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Cognitive Psychology Cognitive Psychology History of Cognitive History of Cognitive Psychology Psychology

Cognitive Psychology History of Cognitive Psychology

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Cognitive PsychologyCognitive Psychology

History of Cognitive PsychologyHistory of Cognitive Psychology

History of Cognitive PsychologyHistory of Cognitive Psychology

Historical rootsHistorical roots Every epoch of human culture has wrestled with questions about human Every epoch of human culture has wrestled with questions about human

thoughtthought Cognitive psych can be seen as specifically stemming from two Cognitive psych can be seen as specifically stemming from two

different approaches to the study of human naturedifferent approaches to the study of human nature PhilosophyPhilosophy

Plato, Aristotle, Hobbes, Locke, Kant but also elsewhere around the worldPlato, Aristotle, Hobbes, Locke, Kant but also elsewhere around the world PhysiologyPhysiology

Hippocrates, HelmholtzHippocrates, Helmholtz Its background within psychology goes back to the foundation of Its background within psychology goes back to the foundation of

psychology itselfpsychology itself Wundt, James, later Gestalt psych Wundt, James, later Gestalt psych

As such, the history of cognitive psychology is much the history of As such, the history of cognitive psychology is much the history of psychology itselfpsychology itself

Historical rootsHistorical roots

The logical progression of ideasThe logical progression of ideas Hegelian dialecticHegelian dialectic

ThesisThesis AntithesisAntithesis SynthesisSynthesis

Current beliefs are challenged by Current beliefs are challenged by alternatives, leading to new theories that alternatives, leading to new theories that stem from the oldstem from the old

Historical RootsHistorical Roots

PlatoPlato Reality in abstract forms, physical world composed of imperfect Reality in abstract forms, physical world composed of imperfect

copiescopies Rationalist approach to understandingRationalist approach to understanding

Using logic to understand the worldUsing logic to understand the world AristotleAristotle

Knowledge can be obtained through experience and observationKnowledge can be obtained through experience and observation Set the stage early on for a physiological psychologySet the stage early on for a physiological psychology

HippocratesHippocrates Let’s open it up and see inside!Let’s open it up and see inside! Disease not the result of divine musingsDisease not the result of divine musings

Historical rootsHistorical roots

Key concepts arising early on:Key concepts arising early on: The mind-body connectionThe mind-body connection

Monism vs. DualismMonism vs. Dualism Innate vs. Acquired abilitiesInnate vs. Acquired abilities

Rationalism vs. empiricismRationalism vs. empiricism

Historical rootsHistorical roots

After a strong start the study of human behavior After a strong start the study of human behavior and thought did not progress muchand thought did not progress much

Up through the middle ages it could be said Up through the middle ages it could be said most were much more interested in the afterlife most were much more interested in the afterlife than life itselfthan life itself

Basis for understanding were the scriptural Basis for understanding were the scriptural accounts of phenomenaaccounts of phenomena Arguments had to support what was already accepted Arguments had to support what was already accepted

in terms of faith, contradictions to established ideas in terms of faith, contradictions to established ideas were unacceptablewere unacceptable

Historical rootsHistorical roots

The RenaissanceThe Renaissance Renewed interest in humankind (specifically Renewed interest in humankind (specifically

its abilities, not in the sense of helping our its abilities, not in the sense of helping our fellow man) and the here and nowfellow man) and the here and now

Birth of scienceBirth of science Observation and measurement key in Observation and measurement key in

understanding ourselvesunderstanding ourselves

Historical rootsHistorical roots

Beginnings of the modern periodBeginnings of the modern period DescartesDescartes

Poster child for dualismPoster child for dualism Mind and body are separate but do interact Mind and body are separate but do interact

(pineal gland)(pineal gland) LockeLocke

Mind as a Tabula rasa on which experience Mind as a Tabula rasa on which experience writeswrites

Historical rootsHistorical roots

James MillJames Mill AssociationismAssociationism ReductionismReductionism

Laws of physical universe explain what we seeLaws of physical universe explain what we see Complex ideas can be seen as associations of much simpler onesComplex ideas can be seen as associations of much simpler ones

KantKant Synthesis of empiricist and rationalist approachesSynthesis of empiricist and rationalist approaches Some knowledge is innate and independent of experience while Some knowledge is innate and independent of experience while

other knowledge requires itother knowledge requires it Understanding may be had from a synthesis of the twoUnderstanding may be had from a synthesis of the two

Modern FoundationsModern Foundations

Important aspects of 19th century psychologyImportant aspects of 19th century psychology Beginnings of scientific investigationBeginnings of scientific investigation

Fechner’s Fechner’s Elemente der PsychophysikElemente der Psychophysik 1860 1860 Focus on mental processesFocus on mental processes

Structure, function, purpose (adaptive value)Structure, function, purpose (adaptive value) HelmholtzHelmholtz

Considered to be one of the greatest scientists of the 19Considered to be one of the greatest scientists of the 19 thth century because of his century because of his contributions to the fields of physics, physiology, and eventually psychologycontributions to the fields of physics, physiology, and eventually psychology

Among many of his contributions was that he showed that measuring the speed Among many of his contributions was that he showed that measuring the speed of nerve conduction was possibleof nerve conduction was possible

Previously thought that the nonmaterial agent moved instantaneouslyPreviously thought that the nonmaterial agent moved instantaneously Paved the way for the emergence of experimental psychologyPaved the way for the emergence of experimental psychology

Thus it is only in the last 150 years was it believed that human cognition Thus it is only in the last 150 years was it believed that human cognition could even be studied, though the research could have begun much sooner, could even be studied, though the research could have begun much sooner, even hundreds of years earliereven hundreds of years earlier

E.g. simple recall studies under various conditionsE.g. simple recall studies under various conditions

Wundt and the founding of scientific Wundt and the founding of scientific psychologypsychology

Late 1800s Wundt establishes first experimental Late 1800s Wundt establishes first experimental psychology labpsychology lab

Introspection as main tool of psychology early onIntrospection as main tool of psychology early on In many cases highly trained observers reported the In many cases highly trained observers reported the

contents of their own consciousness contents of their own consciousness Focus primarily on elements of sensation and feelingFocus primarily on elements of sensation and feeling The immediate experienceThe immediate experience, , study human study human

consciousness as it occursconsciousness as it occurs Not simply breaking aspects of experience down into Not simply breaking aspects of experience down into

its constituent parts, but rather a study of its constituent parts, but rather a study of processesprocesses and the dynamical nature of cognition*and the dynamical nature of cognition*

Full circle? Dynamical Cognitive ScienceFull circle? Dynamical Cognitive Science

*Wundt was not a structuralist in the sense his student Titchener was. Cognition was more than the *Wundt was not a structuralist in the sense his student Titchener was. Cognition was more than the sum of its parts.sum of its parts.

Wundt and the founding of scientific Wundt and the founding of scientific psychologypsychology

His experimental introspection was not the His experimental introspection was not the unstructured self-observation used by unstructured self-observation used by earlier (and some later) earlier (and some later) philosophers/“psychologists”philosophers/“psychologists” Pure introspection Pure introspection

Wundt’s introspection used laboratory Wundt’s introspection used laboratory instruments to present stimuli, in most instruments to present stimuli, in most instances the subject was to respond with a instances the subject was to respond with a simple response such as saying “yes” or simple response such as saying “yes” or “no”, pressing a key“no”, pressing a key Experimental introspectionExperimental introspection

Wundt and the founding of scientific Wundt and the founding of scientific psychologypsychology

Some of Wundt’s studentsSome of Wundt’s students CattellCattell TitchenerTitchener WitmerWitmer MunsterbergMunsterberg SpearmanSpearman HallHall

Modern FoundationsModern Foundations

James’ pragmatism and the beginnings of James’ pragmatism and the beginnings of functionalism (Darwin, Cattell, Galton, Hall)functionalism (Darwin, Cattell, Galton, Hall) Reaction to Wundt (or rather, Titchener’s Reaction to Wundt (or rather, Titchener’s

interpretation of him)interpretation of him) How do cognitive processes work and what How do cognitive processes work and what

might be their purpose?might be their purpose? Stress the function of mental process rather than Stress the function of mental process rather than

contents (elements)contents (elements) Concern for practicality, emphasis on the Concern for practicality, emphasis on the

individual, and evolutionary theoryindividual, and evolutionary theory

James and the stream of James and the stream of consciousnessconsciousness

““The traditional psychologist talks like one who would say a The traditional psychologist talks like one who would say a river consists of nothing but pailsful, spoonsful, quartpotsful, river consists of nothing but pailsful, spoonsful, quartpotsful, barrelsful and other molded forms of water. Even were the barrelsful and other molded forms of water. Even were the pails and pots all actually standing in the same stream, still pails and pots all actually standing in the same stream, still between them the free water would continue to flow.”between them the free water would continue to flow.”

In opposition to those searching for mental In opposition to those searching for mental elements, he believed that: elements, he believed that: Consciousness is personalConsciousness is personal, , reflected the experience reflected the experience

of the individual.of the individual. It is continuousIt is continuous It is constantly changing, therefore we can never It is constantly changing, therefore we can never

have the exact same idea twice (Heraclitus)have the exact same idea twice (Heraclitus) It also cannot be divided up for analysisIt also cannot be divided up for analysis

Finally it is selective, and most importantly functional Finally it is selective, and most importantly functional

Modern FoundationsModern Foundations

James’ approach was mostly philosophical James’ approach was mostly philosophical and incorporated ‘armchair’ introspectionand incorporated ‘armchair’ introspection

Other labs were established here and Other labs were established here and abroad and had different varieties of abroad and had different varieties of introspection such that, at the turn of the introspection such that, at the turn of the century, we had several groups reporting century, we had several groups reporting findings mostly a reflection of their method findings mostly a reflection of their method than of substancethan of substance

Modern foundationsModern foundations

Backlash to introspectionismBacklash to introspectionism Not everything is available to consciousnessNot everything is available to consciousness How can you describe the experience while still How can you describe the experience while still

engaged in it?engaged in it? Even if one could describe accurately what you are Even if one could describe accurately what you are

experiencing, how did one come to that conclusion?experiencing, how did one come to that conclusion? Enter BehaviorismEnter Behaviorism

I got your science right here! (Pavlov, Watson, I got your science right here! (Pavlov, Watson, Skinner)Skinner)

Cut the fluff! Stick to the observables!Cut the fluff! Stick to the observables!

BehaviorismBehaviorism

The shift in American psychology from the essentially The shift in American psychology from the essentially German emphasis on the study of the processes and German emphasis on the study of the processes and elements of cognition to a primary focus on behavior was elements of cognition to a primary focus on behavior was initiated by John Watsoninitiated by John Watson ““Let us limit ourselves to things that can be observed,Let us limit ourselves to things that can be observed,

and formulate laws concerning only those things.and formulate laws concerning only those things.Now what can we observe? We can observe behaviorNow what can we observe? We can observe behavior- what the organism does or says.”- what the organism does or says.”

The immediate predecessors of behaviorism, however, The immediate predecessors of behaviorism, however, were Russian physiologists and reflexologists (Pavlov were Russian physiologists and reflexologists (Pavlov etc.)etc.)

BehaviorismBehaviorism

Classical ConditioningClassical Conditioning Conditioned reflexConditioned reflex

Operant ConditioningOperant Conditioning Pos/Neg reinforcementPos/Neg reinforcement PunishmentPunishment

Changed the perspective to that of Changed the perspective to that of prediction and control of behavior rather prediction and control of behavior rather than states of consciousnessthan states of consciousness

No reference to mental events, though No reference to mental events, though the less radical types would at least the less radical types would at least acknowledge themacknowledge them

Problems with behaviorismProblems with behaviorism Difficulty in explaining complex learningDifficulty in explaining complex learning Nomothetic application too simplistic and Nomothetic application too simplistic and

problematicproblematic Assumed that learning was the same for all Assumed that learning was the same for all

individuals (relatively the same across individuals (relatively the same across species)species)

Problems with behaviorismProblems with behaviorism

Even early on cognition was acknowledged Even early on cognition was acknowledged by some, and problems were presentby some, and problems were present

Rats that had no prior reinforcement Rats that had no prior reinforcement performed just as well as those that had performed just as well as those that had once they received it themselves (Blodgett once they received it themselves (Blodgett 1929)1929) Learning had occurred Learning had occurred in the absence of in the absence of

reinforcementreinforcement Tolman Tolman

““Cognitive maps of Rats and MenCognitive maps of Rats and Men”” Understood that cognitive process did exist Understood that cognitive process did exist

and influenced behavior – referred to them and influenced behavior – referred to them as intervening variables – variables that as intervening variables – variables that intervene between environmental events intervene between environmental events and behaviorand behavior

Problems with behaviorismProblems with behaviorism

Later on, the inefficiency of behaviorism’s Later on, the inefficiency of behaviorism’s account of language processing proved to be a account of language processing proved to be a major shortcomingmajor shortcoming

Chomsky’s critique of Skinner’s Chomsky’s critique of Skinner’s Verbal BehaviorVerbal Behavior Picture is worth 10,000 responsesPicture is worth 10,000 responses Mouses (overgeneralization of internal grammatical Mouses (overgeneralization of internal grammatical

rules) after initial correct learning, even if never heard rules) after initial correct learning, even if never heard beforebefore

Appropriate responses to novel stimuliAppropriate responses to novel stimuli Gist: language cannot be explained sufficiently Gist: language cannot be explained sufficiently

without reference to mental events.without reference to mental events.

Other perspectives: PsychoanalysisOther perspectives: Psychoanalysis

FreudFreud ExistedExisted Now he doesn’tNow he doesn’t

Moving on…Moving on…

Psychodynamic TheoryPsychodynamic Theory

Motivation, unconscious, wish-fulfillment etc.Motivation, unconscious, wish-fulfillment etc. The primary stimulus of interest is thus a hidden The primary stimulus of interest is thus a hidden

one for the most part one for the most part Contrast with behaviorists and cog psychContrast with behaviorists and cog psych

Relied more on speculation rather than Relied more on speculation rather than observation (others on the other hand must be observation (others on the other hand must be able to explain results in light of previous able to explain results in light of previous research)research)

Other perspectives: Gestalt PsychologyOther perspectives: Gestalt Psychology

Gestalt psychology was a German movement Gestalt psychology was a German movement that directly challenged ‘Wundt’s’ structural that directly challenged ‘Wundt’s’ structural psychology psychology Though again Wundt was not a structuralist in the Though again Wundt was not a structuralist in the

sense that Titchener wassense that Titchener was The goals of Gestalt psychology were to The goals of Gestalt psychology were to

investigate the organization of mental activity investigate the organization of mental activity and to determine the exact nature of the person-and to determine the exact nature of the person-environment interactionsenvironment interactions

Gestalt psychology emphasized the ‘how’ of Gestalt psychology emphasized the ‘how’ of mental processing, rather than the ‘what’mental processing, rather than the ‘what’

Gestalt PsychologyGestalt Psychology

Cognitive processes not so easily reduced Cognitive processes not so easily reduced to elementsto elements Active perceptionActive perception

Example: where is the square coming Example: where is the square coming from?from?

Gestalt PsychologyGestalt Psychology

Wertheimer, Koffka, KöhlerWertheimer, Koffka, Köhler WertheimerWertheimer

PhiPhi phenomenon (apparent movement) phenomenon (apparent movement) Illusion that a light is moving from one location to anotherIllusion that a light is moving from one location to another

Phi phenomena cannot be reduced to the stimulus elements Phi phenomena cannot be reduced to the stimulus elements presented to the subjects – the subjective experience of motion presented to the subjects – the subjective experience of motion is the result of a dynamic interaction between an observer and is the result of a dynamic interaction between an observer and the stimulithe stimuli

KöhlerKöhler Insightful chimpanzeesInsightful chimpanzees

KoffkaKoffka Perhaps most vocal and prolific proponent of gestalt principlesPerhaps most vocal and prolific proponent of gestalt principles

Gestalt PsychologyGestalt Psychology

Major aspects of perceptionMajor aspects of perception SimilaritySimilarity ProximityProximity ClosureClosure

Gestalt PsychologyGestalt Psychology

Gestalt psychology grew out of the research on sensory and Gestalt psychology grew out of the research on sensory and perceptual processes, providing also an alternative to early perceptual processes, providing also an alternative to early behaviorismbehaviorism

Seeing the salient features of shapes and forms on a background Seeing the salient features of shapes and forms on a background within a perceptual field is an innate activity and not an acquired skillwithin a perceptual field is an innate activity and not an acquired skill

Organization leading to meaning, then, is the key to our perceptual Organization leading to meaning, then, is the key to our perceptual structurestructure

‘‘Learning takes’ place as a result of psychological disequilibrium or Learning takes’ place as a result of psychological disequilibrium or tension that persists until the problem is solved – insights are swift tension that persists until the problem is solved – insights are swift and free of errorsand free of errors

The Gestalt movement played a major role in providing a contrast to The Gestalt movement played a major role in providing a contrast to behaviorism by broadening its basis to foster a more complete view behaviorism by broadening its basis to foster a more complete view of the learning process.of the learning process.

Modern FoundationsModern Foundations

But…But… How do we study it scientifically?How do we study it scientifically?

Powerful demonstrations, but not too much in the way of Powerful demonstrations, but not too much in the way of theorytheory

Also…Also… A little A little tootoo nativistic: focus on perception primarily nativistic: focus on perception primarily

based on what we bring to the tablebased on what we bring to the table Experience, expectation can affect perceptionExperience, expectation can affect perception

And…And… Who is that short guy over there with the funny Who is that short guy over there with the funny

mustache?mustache?

1950s1950s

Behaviorism had been dominating Behaviorism had been dominating American ‘psychological’ study for American ‘psychological’ study for decadesdecades

While there were pockets of ‘resistance’ While there were pockets of ‘resistance’ much of the work as far as cognition was much of the work as far as cognition was concerned was abroadconcerned was abroad

By the 1950s however, the scientific By the 1950s however, the scientific climate in psychology had changedclimate in psychology had changed

1950s1950s

(Re)Enter cognitive psychology(Re)Enter cognitive psychology From Neisser 1967From Neisser 1967

““Cognition refers to all the processes by which the Cognition refers to all the processes by which the sensory input is transformed, elaborated, stored, sensory input is transformed, elaborated, stored, recovered, and used… sensation, perception, recovered, and used… sensation, perception, imagery, retention, recall, problem-solving and imagery, retention, recall, problem-solving and thinking, among many others, refer to hypothetical thinking, among many others, refer to hypothetical stages or aspects of cognition”stages or aspects of cognition”

Cognitive Psychology is the domain of Cognitive Psychology is the domain of psychology involved in the scientific analysis of psychology involved in the scientific analysis of mental processes in order to better understand mental processes in order to better understand behaviorbehavior

Information processing approachInformation processing approach

With the advent of computing technology, a ready analogy With the advent of computing technology, a ready analogy was available to help understand how humans deal with was available to help understand how humans deal with and interact with their environmentand interact with their environment Key work ushering in the information processing approach: Key work ushering in the information processing approach: Broadbent, Perception and Communication, (1958)Broadbent, Perception and Communication, (1958) Current incarnations: Computational mind (Daniel Dennett), Current incarnations: Computational mind (Daniel Dennett),

Computational Universe (Seth Lloyd)Computational Universe (Seth Lloyd) Obviously the brain does not work like a computer, Obviously the brain does not work like a computer,

however both are involved in the processing and storage of however both are involved in the processing and storage of informationinformation

Information processing approachInformation processing approach

Neisser (1967)Neisser (1967) Provided a summary of the approach up to that timeProvided a summary of the approach up to that time Also provided a blueprint for researchAlso provided a blueprint for research

Indirect studies of cognitive processingIndirect studies of cognitive processing Example: Reaction time studiesExample: Reaction time studies

A central tenet of this approach is that A central tenet of this approach is that information is processed and stored in stagesinformation is processed and stored in stages

Atkinson & Shiffrin (1968)Atkinson & Shiffrin (1968) Short-term, Long-term memoryShort-term, Long-term memory

Craik & Lockhart (1972)Craik & Lockhart (1972) Levels of processingLevels of processing

Current information processing Current information processing modelsmodels

ConnectionismConnectionism Later models de-emphasized the serial nature of Later models de-emphasized the serial nature of

the original information processing modelthe original information processing model Information processed in parallel across regions of Information processed in parallel across regions of

the brainthe brain Flexible, able to adapt to experienceFlexible, able to adapt to experience Models were provided that simulated performance Models were provided that simulated performance

though might not have explicit physiological though might not have explicit physiological underpinningsunderpinnings

Rummelhart & McClelland (1986)Rummelhart & McClelland (1986)

Info processing takes place through the Info processing takes place through the interaction of a large number of simple interaction of a large number of simple processing elements (units) sending excitatory processing elements (units) sending excitatory and inhibitory informationand inhibitory information

Other areas: Artificial IntelligenceOther areas: Artificial Intelligence

Further development of the computer Further development of the computer brought on attempts to mimic the way the brought on attempts to mimic the way the mind thinksmind thinks Newell & Simon: The logic theoristNewell & Simon: The logic theorist Turing test (as yet, not passed)Turing test (as yet, not passed)

Information processing approachInformation processing approach

Although the information processing approach and computer Although the information processing approach and computer analogy has been extremely enlightening, it does have analogy has been extremely enlightening, it does have problemsproblems

Although computers can place chess and perform other tasks Although computers can place chess and perform other tasks similar to or even better than humans, still pale in comparison similar to or even better than humans, still pale in comparison to typical brain functioningto typical brain functioning Quantum computing?Quantum computing?

No real physiological correspondence to computer partsNo real physiological correspondence to computer parts Memory as a Memory as a functionfunction also (not just a storage device) also (not just a storage device) However the information processing perspective remains the However the information processing perspective remains the

heart of cognitive psychologyheart of cognitive psychology

Levels of explanationLevels of explanation

From Marr (1982)From Marr (1982) FunctionalFunctional

What is the goal and purpose of the processing?What is the goal and purpose of the processing? RepresentationalRepresentational

How is the information represented within the system?How is the information represented within the system? PhysicalPhysical

How is the processing physically realized?How is the processing physically realized? One can perhaps add to or rephrase (the demarcation in One can perhaps add to or rephrase (the demarcation in

actual research may blur), but the levels are particular to actual research may blur), but the levels are particular to the info-processing approachthe info-processing approach

Cognitive Psychology TodayCognitive Psychology Today

Today cognitive psychology encompasses Today cognitive psychology encompasses myriad approaches to studying a wide myriad approaches to studying a wide variety of mental processesvariety of mental processes

The term cognitive science is often used to The term cognitive science is often used to note the interdisciplinary study of cognitionnote the interdisciplinary study of cognition

Miller’s conceptualization (late 70s), though now would suggest links among all of them

Complexity is keyComplexity is key

The amazing thing about thought is that everything is too complicated for us to do Yet, we manage to get around the world.

What do we mean by complexity? There are always many possibilities Only a few of them are relevant How do we decide which ones are correct?

ComplexityComplexity

Somehow we manage to solve these problems, so what must happen? We must limit the options we consider We must think quickly enough to consider a reasonable number of options

How does this happen? The cognitive system has many ways of focusing on what is relevant Constraints promote information likely to be relevant

Some possibilities may be missed Constraints determine what is easy or hard to do

Theories suggest possible sets of constraints Experiments test whether people use those constraints.

Return to levels of explanation Theories may describe constraints at different levels of explanation

Computational level Algorithmic level Implementational level

Different kinds of data will be relevant to each type of explanation

Basic Mechanisms and Issues Basic Mechanisms and Issues

The cognitive system is the primary survival The cognitive system is the primary survival mechanism for the human species.mechanism for the human species.

And as we have been discussing we could say And as we have been discussing we could say the cognitive system works mainly on two the cognitive system works mainly on two principlesprinciples MeaningMeaning

Extract a mental model of environment (functional)Extract a mental model of environment (functional)

Cognitive Economy Cognitive Economy

Basic Mechanisms and IssuesBasic Mechanisms and Issues

AssociationAssociation Contiguity in space and timeContiguity in space and time Functional (causal) associationsFunctional (causal) associations Organization of knowledgeOrganization of knowledge

Skill/ acquisitionSkill/ acquisition LearningLearning

Power law of practicePower law of practice

Basic Mechanisms and IssuesBasic Mechanisms and Issues

Judgment/Decision makingJudgment/Decision making

Cognitive developmentCognitive development

Attention/perceptionAttention/perception How do we take info from the outside in How do we take info from the outside in

mangled form, and put it back together for mangled form, and put it back together for conscious experience and behavior?conscious experience and behavior?

Methods of InvestigationMethods of Investigation

BehavioralBehavioral NeuropsychologicalNeuropsychological Brain ImagingBrain Imaging

Event-related PotentialsEvent-related Potentials Positron Emission TomographyPositron Emission Tomography Functional Magnetic Resonance ImagingFunctional Magnetic Resonance Imaging

Methods of InvestigationMethods of Investigation

Behavioral dataBehavioral data Simple observationSimple observation Reaction time, paired-associate learning, Reaction time, paired-associate learning,

accuracy measures, free recall etc.accuracy measures, free recall etc. Indirect measure of cognition, but most Indirect measure of cognition, but most

widely usedwidely used

Methods of InvestigationMethods of Investigation

Lesion Studies Studying brain damage can tell us

something about what areas of the brain affect particular functions If an area has a lesion, and the person shows a

specific deficit, then that area probably has something to do with that function.

Example: Memory disorders Lesions of the hippocampus and memory

Methods of InvestigationMethods of Investigation

Brain ImagingBrain Imaging ERPERP

Bad spatial/Good temporal resolutionBad spatial/Good temporal resolution Look at polarity, amplitude, latency and distributionLook at polarity, amplitude, latency and distribution

Methods of InvestigationMethods of Investigation

PET and fMRIPET and fMRI Pretty picturesPretty pictures Good localizationGood localization Not as good temporal resolution, very Not as good temporal resolution, very

expensiveexpensive

fMRIfMRI Face processing (head on view)Face processing (head on view)

PET scanPET scan Normal left, Alzheimer’s rightNormal left, Alzheimer’s right

Methods of InvestigationMethods of Investigation

The FutureThe Future

Still a long way from fully understanding even Still a long way from fully understanding even some of the fundamental issuessome of the fundamental issues

As technology and knowledge advances in cog As technology and knowledge advances in cog psych and other fields (e.g. neuroscience), psych and other fields (e.g. neuroscience), further understanding will be gained about old further understanding will be gained about old issues and new problems will present issues and new problems will present themselves for further studythemselves for further study