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Cognitive Psychology 4500
Spring 2010
Section 1: MW
 Section 2: MF
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
Dr. Diego Fernandez Duque
Today’s take-home message

psychology seems intuitive

but our intuitions are often wrong

(unlike chemistry)
rather than relying only on intuition, we
should apply the scientific method (like we do
in chemistry)
Which center circle seems larger?
Visual Illusions: Sometimes we misperceive reality
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Visual
Attention
Basketball task
Change Blindness
Although we believe that we have a complete and
detailed visual representation of the outside world,
studies on visual attention tell us otherwise
our perception is constrained by our knowledge
… sometimes multiple
meanings exist
(ambiguous figure)
A memory test
•
Listen carefully to the list of words but don’t
write them down
•
When the list ends, count backward ‘by
threes’ starting at ‘42’ (39, 36, etc.)
•
When you get to ‘0’, write down all the
words you recall
 sour
 heart
 candy
 cake
 sugar
 tart
 bitter
 pie
 good
 taste
 tooth
 nice
 honey
 soda
 chocolate
Sometimes we misremember reality
Based on your gut feelings, quickly write down:
1. Your six FAVORITE letters
2. Your six LEAST FAVORITE letters
Look over each list and circle all of the letters
that occur in your own first name. Count
the number of circled letters in each list.
Which list included more of the
letters from your own first name??
Sometimes our choices are influenced by
things other than the ones we believe are
causing them
The Wason Card Selection Task
A
F
6
7
If a card has a vowel on one side, it has an even
number on the other side.
Which cards should be turned over to determined
whether this rule is being followed?
The correct answer:
A
F
6
7
Most people select A and 6 to test the ‘if and only if’
Confirmation bias: We fail to truly test our beliefs

Sometimes intuition is right
– When ‘silently’ rehearsing a phone number,
we use the brain speech areas.

but other times, it is not
14
In sum, psychology seems intuitive
(unlike
chemistry)

but intuitions are often wrong
– We
– We
– We
– We


mis-perceive (visual illusions)
mis-remember (memory illusions)
are mis-guided (unconscious influences)
fail to check conclusions (poor reasoning)
we shouldn’t rely only on intuition.
we should apply the scientific method
we do in chemistry): SYSTEMATIC
(like
How to investigate Perception & Cognition

Ask your subjects (Introspectionism)
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First-Person Privileged Access
- before you ask, train your subjects
Shortcomings of Introspectionism:
Edward
Titchener
(1867-1927)
– It provides access to products of thinking, rather than the
processes that underlie it.
– It relies on conscious report: Many interesting mental
events are unconscious (e.g. memory retrieval, or visual
processes that lead to perceptual illusions).
How to investigate Perception & Cognition

Ask your subjects (Introspectionism, 1900s)
Look at S-R patterns (Behaviorism, ’40s)
- Reaction against Instrospectionism
- Restricts psychology to truly objective, observable data
Behaviorism
Ivan Pavlov (1849-1936)
Stimulus
Study stimulus-response relations, but
do NOT attempt to understand
unobservable mental processes
Response
Classical Conditioning
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Neutral stimulus becomes associated with a
stimulus that already produces a response
1. sight of foodsalivation
3. bell and food seen together
4. bell salivation
Behaviorism
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Psychology is the “science of behavior.”
Emphasis on what can be directly observed.
– Stimuli  Responses
– Reinforcements / Rewards
Ignore the mind (unobservable).
Goal: predict behavior
Assets of Behaviorism
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rigorous scientific observation
controlled laboratory settings.
Applicable to certain areas (e.g., learning:
pairing of stimuli and responses)
Problems with Behaviorism

Limiting science to observable things is a
bad idea. Theories are about unobservable
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Can’t account for much of human behavior.
– Language; Attention
Examples
– Language (Chomsky, 1959)
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Novel words, over-generalizations, no feedback
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– ‘mano’ (hand) -> ‘nano’ (meaningless)
– ‘no mas’ (no more) -> ‘ma no’
Vs. Associative Learning (Baldwin, 1992)
– Referential looking
– Attention

Change blindness
– Two different stimulus -> same perception
– Same stimulus -> different perception
– Spatial learning (Cognitive Maps, Tolman 1930)
What do Tolman’s Maps look like?
Edward C. Tolman (1886-1959)
learning can occur without reinforcement: Such
‘latent learning’ goes against standard behavioristic
principles, which claim that learning comes only from
outcomes
Rats learn to follow this path … later they can deduce the
shorter path.
X
X
this ability cannot be explained only by links between stimuli
and responses. A better explanation is to pose the existence of
an internal spatial map
Cognitive Maps in Bees, von Frisch 1967
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behavior of bees returning to
hive after locating nectar
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Can use a symbolic form of
communication
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Different patterns of dances
represent different meanings
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Round dance: source less than 100 yards
from hive
Figure 8 dance: greater distances
Behaviorism
Stimulus
Response
Study stimulus-response relations, but do NOT attempt to
understand unobservable mental processes
Cognitive Psychology
Stimulus
Response
Study stimulus-response relations to infer the underlying
mental processes. The contents of the mind CAN be studied
scientifically
How to investigate Perception & Cognition

Ask your subjects (Introspectionism)

Look at S-R patterns (Behaviorism)

Infer mental processes (Cognitive Psychology)
– from S-R patterns (Reaction Time, Accuracy)
– from neural patterns (cognitive neuroscience)
Next ….
How cognitive psychologists make inferences
about what’s inside the black box...
SPARE SLIDES
It is hard to predict based on intuition
Answer: True/False; how sure you are about it?

People usually fall in love with someone very different from
themselves. In other words, opposites attract. T or F
How sure?
50
60
just guessing

80
90
100
certain
It is an optical illusion when the moon appears larger on the
horizon than it does overhead. T or F
How sure?
50
60
just guessing

70
70
80
90
100
certain
Hypnosis can help people accurately recall a crime scene T or F
How sure?
50
60
just guessing
70
80
90
100
certain
Instead of relying on intuition, we
should measure behavior
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For example, how long does it take to respond?
carefully measuring reaction time, we can discover the
steps of mental processing: Cognitive Psychology
(psy4500) Cognitive Science (minor)
To do it well requires:
– A detailed analysis of the mental steps, and
– A comparison between two conditions that are identical other
than in the step being investigated.
– Preferably using stimulus and designs that are simple
– A classic example: Stroop Task
GREEN
BLUE
YELLOW
RED
BLUE
YELLOW
RED
BLUE
GREEN
RED
ORANGE
BLUE
GREEN
YELLOW
ORANGE
GREEN
PURPLE
GREEN
BLACK
YELLOW
Class activity
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List the ways in which:
– the two trials were well matched
– the trials differed from each other
– the experiment could be improved