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CognitionCognition

Study of how the mind works. Study of basic Study of how the mind works. Study of basic

mental functions of the mind.mental functions of the mind.

Includes a variety of mental process: perception, Includes a variety of mental process: perception,

pattern recognition, language, etc.pattern recognition, language, etc.

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Cognition =

Organization ofKnowledge

Memory

Attention

DecisionMaking

PerceptionProblemSolving

PatternRecognition

Language

Reasoning

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Cognitive PsychologyCognitive Psychology

Theoretical orientation emphasizing mental Theoretical orientation emphasizing mental structures and processes and breaks them down structures and processes and breaks them down into component structures and processesinto component structures and processes

How sensory information is acquired, stored, How sensory information is acquired, stored, transformed and used.transformed and used.

Mental activity or acquisition, storage, Mental activity or acquisition, storage, transformation, and use of knowledgetransformation, and use of knowledge

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Neisser’s Defintion of Cognitive Neisser’s Defintion of Cognitive PsychologyPsychology

“Cognitive Psychology refers to all processes by which the sensory input is transformed, reduced elaborated, stored, recovered, and used.”

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Perception

Attention

Pattern Recognition

Memory

Organization of Knowledge

Language

Reasoning

Problem Solving

Decision Making

Levels of Cognition

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CodesCodes

System of signals used to System of signals used to representrepresent

something -- e.g. code for the alphabetsomething -- e.g. code for the alphabet

Neural Code: e.g. the word ‘hat’ encoded as Neural Code: e.g. the word ‘hat’ encoded as

a pattern of light on the retinaa pattern of light on the retina

Cognitive Code: the word ‘hat’ --> phonemes Cognitive Code: the word ‘hat’ --> phonemes

(language sounds), letters, meaning(language sounds), letters, meaning

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Level of DescriptionLevel of Description

Mental LevelMental Level

Cognitive LevelCognitive Level

Neural LevelNeural Level

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QuestionQuestion

Answer this question as quickly as you Answer this question as quickly as you can:can:

How many hands did Aristotle have?How many hands did Aristotle have?

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Cognitive Process AnalysisCognitive Process Analysis

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Cognitive Psycholgy Development TimelineCognitive Psycholgy Development Timeline

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Thinking as a Sequence of Thinking as a Sequence of StatesStates

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Wilhelm WundtWilhelm Wundt

“ “ Conscious Conscious processes and processes and immediate immediate experience”experience”

Introspection or “self Introspection or “self observation”observation”

Rigorous MethodsRigorous Methods

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TitchenerTitchener

StructuralismStructuralism

Training of observersTraining of observers

StructuralismStructuralism

Imageless thought Imageless thought

controversycontroversy

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Herman EbbinghausHerman Ebbinghaus

Study higher mental Study higher mental processes using processes using scientific methodscientific method

Process of Process of association formationassociation formation

Non-sense syllablesNon-sense syllables Savings MethodSavings Method

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Nonsense SyllablesNonsense Syllables

DAX

GIK

TEB

KOV

SUV

HET

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Ebbinghaus’ MethodEbbinghaus’ Method

1.1. Learn list to 2 perfect recitations (# trials)Learn list to 2 perfect recitations (# trials)

2.2. Set aside (varied delay)Set aside (varied delay)

3.3. Relearn (# trials)Relearn (# trials)

4.4. Measurement of SavingsMeasurement of Savings

# Trials to Learn - # Trials to Relearn

# Trials to Learn

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Measurement of SavingsMeasurement of Savings

# Trials to Learn - # Trials to Relearn

# Trials to Learn

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Forgetting CurveForgetting Curve

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William JamesWilliam James

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William James - FunctionalismWilliam James - Functionalism

Interested in the Interested in the functionsfunctions of consciousness of consciousness

Infer mental mechanisms or processes from the Infer mental mechanisms or processes from the

way organisms behave in different situations.way organisms behave in different situations.

Functions of MemoryFunctions of Memory

Primary MemoryPrimary Memory

Secondary MemorySecondary Memory

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20th Century20th Century

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BehaviorismBehaviorism

John B. Watson (1924)John B. Watson (1924)

Reaction to IntrospectionReaction to Introspection

Emphasis on observable, quantifiable Emphasis on observable, quantifiable

behaviorbehavior

No unobservables, no No unobservables, no internalinternal mental mental

states, no images, ideas, or thoughtsstates, no images, ideas, or thoughts

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BehaviorismBehaviorism

Psychology = Scientific study of behaviorPsychology = Scientific study of behavior

Humans as passive reactors to external Humans as passive reactors to external

stimulistimuli

““Tabular Rasa” - Environmental Tabular Rasa” - Environmental

determinants of behaviordeterminants of behavior

Rats in mazes, puzzle boxes, etc.Rats in mazes, puzzle boxes, etc.

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Behaviorism - Positive Behaviorism - Positive ContributionsContributions

Insistence of precise & careful definition of Insistence of precise & careful definition of

conceptsconcepts

Operational ConstructOperational Construct e.g. performance = # trials necessary to e.g. performance = # trials necessary to

complete a maze with no errorscomplete a maze with no errors

Experimental ControlExperimental Control

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Gestalt PsychologyGestalt Psychology

Laws of organizationLaws of organization

Law of proximityLaw of proximity

Law of similarityLaw of similarity

Insight problem solvingInsight problem solving

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Law of SimilarityLaw of Similarity

O O O OO O O OX X X XX X X XO O O OO O O OX X X XX X X X

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Law of ProximityLaw of Proximity

O O O O O O OOX X X X X X XXO O O O O O OOX X X X X X XX

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Frederick C. BartlettFrederick C. Bartlett

Remembering: An Experimental and Remembering: An Experimental and

Social StudySocial Study (1932) (1932)

Meaningful materials -- e.g. storiesMeaningful materials -- e.g. stories

Human memory constructive processHuman memory constructive process

Original material interpreted and Original material interpreted and

transformedtransformed

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The Cognitive RevolutionThe Cognitive Revolution

Return to mentalistic ideas (1940’s and 50’s)Return to mentalistic ideas (1940’s and 50’s)

MIT – Sept. 11, 1956MIT – Sept. 11, 1956

Neisser’s book Neisser’s book Cognitive PsychologyCognitive Psychology (1967) (1967)

Information processing perspectiveInformation processing perspective

Diverse Influences/ CausesDiverse Influences/ Causes

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Dissatisfaction with Dissatisfaction with BehaviorismBehaviorism

Challenges to “tabular rasa”Challenges to “tabular rasa”

Innate structure or knowledgeInnate structure or knowledge

Complex human behavior not explainable Complex human behavior not explainable

in terms of stimulus-response relations in terms of stimulus-response relations

alonealone

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World War IIWorld War II

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World War IIWorld War II

Practical ProblemsPractical Problems Problems of perception, judgement, Problems of perception, judgement,

thinking, and decision-makingthinking, and decision-making Operating technical equipmentOperating technical equipment Performance over LearningPerformance over Learning Human FactorsHuman Factors

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Information ProcessingInformation Processing

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Verbal LearningVerbal Learning

Flourishing of Ebbinghaus traditionFlourishing of Ebbinghaus tradition Different types of memory, memory Different types of memory, memory

organization, modelsorganization, models Active nature of learner--what is brought Active nature of learner--what is brought

to learningto learning Formation of Formation of new associationsnew associations --> Use --> Use

of of pre-existingpre-existing associations. associations. Emphasis on Memory over learningEmphasis on Memory over learning

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Bousfield (1953)Bousfield (1953)applebicycleshirtchairbananacarsocksdeskpeachtruckcouchorangetrainhatdesk

Words presented in this order:

deskcouchchairpeachapplehatshirtdress…

Etc.

But recalledIn this order

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Verbal Learning …Verbal Learning …

Existing memory associations lead to Existing memory associations lead to reorganization of words during recallreorganization of words during recall

Mental Processes: rehearsal, storage, Mental Processes: rehearsal, storage, organization, retrievalorganization, retrieval

Acceptance of objective methods & Acceptance of objective methods & proceduresprocedures

But increased commitment to But increased commitment to inferred inferred processesprocesses -- e.g. encoding, storage, -- e.g. encoding, storage, retrievalretrieval

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Noam ChomskyNoam Chomsky

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LinguisticsLinguistics

Rejection of behaviorist notions of languageRejection of behaviorist notions of language

Emphasis on mental processes underlying Emphasis on mental processes underlying

language learninglanguage learning

Novelty of utterancesNovelty of utterances

2 Major Claims2 Major Claims Language knowledge innateLanguage knowledge innate

Grammatical rules/systemGrammatical rules/system

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EvidenceEvidence

Same age of acquisitionSame age of acquisition Similar stages and length of time to Similar stages and length of time to

acquireacquire Limited # of GrammarsLimited # of Grammars Novel utterancesNovel utterances Evidence for rule use: Irregular past tense Evidence for rule use: Irregular past tense

verbsverbs

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Evidence for Rule Use: Evidence for Rule Use: Irregular past tense formationIrregular past tense formation

InitiallyInitially

‘‘go’ --> ‘went’go’ --> ‘went’

‘‘eat’ --> ‘ate’eat’ --> ‘ate’

Later (after acquiring regular past tense Later (after acquiring regular past tense

rule)rule)

‘‘go’ --> ‘goed’go’ --> ‘goed’

‘‘eat’ --> ‘eated’eat’ --> ‘eated’

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Telephone exampleTelephone example

““UD has improved the appearance of the UD has improved the appearance of the university over the last few years.”university over the last few years.”

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Communications TheoryCommunications Theory

Information processing ideaInformation processing idea

Similarity between communication devices and Similarity between communication devices and

peoplepeople

1st approximation analogy for psychology to 1st approximation analogy for psychology to

describe mental processesdescribe mental processes

Channel, information processing filters, Channel, information processing filters, limited limited

capacitycapacity, serial vs. parallel processing., serial vs. parallel processing.

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Information TheoryInformation Theory

InformationSource

Transmitter Channel Receiver Destination

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Computers & Computer Computers & Computer ScienceScience

Numerous contributionsNumerous contributions

Analogy of computers & humansAnalogy of computers & humans Both process information: Take in Both process information: Take in

information, transform, manipulate, store, & information, transform, manipulate, store, & output information (or some type of product--output information (or some type of product--e.g. behavior)e.g. behavior)

Humans & computers as symbol Humans & computers as symbol

manipulatorsmanipulators

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Schematic Diagram of Schematic Diagram of Computer SystemComputer System

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Atkinson & Shiffrin Memory ModelAtkinson & Shiffrin Memory Model

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Many Contributions Many Contributions

Borrowing of concepts & characteristics Borrowing of concepts & characteristics of computers to describe human of computers to describe human system: sensory store, short-term store, system: sensory store, short-term store, long-term storelong-term store

Limited capacity--immediate memory & Limited capacity--immediate memory & attentionattention

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Additional ContributionsAdditional Contributions

Computer programs/processes analagous to Computer programs/processes analagous to

mental processesmental processes

Simulation modelingSimulation modeling

AIAI

Computer as toolComputer as tool

ModelingModeling

Stimulus PresentationStimulus Presentation

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Current Issues Related to Current Issues Related to Cognitive PsychologyCognitive Psychology

Ecological ValidityEcological Validity

Cognitive ScienceCognitive Science

Cognitive NeuroscienceCognitive Neuroscience

Artificial IntelligenceArtificial Intelligence

Parallel Distributed Processing ApproachParallel Distributed Processing Approach

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Cognitive NeuroscienceCognitive Neuroscience

Examines how the structure & function Examines how the structure & function

of the brain explain cognitive processesof the brain explain cognitive processes

Kossylyn’s MessageKossylyn’s Message ComplexityComplexity

Necessity of cognitive/functional analysesNecessity of cognitive/functional analyses

New Tools/TechniquesNew Tools/Techniques

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Cognitive Neuroscience Cognitive Neuroscience TechniquesTechniques

Brain LessionsBrain Lessions Brain Imaging TechniquesBrain Imaging Techniques

PETPET MRIMRI fMRIfMRI

Event-related PotentialEvent-related Potential Single-cell Recording TechniqueSingle-cell Recording Technique

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PET ScanPET Scan

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Pet Scan 2Pet Scan 2

PET Scan while PET Scan while

listening to a listening to a

language task language task

(unpracticed)(unpracticed)

PET Scan after PET Scan after

practice with the task practice with the task

(spelling)(spelling)

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Event-related PotentialsEvent-related Potentials

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An ERP RecordingAn ERP Recording

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Artificial IntelligenceArtificial Intelligence

Machine MetaphorMachine Metaphor

Artificial Intelligence (Pure AI)Artificial Intelligence (Pure AI)

Computer SimulationComputer Simulation

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PDP - Parallel Distributed PDP - Parallel Distributed ProcessingProcessing

Cognitive processes can be understood in terms Cognitive processes can be understood in terms

of networks of ‘neuron-like’ unitsof networks of ‘neuron-like’ units

Connectionism vs. neural networksConnectionism vs. neural networks

Parallel vs. Serial DistinctionParallel vs. Serial Distinction

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Matlin’s 5 ThemesMatlin’s 5 Themes

Cognitive processes are activeCognitive processes are active

Cognitive processes remarkably efficient & Cognitive processes remarkably efficient &

accurateaccurate

Cognitive processes handle positive Cognitive processes handle positive

information better than negativeinformation better than negative

Cognitive processes are InterrelatedCognitive processes are Interrelated

Many cognitive processes rely on both Many cognitive processes rely on both

bottom-upbottom-up and and top-downtop-down processing processing

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What do you see?What do you see?

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Context EffectsContext Effects