PY2 Core Studies: 1 - Loftus and Palmer (1974)
Study 1 - Loftus and Palmer (1974)
Reconstruction of automobile destruction: an example of the interaction
between language and memory (pg 92-97)
Field of psychology: Cognitive
1. CONTEXT AND AIMS
“I do solemnly, sincerely and truly declare and affirm that the
evidence I shall give shall be the truth, the whole truth and
nothing but the truth”
Context
The scene above is familiar to anyone who has ever watched TV. It is a cornerstone of our legal system
that without evidence, a person cannot be found guilty of a crime. This is why all witnesses must swear in
court to only tell the truth. However, what happens if the eyewitness believes that they are telling the truth,
but really they are providing testimony which is not 100% accurate? When a witness to a crime has nothing
but their own memory to rely on, can we be sure that their testimony is a real account of what actually
happened?
What is eyewitness testimony (EWT)?
Eyewitness testimony is a legal term, referring to the use of eyewitnesses to give evidence in court.

Have you ever witnessed a crime? How accurate do you think your memory
would be if you did? What factors might affect how accurate your memory is?
The Innocence project is an organisation which works to clear the names of wrongly convicted people.
They claim that eyewitness misidentification is the greatest single cause of wrongful convictions in the USA,
convictions that were later overturned by DNA evidence
One possible reason why EWT seems to be so poor is because of the role
questions.
“A leading question is a question that either by its form or content, suggests to
the witness what answer is desired, or leads him to the desired answer.
of leading
Elizabeth Loftus
These leading questions may be inadvertently be used by the police when interviewing
witnesses after the event. Information received after an event can have a retroactive
interfering effect on our recollection; in other words, retroactive interference occurs when
later learning interferes with previous learning; i.e., incoming information gets integrated and
confused with our existing knowledge.
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PY2 Core Studies: 1 - Loftus and Palmer (1974)
Previous research has suggested that the mind does not work like a camera. Our mind does not just take
a picture of what it sees, and then reproduces this memory accurately. Our memories can easily be altered
by other information.

Summarise Carmichael’s study (1932) on P95 of the text. Explain the procedure, and how it
shows that our memories can be altered by new information.
Marshall (1969) reports that when Air Force personnel, who knew in advance that they
would be asked to estimate the speed of a vehicle, actually observed a car travelling at
12 mph. their estimates ranged from 10 to 50 mph. These results suggest two things:
1: Given that there are such a range of estimates, it suggests that there might be
variables which may cause these inaccuracies such as the phrasing of a question to elicit a judgement of
speed
2:
_____________________________________________________________________________________
_____________
_____________________________________________________________________________________
_____________________________________________________________________________________
________________________________
It was Filmore (1971) who suggested that the words smashed and hit may imply
different rates of speed. These words lead the listener to assume different
consequences to the impacts to which they are referring, with hit being perceived
as gentler than smashed.
Aims
Loftus and Palmer’s experiment was actually two experiments. They wanted to investigate in general how
accurate or inaccurate memory was. Specifically they wanted to see the effect of
_____________________________________ upon estimates of _______________________. Therefore
there are two aims to this study.

Experiment 1
To see if the speed estimates given by participants upon watching a video of a
car crash would be influenced by the wording of the question asked. They
wanted to see if participants who were asked a question with the word “hit” in it
would give a different estimate of speed than those who were asked the same
question but with the word “smashed”.
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PY2 Core Studies: 1 - Loftus and Palmer (1974)

Experiment 2
Loftus and Palmer also wanted to see if the leading questions just changed the responses given to
the questions, or whether the participant’s memories had actually altered as a result of the leading
questions.
Summary
Context
 Definition of EWT
 The innocence project
 Leading questions
 Carmichael (1932)
 Marshall (1969)
 Fillmore (1971)
Aims
To see the effect of leading questions upon the
estimates of speed
 Experiment 1: leading questions and speed
estimates
 Experiment 2: alter memory or just response?
2. PROCEDURES
As stated previously, Loftus and Palmer carried out two
experiments. You need to know detailed procedures for both of
them, as well as participant numbers.

Use the information on page 93 and the text on the right (taken
from the original article), complete the summary table for
experiment 1 and 2 on the next page.
Experiment 1
Number and makeup of participants
Research method
used
Laboratory experiment
Experimental
design
Independent measures
Independent
variable
Dependant
variable
 Put the steps of the procedure of experiment 1 into the correct order.
After each film, each participant was given a
The participants were 45 students
questionnaire.
The critical question was about the speed of the
The second part of the questionnaire was a series of
cars
specific questions about the film
Each participant watched 7 films depicting a traffic
All participants were asked the question “How fast were
accident. Each film lasted from 5-30 seconds, and
the cars going when they ______ each other?”
were presented in a different order to each group.
The blank was filled with one of the following
The first item on the questionnaire was asking the
words: hit, smashed, collided, bumped or
students to simply give an account of what they had seen.
contacted
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PY2 Core Studies: 1 - Loftus and Palmer (1974)
Experiment 2
Number and makeup of participants
Research method
used
Laboratory experiment
Experimental
design
Independent measures
Independent
variable
Dependant
variable
Summarise the experiment in bullet points

Q1: Why were the participants not told about the true aims of the study?

Q2: Why were the participants given a series of questions rather than just the critical question alone?


Q3: What was the point of having a control group in the second experiment?
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PY2 Core Studies: 1 - Loftus and Palmer (1974)
3. FINDINGS AND CONCLUSIONS
Experiment 1
Findings
A Average estimate of speed for
the four videos (all participants)
Actual speed
of car crash
Mean speed
estimate
(mph)
20
37.7
30
36.2
40
39.7
40
36.1
B Average speed given for the
different verbs used
Verb used in
critical
question
Mean speed
estimate
(mph)
Smashed
40.5
Collided
39.3
Bumped
38.1
Hit
34.0
Contacted
31.8
Conclusions

What can we conclude from table A?

What can we conclude from table B?

Explain how the results above support the theory of the effect of leading questions
Loftus and Palmer give two alternate explanations of the results. It may be that the participant’s response
is biased, in other words they are uncertain whether to say 30mph or 40mph, and the verb smashed biases
their response. Alternatively, the verb used in the question may actually causes a change in the
participant’s memory such that they see the accident as being more severe than it really was.
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PY2 Core Studies: 1 - Loftus and Palmer (1974)
Experiment 2
Findings
A Average estimate of speed
for the two verbs
Verb Used in
critical
question
Mean speed
estimate
(mph)
Hit
10.46
Smashed
8.00
B No of ppts who claimed to
see broken glass
Condition
Hit
Yes
7
Smashed 16
Control
6
No
43
34
44
C – Probability of saying yes to the broken glass question for different speed estimates
Condition
1-5
Hit
.09
6-10
0.27
11-15
0.41
16-20
0.62
Smashed
.09
0.25
0.50
.06

What can we conclude from table A

What can we conclude from table B

What can we conclude from table C
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PY2 Core Studies: 1 - Loftus and Palmer (1974)
Conclusions

In experiment 1, Loftus and Palmer gave two alternate explanations of the results (biased response and
altered memory). Which explanation do the results of experiment 2 support?
Loftus and Palmer suggest that memory is made up of two types of information. What are these and how
do they combine to make a memory? There is what actually happened, what was observed, and then there
is information gained after the event. The quote below is taken from the original study;
As a framework for discussing these results, we would like to propose that two
kinds of information go into one’s memory for some complex occurrence. The first
is information gleaned during the perception of the original event; the second is
external information supplied after the fact. Over time, information from these two
sources may be integrated in such a way that we are unable to tell from which
source some specific detail is recalled. All we have is one “memory.”

Apply the above to explain the results of this experiment.
Summary
Experiment 1:
Finding: the average speed given by
participants was roughly the same across all
4 films
 Conclusion: humans are generally
bad at estimating speed
Finding: the participants gave a higher speed
estimate with the verb smashed than the
word contacted
 Conclusion: the verb used can affect
the estimate of speed, with the more
aggressive verbs being associated
with higher speeds.
Overall conclusion from experiment 1: the
verb used in a question can act as a leading
question, and lead participants to give
different estimates of speed. However, we do
not know from experiment 1 if this difference
was due to a biased response, or an altered
memory.
Experiment 2:
Finding: the average speed given for the word smashed
was higher than the average speed for the word hit
 Conclusion: like in experiment 1, the verb used has
an effect on estimates of speed
Finding: participants asked the smashed question reported
seeing more broken glass than those asked the hit
question, or those not asked about speed.
 Conclusion: the leading question has also led the
participant to remember features of the car crash
that were not there. The leading question had
altered their memory rather than just bias their
response.
Finding: the faster the participants estimated the cars were
travelling, the more likely they were to report seeing
broken glass
 Conclusion: the estimates of speed given by the
participants altered their memory, with higher
speed being associated with the presence of
broken glass.
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PY2 Core Studies: 1 - Loftus and Palmer (1974)
Overall Conclusions
Memory is made up of two types of information: what was actually perceived, and information received
after the event. Memory is therefore reconstructed from both sources of information, and therefore may be
unreliable.
4. EVALUATING THE METHODOLOGY (pg 96)

Method: The methodology used in this study was a lab experiment. What was a strength of
using this methodology is this study?
________________________________________________________________________________
_____________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________
______________________________________________________________________________

Reliability: This study has been replicated many times, and similar findings have been produced. What does
this suggest about the reliability of the study?
_____________________________________________________________________________________
_____________________________________________________________________________________
_____________________________________________________________________________________
_____________________________________________________________________________________
____________________________________
 Validity: What aspects of the study affect the ecological validity?
The setting:
_____________________________________________________________________________________
_____________________________________________________________________________________
_____________________________________________________________________________________
_____________________________________________________________________________________
_
The participants watched a video of a car crash, not a real car crash:
_____________________________________________________________________________________
_____________________________________________________________________________________
_____________________________________________________________________________________
_____________________________________________________________________________________
_____________________________________________________________________________________
The participants were aware that they were in a study: __________________________________
____________________________________________________________________________________
_____________________________________________________________________________________
_____________________________________________________________________________________
________________________
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PY2 Core Studies: 1 - Loftus and Palmer (1974)

Sampling: The sample consisted of US college students. Could there be issues with generalisability? In what
way are these participants different from the target population (all people)?
_______________________________________________________________________________
_______________________________________________________________________________
_______________________________________________________________________________
________________________________________

Ethical issues: Can you see any ethical issues with this study?
______________________________________________________________________
______________________________________________________________________
______________________________________________________________________
______________________________________________________________________
______________________________________________________________________
__________________________________________________________________________________
________
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PY2 Core Studies: 1 - Loftus and Palmer (1974)
5. CRITICALLY ASSESS WITH REFERENCE TO ALTERNATIVE EVIDENCE

Match the study to the conclusion
1: Loftus and Zanni (1975)
Showed participants a film of a car accident. Some
participants were asked “Did you see a broken headlight?”
whereas others were asked “Did you see the broken
headlight?” 7% of those asked about a broken headlight
reported seeing one, whereas 17% asked about the
headlight reported one. (There was not one in the video)
A: This research contradicts Loftus and Palmer,
as it suggests that in some circumstances,
leading questions have a limited effect on
memory. It may be that the information to be
remembered in this study was less subjective
than estimating speed.
2: Loftus (1979)
Showed participants a series of pictures of a man stealing
a red wallet from a woman’s bag. 98% of participants were
able to identify the colour correctly. Later, Loftus used
leading questions to try and alter the participants recall.
However, they persisted in describing the purse as red.
B: This study develops the research into EWT.
Whereas Loftus and Palmer investigated the
effect of leading questions in altering memories of
real events, this research suggests that leading
questions can even plan memories that were
never there. It develops the theory that verbal
information can alter memory.
3:Buckhout (1980)
A 13 second film clip of a mugging was shown on TV. An
identity parade of six suspects was later shown and
viewers asked to phone in and say who they thought had
done it.
Given that there were only six suspects, chance alone
would suggest that 17% would get it right. In fact only 14%
identified the person correctly.
4:Yullie and Cutshall (1986)
Interviewed 13 people who had witnessed an armed
robbery in Canada four months after. They included two
misleading questions. They found that the participants were
not led by the leading questions, and the accounts that they
gave were very similar to those in their initial witness
statements
5: Loftus and Pickrell (1995)
Interviewed participants about events in childhood, planting
a false memory of being lost in a mall as a child (an event
that never happened). 20% of the participants came to
believe that this event had actually happened, and some
even clung to the memory after being debriefed.
6: Braun et al (2002)
Participants who had visited Disneyland as a child were
told that they would be evaluating advertisements for it.
Group one were given an ad with no characters on it, group
two were given the same ad with a cardboard Bugs Bunny
in the corner of the room; group three were given an ad
that had bugs bunny on it, and the group four got the Bugs
Bunny ad and the cardboard Bugs Bunny. When asked
later about having met Bugs Bunny as a child, 30% of
group 2 and 40% of group 4 recalled meeting him. (Bugs
Bunny is not Disney, so this was a false memory)
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C: A criticism of Loftus and Palmer was that the
participants knew that they were in a study, and
so their behaviour may have been unnatural. This
study gets around this issue by demonstrating
that recall in real life, when participants do not
know that they will be asked to recall is still very
poor.
D: This study has the advantage of letting us see
the effect of leading questions on real life
eyewitnesses. It suggests that the results of
Loftus and Palmer only apply in a laboratory
setting, not in real life cases. It supports the
argument that Loftus and Palmer’s research lacks
ecological validity.
E: A criticism of Loftus and Palmer’s experiment
is that judging speed is complex, and therefore
the participants more prone to being led by
leading questions. This research however
demonstrates that leading questions can actually
cause participants to remember something that
was not there. This supports Loftus and Palmer,
as it provides more evidence that leading
questions can alter the response given.
F: This research build upon the results of Loftus
and Palmer, as it suggests that misinformation
does not need to be verbal for it to have an effect
on recall. False memories can be established by
non verbal/visual information.
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Use three colours to highlight research that supports, contradicts, or develops Loftus and Palmer’s
research.
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