cognitive psycology

8/12/2019 Cognitive Psycology

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History and IntroductionChapter 1

Cognitive psychology

A definition:

The scientific study of mental processes such asperceiving, remembering, using language, reasoning,and solving problems.

The formal discipline of Cognitive Psychology startedin the mid-1900s during the cognitive revolution, andthe term cognitive psychology did not emerge until1967.

Its roots can be traced back much further. Intimatelyintertwined with the history of experimental psychology.

History

Timeline showing early experiments studying the

mind in the 1800s and events associated with the

rise of behaviorism in the 1900s


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Donders (1868)

Interested in how long it takes to make a decision.

Used Reaction Time (RT) to measure decision making.

ranciscus Donders1818-1889

Simple Task Choice Task

Simple RT = stimulus perception + response !220 ms

Choice RT = stimulus perception + decision + response !320 ms

Decision= Choice RT - Simple RT !320 ms - 220 ms = 100 ms

subtractive method

From philosophy to science

Donders experiment is important because it illustratesthat mentalprocess cannot be measured directly, theymust be inferred...

from behavior.

from biological changes.

from behavioral differences associated with biologicaldifferences.

We use multiple methodologies to triangulateanswers...


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Donders

Early experimental psychology:

Structuralism

Influential figures: Wundt & Titchner

Focused on identifying the basic building blocksof conscious experience.

Tried to make a periodic table of the mind.

Main method: Analytic Introspection under controlledconditions.

Contribution to Cognitive Psychology

Emphasized systematic, controlled observation.

Importance of the understanding the structure of themind and higher cognitive processes.

Limitation

Reliance on introspection. Too Subjective.

Wilhelm Wundt

1832-1920

Edward Titchner

1867-1927

Donders

Wundt

Titchner


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Early experimental psychology

Hermann Ebbinghaus

(1850-1909)

Read lists of nonsense syllables(e.g., ZIF, DAX) aloud many timesto determine number ofrepetitions necessary to repeatlist without errors

Independent Variable

Time between tests.

Dependent Variable Savings

= [(Initial repetitions)-(Relearning repetitions)] Initial repetitions

= [(4)-(2)] = 2 = 50% 4 4

(% Savings)

Donders

Wundt

Titchner

Ebbinghaus

Early experimental psychology:Functionalists

Guiding Principles: Function of the mind, not the structure of the mind, is paramount

Introspection still ok, but should be describing behavior

Contribution to Cognitive Psychology

Helped translate the relevance of experimental psychology toother human endeavors

William James

wrote Principles of Psychology, using introspection as hisprimary method, and presaged many of the things that wevestudied for the 100+ years since

John Dewey

Best known for impact on education. Popularized student-centered, non-traditional approaches to education.

William James

1842-1910

John Dewey

1859-1952


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James

Dewey

Donders

Wundt

Titchner

Ebbinghaus

Fechner

von Helmholtz

Psychophysics

Fechner color effect:

http://www.itp.uni-hannover.de/~zawischa/ITP/benhamtop.html

https://en.wikipedia.org/wiki/Benham%27s_top

Fechners Law: a subjective sensation (S) is proportional to thelogarithm of the stimulus intensity (I)

S = K Log I

S: Psychological sensation

I: Physical intensityof the stimulus

I * 3 = S + S

I * 3 * 3 = S + S + S

Geometric increase in stimulus intensity leads to an additive increasein sensation.

Gustav Fechner

1801-1887

Influenced Ebbinghaus, Wundt, Helmholtz

The mind and body are different sides of one reality.

Attempted to discover a mathematical relationbetween mind and body (mathematical modeling).Gustav Fechner

1801-1887

Every sensation presents itself as an indivisible unit;and it is quite impossible to read any clear meaninginto the notion that they are masses of unitscombined.

criticism: stimuli may be composite, sensations arenot. William James

1842-1910


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Unconscious inference (studying vision)

Some of our perceptions are the resultof unconscious assumptionswe

make about the environment

We infer much of what we know aboutthe world

mann von Helmholtz

1821-1894

James

Dewey

Donders

Wundt

Titchner

Ebbinghaus

Fechner

Helmholtz

ThorndikePavlov

Ivan Pavlov

(1849-1936)

Edward Thorndike

(1874-1959)

Law of effect (using cats)

Puzzle box

Precursor of operant orinstrumental conditioning

Alpha, Beta Tests(ASVAB; armed forces test)

Active Learning

Classical conditioning (using dogs)

CS

UCS

UCR

CR


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Give me a dozen healthy infants, well-formed, and my own specified world to bringthem up in and Ill guarantee to take any oneat random and train him to become any typeof specialist I might select doctor, lawyer,artist, merchant-chief and, yes, evenbeggar-man and thief, regardless of histalents, penchants, tendencies, abilities,vocations, and race of his ancestors. I am

going beyond my facts and I admit it, but sohave the advocates of the contrary and theyhave been doing it for many thousands ofyears. [Behaviorism (1930), p. 82]

John Broadus Watson

1878-1958

The Decline of Behaviorism

A controversy over language acquisition

Skinner (1957)

Argued children learn language through operantconditioning

Children imitate speech they hear

Correct speech is rewarded

Opposition from Chomsky (linguist).


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The Decline of Behaviorism

Noam Chomsky (1959)

Argued children do not only learnlanguage through imitation andreinforcement, they generate.

Children say things they have neverheard and can not be imitating

Children say things that are incorrectand have not been rewarded for

Language must be determined by inbornbiological program (LAD)

Colorless green ideas sleep furiously

Syntax vs. semantics

What happens when the rats are placedin a different arm of the maze?

The rats navigated to the specific armwhere they previously found food

Supported Latent Learning, notstimulus-response learning

dward Chace Tolman

1886-1959


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Tolman (1938)

(a) Rat initially explores the maze

(b) Learns to turn right to obtain food at B when it starts at A

(c) when placed at C, the rat turns left to reach the food atB.

Limitations of Behaviorism Failures to account for aspects of human behavior

Over-emphasis on animal experimentation

Language

Skinner suggested language was learned through basicprinciples of operant conditioning (1957).

i.e., we learn to say what is rewarded

Fails to account for Generativityof language.

The creation of novel utterancesthat have never been rewarded in the past.

e.g., Chomsky (1959; linguist)

Failure to consider intervening mental

processes

Stimulus (memorize this list)

lion, onion, Bill, firefighter, carrot,zebra, John, clerk, Tom, nurse, cow

Response (recall)

lion, zebra, cow, onion, carrot,firefighter, clerk, nurse, John, Bill, Tom

Mental Processes

Strategies, grouping, reorganization, etc.

Behaviorism:

ognitive Psychology:

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The Cognitive Revolution

Throughout the 1950s there was a shift in emphasisfrom behaviorists stimulusresponse relationships to

an approach that attempts to explain behavior in termsof the mind

Overview of Different Approaches

Philosophy

Think about mental processes

Structuralism(Introspection)

Try to directly tap into mental processes

The Whatof experience

Behaviorism

Study stimulus-response relationships

Ignore mental processes

Cognitive Psychology

Study stimulus-response relationships

Make inferences about mental processes

The Howof experience

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The rebirth of the study of the mind

The digital revolution

Information Processing: inputs are transformed instages to generate outputs.

Flow diagrams for digital computers.

Flow diagrams for the mind Colin Cherry (1953): selective attention.

Broadbentsinformation processing model ofattention.

Broadbents filter model forselective attention (1958) How can you stay focused on

your conversation?

You must filter out extraneousinformation.

Hey Matt!

Attention can still be brokeninto (we will explore theseideas more in chapter 4).

Cocktail party (Cherry, 1953)

FilterDetector(semantic)

puts To memory

Studying the Mind

To understand complex cognitive behaviors:

Measure observable behavior.

Make inferencesabout underlying cognitive activity.

Consider what this behavior says about how themind works.


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Researching the Mind

Behavior approachmeasures relationship betweenstimuli and behavior.

Physiological approachmeasures relationshipbetween physiology and behavior.

Both contribute to our understanding of cognition.

Researching the Mind:Memory Consolidation

Memory for recent events is fragile.

If processing is disrupted, recent memories can fail tobe consolidated.

New information can interfere with memoryconsolidation.

Muller & Pilzecker (1900)

Two different groups learned 2 lists of items.

Immediate and delay groups.

Consolidation!

Interference!


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Gais et al. (2007)

Tested memory for word pairs in two groups: Sleep and awake

Sleep slept immediately after studying. Awake studied, stayed up for10 hours, then slept. Equally rested before testing.

Sleep group remembered more.

Injecting rats with protein synthesis inhibitors preventsthe formation of memories (Flexner et al., 1963).

The effect of sleep on memory consolidation in thehippocampus (Gais et al., 2006, 2007).

Memory consolidation:Physiology

Hippocampus

Synthesis essay

Memory impairment

Korsakoffs

Anterograde/retrograde amnesia

Neural processing

Mirror neurons

Disorders

Phantom limb syndrome

Prosopagnosia

Athletes and, e.g., memory disorders (TBI)

Memory savants

Autism

Attention

Cell phones and driving

ADHD

Language

AcquisitionDisorders (e g Brocas aphasia)

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