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Cognitive Psychology 4500 Cognitive Psychology 4500 Spring 2010Spring 2010

Section 1: MWSection 1: MW Section 2: MFSection 2: MF

Dr. Diego Fernandez DuqueDr. Diego Fernandez Duque

Today’s take-home messageToday’s take-home message

psychology psychology seemsseems intuitive intuitive (unlike (unlike chemistry)chemistry)

but our but our intuitions are often wrongintuitions are often wrong

rather than relying only on intuition, rather than relying only on intuition, we should apply the scientific method we should apply the scientific method (like we do in chemistry)(like we do in chemistry)

Which center circle seems larger?

Visual Illusions: Sometimes we misperceive reality

Visual AttentionVisual Attention Basketball task Change Blindness

Although we Although we believebelieve that we have a complete and that we have a complete and detailed visual representation of the outside world, detailed visual representation of the outside world, studies on visual attention tell us otherwisestudies on visual attention tell us otherwise

our perception is constrained by our our perception is constrained by our knowledgeknowledge

… sometimes multiple meanings exist

(ambiguous figure)

A memory testA memory test

• Listen carefully to the list of words but don’t Listen carefully to the list of words but don’t write them downwrite them down

• When the list ends, count backward ‘by When the list ends, count backward ‘by threes’ starting at ‘42’ (39, 36, etc.)threes’ starting at ‘42’ (39, 36, etc.)

• When you get to ‘0’, write down all the When you get to ‘0’, write down all the words you recallwords you recall

sour candy sugar bitter good taste tooth nice honey soda chocolat

e

heart cake tart pie

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 theletters 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?

A F 6 7

The correct answer:

Most people select A and 6 to test the ‘if and only if’

Confirmation bias: We fail to truly test our beliefs

14

Sometimes intuition is rightSometimes intuition is right– When ‘silently’ rehearsing a phone When ‘silently’ rehearsing a phone

number, we use the brain speech areas. number, we use the brain speech areas.

but other times, it is notbut other times, it is not

In sumIn sum, psychology , psychology seemsseems intuitive intuitive (unlike (unlike chemistry)chemistry)

but intuitions are often wrongbut intuitions are often wrong– We mis-perceive (visual illusions)We mis-perceive (visual illusions)– We mis-remember (memory illusions)We mis-remember (memory illusions)– We are mis-guided (unconscious influences)We are mis-guided (unconscious influences)– We fail to check conclusions (poor We fail to check conclusions (poor

reasoning)reasoning)

we shouldn’t rely only on intuition.we shouldn’t rely only on intuition. we should apply the scientific method we should apply the scientific method

(like we do in chemistry): SYSTEMATIC (like we do in chemistry): SYSTEMATIC

How to investigate Perception & How to investigate Perception & CognitionCognition

Ask your subjects (Introspectionism)Ask your subjects (Introspectionism) First-Person Privileged AccessFirst-Person Privileged Access - before you ask, train your subjects- before you ask, train your subjects

Shortcomings of Introspectionism:Shortcomings of Introspectionism:– It provides access to It provides access to productsproducts of thinking, rather of thinking, rather

than the than the processesprocesses that underlie it. that underlie it.– It relies on It relies on conscious reportconscious report: Many interesting : Many interesting

mental events are unconscious (e.g. memory mental events are unconscious (e.g. memory retrieval, or visual processes that lead to retrieval, or visual processes that lead to perceptual perceptual illusionsillusions).).

Edward Titchener

(1867-1927)

How to investigate Perception & How to investigate Perception & CognitionCognition

Ask your subjects (Introspectionism, Ask your subjects (Introspectionism, 1900s)1900s)

Look at S-R patterns (Behaviorism, ’40s)

- Restricts psychology to truly objective, observable data

- Reaction against Instrospectionism

Behaviorism

Stimulus

Response

Study stimulus-response relations, but do NOT attempt to understand unobservable mental processes

Ivan Pavlov (1849-1936)

Classical ConditioningClassical Conditioning

Neutral stimulus becomes associated Neutral stimulus becomes associated with a stimulus that already produces a with a stimulus that already produces a responseresponse

1.1. sight of foodsight of foodsalivationsalivation

3. bell and food seen together3. bell and food seen together

4. bell4. bell salivation salivation

Behaviorism Behaviorism Psychology is the “science of behavior.” Psychology is the “science of behavior.” Emphasis on what can be Emphasis on what can be directly directly

observedobserved..– Stimuli Stimuli Responses Responses– Reinforcements / RewardsReinforcements / Rewards

Ignore the mind (unobservable).Ignore the mind (unobservable). Goal: predict behaviorGoal: predict behavior

Assets of BehaviorismAssets of Behaviorism

rigorous scientific observation rigorous scientific observation controlled laboratory settings. controlled laboratory settings. Applicable to certain areas (e.g., Applicable to certain areas (e.g.,

learning: pairing of stimuli and learning: pairing of stimuli and responses)responses)

Problems with Problems with BehaviorismBehaviorism

Limiting science to observable things is a Limiting science to observable things is a bad idea. Theories bad idea. Theories areare about unobservable about unobservable

Can’t account for much of human behavior.Can’t account for much of human behavior.– Language; AttentionLanguage; Attention

ExamplesExamples– Language (Chomsky, 1959)Language (Chomsky, 1959)

Novel words, over-generalizations, no feedbackNovel words, over-generalizations, no feedback– ‘‘mano’ (hand) -> ‘nano’ (mano’ (hand) -> ‘nano’ (meaninglessmeaningless))– ‘ ‘no mas’ (no more) -> ‘ma no’ no mas’ (no more) -> ‘ma no’

Vs. Associative Learning (Baldwin, 1992)Vs. Associative Learning (Baldwin, 1992)– Referential lookingReferential looking

– AttentionAttention Change blindnessChange blindness

– Two different stimulus -> same perceptionTwo different stimulus -> same perception– Same stimulus -> different perceptionSame stimulus -> different perception

– Spatial learning (Cognitive Maps, Tolman 1930)Spatial learning (Cognitive Maps, Tolman 1930)

What do Tolman’s Maps look like?

Edward C. Tolman (1886-1959)

learning can occur without reinforcement:learning can occur without reinforcement: Such ‘latent learning’ goes against standard behavioristic principles, which claim that learning comes only from outcomes

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

later they can deduce the shorter path.

Rats learn to follow this path …

X

Cognitive Maps in BeesCognitive Maps in Bees, , von Frisch von Frisch 19671967

behavior of bees returning to behavior of bees returning to hive after locating nectarhive after locating nectar

Can use a symbolic form of Can use a symbolic form of communicationcommunication

Different patterns of dances Different patterns of dances represent different meaningsrepresent different meanings

Round danceRound dance: source less than 100 : source less than 100 yards from hiveyards from hive

Figure 8 danceFigure 8 dance: greater distances: 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 & How to investigate Perception & CognitionCognition

Ask your subjects (Introspectionism)Ask your subjects (Introspectionism)

Look at S-R patterns (Behaviorism)Look at S-R patterns (Behaviorism)

Infer mental processes (Cognitive Infer mental processes (Cognitive Psychology)Psychology)– from S-R patterns (Reaction Time, Accuracy)from S-R patterns (Reaction Time, Accuracy)– from neural patterns (cognitive from neural patterns (cognitive

neuroscience) neuroscience)

Next ….How cognitive psychologists make inferences about what’s inside the black box...

SPARE SLIDES

It is hard to predict based on intuition It is hard to predict based on intuition

Answer: True/False; how sure you are about it?Answer: True/False; how sure you are about it?

People usually fall in love with someone very different from People usually fall in love with someone very different from themselves. In other words, opposites attract. themselves. In other words, opposites attract. T or FT or F

How sure? How sure? 5050 6060 7070 8080 9090 100100 just guessingjust guessing certaincertain

It is an optical illusion when the moon appears larger on the It is an optical illusion when the moon appears larger on the

horizon than it does overhead.horizon than it does overhead. T or F T or F

How sure? How sure? 5050 6060 7070 8080 9090 100100 just guessingjust guessing certaincertain

Hypnosis can help people accurately recall a crime scene Hypnosis can help people accurately recall a crime scene T T or For F

How sure? How sure? 5050 6060 7070 8080 9090 100100

just guessingjust guessing certaincertain

Instead of relying on intuition, we Instead of relying on intuition, we should should measure behaviormeasure behavior

For example, how long does it take to respond?For example, how long does it take to respond?

carefully measuring carefully measuring reaction time,reaction time, we can we can discover the steps of mental processing: discover the steps of mental processing: Cognitive Psychology (Cognitive Psychology (psy4500)psy4500) Cognitive Science Cognitive Science ((minorminor))

To do it well requires:To do it well requires:– A detailed analysis of the mental steps, and A detailed analysis of the mental steps, and – A comparison between two conditions that are identical A comparison between two conditions that are identical

other than in the step being investigated.other than in the step being investigated.– Preferably using stimulus and designs that are simplePreferably using stimulus and designs that are simple– A classic example: Stroop TaskA 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 activityClass activity

List the ways in which:List the ways in which:

– the two trials were well matchedthe two trials were well matched

– the trials differed from each otherthe trials differed from each other

– the experiment could be improvedthe experiment could be improved

Group activity