11

Cognition – 2/eCognition – 2/eDr. Daniel B. WillinghamDr. Daniel B. Willingham

Chapter 1Chapter 1Cognitive Psychologists’ Cognitive Psychologists’

Approach to ResearchApproach to Research

PowerPoint by Glenn E. Meyer, Trinity UniversityPowerPoint by Glenn E. Meyer, Trinity University

©2004 Prentice Hall ©2004 Prentice Hall

22

Why Make Assumptions?Why Make Assumptions?

It is difficult to study anything without having some It is difficult to study anything without having some assumptions about the field.assumptions about the field.

There are two assumptions people make about studying the mind.There are two assumptions people make about studying the mind.1. The Starting point for study1. The Starting point for study2. Beliefs about the mind’s working (vision, attention, 2. Beliefs about the mind’s working (vision, attention, memory) memory)

If you know the assumptions – it will be clearer to If you know the assumptions – it will be clearer to you why cognitive psychologists ask the questions you why cognitive psychologists ask the questions they do.they do.

If you understand If you understand whywhy they ask the question – you they ask the question – you will better understand the answer!will better understand the answer!

©2004 Prentice Hall

33

Assumption ExamplesAssumption Examples

1.1. What Needs to Be ExplainedWhat Needs to Be Explained::Unconscious processes in vision were not Unconscious processes in vision were not considered until modern times – the considered until modern times – the assumption being that conscious processes assumption being that conscious processes are most important. are most important.

2.2. Beliefs that Influence QuestionsBeliefs that Influence Questions::If the lens in the eye inverts images, how If the lens in the eye inverts images, how come we don’t see the world upside down?come we don’t see the world upside down?

©2004 Prentice Hall

44

How Did Philosophers and Early How Did Philosophers and Early Psychologists Study the Mind?Psychologists Study the Mind?

• Philosophical UnderpinningsPhilosophical Underpinnings

• The Beginnings of Modern PsychologyThe Beginnings of Modern Psychology

• The Response: BehaviorismThe Response: Behaviorism

• Behaviorism’s SuccessBehaviorism’s Success

©2004 Prentice Hall

55

Philosophical UnderpinningsPhilosophical Underpinnings

• Ancient Greece:Ancient Greece:

• 1. Focus on the study of Perception, 1. Focus on the study of Perception, Memory and the Nature/Nurture Issue Memory and the Nature/Nurture Issue

• 2. Three Assumptions & Questions Raised:2. Three Assumptions & Questions Raised:

a. World can be understood & predicted a. World can be understood & predicted b. Human are part of the physical world b. Human are part of the physical world c. Explanations of the world should rely c. Explanations of the world should rely on events in the world and not the on events in the world and not the supernatural or mystical. supernatural or mystical.

©2004 Prentice Hall

66

Philosophical Underpinnings - Philosophical Underpinnings - ContinuedContinued

• Dark Ages and Middle AgesDark Ages and Middle Ages

• 1. Few Contributions to the Philosophy of 1. Few Contributions to the Philosophy of MindMind• 2. Causes:2. Causes:

a. Rome didn’t value knowledge for it’s a. Rome didn’t value knowledge for it’s own sake own sakeb. Barbarian invasions, Feudalism, b. Barbarian invasions, Feudalism, Decline of cities Decline of citiesc. Ascendance of Churchc. Ascendance of Church

©2004 Prentice Hall

77

Philosophical Underpinnings - Philosophical Underpinnings - ContinuedContinued

• Renaissance through the 19Renaissance through the 19thth Century Century

• 1. Return of the assumptions of the Greeks1. Return of the assumptions of the Greeksthat the world can be understood, predictedthat the world can be understood, predictedand that this was worthwhile.and that this was worthwhile.

• 2. Birth of Modern Science and Scientific Method2. Birth of Modern Science and Scientific Method•

a. World can be understood & predicteda. World can be understood & predicted b. Human are part of the physical world b. Human are part of the physical world c. Explanations of the world should rely c. Explanations of the world should rely on events in the world and not the on events in the world and not the supernatural or mystical. supernatural or mystical. d. The importance of observations d. The importance of observations

©2004 Prentice Hall

88

Philosophical Underpinnings - ContinuedPhilosophical Underpinnings - Continued

Why didn’t Psychology Started Until 1879?Why didn’t Psychology Started Until 1879?•Humans viewed as nondeterministic

•Humans viewed as having free will

•This made studying the mind seem futile

•Kant: mental processes could not be measured

•Empiricists – Hobbes, Locke, BerkeleyThe view that most of human knowledge is acquired over one’s lifetime through experience .

•Nativists - Descartes The view that much of human knowledge is innate

•Kant - Experience is the teacher but how you experience depends on native categories

On the Origin of KnowledgeOn the Origin of Knowledge

©2004 Prentice Hall

99

Philosophical Underpinnings - ContinuedPhilosophical Underpinnings - Continued

PerceptionPerception• Viewed as Part of the Nativist/Empiricist Debate

• Berkeley – even seemingly natural processes like depth perception need experience

•Empiricists – Were Also AssociationistsThe view that most of human knowledge is acquired over one’s lifetime through experience .

•Nativists - Descartes The view that much of human knowledge is innate

•Kant - Experience is the teacher but how you experience depends on native categories

MemoryMemory

©2004 Prentice Hall

1010

The Beginnings of Modern PsychologyThe Beginnings of Modern Psychology

Founding FathersFounding Fathers::

• Wilhem Wundt – 1879 – credit for first research Wilhem Wundt – 1879 – credit for first research lab dedicated to Psychologylab dedicated to Psychology

• Earlier work by James, Fechner, Weber Earlier work by James, Fechner, Weber

• However, Wundt really gave Psychology the However, Wundt really gave Psychology the official look and feel of a science: textbooks, official look and feel of a science: textbooks, symposia, journals, university department, etc.symposia, journals, university department, etc.

©2004 Prentice Hall

1111

The Beginnings of Modern Psychology The Beginnings of Modern Psychology - Continued- Continued

First SchoolsFirst Schools

• Structuralism (Wundt) :Structuralism (Wundt) :a. Metaphor was the periodic table of chemistrya. Metaphor was the periodic table of chemistryb. Goal was the describe the structuresb. Goal was the describe the structures of thoughtof thought

• Functionalism (James) :Functionalism (James) :Emphasis on function of mental processesEmphasis on function of mental processesas compared to structuresas compared to structures

• Both Schools used Introspection:Both Schools used Introspection:

Wundt’s Introspectionism:The method entails observing one’sthought processes, but it was deemed important that a more experienced introspectionist train a novice in the method

James : Less dogmatic in his approach.©2004 Prentice Hall

1212

The Response: BehaviorismThe Response: Behaviorism

• Introspectionism was unsuccessful!Introspectionism was unsuccessful!

• Watson – starts a new direction in psychologyWatson – starts a new direction in psychology

Behaviorism (1913)Behaviorism (1913)““Psychology as the behaviorist views it is a purely Psychology as the behaviorist views it is a purely objective experimental branch of natural science. objective experimental branch of natural science. Its theoretical goal is the prediction and control of Its theoretical goal is the prediction and control of behavior. Introspection forms no essential part of behavior. Introspection forms no essential part of its methods, nor is the scientific value of its data its methods, nor is the scientific value of its data dependent upon the readiness with which they dependent upon the readiness with which they lend themselves to interpretation in terms of lend themselves to interpretation in terms of consciousness.” – from consciousness.” – from Psychology as the Psychology as the Behaviorist Views it.Behaviorist Views it.

©2004 Prentice Hall

1313

The Response Continued: The Response Continued: Four Principles of BehaviorismFour Principles of Behaviorism

1.1. Psychologists should focus only on that which is Psychologists should focus only on that which is available.available.

2.2. Psychologists should explain behavior, not Psychologists should explain behavior, not thought or consciousness.thought or consciousness.

3.3. Theories should be as simple as possible.Theories should be as simple as possible.

4.4. The overarching goal of psychology is to break The overarching goal of psychology is to break down behavior into irreducible constructs – the down behavior into irreducible constructs – the building blocks of behavior. Watson’s candidate building blocks of behavior. Watson’s candidate was the conditioned reflex. was the conditioned reflex.

©2004 Prentice Hall

1414

Behaviorism’s SuccessesBehaviorism’s Successes

• Offered the idea of the Offered the idea of the reflexreflex as a basic unit of as a basic unit of behaviorbehavior

• Pavlov’s Study of Classical Conditioning:Pavlov’s Study of Classical Conditioning:Unconditioned Stimulus, Unconditioned Response, Unconditioned Stimulus, Unconditioned Response, Conditioned Stimulus, Conditioned Response – the Classic Conditioned Stimulus, Conditioned Response – the Classic Dog Salivation ParadigmDog Salivation Paradigm

• Operant Conditioning:Operant Conditioning:Learning whereby the animal (or person) makes a Learning whereby the animal (or person) makes a response that has consequences (e.g., reward or response that has consequences (e.g., reward or punishment). These consequences change the probability punishment). These consequences change the probability that the response will be made again.that the response will be made again.

©2004 Prentice Hall

1515

How Do Cognitive Psychologists How Do Cognitive Psychologists Study the Mind?Study the Mind?

• What Behaviorism Couldn’t DoWhat Behaviorism Couldn’t Do• Failures of Behaviorism to Account for Failures of Behaviorism to Account for

Human BehaviorHuman Behavior• The Computer Metaphor and Information The Computer Metaphor and Information

ProcessingProcessing• The Behaviorist ResponseThe Behaviorist Response• Abstract Constructs in Other FieldsAbstract Constructs in Other Fields• So What, Finally, Is the Cognitive So What, Finally, Is the Cognitive

Perspective?Perspective?©2004 Prentice Hall

1616

What Behaviorism Couldn’t Do.What Behaviorism Couldn’t Do.• Lacked utility in WWII human factor applications Lacked utility in WWII human factor applications

• Couldn’t deal with ethological principles (Lorenz):Couldn’t deal with ethological principles (Lorenz):

• a. Fixed action patternsa. Fixed action patterns

Complex behaviors in which an animal engages despite very limited Complex behaviors in which an animal engages despite very limited opportunities for practice or reward. Usually taken as evidence for opportunities for practice or reward. Usually taken as evidence for innate or inborn learning.innate or inborn learning.

• b. Critical periodsb. Critical periods

A window of opportunity during which a particular type of learning will A window of opportunity during which a particular type of learning will be easy for the organism. If the critical period is missed, however, the be easy for the organism. If the critical period is missed, however, the learning will be difficult or even impossible.learning will be difficult or even impossible.

©2004 Prentice Hall

1717

Failures of Behaviorism to Account for Failures of Behaviorism to Account for Human BehaviorHuman Behavior

• Problem with human behaviors such as Language :Problem with human behaviors such as Language :

Chomsky’s Criticisms of Skinner’s Chomsky’s Criticisms of Skinner’s Verbal BehaviorVerbal Behavior

a. Whitehead’s problem of the ‘Scorpion on the Table’a. Whitehead’s problem of the ‘Scorpion on the Table’b. Generative nature of languageb. Generative nature of language

• Didn’t Explain Memory Phenomena such as Bousfield (1953) Didn’t Explain Memory Phenomena such as Bousfield (1953) demonstration of retrieval strategies.demonstration of retrieval strategies.

Example - Try to recall ten minutes from now: Example - Try to recall ten minutes from now:

Lion, onion, Bill, firefighter, carrot, zebra, John, clerk, Tim, Lion, onion, Bill, firefighter, carrot, zebra, John, clerk, Tim, nurse, cow.nurse, cow.

©2004 Prentice Hall

1818

The Computer Metaphor and The Computer Metaphor and Information ProcessingInformation Processing

• Importance of Metaphor in Psychological TheoriesImportance of Metaphor in Psychological Theories

Descartes – Nervous System to Hydraulics Descartes – Nervous System to Hydraulics

1919thth Century – Brain to a Telephone Switch Board Century – Brain to a Telephone Switch Board

Hebb (1949) – Neural function to solenoids and capacitorsHebb (1949) – Neural function to solenoids and capacitors

• 1950’s – Computer Metaphor for the Mind1950’s – Computer Metaphor for the Mind1. Artificial Intelligence and computer usage of symbols 1. Artificial Intelligence and computer usage of symbols

applied to psychology modelsapplied to psychology models

2. Computer use of 2. Computer use of representationrepresentation of symbols and of symbols and processesprocesses to tomanipulate them give insight into study of the mindmanipulate them give insight into study of the mind

3. Hardware/software division in computers applied to brain/3. Hardware/software division in computers applied to brain/mindmind

©2004 Prentice Hall

1919

The Computer Metaphor - ContinuedThe Computer Metaphor - Continued•The Information Processing Model:The Information Processing Model:

Three Assumptions of Information Processing:

1. Humans are processors of information like computers and information processing supports thought and behavior

2. Representation and processes that operate on these representation underlie information processing

3. Information processing occurs within largely isolate modules which are organized into stages of processing

An approach to studying the human mind. It assumes that humans are An approach to studying the human mind. It assumes that humans are processors of information, and that representations and processing processors of information, and that representations and processing operating on them underlie cognition. Assumes also that information is operating on them underlie cognition. Assumes also that information is processed in stages.processed in stages.

©2004 Prentice Hall

2020

The Behaviorist ResponseThe Behaviorist Response• Information Processing Models relay on Information Processing Models relay on abstract constructsabstract constructs

( theoretical sets of processes and representations that you ( theoretical sets of processes and representations that you think are useful in explaining some datathink are useful in explaining some data).).For example – short term memoryFor example – short term memory

• Behaviorists have three objections to abstract constructsBehaviorists have three objections to abstract constructs

1. Constructs can be circular

2. They divert attention from behavior – which is the true subject matter of psychology, not thought

3. They are impossible to verify as they are not observable

©2004 Prentice Hall

2121

Abstract Constructs in Other FieldsAbstract Constructs in Other Fields

• Abstract Concepts are used freely and with Abstract Concepts are used freely and with rigor in other fieldsrigor in other fields

• Artificial Intelligence – Artificial Intelligence – Newell and Simon (1956) program to prove Newell and Simon (1956) program to prove formal logic theoremsformal logic theorems

• Neuroscience –Neuroscience –Tying brain structure to behavioral problemsTying brain structure to behavioral problems

Ex. – Patient H.M. and the abstract Ex. – Patient H.M. and the abstract concept concept of Short Term Memoryof Short Term Memory

©2004 Prentice Hall

2222

So What, Finally, Is the Cognitive So What, Finally, Is the Cognitive Perspective?Perspective?

• Behaviorism could account for all human Behaviorism could account for all human abilities, especially language and memoryabilities, especially language and memory

• Abstract constructs could help in Abstract constructs could help in understandingunderstanding

• Neuroscience and A.I. successfully use Neuroscience and A.I. successfully use abstract constructsabstract constructs

• The interactions of representations and The interactions of representations and processes can be compared to a computerprocesses can be compared to a computer

©2004 Prentice Hall

2323

Cognitive Perspective - ContinuedCognitive Perspective - Continued

• Chief AssumptionsChief Assumptions

1.There are representations and processes that operate on them

2.We can discover them

©2004 Prentice Hall