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PSYC213 (SUMMER) : Lecture 1

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Lecture 1: Introduction and what is cognition?
- Research Ethics
- What is Cognition?
- Some History
- Key approaches to cognition (a.k.a. How we read the mind)
RESEARCH ETHICS
- Issues of ethics early in psychology
- When you are experimenting with humans, you need to make sure you respect human rights.
- In early psychology, certain experiments did not address the human rights and ethical considerations: Little
Albert and the Milgram Experiment
Little Albert (conducted by Watson)
- Albert is a baby.
- Albert shows little fear at first. He is unafraid of flames and is unafraid of a white rat.
- Then, Watson presents the rat with a clapping sound (clapping sound in the presence of the rat).
- Albert gets scared of the clapping sound. As the experiment is done over and over again, Albert becomes
scared of all furry animals because he associates them with the clapping sound.
- This is what Watson calls behaviorism. Behaviorism states that fears are learned.
What makes this experiment unethical?
- It is unethical to induce fear in someone without his or her consent. In this case the subject is a child and the
parents need to provide asset (consent), but it is not clear whether consent was provided.
- Watson never unconditioned the fear of furry animals. Thus, there are negative consequences that last way
after the experiment is over.
Milgram experiment (conducted by Milgram)
- Experiment on the obedience to authority figures.
- Subjects were recruited and were randomized into a “teacher” or a “student” group. All teachers were
volunteers. Students were actors.
- The teachers had to ask questions to the students who were in another separate room. They had to administer
an electrical shock when the student gave a wrong answer to a question.
- As the students got more questions wrong, the voltage of the electrical shock increased. The students started
screaming “ouch” and “stop” as the shocks got more “painful”.
- They teachers were “prompted” to continue the experiment with 4 prompts given by an authority figure.
Results: 2/3 of the volunteers were likely to administer a deadly shock when given instruction by an authority
figure (i.e. a man in a white coat). Americans are able to commit acts against their consciousness.
What makes the experiment unethical?
- There was deception involved. The participants did not know that the shock that they were administering was
not real.
- They underwent a lot of stress although the experiment was not real
- They were discouraged from withdrawing, which should not be the case in modern research (humans should
be able to withdraw from an experiment without any consequences).
o Milgram was trained to say 4 prompts: “Please continue”, “The experiment requires that you
continue”, “It’s absolutely essential that you continue”, “You have no other choice, you must go
on”.
o He made them feel like they actually couldn’t withdraw using these prompts although he did not
actually tie them to a chair.
RESEARCH ETHICS
Results? Measures were put in place to ensure that experiments addressed the human rights and ethical
considerations
- Belmort Report (1970)
- APA Guidelines
- University Ethics Boards: Every University has a Research Ethics
Board, where professors need to explain the points of deception,
withdraw processes, etc. oft their experiment. Only once approval by
the Ethics Board is granted can an experiment be conducted
- SCENARIO: Janice is talking to her friend Susan on the phone. In
this tiny slice of time, Janice is actually engaging in lots of cognition
processes at the same time (refer to image)
TOPICS WE WILL COVER
- Attention (people on campus, Susan talking on the phone) Chapter 4 & Guest Lecture 1
- Remembering something from the past (she told Susan he would return her book) Chapters 6 - 8
- Distinguishes items in a category (she thinks about possible options for transportation) Chapter 9
- Visualizes something (the book on her desk) Chapter 11
- Understands and produces language (she talks to Susan) Chapter10
- Works to solve a problem (she thinks about how she is going to get places without a car) Chapter 12
- Makes a decision (she decides to postpone her meetup with Susan) Chapter 12
WHAT DID YOU SAY ABOUT THE MIND?
-
“If you put your mind to it, I’m sure you’ll figure out the math problem!”
“I really haven’t made up my mind”
“He is so out of his mind!”
It’s everywhere!
 Basically, we as humans are interested in what is going on in other people’s minds and are super interested
in the mind.
WHAT IS COGNITION CONCERNED WITH?
- How do we scientifically get inside the processes that occur in the mind?
o How do we measure them objectively to understand what is happening?
- A rich, changing history of how scientists have addressed this question.
- Using scientific methods to study the mind is relatively modern!
- Previously thought to be impossible – to study the mental processes because we couldn’t actually see them
happening, they weren’t in front of us.
SOME HISTORY
ANALYTIC INTROSPECTION
- In the late 19th century, Wilhelm Wundt (the father of experimental psychology) and his student Edward
Bradford Titchener launched a new research enterprise, which was the first research laboratory to study the
mind.
- They stipulated that psychology needed to focus largely on the study of conscious mental events — feelings,
thoughts, perceptions, and recollections
- Because it was unclear to them how people were able to study other people’s thoughts, they stated that the only
person who can experience or observe your thoughts is you.
- They concluded that the only way to study thought is through analytic introspection.
- Analytic introspection is “looking within yourself” and asking questions such as “ what are you thinking”, to
observe and record the content of our own mental lives and the sequence of our own experiences.
PROBLEMS WITH INTROSPECTION
- Many thoughts are unconscious (Is this truly what the person is thinking)
- Many brain are incremental
- No way to test claims (with introspection, this testability of claims is often unattainable. For example, when
you recall something from memory, you can not use analytic introspection)
JOHN B. WATSON AND BEHAVIOURISM
John B. Watson also found some problems with introspection:
- Highly variable results (different people would introspect on the same stimulus/situation differently)
- Difficult to verify (It is difficult to figure out if what that person was thinking was actually what he was
thinking)
 This led to the Creation of Behaviorism! Behavior is the starting point of consciousness!
- Behavior as the point of attack (the observation of behavior is the focal point)
- How behavior changes in response to a stimulus (Example: In the Albert video, he wanted to see how the
child behavior will change when presented with a different object)
PROBLEMS WITH BEHAVIOURISM
- Concerned only with behavior with no reference to mind
- Our behavior is modified by how we interpret a situation (Our behavior is not set in stone)
- Our interpretation of a situation affected by memories and beliefs
Example of a situation: Two girls are walking and a cute dog comes up to them. One of the girls squeezes and
pets the dog with a lot of happiness; the other girl hides behind the tree because she is scared. Both girls
experience the same stimulus, but they have different behaviors. Using behaviorism, there is no way to know
why this behavior was different in the two girls
RE-INTRODUCING THE MIND INTO PSYCHOLOGY
- Edward Tolman: He called himself behaviorist, but he was potentially the first cognitive psychologist
(a) A rat was put in a maze and was allowed to explore.
(b) The rat quickly learned that he needs to turn right at
the curve to get food (reward of food)
(c) When the rat was placed at c, he turned at left at c.
The rat should have turned right at c if he was using
reward stimulus.
= When the rat first explored the maze, he had developed a
cognitive map.
SKINNER, CHOMSKY AND VERBAL BEHAVIOUR
- B.F. Skinner vs Noam Chomsky
- Concept of Reward as a Motivation for developing speech in children:
According to Skinner, when children were required to learn language to imitate their parents, they were rewarded.
They children would get positive feedback when they used good language; this stimulated the development of
speech. When the children used bad language, they were not rewarded and would get negative or no feedback;
the children would not learn to speak.
- A linguist called Chomsky pointed out situations in which children learned to say things that would have never
been rewarded
THE FALL OF BEHAVIOURISM
- Children could say things such as:
- “I hate you mommy!”
- “The boy hitted the ball” (grammatically incorrect)
If the children were saying things like that, the parents would have never rewarded them. However, the
children still said these type of things, indicating that reward was not a motivation for developing speech.
THE INFORMATION PROCESSING APPROACH
- The digital computer is invented
- Series of steps where information is received, stored and processed by providing outputs
Basically, computers operate at a series of stages: information is input, processed and outputted
- Could the mind work the same way too?
The information in the world is inputted and then processed in the human mind. How can we think of behavior
as a series of steps?
BRAND NEW RESEARCH QUESTIONS
- How do people pay attention to some things when so much else is going
on?
- Colin Cherry did an experiment where he played two different messages
simultaneously in the ears of subjects: one message in the left ear and the
other message in the right ear. One could listen to a single message
without many problems, and could ignore the second message played in
the other ear. This meant that when presented with two auditory inputs,
inputs could be ignored, while others were attended (given attention to).
THE FIRST FLOW DIAGRAM OF THE MIND
The kind of model that can be tested
 Basically, inputs (auditory information) is transmitted to the auditory system. There are two inputs (messages),
one attended and one unattended. These inputs are stored in the sensory store, where they undergo a selective
filer. The unattended message is completely blocked at this point. The input is processed (higher level processing)
and becomes part of the working memory.
This is a cognitive model. Cognitive psychologists create model like this so that they can be tested by experiments
to see whether or not they are explaining how to mind works.
COGNITIVE PSYCHOLOGY IS BORN
- Ulrich Neisser was the first to coin the term cognitive psychology in his book that was published in 1967.
HOW DO WE STUDY THE MIND
1) Timing
USING TIME TO INFER MENTAL PROCESSES
- Donders(1868) conducted an experiment regarding reaction time long before cognitive psychology was
discovered; he was interested in knowing how long it takes for people to make decisions and he was
interested in reaction times
- The idea here is that mental operations are fast but do take a measurable amount of time, and by
examining the response time (RT)—that is, how long someone needs to make a particular response —
we can often gain important insights into what’s going on in the mind.
- In the first part of the experiment, Donders asked participants to press a button. This is called Simple
reaction time because the participant was reacting to one stimulus.
-
In the second part of the experiment, there were 2 different lights participants had to chose between
pressing the left or right button. The light is the stimulus and the button press is the behavioral response.
This is called the choice reaction time. The choice reaction time allows to calculate not only the time
needed to perceive the light, but also the time needed to decide what button to press.
DONDERS AND MENTAL CHRONOMETRY
- Donders used the subtraction method:
 Choice time - Reaction time = Time to make a decision (between two choices)
The choice time encompasses both the time to perceive light and the time needed to make a choice. By
subtracting the reaction time (only the time required to perceive light), we are left with the time to needed
to make a choice.
- Choice reaction time= longer than simple reaction time (by 1/10th of a second)
- Addition of processing components
 In Donders experiment, behavior (button press) was used to study mental processes. The use of
behaviors to study mental processes is at the basis of cognitive psychology
- MENTAL CHRONOMETRY – How much time it takes to achieve certain mental processes
VIDEO OF TWO MMA FIGHTERS
- While the two MMA fighters were fighting, many decisions and mind processes occurred within a short
span of time. For example, one of the two fighters had to dodge a hit, he had to think of staying low, etc.
- The fighter has to have perceived the opponent’s body, launched a response to make sure it aims
correctly, predict where the opponent will be in their motion, while doing so, they also have to avoid
getting hit and launch a motion that prevents them from getting hit
- Cognitive psychology tries to break the behaviour down.
HOW WE STUDY THE MIND
1) Timing
2) Errors and Accuracy
ERRORS AND ACCURACY
- Herman Ebbinghaus was interested in forgetting and the memory.
o Wanted to know how information is lost over time.
- He conducted an experiment on himself and used nonsense syllables.
- He used nonsense syllables so he wouldn’t be influenced by the meaning a word (if the they were not
nonsense variables he could potentially associate them with other words and memorize them more
quickly)
- He tried remembering/memorizing the syllables and then repeating them. He first stated the first syllable
and then the two other syllables.
- He repeated this process until he had memorized all of the syllables.
- He noted the number of repetitions he had to do until he did not make a mistake in the whole sequence of
different syllables.
He used the saving method to analyze his data.
 Savings = ((Initial repetitions) – (relearning repetitions) /initial repetitions) X 100
-
-
Ebbinghaus repeated the same experiment with the
syllables at different times and days after the initial
experiment; he came up with this curve of accuracy based
on the number of repetitions and savings.
Memory was best when it was immediately tested. In
other words, you save less information as time passes.
Memory drops rapidly after the first 2 days of learning.
This shows that memory drops rapidly after the first 2
days of initial learning and then it levels off. Also shows that memory can be quantified and can
be used to determine the properties of human mind and memory
 In the Ebbinghaus experiment, Behavior (repeating syllables) was once again used to use test cognitive
processes (accuracy of memory)
More complex processes:
Experiment done during the lecture: We were asked to read the following words out loud
- Flat – Freight
- Flag – Fraud
- Flash – Front
- Flip – Frog
- Fruit – Fly
-
-
Phonological Bias
 Many students mispronounced the word “fruit”, because the last set of two words are inversed ( Fr –
Fl, instead of Fl-Fr). This leads to phonological bias, because the brain was used to a certain order of
language
Two language plans – sounds and words
Sometimes they get mixed up
 There are two language plans: one is based on the sound of the words and the other is based on the
meaning of the word. When the two plans get mixed up, there is error in language (like the one seen in
this case)
-
Phonological bias can also happen in tongue twisters when they are repeated very fast
Unique New York
Peggy Babcock Relatives
Toy Boat
HOW DO WE STUDY THE MIND
1) Timing
2) Errors and Accuracy
3) Neurophysiological activity using neuroimaging techniques
NEUROIMAGING TECHNIQUES
PET (POSITRON EMISION TOMOGRAPHY)
- PET scans start by introducing a tracer substance such as
glucose or oxygen 15 into the patient’s body; the molecules of
this tracer have been tagged with a low dose of radioactivity,
and the scan keeps track of this radioactivity, allowing us to
tell which tissues are using more of the glucose (the body’s
main fuel) and which ones are using less.
- PET scans measure how much glucose (the brain’s fuel) is
being used at specific locations within the brain; this provides a measurement of each location’s activity
level at a certain moment in time.
- Not used as often, because it is not healthy to induce tracers (external substance) in the body.
- In Alzheimer’s disease, there is a reduced utilization of glucose at the different regions of the brain; PET
can be used in the diagnosis of this disease.
o Have significantly less brain activity in the areas that are related to the memory systems, not
working healthily.
FMRI (FUNCTIONAL MAGNETIC IMAGING)
- The fMRI scans (magnet) measure the oxygen content in blood flowing through each region of the brain;
-
this turns out to be an accurate index of the level of neural activity in that region
This technique relies on the fact that the brain contains magnetic elements such as iron that can be
measured using magnets. We can also measure oxygen content of the blood flowing through each region
of the brain. This gives us a very accurate picture of the brain’s moment-to-moment activity.
In this way, fMRI scans offer an incredibly precise picture of the brain’s moment-by-moment activities.
On the picture, light blue areas are active when hearing speech. The purple areas are
activated when you have visual information. Yellow is the overlap between the two.
Experiment by Calvert et al.: Participants were put in this MRI machine and were
asked to read a talker’s lip from a silenced video. Researchers were able to show that
when they were doing this, the same part of the brain that is responsible for allowing us
to hear auditory stimuli (e.g. auditory cortex) was activated even though there was no
auditory information presented to them.
o Blue area = area active when you’re only hearing speech.
o Purple area = Active when you’re seeing visual lips.
o Yellow area = Active when you see speech and/or moving lips.
EEG(ELECTROENCEPHALOGRAPHY)
- Nerve cells communicate with each other via chemical signals. One neuron
sends a signal and another neuron receives, as transmission happens at the
brain
- To record the brain’s electrical signals, researchers generally use a cap that
has electrodes attached to it; the cap records the voltage changes occurring at
the scalp, which reflects activity in the brain underneath.
- In some procedures, researchers measure recurrent rhythms in the
brain’s activity, including rhythms that distinguish the stages of sleep.
In other procedures, they measure brain activity produced in response
to a single event — such as the presentation of a well-defined stimulus
- There is creation of a wave pattern; the wave pattern is distinct based
on activity and the waves can be examined to see how the brain
responds to different stimuli.
TMS (TRANSCRANIAL MAGNETIC STIMULATION)
- Transcranial magnetic stimulation uses an electrical current to switch off parts of the brain
- It is a strange feeling because it feels like one has no control over their own behavior.
- Can interfere with the ability to speak, use the fingers… etc.
- Strong magnetic pulse in specific areas of the brain temporarily disrupts the brain activity in that
area. This allows what functions are compromised when certain areas are targeted.
COMPUTATIONAL APPROACHES TO COGNITION
- Computer models try to approximate the ability of the human brain.
- Example: Think of Google Translate. Google Translate makes corrections to expressions that do not work in
a different language. Google Employees constantly work with cognitive psychologists and linguists because
they want Google translate to use the cognitive process of language similar of that of a human.
- Siri is another example of a computer system used to think like a human and converse like one.
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