Transcript Cognition – 2/e Dr. . Daniel B. Willingham

Cognition – 2/e
Dr. Daniel B. Willingham
Chapter 1
Cognitive Psychologists’
Approach to Research
PowerPoint by Glenn E. Meyer, Trinity University
©2004 Prentice Hall
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Why Make Assumptions?
It is difficult to study anything without having some
assumptions about the field.
There are two assumptions people make about studying the mind.
1. The Starting point for study
2. Beliefs about the mind’s working (vision, attention,
memory)
If you know the assumptions – it will be clearer to
you why cognitive psychologists ask the questions
they do.
If you understand why they ask the question – you
will better understand the answer!
©2004 Prentice Hall
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Assumption Examples
1.
2.
What Needs to Be Explained:
Unconscious processes in vision were not
considered until modern times – the
assumption being that conscious processes
are most important.
Beliefs that Influence Questions:
If the lens in the eye inverts images, how
come we don’t see the world upside down?
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How Did Philosophers and Early
Psychologists Study the Mind?
•
Philosophical Underpinnings
•
The Beginnings of Modern Psychology
•
The Response: Behaviorism
•
Behaviorism’s Success
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Philosophical Underpinnings
•
Ancient Greece:
•
1. Focus on the study of Perception,
Memory and the Nature/Nurture Issue
•
2. Three Assumptions & Questions Raised:
a. World can be understood & predicted
b. Human are part of the physical world
c. Explanations of the world should rely
on events in the world and not the
supernatural or mystical.
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Philosophical Underpinnings Continued
•
Dark Ages and Middle Ages
•
1. Few Contributions to the Philosophy of
Mind
• 2. Causes:
a. Rome didn’t value knowledge for it’s
own sake
b. Barbarian invasions, Feudalism,
Decline of cities
c. Ascendance of Church
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Philosophical Underpinnings Continued
•
Renaissance through the 19th Century
•
1. Return of the assumptions of the Greeks
that the world can be understood, predicted
and that this was worthwhile.
•
2. Birth of Modern Science and Scientific Method
a. World can be understood & predicted
b. Human are part of the physical world
c. Explanations of the world should rely
on events in the world and not the
supernatural or mystical.
d. The importance of observations
•
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Philosophical Underpinnings - Continued
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
On the Origin of Knowledge
•Empiricists – Hobbes, Locke, Berkeley
The 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
©2004 Prentice Hall
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Philosophical Underpinnings - Continued
Perception
• Viewed as Part of the Nativist/Empiricist Debate
• Berkeley – even seemingly natural processes like depth
perception need experience
Memory
•Empiricists – Were Also Associationists
The 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
©2004 Prentice Hall
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The Beginnings of Modern Psychology
Founding Fathers:
•
Wilhem Wundt – 1879 – credit for first research
lab dedicated to Psychology
•
Earlier work by James, Fechner, Weber
•
However, Wundt really gave Psychology the
official look and feel of a science: textbooks,
symposia, journals, university department, etc.
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The Beginnings of Modern Psychology
- Continued
First Schools
•
•
•
Structuralism (Wundt) :
a. Metaphor was the periodic table of chemistry
b. Goal was the describe the structures of thought
Functionalism (James) :
Emphasis on function of mental processes
as compared to structures
Both Schools used Introspection:
Wundt’s Introspectionism:The method entails observing one’s
thought processes, but it was deemed important that a more
experienced introspectionist train a novice in the method
James : Less dogmatic in his approach.
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The Response: Behaviorism
•
Introspectionism was unsuccessful!
•
Watson – starts a new direction in psychology
Behaviorism (1913)
“Psychology as the behaviorist views it is a purely
objective experimental branch of natural science.
Its theoretical goal is the prediction and control of
behavior. Introspection forms no essential part of
its methods, nor is the scientific value of its data
dependent upon the readiness with which they
lend themselves to interpretation in terms of
consciousness.” – from Psychology as the
Behaviorist Views it.
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The Response Continued:
Four Principles of Behaviorism
1. Psychologists should focus only on that which is
available.
2. Psychologists should explain behavior, not
thought or consciousness.
3. Theories should be as simple as possible.
4. The overarching goal of psychology is to break
down behavior into irreducible constructs – the
building blocks of behavior. Watson’s candidate
was the conditioned reflex.
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Behaviorism’s Successes
• Offered the idea of the reflex as a basic unit of
behavior
• Pavlov’s Study of Classical Conditioning:
Unconditioned Stimulus, Unconditioned Response,
Conditioned Stimulus, Conditioned Response – the Classic
Dog Salivation Paradigm
• Operant Conditioning:
Learning whereby the animal (or person) makes a
response that has consequences (e.g., reward or
punishment). These consequences change the probability
that the response will be made again.
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How Do Cognitive Psychologists
Study the Mind?
•
•
•
•
•
•
What Behaviorism Couldn’t Do
Failures of Behaviorism to Account for
Human Behavior
The Computer Metaphor and Information
Processing
The Behaviorist Response
Abstract Constructs in Other Fields
So What, Finally, Is the Cognitive
Perspective?
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What Behaviorism Couldn’t Do.
• Lacked utility in WWII human factor applications
• Couldn’t deal with ethological principles (Lorenz):
• a. Fixed action patterns
Complex behaviors in which an animal engages despite very limited
opportunities for practice or reward. Usually taken as evidence for
innate or inborn learning.
• b. Critical periods
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 learning will be difficult or even impossible.
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Failures of Behaviorism to Account for
Human Behavior
•
Problem with human behaviors such as Language :
Chomsky’s Criticisms of Skinner’s Verbal Behavior
a. Whitehead’s problem of the ‘Scorpion on the Table’
b. Generative nature of language
•
Didn’t Explain Memory Phenomena such as Bousfield
(1953) demonstration of retrieval strategies.
Example - Try to recall ten minutes from now:
Lion, onion, Bill, firefighter, carrot, zebra, John, clerk,
Tim, nurse, cow.
©2004 Prentice Hall
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The Computer Metaphor and
Information Processing
• Importance of Metaphor in Psychological Theories
Descartes – Nervous System to Hydraulics
19th Century – Brain to a Telephone Switch Board
Hebb (1949) – Neural function to solenoids and capacitors
• 1950’s – Computer Metaphor for the Mind
1. Artificial Intelligence and computer usage of symbols
applied to psychology models
2. Computer use of representation of symbols and processes to
manipulate them give insight into study of the mind
3. Hardware/software division in computers applied to brain/
mind
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The Computer Metaphor - Continued
•The Information Processing Model:
An approach to studying the human mind. It assumes that humans are
processors of information, and that representations and processing
operating on them underlie cognition. Assumes also that information is
processed in stages.
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
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The Behaviorist Response
• Information Processing Models relay on abstract constructs
( theoretical sets of processes and representations that you
think are useful in explaining some data).
For example – short term memory
• Behaviorists 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
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Abstract Constructs in Other Fields
• Abstract Concepts are used freely and with
rigor in other fields
• Artificial Intelligence –
Newell and Simon (1956) program to prove
formal logic theorems
• Neuroscience –
Tying brain structure to behavioral problems
Ex. – Patient H.M. and the abstract concept
of Short Term Memory
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So What, Finally, Is the Cognitive
Perspective?
• Behaviorism could account for all human
abilities, especially language and memory
• Abstract constructs could help in
understanding
• Neuroscience and A.I. successfully use
abstract constructs
• The interactions of representations and
processes can be compared to a computer
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Cognitive Perspective - Continued
• Chief Assumptions
1.There are representations and
processes that operate on them
2.We can discover them
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