
when observing for signs of stress, behavioural categories
could include tapping fingers, chewing lip, pacing, and
so on. If an observer sees any of these objective and
observable behaviours, they can record them as a tally
without needing to be influenced by their own subjective
opinion, therefore increasing inter-observer reliability.
ACTIVITY 0.17
You are going to plan and deliver a presentation
to teach someone else about validity and
reliability. This person should be a friend or
family member who does not study psychology.
•
•
•
•
Start by planning what you want to say.
Remember your audience.
Use your ideas to create notes, flashcards or
a digital presentation using a computer. Try
not to write a script to read aloud. Instead,
use brief notes that you can quickly refer to.
Rehearse your presentation.
Deliver your presentation.
REFLECTION
Consider how you felt during the planning and
delivery of the presentation. Did you feel your
planning was effective? Did you feel confident in
the delivery of the presentation? If you found this
activity useful you could use this when studying
or revising other psychology topics.
At the end of your presentation, ask the friend or
family member what they have learnt and if they
have any questions. Answer any questions that
you can, using your own knowledge. If there is
anything you are not sure about, you could carry
out some research to find the answer.
Applying reliability to novel
scenarios
Now you have an understanding of reliability, and how
important it is, you can apply it to a range of different
research scenarios. Try Activity 0.18 to apply your
knowledge of reliability.
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ACTIVITY 0.18
Read the text. It is a response given by a participant
during an interview from research investigating if
television is good or bad for children.
‘I think children should be allowed to watch as
much television as they want to. I watched loads of
television when I was a child and it did not do me any
harm. I used to watch hours of television when I got
home from school.
‘Sometimes when my mum would tell me to turn the
television off I would get angry and upset, so maybe
it was not such a good thing after all. I think some
television can be really beneficial for children - lots
of children’s programmes teach things like taking
turns and playing well and healthy eating so children
get good things from it. But then some children
learn bad language or learn bad behaviours from
watching television too.
‘I think it is a good idea for parents to watch
television with their children so they can spend
time enjoying something together. I do not think it
is such a good idea to let children watch too much
television by themselves.
‘Watching television can be a good activity for children
because it means they can rest and have some quiet
time after a busy day at school. But the problem with
that is that children may be missing out on other
activities like being outside or reading. Sometimes
I think if I have children I will not let them watch very
much television but on the other hand most children
watch plenty of television so I would not want my
children to be the only ones who do not watch it.
Figure 0.44: Is watching television good for
children or bad for children?
Imagine you are a researcher who believes that
watching television is bad for children. Select
phrases in the text that you could use to support
your theory. Write these out under the heading of
‘television is bad for children’.
Now imagine you are a researcher who believes
that television is good for children. Select phrases
in the text that you could use to support your
theory. Write these under the heading of ‘television
is good for children’.
Compare the text you have written under each
heading. What does this tell us about subjectivity
and the importance of inter-rater reliability?
‘It’s a tricky topic and I have mixed views on it really.’
Questions
15 Define what is meant by the following terms:
a
validity
b
reliability
17 a
Give one difference between inter-rater
reliability and inter-observer reliability.
b
Give one similarity between inter-rater
reliability and inter-observer reliability.
16 Explain the difference between subjectivity and
objectivity. Include at least one example of a
subjective measure and one example of an
objective measure in your answer.
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0
KEY POINTS
•
•
•
•
•
•
Validity is the extent to which the researcher
is investigating what they aimed to
investigate. It can also be defined as the
extent to which the independent variable
is responsible for any changes to the
dependent variable.
Subjectivity refers to research that is
impacted by personal opinions and feelings,
making it biased. Subjective measures
include interviews, or observations without
behavioural categories. Subjectivity relates
to any research that relies on interpretation
by the researcher.
Objectivity refers to research that is not
impacted by personal opinions and feelings,
making it unbiased. Objective measures
include numerical or physical measures, and
observations using behavioural categories.
Objectivity refers to any research that does
not rely on interpretation by the researcher.
Reliability refers to the consistency of
procedure or measures used to collect data
in research. A reliable method is one that if
it is repeated, with the same participants,
under the same conditions, this would get
the same results. Reliability can be increased
by using standardised procedures and
instructions, making the experience the
same for all participants.
Inter-rater reliability refers to the extent to
which there is consistency or agreement
between researchers judging the same
responses, such as in an interview. High
inter-rater reliability means that two or more
researchers have interpreted the response
as meaning the same thing.
Inter-observer reliability refers to the extent
to which there is consistency or agreement
between researchers judging the same
behaviours, such as in an observation. High
inter-observer reliability means that two
or more observers have interpreted the
behaviour as meaning the same thing.
Research Methods
0.7 Ethical guidelines
This topic considers a number of important ethical
guidelines psychologists must follow when conducting
their research, to ensure the wellbeing and dignity of
their participants.
Ethical guidelines are an essential part of conducting
research in psychology. These are a set of rules that
help ensure psychologists minimise harm and maximise
benefit to their participants through any and all research
they conduct. Ultimately, the goal of psychology is to
help understand human thinking and behaviour in ways
that enrich our knowledge but also can be applied to
improve people’s lives.
KEY TERM
Ethical guidelines: general rules that researchers
need to follow to protect the rights and wellbeing
of the participants.
Figure 0.45: Ethics in psychology is about weighing
up potential benefits and costs to participants and
the wider public.
Following a code of ethics or ethical guidelines is one
way for researchers to make sure they have considered
any risks to themselves, their participants and the
reputation of psychology. Often, studies conducted by
researchers working at universities or clinical institutions
will have to explain how they are following ethical
guidelines. The ethics of a study, including any risks that
researchers identify with the research will be considered
by a panel or committee of people who will then give
approval for the study to be conducted.
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The key ethical guidelines in this topic are taken from
the British Psychological Society’s Code of Ethics and
Conduct (BPS, 2021). However, there are other similar
codes of ethics in use throughout the world.
vulnerable or has learning difficulties or reduced
awareness of their surroundings.
Consent
Consent is a person’s agreement to take part in psychological
research. Ideally, researchers would gain consent from all
participants, and this would be (1) informed and (2) valid.
By informed we mean that the participants have enough
awareness of the aims of the research and the tasks they
will perform in the study or topics that they will be asked
about for them to make a decision to participate.
In some cases, researchers wish to hide the real aim
of the study from participants. They may even seek
to deceive participants about what is happening in
the study, to ensure that they see realistic behaviour.
Researchers must make decisions about how much
information they can and should reveal to these
participants, to ensure they are following other ethical
guidelines, such as minimising harm.
In other cases, participants are studied covertly (secretly,
without the participant’s knowledge), and this means
that the researchers do not ask for consent. In this
instance, researchers may ask a similar group of people
to their participants whether they would be likely to
agree to take part. If those people say yes, then the
researcher may use this information to justify not
gaining consent from their actual participants.
Figure 0.46: Psychologists must gain the consent of
a child’s parent or guardian for them to participate
in research.
Researchers should ensure that they provide as much
information as is required to make a decision, in a way
that their participants are likely to understand. This
might mean providing information about the study
in another language, or in simplified language. When
working with child participants or people judged not
to have full capacity to consent to such decisions,
researchers will need to gain consent from parents or
guardians. It is important that the actual participants
also agree to take part, where possible.
By valid, we mean the consent is freely given, and they
are capable of understanding what they will be doing in
the study. There are some instances where participants
are less likely to be able to understand what they are
agreeing to, for example if the person is very young,
KEY TERM
Consent: voluntary agreement to participate
in research.
PSYCHOLOGY IN REAL LIFE
‘Children Online: Research and Evidence (CO:RE)’
is an international collection of research projects
exploring the experiences of children and
young people in digital communication. To help
researchers, CO:RE have developed resources
to ensure that research carried out with child
participants adheres to ethical guidelines.
they will be asked to do. For this reason, some
researchers on the project have designed a childfriendly, animated film which informs children about
their rights as research participants.
1
Can you think of why watching an animated film
might be helpful for children and young people?
One key guideline that can be challenging for
researchers is ensuring that children and young
people understand the aims of a study, and what
2
What else would the researchers need to do
to ensure they follow the ethical guideline
of consent?
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Debriefing
Debriefing happens at the end of the research. It is the
opportunity for researchers to thank participants and
give them the chance to ask any questions they may
have. The researchers can use the debriefing to more
fully explain the aims of the study, and also explain
whether there was any deception and why.
In some research it is unavoidable that participants could
feel upset or worried by their experience of the procedure.
For this reason, debriefing can be used to reassure
participants or include a task to do that would help
restore their mood to how they felt prior to the study.
Confidentiality
Confidentiality is the ethical guideline that relates to
the way in which participants’ personal information
is stored and shared. The names of participants and
their identifying details should never be published in
psychological research.
It is the responsibility of the researcher to store personal
information (such as names and contact details)
securely. This information should be destroyed after
it is no longer needed, in accordance with law around
data protection. Research data, including completed
questionnaires, transcripts of interviews or video
recordings should not be shared with individuals outside
of the research study.
Research Methods
MAKING CONNECTIONS
You may see some participants in the named
studies whose identities have been protected by
the researchers. For example, HM, the man with
amnesia in Chapter 1: Memory and Forgetting
is referred to by his initials only. In Chapter 6:
Language Development, the four young children
in the study on schemas and language (Hewitt),
are given different names.
Avoiding deception
Wherever possible researchers should ensure they
are avoiding deception in their research. This means
participants should not be deliberately misinformed
about the aims or procedure. This is not always possible,
as sometimes if participants are aware of the study in
full, it could change their behaviour or responses so
much that the results are not meaningful.
For example, if a researcher wanted to study whether
males or females are more helpful, they might need to
use deception. If they told participants the aim was to
compare levels of helpfulness, participants might feel
they need to be more helpful than they would in their
ordinary lives. This means the researcher would not get
a true representation of how helpful people are. For this
reason, they might tell the participants the study has a
different aim and create a scenario where the participants
have a chance to be helpful but do not realise this is the
behaviour really being measured in the study.
When it is necessary to use deception in a study, it is best
to do so only when it is unlikely to upset participants.
If participants are deceived, researchers should tell
the participants the true aim of the study as soon as
possible in the debrief and give them the opportunity
to have their data removed from the study’s findings.
Figure 0.47: Confidentiality can be maintained
through protecting participants’ personal data securely.
Researchers can use different methods to protect the
confidentiality of their participants. For example, they
can use fake names or initials for those involved in case
studies, change the names of a person’s workplace or
school and allocate numbers to questionnaire responses
instead of using participants’ names.
KEY TERMS
Debriefing: providing full information about the
research to participants once data is collected;
used to reduce any effects of deception.
Confidentiality: protecting personal information
of participants by keeping their data anonymous.
Avoiding deception: avoiding intentionally giving
wrong or incomplete information to participants.
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protected; they should be provided with an individual
physical space if undertaking research in a laboratory.
Similarly, in an observation, participants’ privacy can
be protected by only watching people in situations
where they are in public and would expect to be seen by
other people.
Minimising harm
Figure 0.48: Research into helpfulness might
require psychologists to use deception to obtain
accurate results.
Right to withdraw
Having the right to withdraw means that participants are
aware they are permitted to leave the study whenever
they wish. This right must be made clear to participants
at the beginning of the study.
Researchers must always consider the risk of physical or
mental harm when working with human participants.
Minimising harm is a key ethical guideline that can also
influence other guidelines. For example, we encourage
the right to withdraw so participants can avoid getting
distressed, and we gain consent to ensure participants
are comfortable with the tasks they will be undertaking.
Physical harm might include situations in which people
feel uncomfortable or even some minor pain. Examples
of this might include studies in which participants
have their sleep restricted or that use uncomfortable
equipment where they are unable to move around freely.
Sometimes, participants are offered incentives like
money or course credits to take part in research. If the
participant uses their right to withdraw from a study, it
is ethical to ensure they still receive the reward they were
offered. If a reward is withheld, this would put pressure
on the participants to continue when they do not want
to and is considered unethical.
Likewise, researchers should not use their position of
authority over participants to pressure them to continue.
Researchers should remind participants of their right
to withdraw, particularly if they think the participant
might be experiencing distress. This is an important
guideline to follow throughout the study, even if it
means losing the participant’s data.
Privacy
Figure 0.49: Equipment such as this MRI scanner may
be unsafe for researchers to use on certain individuals.
KEY TERMS
Respecting a participant’s privacy in psychological
research means respecting their physical and emotional
boundaries. Some research might require asking for
personal information or involve observing participants.
This should be kept to the minimum necessary for the
aims of the research.
Right to withdraw: participants are aware they
can leave the research at any time.
In a questionnaire or interview, the researcher should
make clear to participants that they can refuse to answer
questions if they want to, which helps protect their
privacy. The participant’s personal space should be
Minimising harm: participants are not exposed
to any greater physical or psychological risk than
participants may experience in their daily life.
Privacy: respecting participants’ personal space,
refraining from making participants reveal
unnecessary personal details.
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Psychological or mental harm includes situations
where participants are at risk of feeling embarrassed,
under stress or that lower their self-esteem. Examples
of this include studies in which people must recall
unpleasant memories or engage in mentally boring
or challenging tasks.
It is the researcher’s responsibility to consider any
and all risks their participants might experience when
conducting research and reduce these as far as possible.
To minimise risk of harm they may consider whether
any particular groups of people or individuals are
more likely to experience negative effects. For example,
a person with a physical health condition might not
be a suitable participant for a study that requires
vigorous physical exercise or to receive injections of
an experimental drug.
Research Methods
b
A researcher is conducting an observation to see
people’s preferences for personal space. What
steps should they take to meet these guidelines:
• privacy
• minimising harm
• debriefing.
19 A researcher wants to investigate the effects of
temperature on concentration. They plan to get
participants to put their faces in ice cold water for
15 seconds, and then ask them to undertake two
hours of a boring paper-folding task.
Explain how the researcher can improve this study
to meet the ethical guideline of minimising harm
for their participants.
Ideally, participants should not be exposed to any
greater risk within psychological research than they
would be in their normal everyday lives. If unexpected
threats to participants’ wellbeing arise during a study,
researchers should stop the procedure.
Applying knowledge of
ethical guidelines
To apply your knowledge of ethical guidelines to
novel scenarios, you will need to be able to recognise
the different guidelines and consider how they can be
applied by psychologists. You will also need to be able
to identify issues within real-life research which break
ethical guidelines and how these can be resolved.
Figure 0.50: Psychologists must give additional
consideration to ethical issues with using
prisoners as research participants.
Use the following questions to apply your knowledge
of ethical guidelines to novel scenarios.
KEY POINTS
Questions
18 Working in pairs, explain how the research in each
of the following scenarios should adhere to the
named ethical guidelines:
a
A researcher is conducting interviews with
people who have been in prison. What steps
should they take to meet these guidelines:
• consent
• confidentiality
• right to withdraw.
•
•
•
•
Ethical guidelines are used in psychology to
help protect research participants.
Psychologists must adhere to ethical
guidelines including gaining the consent from
those who wish to take part and debriefing
participants about the aims of the study and
any deception after the study is completed.
The confidentiality and privacy of participants
should be respected, and deception avoided.
Participants should be told about their
right to withdraw from the research, and
researchers must consider any risks to
participants to minimise harm.
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0.8 Role of the researcher,
materials and procedure
In this topic, we will look at the role of the researcher
when setting up and carrying out research. We will
look at how the researcher sets aims, designs materials
and organises the experimental conditions, all within
the ethical guidelines. We will also consider how data
can be collected and analysed. The preparation and
planning of a research study often takes much longer
and is a much more complex process than conducting
the study itself.
There are so many ways that research can be carried
out, using different methods and investigating different
areas of psychology. However, there is a standard
process that researchers follow and we are going to
look at the key aspects of the process in this section.
The flow chart in Figure 0.51 shows these aspects of
the research process:
Setting an aim
The first step in the research process is to set an aim.
This is usually a short sentence stating the purpose
of the research. The researcher will set an aim to
describe what they are intending to find out in their
study. The aim will usually start with a phrase such
as ‘to investigate…’. For example, a researcher who
is interested in the effect of playing video games
on quality of sleep might write an aim such as: ‘to
investigate the effect of playing video games on
quality of sleep’ or ‘to investigate whether or not
playing video games affects quality of sleep’. An aim
might also refer to the comparison of two (or more)
different variables so this researcher might have an aim
such as: ‘to investigate whether playing video games
or watching videos online has more of an effect on
quality of sleep.’
Set the aim of the research
(the purpose of the research)
Design materials
(such as stimuli, tests/tasks,
behavioural categories, questions)
Organise the experimental conditions,
observational setting, controls
Implement the ethical guidelines
Brief participants and give instructions
Conduct research and collect data
(such as experimental tests/tasks,
observations, questionnaires and
interviews and case studies)
Figure 0.52: An example of an aim is: ‘to investigate
the effect of playing video games on quality of sleep’.
All research should have an aim, whether it is an
experiment, an observation or a case study. Somebody
should be able to read the aim of a study and have
a reasonable idea of what the research is about.
However, the aim does not need to be specific or have
operationalised variables.
KEY TERM
Aim: the purpose of the research.
Analyse data
(including results and conclusions)
Figure 0.51: A flow chart showing the research process.
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ACTIVITY 0.19
Write an aim for each of the following topic areas:
1
Sugar intake and dreaming
2
Social support and stress
3
Singing and mood
4
Frustration and aggression
5
Fresh air and concentration.
Designing a procedure
•
•
•
Research Methods
If cameras are being used these will need to be
positioned correctly and they will need to be
checked to make sure they are working properly.
A one-way mirror may be used so this will need
to be set up.
The room that is being observed will need to be set
up with any necessary furnishings or equipment.
For example, when observing children’s playing
behaviour, a room needs to be set up with a variety
of age-appropriate toys and books. If observing how
teenagers work together when building a bridge out
of straws, a room is required that is big enough for the
number of participants and has plenty of straws and
other necessary equipment in it.
Once the aim of the research is set, it is time to design
the procedure. This means organising the experimental
conditions, the observational setting, and the controls
before the study can start.
In an experiment, the experimental conditions must be
organised to make sure each level of the independent
variable is tested appropriately and to ensure the
experiment runs smoothly. This may involve setting up
a room with appropriate equipment. For example:
•
•
•
•
chairs and tables
a screen or speakers
tasks on computers
questionnaires and pens on desks.
For example, when using a visual stimulus, it is
important to make sure that the correct stimulus
is set up and the screen is working properly. Any
technology needed must be switched on and tested to
make sure it is working properly. It is also important
to consider the setting of the experiment and to ensure
that lighting, noise, and temperature are all consistent
and comfortable for participants so they are not
extraneous variables.
Figure 0.53: More than one camera may be needed,
to ensure participants’ behaviour is recorded in all
parts of the room.
Another important part of organising the experimental
conditions is to plan which participants are going
to experience which condition and in which order.
It is also essential that the number of participants
experiencing each condition is considered, to make sure
all participants can be accommodated.
It is also important to put any necessary controls into
place. After identifying potential extraneous variables
and deciding on appropriate controls, these controls
need to be actioned. Controls may involve selecting
appropriate participants, such as participants of certain
ages or gender, or those with a certain background.
This may require potential participants to complete
questionnaires about certain traits they have so that
only those who meet the requirements are selected. For
example, if you are investigating the effect of increased
sugar intake on alertness, you would want to control for
conditions such as diabetes that might be dangerous for
a participant, or impact on the results.
For observations, it is equally important to make sure
the observational setting is organised. It is not always
possible to organise real-world settings, but if the
observation is going to be carried out in a laboratory
environment, this setting will need to be set up to meet
the requirements:
Some controls may relate to the environment of the
research setting, such as ensuring the temperature,
lighting, and noise level are consistent across conditions.
Other controls may relate to the materials being
used such as making sure the same word lists, maths
questions, puzzles or music are used for each condition.
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Another feature of an experiment that may be used is a
stooge (confederate). This is a person who is playing a
role in the research, without the participants’ knowledge.
The researcher will instruct the stooge how to behave
during the experiment. The behaviour of the stooge is
designed to manipulate the independent variable without
the participants’ knowledge. For example, if a researcher
wants to investigate helping behaviour, he may gather
participants in a room and ask a stooge to trip over
in front of the participants. The researcher can then
measure the participants’ responses. As the participants
do not know the person is a stooge, they will think a
person has really tripped over so the response they show
will represent how they would behave in real life.
a researcher may wish to investigate the effect of
different images on emotional response. They may
do this by presenting the stimuli, in this case different
images, to the participants (such as a calm beach, a busy
crowd, a rollercoaster, a scary monster) and measuring
the participants’ emotional responses either through
brain scans or self-report scales.
KEY TERM
Stooge (confederate): a person in the
experiment who is playing a role in the research,
without the participants’ knowledge.
Choosing materials
An important aspect of carrying out research is to
choose the materials that will be used. The quality of the
materials will determine the quality of the research itself
so it is essential for a researcher to think hard about
what materials they are going to use in their research
and how they are going to design them. There are many
different materials that can be designed for research.
Stimuli
Stimuli can be used in research in psychology.
Stimuli are any materials that cause a response in the
participant. Stimuli can apply to any of the senses so
can include: sights, smells, sounds, taste or touch.
Stimuli can be:
•
•
•
•
•
•
physical (an item or object)
audio (such as music or a sound)
visual (such as a film or picture)
irritants
pain
changes in temperature.
The stimulus (singular of stimuli) is presented to the
participants and the researcher observes the response of
the participants. This can be a fairly straightforward way
to measure the effect of something simple. For example,
Figure 0.54: A calm beach scene is an example of
a visual stimulus.
Tests and tasks
Tests and tasks are another type of material that a
researcher could design to use in their research. Tasks may
be designed for individuals (where a participant is asked
to complete the task on their own) or group tasks (where
participants are asked to work together in a group).
Examples of tasks include:
•
•
•
puzzles
computerised tasks
performing a speech or presentation.
A task may involve asking participants to carry out
an activity under different conditions. For example,
participants may be asked to carry out a tracking task
where they must follow a dot on a computer screen
using a cursor. This may be carried out in different
conditions such as after a good night’s sleep and after
a disrupted night’s sleep to see the effect of sleep
deprivation on concentration.
Tests can be designed by the researcher specifically
for the research they are carrying out, or they can be
established tests that have previously been created
and used by other researchers. For example, standard
tests already exist to measure IQ, different aspects of
personality and morality. However, simple tests such as
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memory recall and maths tests can also be used as a way
of measuring the effect of different conditions, such as
the effect of temperature on concentration.
Research Methods
combination of both. For example, a closed question
such as ‘Do you like the sun?’ gives us very limited
information because it will only lead to responses such
as ‘yes’, no, or ‘to some extent’, but is easy to analyse
the results. However, open questions such as ‘How does
sunshine affect your mood?’ or ‘How does the weather
affect how you feel?’ allow for more information to be
gathered, but the detail makes them harder to analyse.
(For more information on open and closed questions,
see Topic 0.3: Questionnaires and interviews.)
The researcher will need to decide how many questions
to use and what order to ask the questions in. Whatever
approach the researcher uses, it is essential that the
questions used gather the correct information and are
clear and easy for the participants to understand. For
example, if a researcher is investigating the effect of
sport on stress levels, questions would need to find out:
Figure 0.55: A computer tracking task is an example
of a task used in an experiment.
Behavioural categories
When carrying out an observation, behavioural
categories are important materials to design carefully.
(For more information on behavioural categories see
Topic 0.2: Observation.) Behavioural categories are
specific events or activities that the researcher looks
for in an observation, so they must be clear, objective
and observable. It is also essential that the behavioural
categories cover the behaviour that is being observed.
For example, if an observation is being carried out
to investigate children’s sharing behaviour there is no
point having behavioural categories such as ‘eating’ or
‘sleeping’. These may be behaviours that the children
carry out but these do not tell us anything about sharing
behaviour. In this case, behavioural categories would
need to include behaviour such as:
•
•
•
giving a toy to another child
taking a toy from another child
playing with the same toy with another child.
•
•
•
•
•
if the participant plays sport
how much sport they play
what sport they play
what their stress levels are
how their stress levels change before and after
sport and so on.
Figure 0.56: A questionnaire is one example of a
material that could be designed for research.
These behavioural categories are clear and specific
and tell us about the children’s sharing behaviour.
Questions
If a researcher is using a questionnaire or interview
in their research, the questions that they design are
very important. The researcher will need to decide if
they want to use open questions, closed questions, or a
ACTIVITY 0.20
Make a poster or slideshow showing the different
types of material that could be designed for
research in psychology. Show examples of each
of the different types of material.
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SELF-ASSESSMENT
Share your poster with a partner and discuss
what aspects of your knowledge and
understanding you are pleased with and any
areas you feel you could improve on. Make a
note of your thoughts and try to act on them
when you complete the next activity.
Ethical guidelines must be implemented to make sure
that participants:
•
•
•
•
agree to take part in the research
understand fully the aim of the research and their
role in it (even if this must occur after the study
has finished)
understand that their data is confidential
understand that they can withdraw themselves
or their data at any time
know where and how they can ask questions
or raise concerns
are protected from harm at all times.
Considering validity
and reliability
•
When conducting research, the researcher must ensure the
research is as valid and reliable as possible (see Topic 0.6
for more information on validity and reliability).
Before research can take place, it must be approved by
an ethical committee. An ethical committee is a group
of people who discuss a research proposal to see if they
think it is ethical and can go ahead. The ethical committee
might approve the proposal as it is, or they must suggest
changes that need to be made for the research to go ahead.
Valid research truly investigates what the researcher
originally aimed to investigate. This is made more
likely if the researcher can control extraneous variables,
meaning they can be confident that any changes in
the dependent variable are due to changes to the
independent variable. Valid research is also research
that is objective, meaning that it is not influenced by the
researcher’s own opinions or interpretations.
Reliable research has consistent measures or procedures
to collect data. This means that the research is carried
out in the same way for all participants, except for the
independent variable, which is changed. Inter-rater
reliability is also an important aspect of reliable research
because it refers to the extent to which two or more
researchers agree on their judgement of a participant’s
response to a situation. High inter-rater reliability means
that there is a high level of consistency between the
researchers, which means the results are more reliable.
Implementing ethical guidelines
A vital part of any psychological research is to ensure
that ethical guidelines are implemented at all times. (For
more information on ethical guidelines, see Topic 0.7.)
The main purposes of the ethical guidelines are to ensure
that all participants are protected from harm during the
research and that participants are informed about the
research as much as possible. As explained previously,
sometimes it is not possible to tell the participants
everything about the research in the briefing. If this is
the case the participants must be given a full and honest
explanation of the true aims of the research and the
participants’ role after the study is complete.
•
ACTIVITY 0.21
In pairs, discuss the type of research an ethical
committee might refuse and what sort of
amendments they might suggest to allow it to
go ahead. Think about the bullet point list above
describing the key purposes of implementing
the ethical guidelines and consider how these
can be met.
Briefing participants and
giving instructions
Before a participant can take part in a study they need
to be briefed and given instructions. A brief for a
participant should clearly explain:
•
•
the aim of the study
instructions: exactly what the study will involve
for the participant
• how long the research will take
• what to do if the participant has any questions
• the right to withdraw
• that any data collected is confidential.
When providing the aim of a study, sometimes it is
necessary to deceive the participant (to either lie or
to not tell the whole truth). This is because telling the
participant the true aim of the study could lead to a
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change in their behaviour and this could affect the
outcome of the study. In this case, the brief would
use a fake aim to cover up the true aim and therefore
minimise the change in behaviour of the participant.
For example, imagine you were investigating prosocial
behaviour by having a confederate (someone who is part
of the experiment) fall over to see whether the participant
would help them up or not. If you brief the participant by
saying ‘someone is going to pretend to fall over in front of
you to see if you will help them up or not’, this will clearly
change the participant’s behaviour. We can be confident
that most people would help the person up as they would
know they were being observed for prosocial behaviour
and would want to make themselves look good. In this
example the brief would instead need to say that the
study would involve the participant doing something else
unrelated, such as filling in a questionnaire or completing
a task. The fall could then be staged while the participant
is involved in the task which they think is the real study.
There are ethical considerations to take into account if
a brief involves deception: this is dealt with in detail in
Topic 0.7 on ethical guidelines.
Research Methods
Instructions that are given to the participant need to
be clear and easy to understand. A participant should
read the instructions and feel comfortable that they
know what is expected of them, what their role is, and
how long the study might take. Depending on the study,
instructions might be simple and straightforward such
as ‘complete the questionnaire using a black pen’. Or the
instructions may be longer or more complex if the study
requires more from the participant or there are several
stages to the study. For example, if the study requires
participants to complete a particular task in different
conditions and then to complete a questionnaire, the
different steps to the study would need to be explained.
If the task is computer-based or if specific equipment is
used, the brief may require more detailed instructions.
When briefing participants, they should be given a
chance to ask questions or to clarify anything they are
unsure about. Instructions for how to do this should be
provided in the brief itself. For example, participants
should be given contact details of the researcher in case
they have any questions or concerns after the study
takes place.
The brief should also explain participants’ right to
withdraw, which means:
•
they can choose not to take part in the study, or to
stop at any time if they are not happy.
After the study has ended, participants can choose to
withdraw their data if they decide they do not want their
results to be part of the research.
Finally, participants should be told that their data will
be kept confidential (their names will not be used and
the data will not be identifiable as belonging to them).
ACTIVITY 0.22
Here is a template for a brief:
The aim of this experiment is to...
In the experiment you will be asked to…
Next you will be asked to…
The experiment should last…
If you have any questions or concerns now…
Figure 0.57: When measuring prosocial behaviour,
it may be necessary to use deception to hide the
aim from participants.
Your data will be kept confidential, which
means that …
You have the right to withdraw…
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CONTINUED
If you have any questions or concerns after
the research…
Use this template and the information in this
section to write your own brief and instructions
for an experiment investigating the effect of
colouring on mood. The experiment will involve
participants rating their mood on a scale and
then colouring for 15 minutes and then rating
their mood on a scale again.
Figure 0.58: The effect of colouring on mood can
be measured by asking participants to rate their
mood before and after the activity, using a scale.
TIP
Critical thinking
A good way to check if your work is well written
or makes sense is to ask someone else to read it
for you. It can be difficult to spot errors or ways
to improve your own work so asking for someone
else’s opinion can be useful.
Conducting the research
and collecting data
Now it’s time for the research to be conducted!
Depending on the aims of the study, this research
may involve experimental tests / tasks, observations,
questionnaires and interviews, case studies or a
combination of these.
While conducting the research, the researcher must
always be aware of the ethical guidelines, and make
sure they are followed appropriately. For example, the
researcher must make sure the participants are protected
from harm at all times, and that they know they can
leave or ask questions at any time.
The researcher must also ensure that they give out
instructions carefully and accurately and that all aspects
of the research are conducted properly and within the
right order and time. For example, participants who
are asked to complete a test or task should all be given
the same instructions and the same amount of time to
complete the test or task.
Figure 0.59: Participants in research should always
be made aware that they can ask questions about
the research.
If an observation is being conducted the observers must
be informed about what they are looking for and how to
record their observations. If participants are being given
interviews, the interviewer must be fully prepared on
the questions they are asking and what (if any) further
questions or prompts they can give if needed. When a case
study is being carried out, the same applies to whichever
techniques are being used to gather information.
Collecting data is the key part of conducting the
research. Data collection will vary depending on the
research that is being carried out, but it is always vital
that data is collected accurately and stored in a safe and
organised way. This ensures that the data can be analysed
and compared later, and that conclusions can be drawn.
For the purposes of data collection, each participant
is given a unique number. This ensures that their
data can be linked back to them but keeps their
identity confidential.
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Research Methods
Data from research can take many forms:
•
•
•
•
•
If participants are completing a test / task then the
data collected may refer to the number of correct
answers, the number of errors, or the time taken
to complete the test / task. Answers or errors will
need to be counted carefully and accurately and
times will need to be recorded with a stopwatch
for accuracy.
If an observation is taking place, the observers
will need to have a way of quickly and accurately
recording their observations, such as a tally chart
for each behavioural category. Observations can be
carried out in real-time as well as through watching
video recordings at a later stage.
Collecting data from questionnaires can be
straightforward because the responses can be
collected through the use of paper or online forms.
Interviews, which can include a lot of information,
can be recorded so that data can be more
easily collected.
Case studies generate vast amounts of data that
need to be collected, whichever research techniques
are being used.
TIP
Data
When collecting data in research it is essential
that it is collected accurately, methodically and
confidentially. Using tables is a good way to keep
data structured and make it easy to refer back to.
Analysing data
Once the research has been conducted and the data
has been collected it is time to analyse the data. This
means comparing data between different participants
or different conditions.
Analysing data may involve:
•
•
•
identifying measures of central tendency and
measures of spread (for more information, see
Topic 0.9)
complex statistical analysis, where a researcher
carries out statistical testing to see if there are
significant differences between sets of data
using graphs, such as bar charts (for more
information, see Topic 0.9) as a way of visually
representing the data.
Figure 0.60: Visual representations of data, such as
graphs, form part of the results section in research.
The data that is collected and analysed in a study can
be found in the results and conclusions sections of a
research paper.
The results section is a summary of the data collected
in research, and analysis of that data. This can include
numerical data in tables, measures of central tendency,
measures of spread, further statistical analysis and
visual representations in graphs. This section also
includes a written summary of the data collected and
the findings from the data analysis.
The conclusion is a summary of what the researcher has
learnt from their research. It includes an interpretation
of any patterns in the data. This means looking at the
data analysis and summarising what the results show
(for more information on reaching a conclusion, see
later in this chapter). The conclusion also requires a
consideration of the research aim. This means looking
back at the aim, the purpose of the research, and seeing
what the data analysis shows. A conclusion may start
with the phrase: ‘it can be concluded that…’
For example, data analysis might show that 60-yearold participants take, on average, 55 seconds to solve
a maths puzzle, whereas 20-year-old participants take,
on average, 36 seconds to solve the same maths puzzle.
These average times would be reported in the results
section of a research write-up, along with further data
analysis. From this data analysis the research might
conclude that older people take longer to solve maths
puzzles than younger people. The aim of this research
may have been ‘to investigate the effect of age on ability
to solve maths puzzles’. The researcher might refer
back to this aim and conclude that age does affect the
ability to solve maths puzzles and that older people take
longer to solve maths puzzles than younger people.
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ACTIVITY 0.23
ACTIVITY 0.24
Discuss each of the following sets of results in
pairs. For each set of results, write a conclusion
that could be drawn:
Think of an area of research that interests
you: you could choose the same idea you
used for Activity 0.6 or choose something
different. Think about how you would carry
out your research. You are going to follow the
research process so write down your ideas for
each of the following bullet points for your
chosen research:
1
Average number of
errors in a driving test
Male
Female
7
3
2
Average turntaking in one
hour of play
Age
three
years
Age six
years
Age
nine
years
1
3
8
•
•
Write an aim.
Design materials for example, stimuli, tests/
tasks, behavioural categories, questions.
Organising experimental conditions, the
observational setting, controls: think about
any controls you need to put in place, and
consider the use of a stooge.
Implementing ethical guidelines: think about
what ethical guidelines you would need to
follow and how you would do this.
Write a brief for your participants.
Conducting the research: you will not
actually carry out the research but for this
section you could make up some results.
Analysing data: summarise your results and
conclusion, based on your imaginary results.
•
•
3
Number of
words correctly
recalled
Heavy
metal
music
playing
Classical
music
playing
Silence
•
•
8
8
8
•
Applying a researcher role
to novel scenarios
The process that a researcher follows when carrying out
research is complex and lengthy but is fairly standard.
The process can be applied when carrying out research
into any topic.
Questions
20 Explain what is meant by the term ‘aim’ and
write an example of an aim.
21 State three things that should be included in
a brief for a research participant.
22 Explain the difference between results
and conclusions.
KEY POINTS
•
•
Setting an aim involves writing the purpose
of the research.
Materials need to be designed; this
may include:
• stimuli to be presented: such as visual
or auditory
•
•
•
tests/tasks such as computer tasks
or memory recall tests
behavioural categories: observable
behaviours to be recorded during
an observation
questions to be used in questionnaires
or interviews.
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Research Methods
CONTINUED
•
•
Organising the experimental conditions,
observational settings and controls requires
the researcher to make sure all aspects
of the research have been carefully planned
and considered and the research is ready to
be conducted.
During the research it is essential to
implement ethical guidelines: participants
should be protected from harm at all times
and informed about the research before the
start of the research, participants should be
briefed and given instructions. This means
making sure the participant knows what the
research is about and what their role in the
•
•
•
Data tables
0.9 Dealing with data
In psychology, dealing with data is an essential part of
conducting any investigation. Data helps us to establish
what the experiment, observation, questionnaires,
interview or case study has actually found. With
data, researchers can make comparisons and draw
conclusions about their research.
Data can come in various different forms.
research is (as much as possible). Participants
should be informed of their rights and be
given the option to ask questions, raise
concerns or withdraw if they wish.
Next, the research is conducted, using
experimental tests/tasks, observation,
questionnaires and interviews and case studies.
Data is collected for analysis.
Analysing data involves carrying out statistical
testing on the data, summarising it in tables
and words, and representing it visually using
graphs. Conclusions can then be drawn from
the data, referring back to the research aim.
Data tables are one way to organise data in a structure
which uses rows and columns. These tables are often
used to allow researchers to easily compare participants’
scores or other results from an investigation.
Rows go horizontally across the data table, and
columns are vertical in the table. In an experiment, the
independent variable(s) (the variable being manipulated)
are typically listed in boxes in a column on the left, then
the dependent variable(s) are listed across the top row of
the table. Data points are then included in the table.
Title of data table
rows
Heading
Columns
Heading e.g. levels
of the independent
variable (units)
Sub-heading
e.g. dependent
variable
Sub-heading
e.g. dependent
variable
Data points are placed in
the appropriate cells of the table
Figure 0.61: Tables are useful ways of organising data collected in psychological research.
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Researchers will give a title to the data table which briefly
explains what the table is about. Each row and column
should be labelled with a heading, so that the data can be
correctly interpreted. Units should be included as a label
in the heading (and not put next to every single score).
Units are used to describe the measurement of data, such
as age (the unit could be years or months), time (units
could be seconds, days, months) or distance (units could
be centimetres, metres or kilometres).
Time spent on revision before exams
Student
Number of hours
for September
Number of hours
for April
1
10
18
2
23
43
3
24
27
4
7
8
5
0
30
Table 0.2: Example of a raw data table.
Mean vocabulary size
Children’s age
(years)
Nouns
Verbs
5
1 270
551
10
17 432
15 534
12
38 740
29 558
Table 0.3: Example of a summary data table.
Applying knowledge of data tables
This activity will help you identify and interpret data
from data tables in the real world.
ACTIVITY 0.25
Figure 0.62: Units of measurement such as time in
seconds should be indicated on data tables.
When a data table contains individual participants’ results,
this is called a ‘raw’ data table (Table 0.2). It is called this
because it does not contain any calculations or analysis. In
contrast, a ‘summary’ data table often includes measures
of central tendency or measures of spread. In other words,
it summarises the results of the group(s) of participants.
Summary tables often appear in the results section of a
psychological report (see Table 0.3).
KEY TERMS
Measures of central tendency: values that show
a typical score in a set of data.
Measure of spread: value that shows how similar
or different scores are in a set of data.
Data table scavenger hunt
Locate a data table of your choice (it does not
have to be related to a topic you are studying in
psychology). Good places to look for data tables
are in non-fiction magazines or journals, in print
or online newspapers. Try to collect at least three
examples of data tables.
Present the data tables to your class, explaining:
•
•
•
the purpose of each data table (you can
determine this by reading the title and labels
on the column and row headings)
one result from interpreting the data table
(this should be numerical)
one conclusion you can reach from the data
table (this should be a comparison between
data within the table).
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SELF-ASSESSMENT
What makes a ‘good’ data table?
This activity will help you think about how
you can improve your own data tables as you
create them.
Looking at the three data tables you found
in your scavenger hunt, what did you notice
about the different contexts where each
was used? Were they similar, or all used for
different reasons?
You can only calculate the mean from numerical data.
It takes into account all numbers in the data set. If the
data set is as in Table 0.4, you calculate the mean by
adding all the memory test scores together, then dividing
by 10 (the total number of data points):
Add all the memory scores together:
9 + 0 + 9 + 9 + 7 + 10 + 9 + 2 + 8 + 8 = 71
Divide by 10: 71/10 = 7.1
Participant
Memory test score
1
9
2
0
3
9
4
9
5
7
6
10
7
9
8
2
9
8
10
8
Consider the different styles and formats of data
tables that you collected. Would you say any are
clearer to interpret or more informative? Why?
Measures of central tendency
Measures of central tendency are statistical measures
that are used to describe the average of a set of data.
Researchers use these measures to identify a single value
that best represents the data set they are analysing.
Measures of central tendency can be used to summarise
and describe data collected in research studies.
We will consider the three most commonly used
measures of central tendency: the mean, median
and the mode.
KEY TERMS
Mean: the value calculated by adding all the
scores and then dividing by the number of values
or scores in the set of data.
Median: the value that appears in the middle of
a set of data, when arranged from the smallest
score to the largest value.
Mode: the value that appears most frequently
in a set of data.
Mean
The mean is the sum of all scores in a study, which is
then divided by the total number of data points in the
set. It is used to find the central value of a set and is
often what people refer to as the ‘average’.
Research Methods
Table 0.4: Memory test scores for participants.
Median
The median is the middle value of a data set, when
the scores are placed in numerical or ‘rank’ order. The
median is calculated by putting the data set in order of
scores from smallest to largest.
If the number of data points is odd, the median is the
middle value. If the number of data points are even, the
median is then the mean of the middle two numbers.
The median is a useful measure of central tendency to
use when the data set has some values that are at the
extreme ends of the data set (that is, very large or very
small). Using the data from Table 0.4, you can calculate
the median by placing all the values from the data set in
numerical order, then determining the central value:
Place all data values in numerical order:
0, 2, 7, 8, 8, 9, 9, 9, 9, 10
Determine the central value: 0, 2, 7, 8, 8, 9, 9, 9, 9, 10
Add together the two middle values: 8 + 9 = 17
Divide by 2: 17/2 = 8.5
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In this data set, the value of the mean is influenced by
the unusually low values of ‘0’ and ‘2’ and is calculated
as 7.1. However, most scores in the set are towards the
upper end of the ranking, so it is useful to also have the
information on the median score of 8.5.
Mode
The mode is the most frequently occurring score in a
data set. The mode is worked out by looking at a set
of data then identifying the most common value or
category. In Table 0.4, we can see that the score of ‘9’ is
the mode as it is the most frequent score in the data set.
While the mean, median and mode can all be used to
calculate central tendency for numerical data, the mode
is the only one of these measures we can also use to
calculate data that is in separate categories. Categorical
data is data which is not continuous (like numbers),
so it includes things like objects and events. If you
asked a group of people to vote on their favourite ice
cream flavour (strawberry, banana or chocolate) the
flavour is the category and you would be collecting
categorical data.
For this reason, a researcher may find that there is more
than one mode. An example of this is shown in Table
0.5. Because 32 people reported using sight and 32
people also reported using sound, ‘sight’ and ‘sound’
are both the mode for these participants.
Sense
Sight
Number of
people
32
Sound Taste
32
4
Touch Smell
28
26
Table 0.5: Number of people who reported
using each sense to identify an object.
Applying knowledge to select and
use measures of central tendency
To apply your knowledge of measures of central
tendency to novel scenarios, you must understand when
the mean, median and mode should be used to analyse
data. You must be able to explain how to calculate the
mode, median and mean using data that is unfamiliar
to you.
Try the Activity 0.26 to apply your knowledge of
central tendency.
ACTIVITY 0.26
Create a poster to show what is meant by central
tendency. Define what is meant by the mean,
median and mode. Include an example using data
you have made up for each measure. You could
use psychological areas of study from other topics
on this course to get ideas. Try to include images
linked to your examples, which will show how and
why each measure is used in different scenarios.
Some ideas might be data collected on:
•
•
•
the effect of sleep on mood
reasons people choose to exercise
differences in memory as people get older.
Measure of spread:
using the range
The range is a measure of spread (otherwise known as a
measure of dispersion). The range shows the difference
between values in a data set.
The range is calculated by subtracting the lowest score
from the highest score. For example, in the data set from
Table 0.4, the range is 10 − 0 = 10.
The range is a useful measure of spread for researchers
because it shows the extent of variety within the data.
However, it only considers two data points (the highest
and lowest) which means it does not reflect how often
those extreme values occur in the data set. For example,
the ‘0’ score is unusual in the data set from Table 0.4
because it only occurs once, and most other values are
towards the higher end of the data set.
Applying knowledge of the range
To apply your knowledge of a measure of central
tendency to novel scenarios, you must understand how
the range can be used to analyse unfamiliar data.
Try the following activity to apply your knowledge
of the range.
KEY TERM
Range: difference between the highest value and
the lowest value in a set of data.
58
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Research Methods
ACTIVITY 0.27
In assessing the performance of a sports team, the
range of scores in different games can indicate how
consistently or inconsistently a team performs.
Use the data in the table to calculate the range for
each team, Fusion and Hawks:
Match scores
Team
name
A
B
C
D
E
F
G
H
I
J
Fusion
23
15
10
13
16
12
16
17
22
14
Hawks
15
6
3
15
24
12
14
7
25
20
Title
y axis
Number of students
8
7
Bars
6
5
4
3
2
1
0
Scale
Favourite colours of students in the class
Categories
Orange
Green
Yellow
Red
Purple
Favourite colour
x axis
Figure 0.63: Bar charts offer a visual representation of data collected in psychological research.
Bar charts
Bar charts are one form of graph that can be used to
represent data. They consist of bars of different heights
that help researchers to compare the results from
different categories of data.
Bar charts are plotted on a set of axes. The horizontal
axis is called the ‘x-axis’ and the vertical axis is called
the ‘y-axis’. Just like data tables, labels and units are
required for each axis so that the information can be
clearly interpreted. A suitable title is also helpful to
indicate what the bar chart shows.
To create a bar chart, categories are typically listed
on the x-axis (in any order). The values are then listed
on the y-axis as a numerical scale. Bars are drawn to
represent the value of each category. When plotting the
bars, an equal space should be left between every two
consecutive bars (see Figure 0.64).
59
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Reaching a conclusion
Applying knowledge of bar charts
In the previous sections, you learnt about the different
components and purpose of bar charts. You can
practise applying this knowledge in different contexts,
including the practical creation of a bar chart, as well as
identifying results from existing bar charts.
You can create a bar chart to show data from a
questionnaire that you have conducted or use an existing
data set. Bar charts can be produced using software or
by hand, using graph paper, a pencil and a ruler. The
axes must be labelled correctly, and you should choose
an appropriate scale for the y-axis. Ensure the bars are
all of equal width and are properly spaced. Try Activity
0.28 to check you can apply your knowledge of creating
and interpreting bar charts in novel scenarios.
ACTIVITY 0.28
Imagine you have just completed a questionnaire
on students’ enjoyment of exercise by year
group. Using pencils, paper and a ruler, create
a bar chart using the information in the data
table below:
Type of activity
Team Individual Individual
sport
sport
exercise
Mean
Year 7
enjoyment
Year 9
rating
Year 11
(0-10)
4
3
2
9
1
4
9
4
8
PEER ASSESSMENT
Look at another student’s bar chart. Identify
two components of the work that are accurate
and appropriate to the task. Next, find one
improvement that you could suggest to the other
person to help them improve their work next
time. You might like to consider:
•
•
•
•
•
•
At the end of any investigation, the researcher will seek
to reach a conclusion after analysing their data. In a
conclusion, researchers interpret the measures of central
tendency and spread and help visualise the data using
tools like bar charts.
Conclusions always refer back to the aim of the study.
For example, if a researcher aimed to investigate the
times of year at which students revise the most, their
conclusion might be ‘students spend more time revising
at the end of their course than at the beginning’. This
conclusion should be supported by the data collected
through, for example, their questionnaires or interviews.
Any conclusion reached by a researcher must be wellsupported by factual data, which includes data tables,
the mean, median, mode, range as well as bar charts. The
conclusion is the researcher’s interpretation of this data.
Reaching conclusions from data
in tables and bar charts
To apply your knowledge of reaching conclusions
from data in tables and bar charts to novel scenarios,
you must be able to recognise that there are different
ways to display the same information, which can help
researchers make an interpretation.
Any data that can be displayed in a bar chart can also
be displayed in a data table. Bar charts can offer a
more visual or simpler way of noticing differences and
making comparisons. Complete the following questions
on a novel scenario about visual illusions to check your
understanding of how to apply this knowledge.
KEY TERM
Conclusion: interpretation of the patterns in data
to make a reasoned decision about whether the
results support the research aim.
how clear the labels are
whether units have been included
if the data is plotted correctly
that the bars are spaced apart
whether there is a suitable title
if the scale of the graph allows you to see
the data clearly.
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Research Methods
Number of participants
Questions
18
16
14
12
10
8
6
4
2
0
Perception of visual illusion by age
Old women
Young women
Children
Adults
Participant type
Figure 0.64: A bar chart showing the perception of the Leeper’s Lady visual illusion (see Chapter 4: Visual
Perception) by age
23 Identify the label on the x-axis.
24 State a result from the bar chart in Figure 0.64.
25 Outline a conclusion that can be reached from the
bar chart in Figure 0.64.
COMMAND WORD
KEY POINTS
•
When dealing with data, psychologists will
use data tables and bar charts to represent
their results.
Measures of central tendency including
the mean, median and mode as well as the
range as a measure of spread are used to
analyse data.
Once data has been analysed, researchers
can interpret the results to reach a
conclusion based on the aims of their study.
•
Identify: name/select/recognise.
•
KEY SKILLS EXERCISE
Knowledge and understanding
1
Without using this book or your notes,
see if you can outline what is meant by a
‘case study’. Check your answer and add
any detail that you missed.
4
Write a set of flashcards for the key terms
related to experimental methods. Work
with a partner or on your own to test your
knowledge of each term.
Define what is meant by the
following terms:
a
b
c
2
3
Experimental design
Repeated measures
Independent measures
Explain two ways to increase the
objectivity in research.
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CONTINUED
Application of knowledge
5
A researcher wants to find out whether
rewards help children behave better.
Give an operationalised independent
variable and dependent variable for
this experiment.
6
Sula is conducting research to investigate
the effect of temperature
on concentration.
a
b
c
d
e
7
What aim might Sula write?
What materials could she design?
What ethical guidelines should
she consider?
Write a brief that Sula could use.
Suggest some data Sula
might collect.
Oke is carrying out an observation into
the effect of watching comedy television
shows on mood. She is going to observe
her participants interacting with each
other, then watch a comedy show, and
then observe the participants interacting
with each other again. Oke is expecting
to find that interactions are more positive
after the comedy show. After carrying
out lots of research into this topic and
planning this observation for a long time
she feels very strongly about it. Oke has
asked her colleague Beth to observe
with her.
a
b
What should Oke consider in relation
to inter-observer reliability?
How can she try to reduce subjectivity
and increase inter-observer reliability?
L uca is observing people’s behaviour while
waiting for a train.
8
Using your knowledge of structured
observations, design a behavioural
checklist Luca could use. Try to include
at least two or three behaviours.
9
If Luca observes people’s behaviour via
CCTV/video recording, what type of
observation is he using? How could Luca
use overt observation instead?
10 Luca has collected the following data.
Identify the median of the data set and
write a short explanation about why your
answer is correct.
0
11
3
5
4
8
3
2
Analysis and evaluation
11 Why is a control group important in an
experiment? Use an example to illustrate
your answer.
12 Why is it important to have an aim and
a conclusion in research?
13 Why is it important to have research that
is valid and reliable?
14 Imagine you are the researcher from a
named study you have learnt about.
Write a short paragraph about how you
could follow three ethical guidelines
when conducting this research.
15 Identify one or more ethical problem(s)
with a named study you have learnt
about. Debate with a partner why
the researcher might have broken
ethical guidelines.
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Research Methods
SELF-EVALUATION CHECKLIST
How confident are you in each of the following areas?
Area
Very
confident
Fairly
confident
Not
confident
The features of experiments and their use in novel scenarios
Independent variable and dependent variables and their use in
novel scenarios
How and why variables are operationalised, including within
novel scenarios
Experimental design (independent measures and repeated
measures designs) including use within novel scenarios
What is meant by experimental conditions, including use in
novel scenarios
Experimental groups and control groups, including use in novel
scenarios
What is meant by extraneous variables and controls, including use
in novel scenarios
The features of observations and their use in novel scenarios
The features of a structured observation and an unstructured
observation and their use in novel scenarios
How and why behavioural categories are operationalised,
including in novel scenarios
The features of a covert observation and an overt observation
and their use in novel scenarios
The features of a questionnaire and use in novel scenarios
The features of an interview and use in novel scenarios
Open questions and closed questions, including use in
novel scenarios
The features of a case study and use in novel scenarios
What is meant by populations, samples and sampling technique
and their use in novel scenarios
Opportunity samples and volunteer samples, including use within
novel scenarios
What is meant by validity and how it applies to novel scenarios
What is meant by reliability and how it applies to novel scenarios
Ethical guidelines in psychology:
Consent, debriefing, confidentiality, avoiding deception, right to
withdraw, privacy, and minimising harm
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CONTINUED
Very
confident
Area
Fairly
confident
Not
confident
The application of ethical guidelines to novel scenarios
Understanding the process of research:
Aims of research
Designing research materials
Choosing experimental conditions, settings and controls
Validity and reliability
Ethical guidelines in research
Briefing and instructing participants
Conducting research and data collection
Data analysis
Conducting the research process in novel scenarios
Data tables and their use in novel scenarios
Measures of central tendency (mode, median, and mean)
including use in novel scenarios
Measure of spread (the range) including use in novel scenarios
Bar charts including their use in novel scenarios
How to reach conclusions from data, including from data in tables
and bar charts in novel scenarios
PRACTICE QUESTIONS
1 State what is meant by the term ‘experimental
conditions’.
[1]
2 Explain why it is important to identify extraneous
variables and control for them in an experiment.
[2]
3 Explain why it is important to implement ethical
guidelines while conducting research.
[2]
4 Describe what is meant by the following terms in the
context of dealing with data:
COMMAND WORDS
Describe: state the points of a topic/give
characteristics and main features.
Suggest: apply knowledge and understanding
to situations where there are a range of valid
responses to make proposals/put forward
considerations.
a
b
Mean
Median
c
d
Mode
Range
[4]
5 Suggest one closed question a researcher could include
in a questionnaire about TV programmes that people
watch.
[2]
6 Suggest how a researcher could collect an opportunity
sample from a target population of people aged 18–25.
[2]
References
Alhendi, O. (2019). Personality traits and their
validity in predicting job performance at recruitment:
a review. International Journal of Engineering and
Management Sciences (IJEMS) Volume 4., pp. 222–231.
British Psychological Society. (2021). BPS Code of
Human Research Ethics. Accessed at: inf180_2021.pdf
(bps.org.uk). 20 June, 2024.
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Chapter 1
Memory and
Forgetting
LEARNING INTENTIONS
In this chapter you will learn how to gain knowledge and understanding of, as well as apply, analyse
and evaluate:
•
•
•
•
•
key concepts of memory
Craik and Lockart’s Levels of Processing model of memory
Atkinson and Shriffin’s Multistore model of memory
motivated forgetting
the brain in memory and forgetting
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PSYCHOLOGY IN CONTEXT
Marketing and sales using the primacy effect
The primacy effect describes how we are more
likely to remember the first information we hear.
This is shown in the named study by Murdock (see
Topic 1.3), who asked participants to recall word
lists. Results showed that words at the beginning
of the list (primacy effect) and the end of the list
(recency effect) were more likely to be recalled
than those in the middle of the list.
shown. Li tested television viewers’ brand recall of
the adverts during the 2006 Super Bowl (the final
match of the National Football League in America).
Li found that the products advertised earlier in the
set were better remembered than those advertised
later. This information could be used by brands,
who may decide to pay more to get their adverts
shown earlier in a set of adverts, especially when
there will be a large audience.
The primacy effect can be used in marketing in
several ways:
Pushing certain products
The primacy effect can help companies encourage
customers to buy certain products. If there is a
range of products for sale, the company is likely to
want to encourage higher sales of more expensive
items, or newer products. Putting these items at
the beginning of a products list means customers
are more likely to remember and think about them,
and therefore are more likely to buy them.
•
•
•
pre-promotion of a product
advertising position
pushing certain products.
Pre-promotion
Pre-promotion involves ensuring the first
impression the audience has of a brand-new
product is positive. Pre-promotion usually involves
a build-up of suspense followed by a big reveal of
the new product. The product is showcased in a
high quality, luxurious way so the audience’s first
view of the product is positive. The primacy effect
demonstrates that this first impression is likely to
last, and potential customers will continue to see
the new product positively.
Figure 1.2: Companies often put more expensive
items at the beginning of a product list to
encourage sales.
Discussion questions
Discuss the following questions in pairs or small
groups then share your thoughts with the class.
1
Figure 1.1: Pre-promotion is often used to
advertise products such as cars and phones.
Advertising position
Research by Li (2009) shows that the primacy effect
is present when a set of television adverts are
2
Why is it important for marketing teams to
use psychological research?
How could the psychology behind advertising
position in television commercials be
applied to web searches and advertising
on web pages?
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Memory and Forgetting
CONTINUED
3
If you were creating a menu for a new cafe that
was opening, how might you use the primacy
effect to influence the design of the menu?
Work in pairs to create a menu for a new cafe,
using what you know about the primacy effect
to help you.
KEY TERMS
Primacy effect: when information presented
at the beginning is better remembered than
information presented at a later stage.
Recency effect: when information presented
at a recent stage is better remembered than
information presented at an earlier stage.
1.1 Key concepts
Memory
Memory refers to the way in which we process
information from the world around us to remember it.
There are several different models of memory, including
the Levels of Processing model of memory (see Topic 1.2)
and the Multistore model of memory (see Topic 1.3).
For information to be remembered, it must be encoded,
stored and retrieved so that we can use it.
Encoding refers to how we process information from the
outside world. The information that is available to us
can come from any of our senses: sight, sound, touch,
smell and taste. We then need to process this information
so that it can enter our memory in a usable way.
Storage refers to how information can be held in our
memory so that it can then be accessed later. Information
is stored in different ways depending on which memory
stores are being used and what sort of information it is.
Retrieval refers to the process where stored information
is then accessed so that it can be used at a later stage.
KEY TERM
Memory: mental processes of input, storage and
retrieval of information.
Features of a memory store
There are four main features of a memory store: input,
capacity, duration and access. These four features will all
differ between different memory stores. Throughout this
chapter you will learn more detail about these features in
the different memory models that are covered.
KEY TERMS
Input: incoming information that is processed
into memory.
Capacity: maximum amount of information a
memory store can hold.
Duration: length of time information can be
held in a memory store.
Access: ability to get information from a
memory store.
Input refers to how we process information so that it
can enter our memory in a usable way. Input involves
encoding information from the outside world. This
means it needs to be organised in a way that allows
it to be stored so it can be used at a later stage. Input
can happen in three ways: acoustically, visually and
semantically. Acoustic input means that information
enters the brain and is stored according to the way it
sounds (as if you were saying the word). Information
that is input visually enters the brain and is stored
according to the way it looks (as if you were seeing it).
Information that is input semantically means that it
enters the brain and is stored according to its meaning,
based on your knowledge of the world.
Capacity refers to the amount of information that can
be held in a memory store. This can vary from very
small to unlimited, depending on the memory store. The
amount that can be held is broken down into ‘items’,
and each item can refer to a digit, a word or a picture.
Information can be ‘chunked’ together to increase the
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capacity. For example, if you were asked to remember
six letters, this would be much harder to do than if
you were asked to remember a six-letter word. In both
instances, six letters need to be remembered, but if they
are chunked together to make a word, that is only one
‘item’ to be held.
b
t
k
e
b
c
u
6 items
Information
chunked
u
c
k
e
t
Duration refers to the length of time that information
can be held in a memory store. This can vary from less
than a second up to an entire lifetime. For example,
older people may still be able to remember going to
school, or when a younger sibling was born, even if it
was 80 or more years ago.
Access refers to how information in a memory store
is reached to be used. Once information has been
stored it will need to be accessed whenever it is needed.
Sometimes this can be automatic or very easy, such as
recalling your date of birth. Sometimes it may be very
difficult or take a long time to access information, such
as asking someone to recall the name of someone they
went to school with many years ago.
1 item
Figure 1.3: Chunking is an effective way of
remembering more information.
ACTIVITY 1.1
Match each of the following terms to the correct definitions. Note down the number of the key term
and the letter of its corresponding definition.
1 Memory
A How information is held in the brain, ready to be accessed again at a later stage.
2 Encoding
B The way in which we process information so that it can be stored and retrieved.
3 Storage
C The amount of information that can be held in a memory store.
4 Retrieval
D How we process information from the outside world so that it can enter our
memory in a usable way.
5 Capacity
E How the information in a memory store is reached to be used.
6 Duration
F The way we access stored information so that it can be used.
7 Access
G The length of time that information can be held in a memory store.
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1
TIP
Knowledge
Flashcards are a useful way of learning terms
and definitions. Write the term on one side of
the card and the definition on the other side,
and test yourself regularly. Carry the flashcards
around with you so you can use them when you
have a few spare minutes.
ing
od
Enc
Access
The amount of
information that
can be held in
a memory store.
Figure 1.4: Flashcards can help when learning
key terms and definitions.
Memory and Forgetting
Procedural memory is a type of long-term memory
involving knowledge of how to do things. This includes
knowledge of motor skills and actions that are learnt
through repetition, for example, how to ride a bike
or tie shoelaces. Procedural memory does not require
conscious thought so once they have been learnt, actions
can be performed automatically. This is useful as it
means attention does not need to be focused on the
task, therefore allowing focus on other things. Imagine
you are tying your shoelaces: you can answer questions
or have a conversation as you would not need to
concentrate on the shoelace tying.
KEY TERMS
Declarative memory: stored information about
facts or events that is consciously remembered
and recalled.
Procedural memory: stored information about
how to do tasks.
Types of memory
Declarative memory is a type of long-term memory, where
information is held for a long period of time. Declarative
memory includes semantic memory and episodic memory.
Semantic memory holds general knowledge and facts, for
example, knowledge of capital cities and maths equations.
Episodic memory holds personal experiences or events
in our life, for example starting a new job or going on
holiday. Declarative memory requires conscious recall.
This means that you need to deliberately bring to mind
the information as you need it. So if someone asked you
where you went on holiday last year or what the capital
city is, you would need to consciously and deliberately
think to get the answer.
Figure 1.6: Procedural memory includes knowledge
of how to do things such as brushing your teeth.
Forgetting
Forgetting refers to losing information that we once
held in our memory. It can be a gradual process or
can happen suddenly. Information can be completely
lost or it can be modified and recalled incorrectly or
incompletely. Information that is forgotten can be
KEY TERM
Figure 1.5: Episodic memory includes personal
events such as holidays.
Forgetting: inability to remember information
learnt previously.
69
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lost permanently or it can be remembered again with
the use of cues (information that helps us remember
something). For example, you might forget someone’s
name but if you are given the first letter of the name,
you can remember it again. In this example, the first
letter acts as a cue to help you find the memory you
thought was lost.
Two key types of forgetting are retrograde amnesia and
anterograde amnesia.
Retrograde amnesia is a type of memory loss where
you are unable to remember events from your past. For
example, someone with retrograde amnesia may not be
able to remember getting married or having children.
Retrograde amnesia often results from an injury or an
illness. It can be temporary or permanent and it has a
range of severity. This means some people are unable
to remember any past memories, and others are able to
remember some but not all past memories.
KEY TERMS
Retrograde amnesia: inability to remember
information learnt previously or past events that
happened before injury, disease or trauma.
Figure 1.7: Forgetting can be a gradual process or
it can happen suddenly.
Anterograde amnesia: inability to remember new
information after injury, disease or trauma.
PSYCHOLOGY IN REAL LIFE
Clive Wearing was a talented musician with a
wife and grown-up children. In 1985, Wearing
contracted a viral infection that attacked his central
nervous system, and since then he has been unable
to store new memories.
Wearing’s semantic memory (knowledge of the
world) and procedural memory (how to do things)
still work well. His musical talent is undamaged:
he can read, play and conduct music as well as
he could before his illness.
Clive Wearing’s short-term memory (STM)
continues to work well so he can hold information
for anywhere between seven and 30 seconds.
However, because of damage to the hippocampus,
which is part of the brain involved in transferring
memories from STM to long-term memory (LTM),
Wearing is unable to make new lasting memories
(anterograde amnesia).
Questions
1 What does the case of Clive Wearing tell us
about memory?
2 The research into Clive Wearing is a case study.
Explain one argument for and one argument
against a case study.
3 Would you consider there to be any ethical
issues with this case study?
This means that he forgets things quickly, so he is
unable to read or have a conversation. It is as if his
conscious awareness resets every 30 seconds.
Wearing also suffers from retrograde amnesia, the
loss of past memories. He remembers very little
about his life before his brain damage. He knows
he has children and a wife, but cannot remember
specific personal events. He remembers that he
was a musician but cannot remember any moments
from his career.
COMMAND WORD
Explain: set out purposes or reasons / make
the relationships between things clear / say
why and / or how and support with
relevant evidence.
70
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1
Memory and Forgetting
It is possible for someone to have both retrograde and
anterograde amnesia. This is called global amnesia.
ACTIVITY 1.2
Without using anything to help you, read each
statement and decide whether retrograde
amnesia or anterograde amnesia is the
best answer:
Figure 1.8: Someone with retrograde amnesia may
not be able to remember significant events such as
getting married.
Anterograde amnesia is a type of memory loss in which
new memories cannot be formed, but past memories
can still be recalled. For example, someone with
anterograde amnesia would remember events from years
ago, such as getting married, but would not be able to
remember a person they met or a holiday they went
on after developing the amnesia. At its most extreme,
anterograde amnesia can mean someone is permanently
unable to learn new memories. However, it is most
often temporary.
Anterograde amnesia can occur as a result of using
certain prescription drugs. It can also result from some
rare illnesses, or can be a sign of Alzheimer’s disease
(a disease that leads to memory loss over time: a type
of dementia).
1
This type of amnesia is usually a result of
injury or illness.
2
This type of amnesia results in forgetting
events from your past.
3
This type of amnesia could mean someone
would not remember the name of a
grandchild who is born after their diagnosis.
4
This type of amnesia can result from certain
prescription drugs.
5
This type of amnesia can be a sign of
Alzheimer’s disease.
6
This type of amnesia could mean someone
cannot remember their first job from years ago.
7
This type of amnesia results in the inability
to form new memories.
SELF-ASSESSMENT
Consider how easily you could answer each
of these questions. Rank yourself on a scale
of 1–3 where 1 is ‘very confident in identifying
retrograde and anterograde amnesia’, 2 is ‘quite
confident’ and 3 is ‘not confident’. If you were
unsure on many of them, or if you took a long
time to work out the correct answer, spend some
time revisiting the section of the book then try
this activity again another time.
Figure 1.9: The forget-me-not flower is often used as
a symbol in hospitals to identify Alzheimer’s patients
or wards.
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Questions
Define the following terms:
1
3
4
a
Input
b
Capacity
COMMAND WORDS
c
Duration
Define: give precise meaning.
d Access
Give one example of a procedural memory and
one example of a declarative memory.
2
Explain two differences between declarative
memory and procedural memory.
Briefly describe two different types of forgetting.
Describe: state the points of a topic / give
characteristics and main features.
KEY POINTS
•
•
Memory can be defined as the way in which
we process information so that it can be
stored and retrieved. Important aspects of
memory are:
• Encoding: how we process information
from the outside world so that it can enter
our memory in a usable way.
• Storage: how information is held in the
brain, ready to be accessed again at a
later stage.
• Retrieval: the way we access stored
information so that it can be used.
There are four key features of a memory store:
• Input: how we process information from
the outside world so that it can enter our
memory in a usable way.
• Capacity: the amount of information that
can be held in a memory store.
• Duration: the length of time that
information can be held in a memory store.
• Access: how the information in a memory
store is reached to be used.
•
•
Two types of memory are declarative and
procedural:
• Declarative memory: a type of long-term
memory involving information about the
world and personal experiences.
• Procedural memory: a type of long-term
memory involving knowledge of how to
do things.
Forgetting can be defined as losing
information that we once held in our memory.
Two types of forgetting are:
• Retrograde amnesia: a type of memory
loss where you are unable to remember
past memories.
• Anterograde amnesia: a type of memory
loss where you are unable to form
new memories.
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Memory and Forgetting
1.2 Craik and Lockhart’s
Levels of Processing
(LoP) model of memory
Three levels of processing
Craik and Lockhart proposed the Levels of Processing
(LoP) model of memory in 1972. The model is so
called because it explains how the depth at which you
process information at the time of input determines
how well the information is remembered. This means
a more in-depth analysis of information produces a
strong memory that lasts a long time and is easy to
recall. According to the LoP model, storage is just a
by-product of processing information. This means
that this model does not focus on different memory
stores but instead focuses on the process involved
in memory.
In structural processing, only the visual features of the
information are considered. For example, a word would
be processed only in terms of the colour it is written
in or the size of the letters. This is a form of shallow
processing because it does not involve very much analysis.
Structural processing will not result in a strong memory
and the information will not be very easy to recall.
According to the LoP model, input refers to the depth
at which the information is processed. The model
states that information is easier to recall if it has been
processed at a deeper level.
Capacity cannot easily be explained by LoP. It could
be that more information can be held if it is being
processed at a deeper level because we can use past
knowledge and rules to help us process information
more efficiently.
Duration is also determined by the level of processing.
This is because information that is processed at a deeper
level is more likely to enter long-term memory and will
last longer.
Access will be easier for information that has been
processed at a deeper level. The memory is stronger so
it is easier to retrieve it again when needed.
According to the LoP model of memory, there are
three levels of processing. These three levels fall on a
continuum (from one end of a scale to the other) from
shallow processing to deep processing.
In phonemic processing, only the auditory features of the
information are considered. For example, a word would be
processed only in terms of how it sounds, such as whether
it rhymes with another word. The memory for information
processed at the phonemic levels is deeper than for
information processed at the structural level. However,
phonemic processing is still a form of shallow processing
and will also not result in a very strong memory.
In semantic processing, only the meaning of the
information is considered. For example, a word would
be processed in terms of its meaning. This may involve
comparing it to similar words such as other words for
animals or names of countries. Semantic processing
is the deepest level of processing as it involves active
and meaningful analysis of the information, such as
connecting the information with previous knowledge.
This will result in a strong memory that is long-lasting
and easy to recall. Take the word ‘horse’ for example.
Coupled with a prompt asking if the word is an animal
(semantic processing), it would be much easier to later
recall the word than if the question only asked what
colour the word was written in (structural processing)
or if it rhymes with ‘course’ (phonemic processing).
Craik and Lockhart carried out two experiments
into levels of processing. Let’s look at their second
experiment as it investigates the effect that levels of
processing have on memory recall.
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Structural
Semantic
Phonemic
Shallow
processing
deep
processing
Figure 1.10: According to Craik and Lockhart, there are three levels of processing: structural, phonemic
and semantic.
STUDY SUMMARY
Levels of Processing (Craik and Tulving,
experiment 2 only)
Aim: to investigate the effect of depth of
processing on memory recall.
words. The participants identified the words in
the typed list they had seen in the first part of the
experiment. This recall test was the measure of
memory performance.
Participants: 24 college students, including
males and females
Results:
Procedure: participants in the study were
presented with a series of 60 common five-letter
words. They read a ‘yes / no’ question about each
word to prompt processing at one of three levels:
structural, phonemic or semantic. The questions
were presented in a random order.
Structural processing: participants were instructed
to focus on the physical appearance of the word,
for example, ‘Is the word in capital letters?’
Phonemic processing: participants were instructed
to focus on the sound of the word, for example,
‘Does the word rhyme with…?’
Semantic processing: participants were instructed
to think about the meaning of the word, for
example, ‘Would the word fit in the sentence?’
After processing the words at one of these three
levels, participants were given a typed list of 180
words: the 60 original words and 120 distractor
Argument for Levels of
Processing model of memory
An argument for the Levels of Processing model of
memory is the Levels of Processing experiment 2 by
•
•
Participants who had processed the words at
a semantic level had better recall than those
who had processed the words at phonemic or
structural levels.
Participants who had processed the words at a
phonemic level had better recall than those who
had processed the words at a structural level.
Conclusion: deeper processing of information
during encoding leads to better memory recall.
This provides evidence for the influence of
different levels of processing on memory.
CHILD
JEWEL
FLAME
Figure 1.11: Participants in the study were given
common five-letter words to remember.
Craik and Tulving (1975) (see named study). The findings
showed that participants who processed the words at a
deeper level (semantic processing) had better recall than
participants who processed the words at a shallower
level (phonemic and structural). The deeper analysis
of the words during semantic processing meant that a
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1
stronger memory could be made so the words were easier
to recall. The more basic processing at the structural
level meant that a strong memory was not formed so the
words were difficult to recall. Phonemic processing led to
slightly better recall than structural processing because
the processing was at a slightly deeper level, although still
considered to be shallow processing. This study supports
the LoP model of memory because it shows that deeper
processing leads to stronger memories.
Argument against Levels of
Processing model of memory
An argument against the LoP model of memory is
that it cannot explain the limited capacity of memory.
The LoP model explains memory as being just a
by-product of information processing and does not
explain why only a certain amount of information can
be remembered at any time. This is in contrast to the
multistore model (see Topic 1.3: Atkinson and Shiffrin’s
Multistore model), which clearly explains the capacity
of memory and why it is limited. This is a weakness of
the LoP model of memory because it does not give us a
full and thorough explanation of all aspects of memory,
which limits how useful the model is.
TIP
Critical thinking
When writing arguments for or against a
theory, start by stating the arguments for or the
arguments against. Then explain this in more
detail by expanding or giving examples. Finish
by explaining why this is important.
Memory and Forgetting
PEER ASSESSMENT
After your small group discussion, join with
another group and share your thoughts. Consider
the points made by the other group. Write down
something you learnt from the other group
and something you would like to consider in
more detail.
Forgetting
The LoP model of memory can be used to explain
forgetting. Forgetting occurs when information that
was once learnt has been lost or, more likely, cannot
be retrieved. The LoP model of memory can explain
forgetting as a result of difficulties with retrieval. Cues
(hints or tips) can help with recall but the encoding
specificity principle states that these cues must be present
at both input and recall, otherwise forgetting may take
place. This means that, for a cue to help recall, it must
match the level of processing used at encoding.
For example, if you used structural processing at input
by saying that a word was written in red, a useful cue
to help recall would be one that told you the word was
written in red. However, a cue that told you the word
was a type of food would not aid recall and would likely
lead to forgetting because this cue is semantic, which
does not match the processing used at input. In the same
way, if you used semantic processing at input and said
that the word was a type of food, then a cue asking you
for a red word would not aid recall as the two levels of
processing do not match.
KEY TERM
ACTIVITY 1.3
Discuss the LoP model of memory in pairs or
small groups. Share your thoughts about the LoP
as a model of memory and consider the opinions
of others. What do you consider to be the
arguments for and against the LoP model? Does
it make sense to you? Can you think of any ways
it could be improved?
Encoding specificity principle: memory recall
is improved when the recall conditions (context,
cue) are the same as the encoding conditions.
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Input:
JEWEL
Input:
JEWEL
cue:
?
JEWEL
cue:
The word
is a type
of stone
The word
was written
in red
Figure 1.12: Cues can help with the recollection of information but only if the same level of processing is present
at encoding and recall.
Applying the Levels of
Processing model
LoP is a really useful model to know because it can
be used in real life whenever you need to remember
something. This could be when revising for exams, or
learning a new skill for a job, or even remembering
people you meet or places you have been. LoP explains
that deep, semantic processing leads to stronger
memories that are easier to recall so this can be used
when learning new information.
Here are some useful revision techniques that all require
semantic processing:
•
•
•
Figure 1.13: Levels of processing can help with
revision skills in real life.
When revising there are several techniques that can
help improve memory, all of which are based on LoP.
Explain a topic in your own words. Read through
this section then choose a friend or family member
that is not studying psychology and explain the LoP
model to them in your own words. This requires
you to use semantic processing to make sense of the
information in a way that has meaning to you and
this will lead to a stronger memory.
Use a mnemonic. A mnemonic requires using a
pattern of letters or a rhyme to help remember
the key features of a topic. For example, ‘My Very
Excellent Mum Just Served Us Noodles’ is a popular
mnemonic used to help remember the planets of the
solar system in order (Mercury, Venus, Earth, Mars,
Jupiter, Saturn, Uranus, Neptune) as the first letters
of the words in the mnemonic are the same as the
first letters of the planets in order from the Sun. This
requires you to use semantic processing as you are
remembering the key features of a topic by using
them to create a rhyme.
Apply information to a topic that means something
to you. Think of something that interests you or
is important to you and find a way of applying the
material to be learnt to that topic. This may also
involve attaching an emotion, which can also aid
recall. For example, if you are a fan of cars, think
about how the different levels of processing would
apply to remembering different cars.
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Memory and Forgetting
COMMAND WORDS
Compare: identify / comment on similarities and
/ or differences.
Give: produce an answer from a given source or
recall / memory.
Figure 1.14: Applying material to a hobby, such as
watching movies, can aid recall.
ACTIVITY 1.4
Use one of these revision techniques to revise the
section on levels of processing. After using the
technique, use a mind map to write down everything
you can remember about this topic. Compare your
mind map with the information in this section to see
how well the technique worked. Perhaps try another
technique with a different section in the chapter and
see which one works best for you.
Questions
5
6
7
Give the three different levels of processing in the
LoP model of memory.
Suggest a question that could be asked to prompt
each level of processing for the word ‘table’.
Using a lab study and word lists, suggest how
psychologists could test levels of processing.
KEY POINTS
•
•
•
The levels of processing (LoP) model of
memory describes memory as a by-product
of information processing. Shallow processing
leads to weak memories, which are hard
to recall. Deep processing leads to strong
memories, which are easier to recall.
There are three different levels of processing:
• Structural processing: a shallow level
of processing where information
is processed only according to its
visual features.
• Phonemic processing: a shallow level of
processing where information is processed
only according to its auditory features.
• Semantic processing: a deep level
of processing where information is
processed only according to its meaning.
Named study: Craik and Tulving’s Levels of
Processing experiment 2:
• Participants were asked a question about
a set of words to prompt processing at
one of three levels: structural, phonemic
or semantic.
•
•
•
•
Participants were then asked to identify
the words from a longer list of words.
• Semantic processing led to best recall,
followed by phonemic, with structural
processing leading to poorest recall.
• This study supports the LoP model of
memory because it shows that deeper
processing leads to better memory recall.
Evidence for the LoP model of memory comes
from Craik and Tulving’s Levels of Processing
experiment 2. Evidence against the LoP model
of memory is that it cannot explain the limited
capacity of memory.
The LoP model of memory can explain forgetting
in terms of the encoding specificity principle. If
the same cue is not present at both input and
retrieval forgetting can occur. For example, if you
input information through structural processing
and receive a cue for retrieval based on semantic
processing forgetting is likely to occur.
Knowledge of the LoP model of memory
can be applied to real-life scenarios such as
effective revision techniques.
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Sensory
register
Attention
Short-term
memory
Transfer
Retrieval
Long-term
memory
Rehearsal
Figure 1.15: The Multistore model of memory by Atkinson and Shiffrin (1968).
1.3 Atkinson and Shiffrin’s
Multistore model (MSM)
Atkinson and Shiffrin proposed the Multistore model
(MSM) of memory in 1968. The model gets its name
because it describes memory as being made up of
three separate stores. The three stores are: sensory
register (SR), short-term memory (STM) and
long-term memory (LTM). Information can be
held in each of these stores in different ways, in
different quantities and for different lengths of time.
Information can also be transferred between the
memory stores when required.
Sensory register
Figure 1.16: The sensory register stores information
about sight, sound, smell, taste and touch.
The sensory register is where information from
the senses is stored. Information from each of
the five senses (sight, sound, smell, taste, touch) is
stored in the sensory register and is input in a
modality-specific way. This means that sight
information enters the sensory register and is stored
as sight, sound information enters the sensory register
and is stored as sound and so on.
The capacity of the sensory register is huge: vast
amounts of information can be held here as a result of
all of the things your senses are currently experiencing.
However, the duration of the sensory register is very
short: information can only be held here for up to about
half a second. This means that most information held
in the sensory register disappears again before you have
even registered it.
However, if you pay attention to the information in the
sensory register, it moves into the STM and you become
aware of it. This means that you can now access the
information and can use it.
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Short-term memory
Information is temporarily held in STM and can be used
briefly before it is either forgotten or transferred into
LTM. The input of information into STM is acoustic (as
a sound). The capacity of STM is thought to be between
five and nine items. Each item could be a letter, a
number, a word or a ‘thing’. Miller (1956) described the
capacity of STM as ‘seven plus or minus two’, meaning
that most people could hold seven items in their STM
but that some could hold two more or two fewer than
that (so between five and nine). The duration of STM is
around 30 seconds.
To access information, it needs to be rehearsed. This
is where information is repeated over and over again,
either to access it from STM or to transfer it to LTM.
This is called maintenance rehearsal. If, for example,
you ask someone for directions, you would need to write
them down quickly or keep repeating them over and
over, otherwise you could forget them.
Memory and Forgetting
to use a process called retrieval. This means that the
information needs to be brought back to our STM so
that we can use it.
Figure 1.18: A significant event such as having a
baby will enter long-term memory and last a lifetime.
The serial position effect
The serial position effect states that information
presented either at the beginning or at a later stage will
be remembered better than information presented in
the middle. This is often demonstrated using recall of
word lists. A list of words is presented to participants
and they immediately recall the words in the list. The
serial position effect shows that words at the beginning
of the list and words at the end of the list will be better
remembered than words in the middle of a list.
Figure 1.17: Rehearsing information from STM into
LTM ensures the information isn’t forgotten.
Long-term memory
Information that has been rehearsed into LTM has
the potential to stay with you for the rest of your
life. The input of information to LTM is semantic
(according to meaning). The capacity of LTM
appears to be limitless: it is impossible to measure
completely but research suggests that LTM can hold
all the information we could need it to. The duration
is also limitless: information held in the LTM can last
a lifetime. To access information from LTM we need
Figure 1.19: If you forget to bring your shopping list,
you might find that you only remember the items at
the beginning and the end of the list.
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The primacy effect describes how words at the beginning
of the list are more easily remembered because they can
be rehearsed from the STM into the LTM. This means
that when someone is asked to recall the list of words,
they can retrieve the earlier words from LTM.
The recency effect describes how words at the end of
the list are more easily remembered because they remain
in your STM and have not been displaced (pushed out)
by later words. This means that when you are asked to
recall the list of words you will be able to recall the last
words straight from STM.
The words in the middle of the list are more likely to be
forgotten because they have not yet been rehearsed well
enough to enter the LTM, but have been displaced from
STM by later words.
Murdock’s study investigates the serial position effect
and is described in the Study Summary.
Probability of recall
100%
80%
Primacy
The MSM can be used to understand forgetting. The
way forgetting takes place depends on which store the
information is being forgotten from. Information can
be forgotten from sensory register and STM through
decay. This means that the information can disappear
if it has not been processed in some way within the
store’s duration. For the sensory register, the duration
is approximately half a second, so decay happens to
any information that you have not paid attention to in
that time. For STM, the duration is approximately 30
seconds so decay happens to any information that you
have not rehearsed in that time.
Forgetting can also take place from STM through
displacement. This means that if you have more than
five to nine items (STM capacity) in your STM, the
earlier items will be pushed out by the newer items
and forgotten.
Finally, forgetting can take place from LTM, due to
access problems. Sometimes we forget things we once
knew, but this is likely to be because we are struggling
to get hold of the information, rather than that the
information is no longer there.
Recency
60%
40%
Murdock carried out an experiment to see if he could
find evidence for STM and LTM being two separate
stores, as the MSM suggests.
20%
0%
Understanding forgetting
1
2
3
4 5 6 7
Serial position
8
9
Figure 1.20: The serial position effect showing the
primacy and recency effect.
ACTIVITY 1.5
MAKING CONNECTIONS
The MSM explains forgetting through decay,
displacement and access problems. Throughout
this chapter you will learn more explanations
of forgetting. Compare MSM with other
explanations of forgetting. Do they contradict
each other or could they work alongside
each other?
Copy and complete the table with the information
you have for each store and each category.
Encoding
Capacity
Duration
Sensory
register
STM
LTM
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Memory and Forgetting
STUDY SUMMARY
Serial position effect (Murdock)
Aim: to investigate the serial position effect of
memory recall.
Participants: 103 psychology students, including
males and females.
Procedure: participants were presented with a list
of 10–40 common words. Each individual word
was read aloud to participants. Each word was
presented for the same amount of time.
Participants were then tested on their memory
recall. They had 90 seconds to write down as many
of the words as possible.
The test was repeated with the same participants
over a few days, using different word lists
each time.
Results:
•
•
•
The results of Murdock’s study showed
a primacy effect and a recency effect in
word recall.
The first three to four words at the beginning
of the list (primacy effect) and the final eight
words at the end of the list (recency effect)
were recalled the most.
Words in the middle position on the list were
the least recalled.
Conclusion: the primacy effect occurs because
participants have more time to rehearse and
transfer words from short-term memory to longterm memory. The recency effect occurs when
items are still in short-term memory and readily
available for recall. The findings support the theory
that the short-term and long-term memory stores
are separate.
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ACTIVITY 1.6
•
Working in pairs, plan and carry out your own
version of the study by Murdock:
•
•
•
•
Write a list of ten words.
Write your instructions. Make sure you are
clear about what the participants need to do.
Plan and practise your procedure.
Select your sample. Find roughly ten people
who are willing to take part in your study.
•
Record and write up your results. Draw a
table like the one shown here to record the
serial position of each word recalled by each
participant. Once all participants have been
tested, add up the total number of times each
word was recalled.
Draw a bar chart to show your results. The
x-axis is the serial position from one to ten.
The y-axis is the number of times the word is
recalled from one to ten.
Serial position
1
2
3
4
5
6
7
8
9
10
Participant 1
Participant 2
Participant 3
Participant 4
Participant 5
Participant 6
Participant 7
Participant 8
Participant 9
Participant 10
TOTAL
SELF-ASSESSMENT
Revisit the Research Methods section on tables and graphs (see Topic 0.9) and check you are happy with
the quality of your table and bar chart. Did you include all the necessary features? Did you draw them neatly
and accurately?
TIP
Data
When drawing a bar chart, be sure to always include a title and to label the axes. Use units where
appropriate. Draw the bar chart neatly and carefully using a pencil and a ruler for accurate measurements
and straight lines.
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Memory and Forgetting
REFLECTION
Consider Activity 1.6 and reflect on how you
worked in your pair.
•
•
•
Do you think you worked well together?
Did you take a lead role or let your
partner take the lead, or did you work
equally together?
Think about how you planned your study. Do
you feel that you approached it in a structured
and organised way? How could you have
improved the way you planned the study?
Argument for the
Multistore model
An argument in favour of the Multistore model of
memory is the evidence from the serial position effect
study by Murdock (1962) (see the Study summary).
The last words in the list being recalled (recency effect)
shows evidence for short-term memory. This is because
the words have only just been presented, so they are
still being held in STM and have not yet been forgotten.
The first words in the list being recalled (primacy effect)
shows evidence for long-term memory. This is because
these words were rehearsed into LTM and then retrieved
back into STM to be recalled. This supports MSM
because it provides evidence that STM and LTM are
two separate stores.
Figure 1.21: Reflecting on your way of working is
an important and useful skill.
Applying the Multistore model
Now you have an understanding of the MSM, you can
use it to explain different scenarios.
For example, if you were going shopping you might
approach it differently depending on the number of
items you needed to buy. If you were going to buy
20 items you would need to write a list because you
would not be able to remember all 20 items. This is
because 20 is greater than the capacity of STM (five
to nine items). If you only needed to buy four items,
you would probably be able to manage without writing
a list because you will not have exceeded the capacity
of STM. However, without a list, you would need to
rehearse the items to make sure they are not lost from
STM due to decay. You would probably need to repeat
them in your head on the way to the shop.
Argument against the
Multistore model
Evidence against the MSM is that it cannot explain
depth of processing. The MSM describes the process of
rehearsal (repeating the information over and over) as
a way of transferring information from STM to LTM
to remember it. However, the Levels of Processing
study by Craik and Tulving (see the Study summary in
Topic 1.2) emphasises the importance of the different
levels of processing in determining how well information
is remembered. The MSM is limited because it is too
simplistic and it cannot explain depth of processing.
Figure 1.22: A limited capacity in STM means that a
shopping list might be needed.
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ACTIVITY 1.7
Read the scenario and answer the question.
You are in a classroom and there are lots of posters
on the walls, lots of people in the room and lots of
birds and trees outside the window. Others in the
class are shuffling paper and talking to each other,
and the birds outside are singing. The teacher is
talking and pointing to a diagram at the front of the
class.
Using your knowledge of the MSM, particularly
your knowledge of the sensory register, explain
how you can focus on what the teacher is saying
and showing you, even though there are lots of
other sights and sounds around you.
Another example is if someone told you their name, you
could probably remember it. However, if they gave you
their phone number you would need to write it down.
This is because a name is only one or two items, so it can
be easily held in STM or rehearsed into LTM. However,
a phone number is several digits long so the digits at the
start of the phone number would be displaced (pushed
out) by the digits later on in the phone number.
Questions
8
Define the following terms:
9
10
11
12
13
a
Sensory register
b
Short-term memory
c
Long-term memory
State how information can be transferred from
short-term memory to long-term memory.
What is the input method for STM?
What is the duration of LTM?
Name the three ways of forgetting according to
the MSM.
Outline two differences between MSM and LoP
models of memory.
COMMAND WORDS
State: express in clear terms.
Figure 1.23: Your sensory register has access to
all sensory information around you.
Outline: set out main points.
KEY POINTS
•
The Multistore model of memory (MSM)
describes memory as being separated into
three different stores:
• Sensory register: where information from
the senses is inputted in a modalityspecific way. It has a vast capacity but with
a duration of up to half a second.
• Short-term memory: where information is
briefly held if it has been paid attention to.
The information is inputted acoustically,
the capacity is five to nine items and the
duration is around 30 seconds.
•
•
Long-term memory: information is stored
here if it has been rehearsed sufficiently
from STM. The information is inputted
semantically and the capacity and duration
are considered to be limitless.
The MSM can explain forgetting in terms of:
• Decay: where information can be lost from
sensory register after half a second or
from STM after 30 seconds if it is not paid
attention to or rehearsed.
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Memory and Forgetting
CONTINUED
•
•
•
•
•
Displacement: where information can be
lost from STM if more than five to nine
items enter STM.
Access problems: where information
can be forgotten if we cannot retrieve it
from LTM.
Named study: Murdock’s serial position
effect of free recall study
Participants were asked to free recall lists
of words.
Results showed the primacy effect, where
the first words in the lists were more likely
•
•
to be recalled, and the recency effect,
where the last words in the lists were
more likely to be recalled.
• This shows support for MSM as it shows
evidence that STM and LTM are separate
stores.
Evidence for the MSM comes from Murdock’s
serial position effect study. Evidence against
the MSM is that it cannot explain depth
of processing.
Knowledge of the MSM can be applied to
real-life scenarios such as shopping lists and
concentration in class.
1.4 Motivated forgetting
Low-res
For most of this chapter, the focus is on explaining
how memory works and how forgetting occurs when
something goes wrong. This topic focuses on forgetting,
and particularly looking at reasons why people forget.
The psychodynamic theory
of forgetting
The psychodynamic theory was developed by
psychologist Sigmund Freud in the late 1800s to early
1900s. The theory was built on by other psychologists
who agreed with his views. The basic assumption of
the psychodynamic theory is that behaviour can best be
explained by looking at the unconscious. Psychodynamic
theory states that all behaviour has a cause, even if the
reason is not clear. The psychodynamic theory proposes
that forgetting takes place if a memory is unpleasant or
upsetting. Humans are motivated to forget something if it
is painful or difficult to think about, as a way of removing
the pain or upset. Sometimes this motivated forgetting
can be conscious or deliberate. Usually, however, the
unconscious mind is responsible for forgetting these
painful memories, to remove them from our conscious
awareness. This is a very different approach to the other
explanations of forgetting discussed in this chapter.
In previous examples, forgetting occurs as a result of
illness, injury or a limitation of the memory’s capacity or
duration. According to psychodynamic theory, forgetting
has a purpose: to protect us.
Figure 1.24: Sigmund Freud proposed
psychodynamic theory.
KEY TERMS
Unconscious: thoughts and feelings a person
cannot bring to their awareness.
Conscious: thoughts and feelings currently in
a person’s awareness.
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The structure of personality
According to psychodynamic theory, the personality
is made up of three key components: the id, the ego
and the super-ego. The id and the super-ego ‘pull’ in
opposite directions and the ego’s role is to try to
balance them out.
The id continues to be a part of our personality
throughout our lives, but as the other two parts of the
personality develop, the id can be controlled to some
extent. Adults do not usually shout and cry to demand
food when they are hungry, even though our id will still
be driven by this need.
KEY TERMS
Id: innate part of the mind led by desire.
Ego: part of the mind that balances the id and
super-ego.
Super-ego: part of the mind led by moral and
societal standards.
Figure 1.26: A baby is led only by the id so it will
cry to demand its needs are met.
The id operates on the ‘pleasure principle’, which
is the idea that all needs and desires need to be met
immediately, regardless of the consequences. The id
is selfish and is not influenced by logic or conscience.
The id is unconscious so is not something that we can
consciously control.
The ego
Figure 1.25: The id, the ego and the super-ego make
up the structure of the personality.
The id
The id is the innate and impulsive part of our
personality. It is present from birth and demands
that all basic human urges, needs and desires are met
immediately. A baby is led only by the id so it is focused
only on its own needs and wants and does not consider
other people, or the impact its behaviour may have on
others. For example, when a baby is hungry it cries to
demand food and will keep crying until it is fed. It does
not consider that it should wait until its mother or father
have finished what they are doing or that they might be
sleeping in the middle of the night.
The ego is the rational part of the personality. It
develops from the id when a child is a toddler, usually
between two and three years old. The ego is the
conscious part of the personality; it is the part of
ourselves that we are aware of.
The role of the ego is to try to meet the demands of the
id but in a way that is reasonable and acceptable. The
ego understands that sometimes it is necessary to wait or
take turns or compromise, but that the demands of the
id still need to be met. For example, a three-year-old may
complain if they are hungry but will usually be able to
wait if a parent explains that they will get them a snack in
five minutes. Or, a three-year-old may want to play with
a toy but is starting to learn that they must share and
take turns with others. This is in contrast to a one-yearold (in whom the ego has not yet developed) who may
just snatch a toy they want from another baby without
considering the consequences or the impact on others.
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Memory and Forgetting
guilt or that they will be in a lot of trouble if they
accidentally break a plate. This means that if you
behave in a way that isn’t perfect, you may experience
guilt. The super-ego will try to make the ego focus
purely on making moral decisions rather than the
more sensible realistic compromise that the ego will
usually take.
Figure 1.27: A three-year-old takes turns because
their ego is developing.
The ego operates on the ‘reality principle’, which is
the idea that there needs to be a sensible, rational and
realistic way of meeting the needs of the id. The reality
principle takes into account the feelings of others, rules
and norms of society and compromise.
The super-ego
The super-ego is the last part of the personality to
develop roughly between three and five years old.
The super-ego is driven by moral standards and values,
which are learnt from our parents and other influences
around us. Although we are aware of the moral
standards of society, the super-ego is unconscious and
can be driven by values that we are not consciously
aware of. The super-ego is so focused on morals and
doing the right thing that sometimes the standards
can be too high. For example, a child may be so driven
by their super-ego to be perfect that they feel extreme
Figure 1.28: The super-ego develops around 3–5
years old and can lead to extreme feelings of guilt.
The super-ego follows the ‘morality principle’, which
means that it is driven purely by a desire to do the
right thing and to follow moral standards. Although
this is an important part of our personality and people
should aim to behave in a good way, the super-ego can
go too far in this direction, without the ego fighting
back. For example, if your friend is hungry and you
have a snack your super-ego may be driven to give
the whole snack to your friend, leaving you hungry.
Instead, your ego would balance this out by sharing
your snack with your friend.
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ACTIVITY 1.8
Copy and complete the table. For each scenario, consider how the id, the ego and the super-ego
might behave:
Id
Ego
Super-ego
You walk past a shop and see an
expensive pair of shoes you love.
Someone pushes in front of you
in a queue.
A friend forgets to meet you for
a planned lunch.
You are very hungry but you are
in a study session that has gone
on longer than planned.
PEER ASSESSMENT
Extension task: create your own scenario and ask a classmate to consider how the id, ego and super-ego
would respond. Read their responses: do you agree with them? Discuss with your classmate and suggest
any alternative responses.
The parts of the mind
According to psychodynamic theory, there are three
parts of the mind: the conscious, the pre-conscious and
the unconscious.
KEY TERM
Pre-conscious: thoughts and feelings a person
is not currently aware of, but can easily bring to
their awareness.
unconscious is beyond our conscious awareness, it still has
a significant impact on our behaviour. Psychodynamic
theory states that the unconscious affects our behaviour
without us knowing, in many different ways:
•
•
•
•
•
•
The conscious is the part of the mind that we are aware
of and can speak about. It contains thoughts and
feelings and memories.
The pre-conscious is the part of the mind that we are
not currently aware of but that we can easily bring to
mind. It contains memories and information that can
be accessed when needed.
The unconscious is the part of the mind that is beyond
our conscious awareness. Freud suggests that the
unconscious is the largest and most influential part of
our mind. This contains thoughts, feelings, memories
and urges that are unpleasant or upsetting. Although the
difficulties in relationships with others
prejudice or negative attitudes to others
unhealthy habits
upsetting dreams
problem or antisocial behaviour
Freudian slips: where you accidentally say the
wrong thing. Although we might just consider this
an accident, Freud would argue that this is your
unconscious influencing you. For example, if you
accidentally said ‘cake’ when you meant to say
‘fruit’ this is a Freudian slip that suggests that you
unconsciously want to eat cake.
Freud described the three levels of consciousness as
being like an iceberg:
•
•
•
conscious: the part of the iceberg above the surface
pre-conscious: the part of the iceberg just below the
surface but still visible
unconscious: the largest part of the iceberg, unseen
below the water.
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KEY TERMS
Conscious mind
Preconscious
mind
Unconscious
mind
Figure 1.29: The iceberg is used by psychodynamic
theory to show the conscious, pre-conscious
and unconscious.
Defence mechanisms: protective behaviours
by the ego to reduce anxiety caused by conflict
between different structures of personality.
Repression: unconscious removal of emotionally
painful experiences and unacceptable thoughts
and feelings from consciousness.
Suppression: conscious removal of unpleasant
experiences and unacceptable thoughts and
feelings from consciousness.
us from feelings of guilt and anxiety that these memories,
thoughts and feelings may cause. By repressing a
memory, thought or feeling into the unconscious we are
not consciously aware of it so it cannot cause us harm.
To some extent, repression is helpful as it can work to
remove distress after an upsetting incident. For example, if
someone suffered a traumatic experience, repression would
mean that they would not have to experience the upset or
trauma of reliving or remembering the experience.
The role of defence
mechanisms in forgetting
The ego’s job is to balance out and control the
conflict between the demands of the id (‘I want, I want,
I want!’) with the demands of the super-ego (‘I should,
I should, I should!’). This can be a very difficult task,
and sometimes the ego is too weak to fight against the
strong-willed id or super-ego. When this happens, the
ego can use defence mechanisms to help protect itself
and reduce anxiety caused by the conflict.
There are many different defence mechanisms, which
all work in slightly different ways. Many defence
mechanisms are unconscious but some are conscious.
However, they all have the same intention: to protect
our ego from anxiety or upset. Two of those defence
mechanisms are repression and suppression.
Repression
Repression is an unconscious defence mechanism. It
involves removing emotionally painful experiences
and unacceptable thoughts and feelings from the
consciousness. The purpose of repression is to protect
Figure 1.30: Repression involves removing
emotionally painful experiences from the conscious.
However, there are problems with repression because a
repressed memory, thought or feeling can still influence
behaviour, even without us knowing. For example,
if someone close to you died during childhood but
this traumatic memory was repressed, you may grow
up to be anxious in future relationships due to the
unconscious fear of losing someone. Repressing a
difficult thought or feeling can also be unhelpful because
if you are not consciously aware of it you are not able to
process and understand it. This means that you will not
be able to overcome or correct the thought or feeling but
it will still have a negative effect on your life.
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Suppression
Suppression is a conscious defence mechanism, which
means there is conscious and deliberate effort not to
think about something that is upsetting. Suppression
involves blocking unpleasant or upsetting thoughts or
memories. For example, if someone suffered a trauma
and suffered from intrusive or persistent thoughts about
the event, they may use suppression to try to push
these thoughts away. Much like repression, the aim of
suppression is to protect the ego from anxiety or distress.
Suppression can be very helpful as it can allows people
to distract themselves with other things rather than being
overwhelmed or distressed by something unpleasant,
meaning they can continue with daily life. Suppression
tends to have less of a negative impact than repression.
This is mostly because it does not push the thoughts or
memories down into the unconscious: the person is still
consciously aware, but they are just reducing the amount
of upset the thoughts or memories can cause. However,
suppression can still have negative effects in terms of
causing stress, or preventing people from dealing with the
difficult thoughts, feelings or emotions.
Applying the psychodynamic
theory of forgetting
The key aspects of psychodynamic theory and how it
can explain motivated forgetting can be applied to a
range of scenarios.
Knowledge of defence mechanisms can also help us to
understand different scenarios. Someone who has had a
difficult time, for example, a friendship breakup or the
death of a loved one, may seem as if they are fine as they
are carrying on with school and activities as normal.
However, it may be that they are using suppression,
choosing to push the upsetting thoughts and feelings into
the unconscious, to protect themselves from the pain.
ACTIVITY 1.9
Read the statements and write down whether
each one best describes repression, suppression
or both:
1
It has less of a negative impact.
2
It is unconscious.
3
It is designed to protect you from harm.
4
It more often applies to traumas experienced
during childhood.
5
It is conscious.
6
It can still influence your behaviour.
7
It is controlled by the ego.
Questions
14 For motivated forgetting:
a
What is the name of the theory?
b
Who is the main psychologist?
c
When was the theory proposed?
15 Define the following terms:
a
Conscious
b
Pre-conscious
c
Unconscious
16 Give one positive effect and one negative effect of
using defence mechanisms.
KEY POINTS
•
•
The psychodynamic theory suggests that
humans can be motivated to forget to protect
themselves from upset.
The psychodynamic theory proposes the
structure of the personality:
• The id: the innate and impulsive part
of the personality, driven by wants and
•
needs without the consideration of
consequences or of others.
The ego: the rational part of the
personality, which humans are consciously
aware of, with the role of balancing out
the id and the super-ego and finding
sensible solutions.
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Memory and Forgetting
CONTINUED
•
•
The super-ego: the moral part of the
personality, driven by doing the ‘right’
and moral thing, in conflict with the id.
The psychodynamic theory proposes the parts
of the mind:
• The conscious: the thoughts and feelings
that humans are aware of at the time.
• The pre-conscious: thoughts and
memories that can be brought to
mind easily.
• The unconscious: thoughts, feelings and
memories that humans are unaware of but
TIP
Knowledge
When you are learning new information, such
as definitions, it is important to repeat the
information over and over and to test yourself
in different ways, such as speaking aloud and
writing the information down. The more time you
spend with new information the better you will
be able to remember it.
•
that still influence behaviour. The largest
and most influential part of the mind.
Defence mechanisms are used by the ego to
protect against upsetting thoughts, feelings
and memories:
• Repression: an unconscious defence
mechanism, where traumatic memories
are pushed down into the unconscious to
protect us from pain and distress.
• Suppression: a conscious defence
mechanism, where upsetting thoughts are
deliberately pushed away to try to protect
us from pain and distress.
Recent evidence for localisation comes from brain scan
research. This involves participants carrying out certain
tasks, such as recalling a past event, while being given
a brain scan. The results can show us which parts of
the brain are active during the task and therefore which
parts of the brain are responsible for this function.
Brain scans can also be used to investigate brain damage
in patients. If somebody has a stroke and is then unable
to remember past events, a brain scan can be used to
identify the area of the brain that is damaged.
knowledge
point
1.5 The brain in memory
and forgetting
Specific parts of the brain are involved in the processes
of memory and forgetting. They each have different
functions and are found in different locations.
Localisation of function
Localisation of function in the brain means that specific
parts of the brain are responsible for specific functions.
This means that memory, for example, is processed by
specific areas of the brain, such as the limbic system,
rather than being shared across the whole of the brain.
KEY TERM
Localisation: specific parts of the brain are
responsible for specific functions.
Figure 1.31: Brain scans provide evidence for
localisation of function in the brain.
Before brain scans were developed, the only way to
investigate which parts of the brain were damaged was
to carry out a post-mortem. This means that, after a
patient had died, the brain could be examined for signs
of damage. For example, if a patient had lost the ability
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to form new memories, a post-mortem may identify
damage to one or more areas of their brain. From this,
researchers could learn that those areas were likely to
be responsible for forming new memories. If several
patients all had similar symptoms and post-mortems
showed damage in the same areas of the brain it would
provide good evidence that these areas of the brain were
responsible for this function.
release of stress hormones and it then interacts with other
brain areas involved in forming memories. This leads to
strong emotional memories that can easily be recalled.
The limbic system
The limbic system is a part of the brain identified as
playing a key role in memory formation and memory
loss. The limbic system is located deep inside the brain,
just above the brainstem, and just below the temporal
lobes. It is a complex network of structures in the brain
and is involved in emotion, memory and learning.
amygdala
Figure 1.33: The amygdala is a small almond-shaped
structure in the temporal lobe.
Hippocampus
amygdala
hippocampus
cerebellum
The hippocampus is a small brain structure located in
the inner temporal lobe, and its curved shape is thought
to resemble a seahorse! You have two hippocampi: one
in each side of the brain, but they both do the same
job. The hippocampus is one of the most studied parts
of the brain and it has many important functions,
including the following roles related to memory:
Figure 1.32: The relative positions of the amygdala,
hippocampus and cerebellum.
•
•
Two key parts of the limbic system that are involved in
memory are the amygdala and the hippocampus.
•
•
Amygdala
One of the key roles of the hippocampus is in
consolidating memories from STM to LTM.
The amygdala is a small, almond-shaped structure in
the temporal lobe. The amygdala is involved in forming
and consolidating memories of emotional experiences.
Consolidation means making the memory stronger
so that it becomes permanent and is less likely to be
forgotten. When the amygdala is activated during an
emotional experience the memory is then consolidated
into long-term memory. Evidence shows that the more
the amygdala is aroused during an emotional experience,
the stronger the stored memory will be and the less likely
it is to be forgotten. The amygdala is activated by the
organising and storing new memories
attaching emotion to memories to make the
memories stronger
spatial memory and navigation
consolidating memories from STM to LTM.
Consolidation means making the memory stronger
so that it becomes permanent and is less likely to
be forgotten.
Although long-term memories are not stored in
the hippocampus, the hippocampus temporarily
stores information before transferring it to a longterm store. It is necessary for the memories to be
consolidated so that they are held somewhere other
than the hippocampus.
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Different types of memory are consolidated in different
ways. The hippocampus is particularly important for the
consolidation of declarative memories (semantic and
episodic). The hippocampus mostly works by ‘replaying’
memories to reactivate the neural circuits (brain activity)
associated with them. This strengthens the neural
circuits so the memories are stronger and less likely
to be forgotten.
hippocampus
Figure 1.34: The hippocampus is a seahorse-shaped
structure located in the inner temporal lobe.
Consolidation mostly happens when you are asleep,
so getting a good night’s sleep is really important. It
used to be thought that only certain stages of sleep
were needed for memory consolidation but more
recent research is mixed. It is now generally accepted
that all stages of sleep are important for memory
consolidation, with different processes happening in
the different stages.
Memory and Forgetting
MAKING CONNECTIONS
Sleep is important for memory consolidation as
it is when the hippocampus is most active. What
other important functions of sleep are there?
Consider this when you study sleep and dreams
in the next chapter.
Figure 1.35: Sleep has many important functions.
If the hippocampus is damaged, this can have a serious
impact on the ability to consolidate memories. The
hippocampus may be damaged by Alzheimer’s disease,
or through an accident, severe stress or depression.
Alzheimer’s disease is a form of dementia, which is a
condition where a person’s brain cells die off, leading
to a decline in memory and thinking skills. Damage
to the hippocampus can lead to a person being unable
to make new long-term memories, or being unable
to remember things that happened shortly before the
damage. However, they may still be able to remember
things that happened a long time ago. This can be
explained because the role of the hippocampus is not to
store long-term memories, but to transfer memories into
a long-term store. This means that if the hippocampus
is damaged, long-term memories are not affected as they
have already been consolidated and stored elsewhere.
However, because the hippocampus is damaged it is no
longer able to consolidate new memories into long-term
stores so these new memories are lost.
The hippocampus is one of the few areas of the brain
that can produce new cells, allowing the damage to
be reversed and memory skills to improve. There are
many ways that this recovery can be helped, including
exercise; brain-stimulating activities such as puzzles and
crosswords; and a healthy, balanced diet including lots
of fish and fruit.
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Cerebellum
The cerebellum is a part of the brain found just below
the cerebrum (the main part of the brain) and behind
the brain stem. It makes up about 10% of the volume
of the brain but it contains over half of the brain’s
neurons! The cerebellum has several functions including:
•
•
•
•
movement
balance
mental function
procedural memory.
Remind yourself of procedural memories by recapping
the section in Topic 1.1. Procedural memories are formed
when neural pathways are strengthened through repetition
of an action. Whenever an action is carried out, such as
tying shoelaces, certain neural activity happens in the brain.
Every time this action is repeated the same neural activity
occurs. The more the action is repeated, the stronger the
neural pathway becomes. Eventually, the pathways become
so strong that the actions can be carried out automatically,
without a person having to think about it.
The cerebellum is a key area in the brain involved in
storing procedural memories because it is responsible
for coordinating movement and fine motor skills. Fine
motor skills are movements involving small muscles,
particularly in your hands and fingers. This is necessary
for a wide range of skills in our procedural memory
such as tying shoelaces, drawing and writing. The
cerebellum receives sensory and motor information from
other parts of the brain and uses this information to
store movements into procedural memory.
Damage to the cerebellum can be caused by incidents
such as stroke, trauma, certain drug use or certain
illnesses. Damage to the cerebellum can be reversed with
treatment and rehabilitation, but this depends on the
cause and the severity of the damage. If the cerebellum
is damaged, this can result in reduced ability to learn
new skills and to perform previously learnt skills. For
example, someone with damage to their cerebellum may
no longer be able to write properly, or may be unable to
learn a new creative skill such as knitting. Procedural
memory relies on using motor skills, coordination and
predictions about the consequences of actions. The
cerebellum is responsible for all these skills so if it is
damaged, the ability to use procedural memory will
be impaired.
ACTIVITY 1.10
Produce a poster summarising the key facts
about the role of the brain in memory and
forgetting. Make sure you include the following
terms and their definitions:
•
•
•
•
•
localisation
limbic system
amygdala
hippocampus
cerebellum.
Be as creative and colourful as you like. Include
diagrams, facts and explanations as to how
each part of the brain is involved in memory
and forgetting.
REFLECTION
Think about how you made your poster and
consider the following:
•
•
•
•
cerebellum
•
Do you think your poster is creative?
Did you enjoy the creative side of the work?
Could you have done anything differently?
Do you think it helped with the task by
making the information more memorable
for you?
Do you think this a useful activity for other
parts of the chapter?
Figure 1.36: The cerebellum is located below the
brain stem.
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1
Memory and Forgetting
STUDY SUMMARY
HM amnesia (Milner et al.)
Aim: To investigate the role of the hippocampus in
recall and forming new memories.
Results:
•
Participants: ‘HM’, one 41-year-old male from the
USA who was experiencing amnesia.
Procedure: HM was studied 14 years after
undergoing brain surgery to help control seizures.
Most of his hippocampus and amygdala had been
removed during the surgery. Although the surgery
was successful in reducing his seizures, HM started
experiencing amnesia.
•
Researchers studied HM at a research clinic,
a medical centre and at his home. They also
reported the results of previous testing on HM
about his memory and intelligence.
•
FPO
Please replace Figure 1.38 with an FPO box
- CUPA will supply a replacement image at
2nd proofs.
Milner et al. carried out a case study on a patient, HM,
who had had his amygdala and hippocampus removed.
They were interested to see the effect that this had on
HM’s memory.
Argument for the role of the
amygdala and hippocampus
in memory
An argument for the role of the hippocampus in
memory is the case study of HM by Milner et al.
Tests showed that HM still had a normal
level of intelligence and was able to recall
childhood events but had difficulty recalling
experiences from one to two years before his
operation (retrograde amnesia).
HM’s ability to form new memories of people,
places and events that were new to him since
his surgery was severely impaired (anterograde
amnesia). For example, in the night, HM would
ask the nurse at the research centre how he
got there.
HM was able to form some simple memories.
For example, he showed a small improvement
over time in learning to solve a simple maze.
This indicated he may be able to learn, but
much more slowly and with more errors than
people without anterograde amnesia.
Conclusion: Brain damage can affect our ability to
form new memories and recall past experiences.
Evidence from this study indicates the importance
of the hippocampus and amygdala in memory
and forgetting.
(see study summary). The case study of HM provides
evidence for the role of the hippocampus and amygdala
in consolidation of memories from short-term memory
to long-term memory. This is because he had his
hippocampus and amygdala removed, and as a result
his ability to learn new memories was severely impaired.
This shows that the role of the hippocampus and
amygdala is to consolidate new memories into a
long-term store, as HM was no longer able to do this.
This supports the role of the brain in memory because
it shows that the hippocampus’ and amygdala’s
role is consolidation of short-term memory into
long-term memory.
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Argument against the
role of the amygdala and
hippocampus in memory
Evidence against the role of the amygdala and
hippocampus is that other parts of the brain are also
implicated in memory. Different parts of the cortex
have been implicated in different aspects of memory.
The cortex is the outer layer of the brain, and is
wrinkled in appearance, giving it a greater surface area
so more information can be processed by nerve cells.
The cortex is involved in many higher order functions
such as memory, thinking, learning and emotions.
For example, riding a bike can be a tricky thing to learn,
but the more a child practises this the easier it gets. Once
a child has learnt to ride a bicycle, they can then do it
without thinking. The cerebellum is involved each time
the child rides the bicycle. Every time they practise, the
same neural activity occurs and the neural pathway
becomes stronger. Eventually, with enough practice, the
pathways are so strong that the child can then ride a
bicycle without having to think about it at all.
Figure 1.38: The cerebellum is involved in learning
procedural skills such as riding a bicycle.
ACTIVITY 1.11
Figure 1.37: The cortex is the outer part of the brain.
TIP
Critical thinking
When evaluating a theory, it is useful to remember
that any evidence ‘against’ the theory is not
necessarily saying that the theory is completely
wrong. It might just mean that there are other
things to consider, and perhaps the theory is
limited or too simplistic to offer a full explanation.
Applying the role of the brain
in memory and forgetting
The role of the brain in memory and forgetting can be
applied to many different situations.
Maya has developed Alzheimer’s disease and
can no longer store new memories but can
remember events from her early life. Use the
following terms to explain what might be
happening in Maya’s brain:
•
•
•
•
hippocampus
store
consolidate
transfer.
Questions
17 Define the following terms:
a
amygdala
b
hippocampus
c
cerebellum
18 Summarise the findings of the named study by
Milner et al.
19 Explain the effect of damage to the cerebellum.
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Memory and Forgetting
KEY POINTS
•
•
Localisation of function in the brain means
that specific parts of the brain have
specific functions.
The limbic system is involved in memory
and forgetting. Two key areas involved in
memory are:
• The amygdala: this is involved in
consolidating memories of emotional
experiences.
• The hippocampus: this is involved in
consolidating memory by transferring it
to a long-term store.
• The cerebellum is involved in storing
procedural memories by strengthening
•
•
the neural pathways. Damage can lead
to an inability to learn new procedural
memories or access previous ones.
Evidence for the role of the amygdala and
hippocampus in memory comes from
Milner et al.’s study of HM. Evidence against
the role of the amygdala and hippocampus
in memory is that there are other parts of the
brain involved in memory.
Knowledge of the role of the brain in
memory can be applied to real-life situations
such as learning a new skill or explaining
Alzheimer’s disease.
KEY SKILLS EXERCISE
Knowledge and understanding
1
2
3
4
5
Without using this book or your notes, see
if you can outline the Multistore model
of memory in as much detail as possible.
Check your answer and add any detail
that you missed.
Write a list of three examples of
procedural memory and three examples
of declarative memory.
Complete a mind map on everything
you know about levels of processing.
Then, using a different colour pen, use
the section in this book to add any
information you missed out.
Name and define the three parts of the
mind, according to psychodynamic theory.
Describe what is meant by ‘localisation of
function’ in the brain.
Application of knowledge
6
A man suffered brain damage after
a motorbike accident. Following the
accident, he could recognise and
remember his friends and family and
could remember major events throughout
his life, as well as what he had done in the
days just before the accident. However,
he could not remember what had just
been said to him, and was unable to read
a book or watch television.
How could the Multistore model of
memory explain this?
7 Arthur has suffered a stroke and is waiting
for test results to come back. Using your
knowledge of amnesia, how could you
advise Arthur and his family in terms of
the possible outcomes for him?
8 A researcher has carried out a replication
of Craik and Tulving’s Levels of Processing
experiment 2. Write a short paragraph to
explain what results she might find.
9 One-year-old Greta is playing with her
five-year-old sister Liesl. Greta snatches
the doll that Liesl is playing with. Liesl lets
Greta keep the doll and finds another doll
to play with, but Greta then snatches this
doll as well. Using your knowledge of the
structure of the personality explain the
behaviour of Greta and Liesl.
10 Carla is learning to sew. Explain what
is happening in her brain while she
is learning to sew, and what Carla
can expect when she has done lots
of practice.
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CONTINUED
Analysis and evaluation
11 A researcher replicated the study by Craik
and Lockhart to study the effects of levels
of processing. The table below shows the
number of words recalled for each level
of processing:
Level of
processing
Number of words
recalled
structural
5
phonemic
8
semantic
12
12 Discuss with a partner the evidence for
and against the Multistore model of
memory and Levels of Processing model
of memory. Decide which you think is the
best model of memory and explain to
your partner why you think it is best.
13 Write an essay describing the role of
the brain in memory, including evidence
for and against the role of the brain
in memory.
Draw a bar chart to show these results.
SELF-EVALUATION CHECKLIST
How confident are you in each of the following areas?
Area
Very
confident
Fairly
confident
Not
confident
What is meant by ‘memory’
What is meant by ‘input’, ‘capacity’, ‘duration’, and ‘access’ in the
context of memory
Declarative and procedural memory
What is meant by ‘forgetting’
The Levels of Processing model of memory by Craik and Lockhart
What is meant by structural, phonemic and semantic levels
of processing
Arguments for and against the Levels of Processing model
of memory
Using the Levels of Processing model to explain forgetting
Applying knowledge of the Levels of Processing model of memory
The Multistore model of memory by Atkinson and Shiffrin
What is meant by sensory register, short-term memory, and
long-term memory
The serial position effect
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Memory and Forgetting
CONTINUED
Very
confident
Area
Fairly
confident
Not
confident
Using the Multistore model of memory to explain forgetting
Arguments for and against the Multistore model of memory
Apply knowledge of the Multistore model of memory
How the psychodynamic theory explains forgetting
The structure of personality: the id, ego and super-ego
The conscious, pre-conscious and unconscious
How the defence mechanisms can explain forgetting
Applying knowledge of the psychodynamic theory of forgetting
What is meant by localisation of function of the brain
The role of the amygdala, hippocampus and cerebellum in the role
of memory formation and memory loss
Arguments for and against the role of the amygdala and
hippocampus in memory
Applying knowledge of the role of the brain in memory
and forgetting
PRACTICE QUESTIONS
1 Define what is meant by the term ‘memory’.
2 aExplain the argument for the
[2]
3 Answer the following question:
Levels of Processing model of memory.
[4]
‘To what extent can the Multistore model give
an accurate explanation for memory?’
bExplain the argument against the Levels of
Processing model of memory.
[4]
In your answer, be sure to consider evidence
for and against the Multistore model.
[4]
4 Explain the psychodynamic theory of forgetting. [4]
5 Explain the role of the amygdala in memory.
[3]
References
Craik, F, and Tulving, E. (1975). Depth of processing and the retention of words in episodic memory. Journal of
Experimental Psychology: General, 104, 268–294.
Milner, B., Corkin, S. and Teuber, H.-L. (1968) Further analysis of the hippocampal amnesic syndrome: 14-year
follow-up study of H.M. Neuropsychologia 6, 215–234.
Murdock, B. B., Jr. (1962). The serial position effect of free recall. Journal of Experimental Psychology, 64(5), 482–488.
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CAMBRIDGE IGCSE™ PSYCHOLOGY: COURSEBOOK ANSWERS
Practice questions and sample answers have been written by the authors. In examinations, the way marks are awarded
may be different.
Most ‘Psychology in real-life’ answers are NOT to be taken directly from the CB material, they are from students’
opinions/discussions based on the CB material.
Coursebook answers
Chapter 0
2
Psychology in context
This activity is based on students’ opinions but
could include:
1
2
In the natural sciences like chemistry and
physics, researchers are not working with
human or animal participants. This means
that they might be less limited in what
they can study and how they design their
experiments. In psychology, you cannot
just do whatever you want to human beings
because they have rights and are sentient.
Biology might have some similarities or
cross-over with psychology, particularly
when parts of the brain and the nervous
system are studied.
There could be lots of different ways to
study the same topic. With the example
of how people interact on social media,
psychologists might look at the positive and
negative aspects, for example. They could
ask people’s opinions or what their attitudes
are towards different platforms. The
researchers could directly record people’s
interactions to allow them to see if they
behave differently in person or online. Other
suitable ways could include interviewing
people, conducting an experiment or
studying one individual in depth using a
mixture of several different tests and tasks.
Candidates might lie on questionnaires to
make themselves look more suitable for the
job, and not truly report their personality
traits and skills. If questionnaires have lots
of closed questions, it might be difficult
to make a judgment between candidates.
This is why interviews might be good to use
as well. Ethically, people might not want
to provide personal information on the
questionnaire so there is a risk to the ethical
guidelines of privacy. Recruiters should also
consider confidentiality and make sure the
respondents’ information is kept secure.
Psychology in real life
1
Watching an animated film might be helpful
for children and young people because
it can be child-friendly. It can contain
content, images and language that young
people can understand. They can watch the
video in their own environment where they
feel comfortable, which might help them
concentrate and understand the messages
better. An animated video might hold the
child’s attention more than speaking with
an unfamiliar adult researcher.
2
The researchers also need to make sure
they gain consent from the child’s parent or
guardian. This means sharing information
about the aim and procedure of the study,
so they can make an informed choice to give
their permission for their child to take part.
Psychology in real life
1
1
Recruiters for jobs use questionnaires to
help them hire people for specific roles
because they can select people based on
their skills and personality traits. The
questionnaires can be given to candidates
and, depending on the data collected, they
can be best matched with different job roles.
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Activity 0.1
1
2
3
The researcher wants to investigate the
effect of noise on memory. Participants are
given a memory task to do and noise level
is changed (for example loud music playing
compared to silence). The results of the
memory task are compared and the findings
allow the researcher to see whether noise
affects memory.
The researcher needs to control the time
of day of the experiment. For example, if
they carry out the ‘silent’ condition early in
the morning and the ‘noise’ condition late
at night, the time of day might affect the
results because participants may become
tired during the day and find it harder to
concentrate later on. They will also need to
ensure the memory task is not different for
each condition; if one task is harder than the
other, this would also affect the results. It is
important to control as many other aspects
of the experiment as possible to be confident
that any effects seen are due to what is being
manipulated, rather than anything else.
Participants could be given a memory recall
task, such as being given one minute to
memorise a list of words and then recall as
many of the words as possible. This task
could be carried out in a silent condition,
and in a noisy condition, such as loud music
playing.
1
IV: exercise, number of hours spent exercising
DV: stress - rating on a scale of 1–7. 1 being
not stressed at all, 7 being extremely stressed
2
IV: age, in years
DV: fitness, time in seconds to run 500 metres
3
IV: gender, male or female
DV: stress, rating on a scale of 1–7. 1 being
not stressed at all, 7 being extremely stressed
4
IV: sunshine, number of hours in the sun
per day
DV: happiness, rating on a scale of 1–7.
1 being not happy at all, 7 being extremely
happy
5
IV: screen time, number of hours of screen
time per day
DV: child’s intelligence, score on a children’s
IQ test
6
IV: confidence, rating on a scale of 1–7. 1
being not confident at all, 7 being extremely
confident
DV: achievement, percentage of correct
answers in a class test
7
IV: sleep, number of hours of sleep per night
DV: memory, number of words correctly
recalled from a list
Activity 0.2
Activity 0.4
1
IV exercise, DV stress
1
2
IV age, DV fitness
3
IV gender, DV stress
4
IV sunshine, DV happiness
5
IV screen time, DV children’s intelligence
6
IV confidence, DV achievement
7
IV sleep, DV memory
Activity 0.3
Operationalising can be carried out in many
different ways. Ensure operationalised variables
are specific and measurable.
2
Examples include:
Independent measures: 30 participants will
be randomly allocated to go to the gym for
one hour per day for a week and complete
the stress scale after each gym session. The
other 30 participants will do no exercise for
a week and will complete a stress scale each
day. Results of each group will be compared.
Repeated measures: 30 participants will
complete one hour at the gym per day for a
week and they will complete a rating scale
for stress after the gym each day. Then
those 30 participants will have a week where
they do no exercise per day and they will
complete a rating scale for stress each day.
The other 30 participants will do one week
with no gym and then one week with gym.
Results for participants will be compared for
each condition.
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2
Independent measures: 30 participants aged
20 years are timed running 500 metres. 30
participants aged 50 years are timed running
500 metres. Results in seconds are compared
between the groups.
time for a change in screen time to impact
intelligence).
6
Repeated measures: 60 participants aged
40 years are timed running 500 metres. Ten
years later the same 60 participants, now
aged 50 years, are timed running in
500 metres. Results in seconds are
compared between each participant, ten
years apart (this is not a very practical
approach so independent measures would be
more sensible).
3
Repeated measures: 60 participants who are
rated as ‘low’ in confidence based on a score
on a confidence test are given a class test
and the percentage score is recorded. The
same participants take part in a confidenceboosting course, then their confidence
score is tested again. Participants who
have an increase in confidence will be given
another class test and the percentage will be
compared to their percentage when they had
low confidence.
Independent measures: 30 male participants
and 30 female participants are given a
stress scale to complete and the results are
compared between the groups.
Repeated measures: Not possible in this
scenario.
4
Independent measures: During a day
with four or more hours of sunshine, 30
participants are given a scale to complete to
measure their happiness level. Another 30
participants are given a scale to complete to
measure their happiness level on a day with
no sunshine. Ratings are compared between
groups.
Repeated measures: during a day with four
or more hours of sunshine, 60 participants
are given a scale to complete to measure
their happiness level. The same 60
participants are given a scale to complete to
measure their happiness level on a day with
no sunshine. Ratings are compared between
participants.
5
Independent measures: 30 children who
spend five or more hours per day on screen
time are given an IQ test to measure their
intelligence. 30 children who spend one hour
or less per day on screen time are given an
IQ test to measure their intelligence. Results
between each group are compared.
Repeated measures: 60 children who
spend five or more hours per day on screen
time are given an IQ test to measure their
intelligence. The same children will then
spend one hour or less per day on screen
time and are then given an IQ test to
measure their intelligence. Results between
participants are compared. (this is not
practical as it would likely take a long
3
Independent measures: participants are given
a scale to rate their confidence level and
are assigned as ‘high’ or ‘low’ in confidence
based on their ratings. All 60 participants are
given a class test and the percentage score for
participants high in confidence and for those
low in confidence is compared.
7
Independent measures: 30 participants who
sleep for at least eight hours per night and 30
participants who sleep five or less hours per
night each complete a memory recall task and
the results between groups are compared.
Repeated measures: 60 participants who
sleep for at least eight hours per night each
complete a memory recall task. These
participants are then only allowed to sleep
for five hours per night and then complete
another memory recall task. Results between
participants are compared.
Activity 0.5
Examples may include:
1
EV: participants’ enjoyment of singing.
Control: only use participants who have
previously stated they enjoy singing.
2
EV: amount of exercise carried out by
participants. Control: ask participants
to record their exercise.
3
EV: birth order of the participants (youngest,
oldest, middle). Control: only use participants
who are in the same birth order, for example
only use oldest or only use youngest.
4
EV: sugar level of fizzy drink. Control:
only use diet fizzy drinks.
5
EV: age. Control: use participants of the
same age.
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6
EV: a condition that affects memory such as
Alzheimer’s disease. Control: check for presence
of Alzheimer’s disease before the study.
observed that day in the park. The
researcher can note down littering
behaviours on their phone or notepad.
3
Covert observations can be difficult to
achieve in practice as there is a risk the
observer may be noticed by participants.
The people in the park might notice
there is someone watching and recording
information about whether they litter or
not, and even change their behaviour if
they are being watched. Ethically, a covert
observation can break the ethical guidelines
of gaining informed consent as people have
not agreed to be observed in the park.
4
If the observation was overt, people might
change their behaviour. For example, they
might be more likely to put their rubbish
in the bin than litter as they know they are
being watched. This would lower the validity
of the observation.
Activity 0.6
The design of the experiment should be based on
students’ own ideas, but each heading provided
should be addressed. In addition:
•
Variables should be operationalised correctly.
•
Experimental design should be practical
and logical.
•
Extraneous variables should be appropriate.
•
Control should be sensible and practical.
Activity 0.7
The answers to this will relate to the animal the
student has chosen to observe, how long they
observed for and how many behaviours they
were able to record.
1
2
Challenges could include: missing
behaviours as the student was writing others
down, difficulty describing a behaviour
during the observation, not observing for
long enough to see many behaviours or
observing for too long a period and not
being able to record all the data accurately.
This activity is based on students’ original
design but could include behaviours like
rolling, making sounds, licking themselves /
self-cleaning behaviours, interacting with
other animals, eating, drinking, pouncing
etc. The checklist should include a minimum
of three behaviours and be structured
in a grid with space to ‘tick off’ or tally
behaviours as they are observed.
Activity 0.9
Fixed response questions with rating scales to
measure each of the following could include:
A person’s feelings towards a new park being
built in their neighbourhood:
•
How likely a person is to help an older person
in need:
•
Activity 0.8
Choose either overt or covert.
2
Covert: The researcher can monitor CCTV
in the park or act like a member of the
public and observe and record behaviours in
person. They can sit on a bench or pretend
to be having a picnic but observe others
without their knowledge.
Overt: The researcher can put up a sign
letting people know littering is being
4
Please rate how likely you would be to help
an older person cross the road on a scale
of 0–5 (0 being very unlikely, 5 being
very likely)
Someone’s attitudes towards using social media:
•
1
I will use the new park regularly (strongly
agree, agree, neither agree or disagree,
disagree, strongly disagree)
Indicate how often you use social
media (every day, once a week, once a
month, never)
Activity 0.10
1
If the students answer ‘questionnaires’ this
could be justified by suggesting that they are
suitable to collect data from large groups
of people, like a whole neighbourhood. If
the student suggests ‘interviews’ they could
justify this by proposing that interviews
with some people in the community might
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CAMBRIDGE IGCSE™ PSYCHOLOGY: COURSEBOOK ANSWERS
get more in-depth or truthful opinions
than questionnaires.
2
Examples of open questions could include:
•
Explain how you feel about the
proposed playground.
•
Why do you think the town planners
have chosen this location?
Examples of closed questions could include:
•
Do you agree a new playground is
needed? (yes / no)
•
Rate your satisfaction with the size of
the proposed playground on a scale of
0–5, with 0 being not at all satisfied
and 5 being very satisfied.
Activity 0.11
1
Milner and Corkin used tests and tasks to
collect data in their case study, such as the
maze recall test.
2
Using multiple data collection techniques
will check whether or not each method
produces similar findings. This comparison
is known as triangulation and is a way of
checking whether research findings are valid.
3
People who have experienced brain damage
might be vulnerable and not capable of
giving their consent to participate. Damage
to their brain may mean they have difficulty
understanding what is happening to them
or what they are agreeing to. The person
might not understand that they can end
their participation in the study or may be
more likely to experience distress when
undertaking tasks.
Activity 0.12
The outcome will depend on the factors the
students have chosen to investigate. For example,
if they chose to investigate Judy’s routine in
getting to class (how she travels and what else
she does before class) the plan could include:
5
•
Researcher can collect data by interviewing
Judy and her parents.
•
They can ask what time she gets up, has
breakfast, what time she leaves for school
and how she gets to school each day.
Responses could include example of questions
or behavioural categories that might be used to
collect data.
Activity 0.13
Check students have written down the selected
participants’ responses accurately. They should
be able to identify any patterns or a lack of any
pattern of results, e.g. ‘most people preferred
lemon flavour’, ‘everyone in our sample eats
sweets more than once a week’.
Students should recognise that opportunity
sampling involves selecting participants who are
available, rather than inviting them to take part
or making any effort to ensure you get a mixture
of different people. In this sample, students
should recognise participants were similar in age,
or have other things in common. This means they
are unlikely to represent other groups of people,
and the results they found may not be true of
those other people.
Activity 0.14
Mr Okie can either:
•
Email his students a link to a questionnaire
about their classroom layout preferences.
The survey can contain questions or images
about the different types of layout. Those
students who respond are the voluntary
participants.
•
Put up a poster asking students willing
to take part in an observation to attend a
classroom at lunchtime on three different
days. The classroom can be set up in rows,
group tables or a U-shape. Mr Okie can
observe the volunteers for 20 mins as they
revise or complete homework to see how
they work or enjoy each layout.
Activity 0.15
Validity is important because it shows the extent
to which the research being carried out is truly
testing what the researcher aimed to test from
the outset. When research is valid, we can be sure
that any changes to the dependent variable are
due to the independent variable rather than due
to anything else.
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CAMBRIDGE IGCSE™ PSYCHOLOGY: COURSEBOOK ANSWERS
Extraneous variables in this investigation could
include: what else participants eat as part of their
diet; how much exercise the participants do; any
other lifestyle changes.
These extraneous variables could be controlled
for by telling participants not to change
anything else about their life in the second week.
Participants should keep to their usual level of
exercise; their usual diet (aside from the increase
of fruit and vegetables); and their usual lifestyle.
As the design is repeated measures and the sleep
quality of each participant is being compared
from one week to the other, the only variable that
should change in those two weeks is the amount
of fruit and vegetables they eat.
Activity 0.16
Different answers may be given. Objective ways
must be numerical, physical, or other measures
that do not rely on interpretation, for example
observation using behavioural categories.
Subjective ways must be interviews, observations
without behavioural categories, or using own
interpretation.
1
Objective way: heart rate. Subjective way:
observation without behavioural categories.
2
Objective way: time taken to run 100 metres.
Subjective way: interview.
3
Objective way: percentage of correct answers
in a maths test. Subjective way: interview.
4
Objective way: observation using
behavioural categories. Subjective way:
observation without behavioural categories.
5
Objective way: number of errors on a task.
Subjective way: opinion of quality of
participant’s performance in a task.
Activity 0.17
Each student’s presentation will be different but
it must include explanations and examples of
the key terms:
6
•
validity
•
subjectivity
•
objectivity
•
reliability
•
inter-rater reliability
•
inter-observer reliability
Notes for the presentation should be brief or
bullet-pointed and should not be full sentences
of written text.
Activity 0.18
Television is bad:
Sometimes when my mum would tell me to turn
the television off I would get angry and upset,
so maybe it was not such a good thing after all.
Some children learn bad language or learn bad
behaviours from watching television.
I do not think it is such a good idea to let
children watch too much television by themselves.
Children may be missing out on other activities
like being outside or reading.
I think if I have children I will not let them watch
very much television.
Television is good:
I think children should be allowed to watch as
much television as they want to.
I watched loads of television when I was a child
and it did not do me any harm.
I think some television can be really beneficial for
children – lots of children’s programmes teach
things like taking turns and playing well and
healthy eating so children get good things from it.
I think it is a good idea for parents to watch
television with their children so they can spend
time enjoying something together.
Watching television can be a good activity for
children because it means they can rest and have
some quiet time after a busy day at school.
I would not want my children to be the only ones
who do not watch it.
The text extracts under each heading are
completely different. They present very different
versions of the participant’s views. This shows
how subjective researchers can be and that if
they are not careful they can let their opinions
and expectations influence the way they interpret
data. Inter-rater reliability is important because
it can reduce the effect of subjectivity and make
results more consistent.
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CAMBRIDGE IGCSE™ PSYCHOLOGY: COURSEBOOK ANSWERS
Activity 0.19
In the experiment you will be asked to rate your
mood on a scale of 1–7 with 1 being very low
mood and 7 being very high mood.
1
To investigate the effect of sugar intake
on dreaming.
2
To investigate the effect of social support
on stress levels.
3
To investigate the effect of singing on mood.
The experiment should last approximately
20 minutes.
4
To investigate the effect of frustration
on aggression.
If you have any questions or concerns now,
please feel free to ask.
5
To investigate the effect of fresh air
on concentration.
Activity 0.20
Creative activity where students should produce
a poster, using creative ways to illustrate the
different types of materials used, such as:
•
stimuli (e.g. a film)
•
tests / tasks (e.g. a puzzle)
•
behavioural categories (e.g. taking a toy
from another child)
•
questions (e.g. ‘what type of sport do
you play?’).
Activity 0.21
Next you will be asked to colour for 15 minutes
and then rate your mood on a scale of 1–7 again.
Your data will be kept confidential which means
that your name will not be used and you will not
be identifiable.
You have the right to withdraw from the research
now or at any time throughout the research. You
also have the right to withdraw your data after
the research has been completed.
If you have any questions or concerns after the
research, please contact me on *****@*****.com.
Activity 0.23
1
It can be concluded that male drivers make
more errors in driving tests than female
drivers.
2
It can be concluded that nine-year-olds take
turns more times than six-year-olds and
three-year-olds, and that six-year-olds take
turns more than three-year-olds.
3
It can be concluded that memory recall is
not affected by listening to heavy metal
music, classical music or periods of silence.
Types of research that an ethical committee
would refuse include examples where:
•
participants are put under great distress
or suffer pain
•
participants are not briefed or
debriefed properly
•
data is not confidential
•
participants are not given the right
to withdraw.
Suggested amendments would include:
•
reducing distress / pain
•
giving full debrief
•
ensuring data is confidential
•
giving participants the right to withdraw.
Students’ responses will differ depending on their
research idea and what sort of research they
choose. The students’ work should include each
of the bullet points in the activity and should be
appropriate and practical.
Activity 0.25
Activity 0.22
The outcome of this activity will depend on
the data tables that students select. An example
might be:
Responses will vary, but an example is as follows:
•
The aim of this experiment is to investigate the
effect of colouring on mood.
7
Activity 0.24
The purpose of the data table is to show soft
drink preferences for men and women.
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CAMBRIDGE IGCSE™ PSYCHOLOGY: COURSEBOOK ANSWERS
•
One result from interpreting the data table is that men rated their preference for water an average of
5.5 out 10 and women rated their preference as 3 out of 10.
•
One conclusion you can reach from the bar chart is that men have a stronger preference for water
compared to women.
Activity 0.26
This is an open-ended activity. The posters designed by students should include definitions of the mean,
median and mode, with examples for each:
Mean: Score calculated by adding all the scores and then dividing by the number of scores in the set of data
Median: Score that appears in the middle of a set of data, when arranged from the smallest score to the
largest score
Mode: Score that appears most frequently in a set of data
Activity 0.27
Fusion: 13 (23–10)
Hawks: 22 (25–3)
Mean enjoyment rating (0–10)
Activity 0.28
10
9
8
7
6
5
4
3
2
1
0
Students’ enjoyment of exercise by year group
Year 7
Year 9
Year 11
Team sport
Individual
sport
Type of activity
Individual
exercise
Questions
1
8
a
Independent variable: is manipulated or observed to be present before the dependent variable;
may have two or more conditions or levels.
b
Dependent variable: is measured or observed to change after the independent variable.
c
xtraneous variable: a variable, other than the independent variable, that can have an impact on
E
the dependent variable in an experiment.
d
Control: step taken by researcher to reduce or keep the impact of extraneous variable(s) constant.
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CAMBRIDGE IGCSE™ PSYCHOLOGY: COURSEBOOK ANSWERS
2
a
b
3
a
Repeated measures: ask 25 participants
to complete condition A and then
to complete condition B. She would
ask the other 25 participants to
complete condition B and then to
complete condition A. Results between
participants in each condition would
be compared.
Independent measures: ask 25
participants to complete condition
A and 25 participants to complete
condition B. The participants would be
randomly assigned to each condition
using a random number generator.
Results between participants in each
condition would be compared.
I ndependent variable: healthy eating –
e.g., five portions of fruit and veg per
day compared to no portions of fruit
and veg per day.
Dependent variable: energy levels –
e.g., energy level rating scale.
b
Extraneous variable: could be the
amount of fat and protein in the diet.
This could be controlled by telling
participants how much fat and protein
to consume during the study.
4
In a structured observation, behavioural
categories are operationalised.
5
In a covert observation, participants are
unaware they are being watched but in
13
an overt observation participants are
fully aware.
6
Researchers choose to use unstructured
observations when they are unsure what
behaviours they might see, or use them
to get ideas to help design a structured
observation.
7
Closed question.
8
Yes / no, checklist or rating scale, or also tick
from a list of responses (any two of the
three options).
9
Describe what you enjoy about your
favourite subject.
10 A case study is an in-depth investigation
into one participant or a small group of
participants, like a family.
11 Case studies are suitable when a
phenomenon is rare like an exceptional
memory or when they want to investigate
something, it would be unethical to
manipulate through the experimental
method (e.g. when studying people with
experience of brain damage).
12 A researcher triangulates their findings
in a case study by conducting different
data collection methods, like interviewing
the subject of the case study, and their
family members, and observing them. The
researcher can compare these results to see
if their conclusions are valid.
Research scenario
Population
Sample size
A questionnaire on stress
levels in university students
People who
are studying at
university
100–150
people
Students who are full-time
Students on the same
course
An experiment on how sleep
affects children’s mood
Children aged
8–12 years
10–15
children
Children without sleep
disorders
An interview about males’ and Adult males and
5–10 adults
females’ use of social media
females in the UK
Feature(s) of the sample
Regular social media users
on one or more platforms
14 Answers may vary but exemplars for each scenario are as follows:
A questionnaire on stress levels in university students:
•
opportunity sample: approach students on campus and ask them to take part. This is an
opportunity sample as the participants are whoever is available at the time of the research.
An experiment on how sleep affects children’s mood:
•
9
volunteer sample: put a poster advertising the study up in a playground. This is a volunteer study as
potential participants would have to contact the researchers to offer to take part in the research.
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CAMBRIDGE IGCSE™ PSYCHOLOGY: COURSEBOOK ANSWERS
An interview about males’ and females’ use
of social media:
•
volunteer sample: post an advertisement
on a social media group inviting people
to apply. This is a volunteer study as
potential participants would have to
contact the researchers to offer to take
part in the research.
15 aValidity: extent to which the researcher
is investigating what they aimed
to investigate.
b
Reliability: consistency of procedure or
measures used to collect data in research.
16 Subjectivity refers to researchers using
their opinions and feelings to interpret
what they see, whereas objectivity refers to
researchers not being influenced by their
opinions and feelings. Subjective measures
include interviews and observations without
behavioural categories. Objective measures
include numerical or physical measures and
observations using behavioural categories.
17 a
b
18 a
One difference between inter-rater
reliability and inter-observer reliability
is that inter-rater reliability refers to
researchers interpreting responses
from participants such as in interviews,
whereas inter-observer reliability refers
to researchers interpreting behaviours
that they are observing.
One similarity between inter-rater
reliability and inter-observer reliability
is that they are both measuring the
extent to which there is agreement or
consistency between interpretations of
two or more researchers.
•
Consent: they must ensure the
participant fully understands the
aims of the study and what they
will be asked to do. They must
be told that participation will not
affect their release. They will also
need permission from the prison to
have access to the prisoner.
•
Confidentiality: The prisoners’ data
may be especially sensitive and so
additional care should be taken to
anonymise data and change details
to protect the participant’s identity.
10
•
Right to withdraw: the participant
should be assured that they have
the right to withdraw at any point
during the study; even though they
are confined to prison they have
the same rights within the research
as any other participant.
b
•
Privacy: The research experiment
on personal space might involve
observing people so this could be
done in public where they would
expect to be seen by others. People
might have their personal space
threatened, which breaches privacy
and so the researchers could
consider a computer simulation
or alternative research method to
protect privacy.
•
Minimising harm: researchers
should consider physical and
psychological risks to themselves
and participants. If a stooge is
used to test a participant’s personal
space, this should be done carefully
to avoid potential physical or
verbal aggression if the participant
feels threatened.
•
Debriefing: Participants should be
told the aim of the study after the
data collection is complete. If they
were observed covertly or a stooge
was used to create the personal
space experiment, participants
should be informed afterwards.
19 The researcher should consider whether
there is a safer or less unpleasant way to
conduct their experiment to prevent physical
harm. For example, the water might not
need to be so cold, or the submersion not so
long. The researcher should check whether
participants are afraid of putting their face
in water or have a health condition which
might be worsened by taking part.
In terms of psychological harm, this could
be minimised by having a less boring or
shorter task. Participants could also receive
a debriefing with a fun or interesting activity
to help them leave the study in the same
state of mind as when they entered.
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CAMBRIDGE IGCSE™ PSYCHOLOGY: COURSEBOOK ANSWERS
20 The term ‘aim’ refers to the purpose of
the research. An example of an aim is ‘to
investigate the effect of thirst on patience.’
21 Any three of: the aim; instructions; how long
the research might take; information about
what to do if the participant has queries or
concerns; right to withdraw; confidentiality
of data.
3
Case study is an in-depth investigation of a
single individual, group, or event
4
This answer may vary: flashcards should
contain the key term from the glossary for
research methods in psychology on one
side, and the definition (with or without
examples) on the other side.
5
Independent variable: rewards – children are
either given stickers for good behaviour or
not given stickers for good behaviour.
22 Results is a summary of the data collected
in research, and analysis of the data. This
can include measures of central tendency,
measures of spread; further statistical
analysis; visual representations in graphs.
Conclusions involve interpreting patterns in
the data and referring back to the aim to say
what has been learnt from the research.
23 Participant type: children / adults
24 16 children perceived a visual illusion of an
old woman and four children perceived a
young woman. The same number of adults
(10) perceived an old woman as perceived a
young woman.
Dependent variable – good behaviour – the
number of times per day a child does as they
are told immediately.
6
a
T
o investigate the effect of temperature
on concentration.
b
ula could design a task to measure
S
concentration, such as a computerised
tracking task, a puzzle to solve or a
memory test.
c
ula should consider the following
S
ethical guidelines:
25 Adults are as likely to perceive both figures in
a visual illusion. Children are more likely to
perceive a young woman in a visual illusion.
Children are more likely than adults to
perceive a young woman in a visual illusion.
Key skills
1
a
b
c
2
11
Experimental design: Way of assigning
participants to different conditions or
levels in an experiment
Repeated measures: Same participants
take part in each condition of an
experiment; participants experience all
the levels of the independent variable
Independent measures: Different
participants take part in each condition
of an experiment; participants
experience only one of the levels of the
independent variable
Objectivity can be increased through:
•
operationalising variables
•
using behavioural categories
•
using numerical or physical measures
•
using standardised procedures and
instructions.
d
•
ensuring participants agree to take
part in the research
•
protecting her participants from
harm, e.g. ensuring temperatures
are not too hot or too cold and
stress levels are not too high
•
ensuring participants are briefed
and debriefed fully (including the
aim of the study)
•
ensuring participants are made
aware they can withdraw at any
time (right to withdraw)
•
data should be kept confidential.
he aim of this experiment is to
T
investigate the effect of temperature on
concentration.
In the experiment you will be asked to
carry out a computerised tracking task
in low temperature.
Next you will be asked to carry out the
same tracking task in high temperature.
The experiment should last
approximately 30 minutes.
If you have any questions or concerns
now please feel free to ask.
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CAMBRIDGE IGCSE™ PSYCHOLOGY: COURSEBOOK ANSWERS
Your data will be kept confidential
which means that your name will not be
used and you will not be identifiable.
10 The numbers placed in order look like this:
You have the right to withdraw from the
research now or at any time throughout
the research. You also have the right to
withdraw your data after the research
has been completed.
The two central values are ‘3’ and ‘4’. Add
them together and divide by the number of
values (2) and the result is 3.5.
If you have any questions or concerns
after the research please contact me on
*****@********.com.
e
esponses will vary but an example
R
might be:
Sula might collect data such as:
Low
High
temperature temperature
Average
12
number of
errors made in
tracking task
7
aOke should consider that she may be
biased because she has expectations of
the research and holds strong opinions
about what she wants and expects to
find. She should also consider that she
and Beth may interpret what they are
observing differently, which would lead
to low inter-observer reliability.
b
8
17
Oke should try to reduce subjectivity
and increase inter-observer reliability
by using behavioural categories that
are specific and observable so neither
Oke or Beth are relying on their
own interpretation of what they are
observing.
Behaviour
Tick
Reading
Checking ticket
Looking out of window
9
12
L
uca is using covert observation. He can use
overt observation by sitting on the train and
observing people openly. He could inform
people as they enter the carriage that he will
be watching and recording behaviour.
0
2
3
3
4
5
8
11
11 A control group is important in an
experiment because this allows for a
comparison to be made to those in the
experimental group, who are exposed to the
experimental condition. A control involves
participants who are not exposed to the
experimental condition so any differences
in results between the experimental group
and control group are likely to be due to the
independent variable.
Examples will vary, but a possible response
might be:
If you are carrying out an experiment to
investigate the effect of noise on speed of
completing logic puzzles, an experimental
group could be asked to complete the
logic puzzles while loud music is playing.
Participants might take a long time or
make many errors, however, without a
control group you would not be certain the
difficulties were due to the loud noise. If
a control group completed the same logic
puzzles in silence you would then be able to
make comparisons and be more confident
that any differences found were due to the
loud condition of the experimental group.
12 It is important to have an aim so the purpose
of the research is clear. It is important to
have a conclusion because this describes
what the research has shown, and what has
been learnt from it.
13 It is important to have research that is
valid so that we can be confident that the
researcher is investigating what they aimed
to investigate in the first place. This means
that any changes to the dependent variable
are due to the independent variable rather
than due to anything else. It is important
to have research that is reliable so that it is
consistent. This means that if you repeat the
same research with the same participants
under the same conditions you should get
the same results.
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CAMBRIDGE IGCSE™ PSYCHOLOGY: COURSEBOOK ANSWERS
14 Response will vary depending on the named
study the students select. An example
would be:
Sleep restriction (Robinson et al.)
One ethical guideline that could be followed
in this research is privacy. Participants
slept in their own homes, which meant the
researchers did not invade their personal
space. The researchers also minimised harm
because the sleep restriction was only for
one night, so it was unlikely to negatively
affect the well-being of participants. The
participants gave their informed consent as
they knew that the study was about sleep
restriction and cognitive function: they were
aware of the actigraph, how long to sleep for
and that they would be doing tasks the next
day.
15 One problem with the ethics of this study
is that participants may have suffered some
temporary physical or psychological harm.
They could be very tired the next day, which
could be a risk to their safety, for example
participants might be clumsy or slow to
react. It might also affect their mood in a
negative way. For example, they might be
grumpy or easily upset.
Practice questions
1
2
3
4
13
‘Experimental conditions’ refers to the
levels of the independent variable that are
manipulated in an experiment. [1]
It is important to identify extraneous variables
because these are variables, other than the
independent variable, that could affect the
dependent variable. Once extraneous variables
are identified they can then be controlled to
minimise the effect they have. This means
that the researcher can be more certain that
any changes in the dependent variable are
due to the different levels of the independent
variable, rather than anything else. [2]
It is important to implement ethical
guidelines whilst conducting research to
make sure the participants are protected
from harm and to make sure participants
understand what the research involves and
their role in the research.
[2]
aMean: Score calculated by adding all
the scores and then dividing by the
number of scores in the set of data.
5
b
Median: Score that appears in the middle
of a set of data, when arranged from the
smallest score to the largest score.
c
Mode: Score that appears most
frequently in a set of data.
d
ange: Difference between the largest
R
score and the smallest score in a set
[4]
of data.
Answers will vary but an example is:
Circle the type of TV programme you
prefer the most:
Comedy
Drama
Sci-fi Documentary [2]
6
Answers will vary but an example is:
Researchers could collect an opportunity
sample from a target population of people
aged 18–25 by going to a university campus
and approaching students to invite them
to participate.
[2]
Chapter 1
Psychology in context
Discussion points will vary but may include
the following:
1
2
It is important for marketing teams to
use psychological research because:
•
It enables them to get a better
understanding of their potential
customers and how their minds work.
•
Marketing is an expensive tool so it
needs to be used effectively.
•
Understanding the impact of the
primacy effect, and similar concepts,
means that marketing teams can be
more successful, generate more sales
and make more profit.
The idea that television adverts shown
earlier in a set are better remembered can be
applied to web searches and advertising on
web pages in several ways:
•
The adverts that appear down the
side of a website will be subject to the
primacy effect; the adverts higher up
the list (and therefore read first) will be
more successful as they will be more
likely to be remembered.
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CAMBRIDGE IGCSE™ PSYCHOLOGY: COURSEBOOK ANSWERS
•
3
The primacy effect can be applied to
internet search results – the higher up
the list of search results a web page
is, the more likely it is to be selected.
This is partly down to the tendency to
click on the first search results you see
to save time. However, research shows
that search results at the top of the list
are more likely to be chosen because
they have been thought about and
remembered better.
3
There is also the issue of social sensitivity
as lots of personal information about him
has been shared widely, and the impact of
his illness on Wearing himself, as well as
his family, should be considered. However,
Wearing would have been given the right
to withdraw at any time, he would not have
been deceived and he has not been harmed
in any way.
The primacy effect states that earlier
information is remembered better so you
could use this in a menu design by putting
the dishes you most want to sell at the start
of each section. For example:
•
the most expensive dishes
•
a new dish that you are trying out
Activity 1.1
•
vegetable-based dishes, if you were
trying to encourage healthy eating or
encouraging vegetarian options.
1
Memory: B The way in which we process
information so that it can be stored
and retrieved.
This could be applied to all the different
sections of a menu, for example, starters,
main meals, sandwiches, desserts, and drinks.
2
Encoding: D How we process information
from the outside world so that it can enter
our memory in a usable way.
3
Storage: A How information is held in the
brain, ready to be accessed again at a
later stage.
4
Retrieval: F The way we access stored
information so that it can be used.
5
Capacity: C The amount of information that
can be held in a memory store.
6
Duration: G The length of time that
information can be held in a memory store.
7
Access: E How the information in a memory
store is reached to be used.
Psychology in real life
1
The case of Clive Wearing shows us that
short-term memory (STM) and long-term
memory (LTM) are separate. This is because
his STM was not damaged, but his LTM was
severely damaged.
It also shows that memory is very complex
– his STM still works well but the ability to
transfer memories into LTM is not working
so new memories cannot be formed.
The case study shows that the three different
types of LTM are distinct – Wearing’s
episodic memory is severely damaged,
but his procedural memory and semantic
memory are still intact.
2
A strength of a case study is that we can
learn a lot about a person. Large amounts
of both qualitative and quantitative data
can be collected so we can get a really good
understanding of that individual.
A weakness is that the research is only
carried out on one person so the study
cannot be replicated and the results cannot
be generalised to the wider population.
14
Clive Wearing would have given consent to
be investigated by psychologists. However,
although he will have consented to be
interviewed and tested, some people may
question whether he is really able to give
fully informed consent due to his
brain damage.
Activity 1.2
1
Retrograde
2
Retrograde
3
Anterograde
4
Anterograde
5
Anterograde
6
Retrograde
7
Anterograde
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CAMBRIDGE IGCSE™ PSYCHOLOGY: COURSEBOOK ANSWERS
Activity 1.3
Activity 1.6
This activity is based on students’ opinions but
could include:
Each pair’s study will vary but should follow the
procedure of Murdock’s study closely but on a
smaller scale. A smaller sample size will make
this easier to carry out, and fewer word lists can
be used.
•
•
Strengths: research support from studies such
as Craik and Tulving’s experiment 2. Useful
and a good description of how memory
works. It makes sense when applied to real life.
Student pairs could carry out the study for
just one condition then join with another pair
and combine and compare their results to get
more data.
Weaknesses: has been criticised for being
too simplistic. It cannot explain the limited
capacity of memory. It describes rather
than explains.
Activity 1.7
Activity 1.4
The MSM describes that the sensory register has
a vast capacity: so all the aspects of sights and
sounds described in the scenario will be held in
the sensory register. The information will all be
encoded in a modality-specific way so sounds will
be stored acoustically, and sights will be stored
visually. However, the duration of the sensory
register is extremely short: only up to half a
second. Any information that is not paid attention
to in that time will be lost. The reason you can
focus on what the teacher is saying and showing
you in the scenario is because those are the things
you are paying attention to so those are the bits
of information that will enter your short-term
memory for you to be aware of and process.
Students should choose one revision technique to
try out then create a mind map. Students should
be encouraged to revisit any material they struggle
to remember, and then go on to try other revision
techniques for a different section in the chapter.
Activity 1.5
15
Encoding
Capacity
Duration
Sensory
register
Modality
specific
(visual,
auditory etc)
Vast
Up to half
a second
Shortterm
memory
Acoustic
5–9 items
Around
30 seconds
Longterm
memory
Semantic
Limitless
A lifetime
Activity 1.8
This will be students’ opinions so different
answers may be given, as long as the id is
impulsive and inconsiderate of others, super-ego
is moral and polite, and ego is a sensible balance
between the other two.
Id
Ego
Super-Ego
You walk past a shop
and see an expensive
pair of shoes you love.
Buy the
expensive shoes
Look for similar but more
affordable shoes
Do not buy the shoes,
you do not need them
Someone pushes in
front of you in a queue.
Shout at them
Politely point out that
there is a queue
Do not say or do
anything, you do not
want to cause a scene
A friend forgets to meet
you for a planned lunch.
Be angry
with them
Explain that you felt upset
they forgot to meet you
and ask to rearrange
Do not say anything
so you do not
upset them
You are very hungry but
you are in a meeting
that has gone on longer
than planned.
Leave the
meeting and get
something to eat
Wait patiently and ask if it
might be possible to have
a break soon
Stay in the meeting
and sit quietly
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CAMBRIDGE IGCSE™ PSYCHOLOGY: COURSEBOOK ANSWERS
Activity 1.9
1
Suppression
2
Repression
3
Both
4
Repression
5
Suppression
6
Both
7
Both
Access: ability to get information from a
memory store.
2
Examples of declarative memories are:
holidays, first day at a new job, getting
married, having children.
3
Activity 1.10
Declarative memory includes semantic
memory (general knowledge and facts) and
episodic memory (personal events), whereas
procedural memory includes memories of
how to do things.
Students should produce a poster using colour
and creativity. The poster must include the
following terms and definitions:
Declarative memory requires conscious
recall, whereas procedural memory
is automatic.
Localisation: specific parts of the brain are
responsible for specific functions
4
Limbic system: network of brain parts involved
in processing of emotion, memory and learning
Amygdala: part of the brain involved in memory
and emotional learning
Hippocampus: part of the brain involved in
declarative memory and learning
Cerebellum: part of the brain involved in body
balance and procedural memory
Maya’s hippocampus may be damaged. This means
it is no longer able to consolidate new memories
into a long-term memory store. The ability to
transfer new memories into long-term stores is
negatively affected so new memories cannot be
stored. However, memories that had previously
been made can still be accessed because they are
not stored in the hippocampus. These memories
have already been transferred to a long-term
memory store which Maya can still access.
Questions
1
Input: incoming information that is
processed into memory
Capacity: maximum amount of information
a memory store can hold
Duration: length of time information can be
held in a memory store
Retrograde amnesia is a type of memory
loss where you are unable to remember
past memories. For example, someone
with retrograde amnesia may not be able
to remember getting married or having
children. Retrograde amnesia often results
from an injury or an illness. It can be
temporary or permanent and it has a range
of severity with some people unable to
remember any past memories, and others
able to remember some but not all
past memories.
Anterograde amnesia is a type of memory
loss where you are unable to form new
memories, but you can still recall past
memories. For example, someone with
anterograde amnesia would remember
events from years ago, such as getting
married, but would not be able to remember
a person they met or a holiday they went on
after developing the amnesia. At its most
extreme, anterograde amnesia can mean
someone is permanently unable to learn
new memories, however it is most often
temporary. Anterograde amnesia can occur
as a result of using certain prescription
drugs. It can also result from some rare
illnesses, or can be a sign of Alzheimer’s
disease (a disease that leads to memory loss
over time).
Activity 1.11
16
Examples of procedural memories are: tying
shoelaces, swimming, riding a bike, driving a
car, writing, brushing your teeth.
5
Structural, phonemic and semantic
6
Students’ responses will vary but
may include:
Structural: what colour is the word
written in?
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CAMBRIDGE IGCSE™ PSYCHOLOGY: COURSEBOOK ANSWERS
Phonemic: does it rhyme with ‘cable’?
c
Semantic: is it an item of furniture?
7
8
A description of a procedure similar to Craik
and Tulving’s experiment 2. Participants are
given lists of words and are given a question to
prompt one of the three levels of functioning.
Then participants are asked to identify the
words from a list of words. Number of
correctly recalled words is counted for each
level of processing and results are analysed.
aSensory register (SR): the store in the
Multistore model where information
from the senses is stored.
bShort-term memory (STM): the store in
the Multistore model where information
is stored temporarily until lost or
transferred into LTM.
cLong-term memory (LTM): the store in
the Multistore model where information
is stored potentially for a lifetime.
9
Information can be transferred from shortterm memory to long-term memory through
maintenance rehearsal. This is where the
information needs to be repeated.
10 The input method for STM is acoustic.
11 The duration of LTM is a lifetime.
12 The three ways of forgetting, according to
MSM are: displacement, decay and
access problems.
13 One difference between the Multistore
model (MSM) and levels of processing
(LoP) model of memory is that MSM
explains memory as an active process
whereas LoP explains it as a by-product of
processing information. Another difference
between MSM and LoP is that MSM
differentiates between short-term memory
and long-term memory whereas LoP just
explains a strong memory as a consequence
of deeper processing.
14 a
b
Freud
c
Late 1800s to early 1900s
15 a
b
17
Psychodynamic theory
C
onscious: thoughts and feelings
currently in a person’s awareness.
Pre-conscious: thoughts and feelings a
person is not currently aware of, but can
easily bring to their awareness.
Unconscious: thoughts and feelings a
person cannot bring to their awareness.
16 Positive effects of using defence
mechanisms: they can protect you from
upsetting thoughts and feelings; they can
allow you get on with your life.
Negative effects of using defence
mechanisms: they do not stop the negative
thoughts, feelings and memories from
influencing your behaviour in a negative
way; they stop you from understanding,
processing or resolving the upsetting
thoughts, feelings or memories.
17 a
mygdala: a part of the brain that
A
influences the consolidation of
memories that are emotionally-arousing
b
ippocampus: a part of the brain that
H
consolidates memories from short-term
memory (STM) to long-term memory
(LTM).
c
Cerebellum: a part of the brain involved
in body balance and procedural memory.
18 Tests showed that HM still had a normal
level of intelligence and was able to recall
childhood events but had difficulty recalling
experiences from 1–2 years before his
operation (retrograde amnesia).
HM’s ability to form new memories of
people, places and events that were new to
him since his surgery was severely impaired
(anterograde amnesia). For example, in
the night HM would ask the nurse at the
research centre how he got there.
HM was able to form some simple memories.
For example, he showed a small improvement
over time in learning to solve a simple maze.
This indicated he may be able to learn, but
much more slowly and with more errors than
people without anterograde amnesia.
19 If the cerebellum is damaged this can result
in reduced ability to learn new skills and to
perform previously learnt skills. For example,
someone with damage to their cerebellum may
no longer be able to write properly, or may
be unable to learn a new creative skill such as
knitting. Procedural memory relies on using
motor skills, coordination and predictions
about the consequences of actions. The
cerebellum is responsible for all these skills so
if it is damaged, the ability to use procedural
memory will be impaired.
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CAMBRIDGE IGCSE™ PSYCHOLOGY: COURSEBOOK ANSWERS
Key skills
1
Atkinson and Shiffrin proposed the
Multistore model (MSM) of memory in
1968. The model gets its name because it
describes memory as being made up of three
separate stores. The three stores are: sensory
register (SR), short-term memory (STM)
and long-term memory (LTM). Information
can be held in each of these stores in
different ways, in different quantities and
for different lengths of time. Information
can also be transferred between the memory
stores when required.
Sensory register is the store where
information from the senses is stored.
Information from each of the five senses
(sight, sound, smell, taste, touch) is stored
in the sensory register and is input in a
modality-specific way. This means that sight
information enters the sensory register and is
stored as sight, sound information enters the
sensory register and is stored as sound and
so on. The capacity of the sensory register is
huge – vast amounts of information can be
held here as a result of all of the stimuli your
senses are currently experiencing. However,
the duration of the sensory register is very
short – information can only be held here
for up to about half a second. This means
that most information held in the sensory
register disappears again before you have
even registered it.
However, if you pay attention to the
information in the sensory register it moves
into the STM and you become aware of
it. This means that you can now access the
information and can use it.
Information is temporarily held in STM
and can be used briefly before it is either
forgotten, or transferred into LTM. The
input of information into STM is acoustic
(as a sound). The capacity of STM is
thought to be between five and nine items.
Each item could be a letter, a number, a
word or a ‘thing’. Miller (1956) described
the capacity of STM as ‘seven plus or minus
two’, meaning that most people could hold
seven items in their STM but that some
could hold two more or two less than that
(so between five and nine). The duration of
STM is around 30 seconds.
18
To access information, it needs to be
rehearsed. This is where the information
is repeated, either to access it from STM
or to transfer it to LTM. This is called
maintenance rehearsal.
Information that has been rehearsed into
LTM has the potential to stay with you for
the rest of your life. The input of information
to LTM is semantic (according to meaning).
The capacity of LTM appears to be limitless
– it is impossible to measure completely
but research suggests that LTM can hold
all the information we could need it to. The
duration is also limitless – information held
in the LTM can last a lifetime. To access
information from LTM we need to use a
process called retrieval. This means that the
information needs to be brought back to our
STM so that we can use it.
2
Students’ responses will vary but examples
include:
procedural memory: tying shoelaces, riding
a bike, swimming.
declarative memory: a family holiday, the
first day at a new job, the continents of
the world.
3
This will take the form of a mind map but
should include the following key points:
•
Proposed by Craik and Lockhart
in 1972.
•
Memory is a by-product of
information processing.
•
LoP does not focus on different
memory stores.
•
The three levels of processing are:
•
Structural processing: the visual
features. This is shallow processing
and results in weak memories.
•
Phonemic processing: the auditory
features. This is shallow processing
and results in weak memories
(although less weak than structural
processing).
•
Semantic processing: the meaning
of the information. This is deep
processing and results in strong
memories.
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CAMBRIDGE IGCSE™ PSYCHOLOGY: COURSEBOOK ANSWERS
4
•
A summary of the named study by
Craik and Tulving.
•
LoP can explain forgetting through the
encoding specificity principle.
Conscious: thoughts and feelings currently
in a person’s awareness.
Pre-conscious: thoughts and feelings a
person is not currently aware of, but can
easily bring to their awareness.
this point. The severity of retrograde
amnesia varies so Arthur may not be able to
remember anything before his stroke or he
may only forget certain things. Retrograde
amnesia can be temporary or permanent so
Arthur may recover and he may not.
8
The researcher would expect to find
that recall of words processed at the
semantic level would be better than words
processed at the structural or phonemic
level. Furthermore, words processed at the
phonemic level would be better recalled than
words processed at the structural level.
9
As Greta is one year old, she is fully
controlled by her id as the ego and superego have not yet developed. She wants the
dolls that her sister is playing with so she
snatches them because the id is impulsive
and selfish and impatient. Liesl is five so
her ego and super-ego have developed. Her
super-ego is focused on doing the ‘right’
thing and considering others so she will let
her little sister have the doll. However, her
ego will find a way to satisfy the needs of
her id (wanting to play with a doll) but in a
way that is compromising and rational. This
means that she can let her sister have the doll
and then find another doll to play with.
Unconscious: thoughts and feelings a person
cannot bring to their awareness.
5
‘Localisation of function in the brain’
means that specific parts of the brain
are responsible for specific functions.
This means that memory, for example, is
processed by specific areas of the brain,
such as the limbic system, rather than being
shared across the whole of the brain.
6
MSM would explain these findings because
STM and LTM are separate stores. The man’s
LTM is shown to be intact as he can remember
important people, and has memories still from
throughout his life. However, his STM has
shown to be damaged as he cannot remember
information he has just been given. This means
he is unable to have a conversation, read a
book or watch television because he cannot
remember what has just happened.
7
As Arthur has had a stroke he is more
likely to suffer from retrograde amnesia as
this usually results from injury or illness.
If he does suffer from retrograde amnesia
he will have difficulties remembering past
memories. This means Arthur may not be
able to remember his family members or
any important events in his life up until
Number of words recalled
11
10 Procedural memories are formed when neural
pathways are strengthened through repetition
of an action. Whenever Carla practises
sewing, the same neural activity happens
in her brain. The more time Carla spends
practising sewing, the stronger the neural
pathway becomes. Carla can expect that
eventually the pathways will become so strong
that she will be able to sew automatically,
without having to think about it.
A bar chart showing the number of words
recalled using each level of processing
12
10
19
8
6
4
2
0
Structural
Phonemic
Semantic
Level of processing
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CAMBRIDGE IGCSE™ PSYCHOLOGY: COURSEBOOK ANSWERS
12 Students will make their own opinion but it
will be based on the following points:
•
MSM is supported by Murdock’s serial
position effect study.
•
MSM is limited because it cannot
explain depth of processing.
•
MSM considers the different stores
of memory.
•
MSM is supported by case studies of
people, such as Clive Wearing, with
brain damage to either STM or LTM
but not both.
•
LoP is supported by Craik and
Tulving’s experiment 2.
•
LoP is limited because it cannot explain
the limited capacity of memory.
•
LoP considers memory to be a byproduct of information processing.
•
LoP and MSM can both explain
forgetting in different ways.
•
LoP and MSM can both be applied
to real life.
13 Students’ responses may vary but the essay
should include the following material:
The hippocampus is a small brain structure
located in the inner temporal lobe.
The hippocampus has many important
functions, including the following roles
related to memory:
•
organising and storing new memories
•
attaching emotion to memories to
make the memories stronger
•
spatial memory and navigation
•
consolidating memories from STM
to LTM.
One of the key roles of the hippocampus
is in consolidating memories from STM to
LTM (making the memory stronger so it is
more likely to become permanent and less
likely to be forgotten).
Consolidation means making the memory
stronger so that it becomes permanent and
is less likely to be forgotten. As discussed,
for information to be remembered, it must
be transferred from STM to LTM. The role
of the hippocampus is to consolidate new
20
memories into a long-term store. Although
long-term memories are not stored in the
hippocampus, the hippocampus temporarily
stores information before transferring it
to a long-term store. It is necessary for
the memories to be consolidated so that
they are held somewhere other than
the hippocampus.
Different types of memory are consolidated
in different ways. The hippocampus is
particularly important for the consolidation
of declarative memories (semantic and
episodic). The hippocampus mostly works
by ‘replaying’ memories to reactivate the
neural circuits (brain activity) associated
with them. This strengthens the neural
circuits so the memories are stronger and
less likely to be forgotten.
Consolidation mostly happens when
you are asleep, so getting a good night’s
sleep is important. It used to be thought
that only certain stages of sleep were
needed for memory consolidation but
more recent research is mixed. It is now
generally accepted that all stages of sleep
are important for memory consolidation,
with different processes happening in
the different stages.
Evidence for the role of the hippocampus
in memory is the case study of HM by
Milner et al. (1968). The case study of
HM provides evidence for the role of
the hippocampus in consolidation of
memories from short-term memory to
long-term memory. This is because he
had his hippocampus removed, and as a
result his ability to learn new memories
was severely impaired. This shows that the
role of the hippocampus is to consolidate
new memories into a long-term store,
as HM was no longer able to do this.
HM’s recall of memories from earlier in
his life was unaffected, which shows that
long-term memories are not stored in
the hippocampus; the hippocampus just
transfers short-term memories to a longterm store. This supports the role of the
brain in memory because it shows that the
hippocampus’ role is consolidation of shortterm memory into long-term memory.
Evidence against the role of the
hippocampus is that other parts of the brain
are also implicated in memory. Different
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CAMBRIDGE IGCSE™ PSYCHOLOGY: COURSEBOOK ANSWERS
parts of the cortex have been implicated in
different aspects of memory. The cortex is
the outer layer of the brain, and is wrinkled
in appearance, giving it a greater surface
area so more information can be processed
by nerve cells. The cortex is involved in many
higher order functions such as memory,
thinking, learning and emotions.
thorough explanation of all aspects of
memory, which limits how useful the
[4]
model is.
3
A strength of the MSM is that it has research
support. Murdock’s serial position effect
study supports MSM because it shows that
STM and LTM are separate stores. [1] The
last words in the list being recalled (recency
effect) shows evidence for STM, whereas the
first words in the list being recalled (primacy
effect) shows evidence for LTM.
[1]
Practice questions
1
2
Memory refers to the way in which we
process information from the world around
us to remember it. There are several different
models of memory, including the levels of
processing and the Multistore models. For
information to be remembered it must be
inputted, stored and retrieved so that we
can use it.
[2]
aEvidence for the LoP model of memory
is the levels of processing experiment 2
by Craik and Tulving. Participants who
processed the words at a deeper level
(semantic processing) had better recall
than those who processed the words
at a shallower level (phonemic and
structural). The deeper analysis of the
words during semantic processing meant
that a stronger memory could be made
so the words were easier to recall. The
more basic processing at the structural
level meant that a strong memory was
not formed so the words were difficult
to recall. Phonemic processing led to
slightly better recall than structural
processing because the processing was
at a slightly deeper level, though still
considered to be shallow processing.
This study supports the LoP model of
memory because it shows that deeper
processing leads to stronger memories.[4]
b
21
Evidence against the model is that it
cannot explain the limited capacity
of memory. The LoP model explains
memory as being just a by-product of
information processing and does not
explain why we can only remember
a certain amount of information
at any time. This is in contrast to
the Multistore model, which clearly
explains the capacity of memory and
why it is limited. This is a weakness
of the LoP model of memory as it
means that it does not give us a full and
There are strengths and weaknesses to
the MSM, suggesting that it can explain
memory accurately to some extent but
not fully.
However, a weakness of the MSM is that it
is too simplistic and cannot explain depth
of processing. [1] The MSM describes
the process of rehearsal (repeating the
information over and over) as a way of
transferring information from STM to
LTM to remember it. However, the levels of
processing experiment 2 by Craik and Tulving
emphasises the importance of the different
levels of processing in determining how well
information is remembered. This therefore
suggests that MSM can only explain memory
to some extent but not fully.
[1]
4
The psychodynamic theory was developed
by psychologist Sigmund Freud in the late
1800s to early 1900s. The theory was built
on by other psychologists who agreed with
his views. [1] The basic assumption of the
psychodynamic theory is that behaviour
can best be explained by looking at the
unconscious. [1] Psychodynamic theory
states that all behaviour has a cause, even if
the reason is not clear. The psychodynamic
theory proposes that forgetting takes place if
a memory is unpleasant or upsetting. Humans
are motivated to forget something if it is
painful or difficult to think about, as a way
of removing the pain or upset. Sometimes
this motivated forgetting can be conscious
or deliberate. [1] Usually, however, the
unconscious mind is responsible for forgetting
these painful memories, to remove them from
our conscious awareness. [1] This is a very
different approach to the other explanations
of forgetting discussed in this chapter. In
previous examples, forgetting occurs as a
result of illness, injury or a limitation of the
[4]
memory’s capacity or duration.
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Original material © Cambridge University Press & Assessment 2025. This material is not final and is subject to further changes prior to publication.