Transcript LEARNING

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LEARNING
A DEFINITION OF LEARNING
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
A relatively permanent change in behaviour
potential that results from experience.
 Learning
verses performance
 Experience required
 Internal processes (behaviour is the manifestation)
 Learning
reflects a change in the potential to behave.
 Motivation,
maturation, illness, fatigue may cause changes in
behaviour but this is not learning.
 Behavior
changes that learning causes are not always
permanent.
 New,
competing behaviors, may be learned.
HISTORICAL ORIGINS
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
Several schools of thought have contributed to the
the study of learning processes.
 Functionalism
 Behaviourism
 Associative
 Cognitive
Functionalism
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 Early
school of thought in psychology that emphasized
instinctive origins and adaptive function of behavior.
 Antecendents
Dualism
 Darwin’s Natural Selection

Descartes’ Dualism
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“Man as part machine”
René Descartes
(1594-1660)
Nonhuman
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Stimulus
Involuntary
Action
Human
Stimulus
Involuntary
Action
Voluntary
Charles Darwin
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Natural variation
Some characteristics are selected
John Dewey
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 Father
of functionalism
 Suggested that reflexive behaviors of lower animals
had been replaced in humans by the mind
 In
humans, the mind had evolved as the primary mechanism
for survival
 Mind enables individual to adapt to environment
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The main idea of Dewey’s functionalism was that the
manner of human survival differs from that of lower
animals.
William James
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 Argued
that the major difference between humans and
lower animals is in the character of their inborn or
instinctive motives
 Humans
possess greater range of instincts that guide
behavior than do lower animals

These include “social” instincts, which directly enhance our
interaction with the environment and our survival
 Instincts
are both purposeful and directional
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The concept of instincts was strongly criticized based
on:
 Anthropological
observation of differences in values,
beliefs, and behaviors among cultures
 Widespread and uncritical use of the instinct concept
did not advance the understanding of human behavior.
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By the 1920’s, psychologists had moved away from
the instinct explanation and began to emphasize the
learning process.
Psychologists who viewed experience as the major
determinant of human actions were called
Behaviorists
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
These criticisms lead to the Behavioral Revolution
Behaviorism
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 School
of thought that emphasizes the role of
experience in governing behavior
 Behaviorists believed that the important processes
governing behavior are learned
 Major goal of behaviorism was to the determine the
laws governing learning
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
An important influence on Behaviorism came from
Aristotle’s concept of Associationism
Associationism
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
Aristotle was the earliest advocate of
associationism.
 Aristotle’s
associationism had an important influence on
behaviorism.
 Aristotle proposed that associations develop from two
events that are contiguous, physically similar, or polar
opposites.
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
John Locke, a 17th century British philosopher,
expanded on Aristotle’s ideas
 Claimed
 All
that there are no innate ideas
ideas result from experience
 Distinguished
between simple ideas which are based
on sensory input and complex ideas which are
combinations of several simple ideas
David Hume
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 Proposed
three principles of association connect simple
ideas into a complex one:
 Resemblance
 Contiguity
 Cause
and Effect
Thorndike
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
Edward Thorndike
 Unlike
Locke and Hume, who were philosophers,
Thorndike was a scientist
 Work with cats in the puzzle box led to Law of Effect
 Law of Effect stated that a response made in the
presence of a stimulus that leads to a satisfying result
will strengthen the bond between the stimulus and the
response.
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 Law
of Readiness stated that the organism must be
motivated to develop an association or to exhibit a
previously established habit.
 It is noteworthy that, in Thorndike’s formulation, the
consequence or reward was merely a facilitator to
strengthen the stimulus-response relation.
 Future
behaviorists would hypothesize about the
importance of the role of the motivation
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
Thorndike also proposed the concept of Associative
shifting or the gradual changing of the stimulus
could result in the association of that response to a
totally new stimulus.
Pavlov
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Pavlov believed that rules of association determine
which behavior occurs in the learning situation.
 Was
trained as a physiologist studying digestion, using
the dog as a model
 He noticed that the dogs started to secrete stomach
juices before the food was placed into their mouths
 He concluded that the dogs had learned a new
behavior
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Unconditioned stimulus
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Unconditioned response
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An innate reaction to an unconditioned stimulus
Conditioned stimulus
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An environmental event that can elicit an instinctive reaction
without any experience
A stimulus that becomes able to elicit a learned response as a
result of being paired with an unconditioned stimulus
Conditioned response
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A learned reaction to a conditioned stimulus
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
Generalization
 Responding
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in the same manner to similar stimuli
Extinction
 The
elimination or suppression of a response caused by
the removal of the conditioned stimulus
Watson
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
John B. Watson demonstrated the importance of
Thorndike and Pavlov’s learning principles to human
behavior.
 His
belief that abnormal as well as normal behavior
can be the result of learning led to the Little Albert
Study.
Little Albert Study
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Subject: 9 month old boy (Albert)
UCS or US: loud noise
CS: White rat
Initially, the boy was not afraid of the rat. Then, each
time he reached out for the rat, Watson & Raynor
sounded a loud gong behind his back, causing a fear
response
Eventually, Albert showed a fear response to the white
rat alone
Thus, Watson & Raynor demonstrated that phobia
could be learned.
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One of Watson’s students, Mary Cover Jones,
demonstrated that phobia could be “unlearned”.
Peter and the Rabbit
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Subject: Three year old Peter
Problem: Peter was afraid of rabbit
Procedure: Mary Cover Jones first brought the
rabbit into a room where Peter was at ease and
eating.
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Eating produced a positive emotional state whereas the
rabbit produced a negative emotional state.
She kept a comfortable distance but gradually
brought the rabbit closer and closer. Eventually
Peter could touch the rabbit without fear.
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The process was called counterconditioning.
 Counterconditioning:
the elimination of a conditioned
response when the conditioned stimulus is paired with an
opponent or antagonistic unconditioned stimulus.
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This played an important role in the development of
the behavior modification technique of systematic
desensitization.
Are all forms of learning associative?
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Led to the Cognitive “Revolution”
Adding Cognition into the Picture
Thinking/Reasoning
Explicit
Habituation
Implicit
Conditioning
Semantic
Episodic
Skills
Classical
Instrumental
Multiple Forms of Learning
Sloman’s Evidence
1) Dissociations
“H.M.”
“Unconscious Sequence Learning”
2) Simultaneous Contradictory Belief
“Linda Problem”
“Visual Illusions”
H.M.
Sequence learning
Nissen & Bullemer (1987) –
Serial Reaction Time
A B
C
*
D
Experimental Group = fixed sequence
of locations
D–B–C–A–C–B–D–C–B–Acircular sequence, 10 times per block
Control Group = random sequence of
locations
Violated Sequence
Subjects are sensitive to the presence of the sequence even
when they deny knowing that there was a sequence
Linda Problem
Linda is 20 years old, single, outspoken, and very bright.
She majors in philosophy. As a student, she is deeply
concerned with issues of discrimination and social justice,
and participated in the Occupy Wall Street Movement.
Which of the following is more probable?
(1) Linda is a bankteller.
(2) Linda is a bankteller and a member of the NDP.
Müller-Lyer
Illusion
Why Study Animal Learning?
1) precise control
2) start simple
3) use potent stimuli
4) model behavioural dysfunctions
5) avoid subjective data
6) interest in its own right
Learning
3 Types of Questions?
1) Can it be learned?
2) What conditions encourage/hinder
learning?
3) What is the underlying mechanism?
Learned: Delayed Responding?
Rats: 10-s
Racoon:
25-s
Choice
Cue
Dog:Location
5-min
1
Human
Location
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Location
1-year:
24-s
Location
3
2-year: 50-s
6-year: 20-min
Hunter (1913)
Conditions: Delay of Reinforcement
Grice – (1948)
Choice
Delay
Goal
Start
Reward
or No
Reward
Grice (1948) Results
1.2
s
100
90
80
70
60
50
40
30
20
2s
5s
Trials
700
625
550
475
400
325
250
175
100
10s
25
Percent Correct
0s 0.5s
Mechanism: Insight or Trial and Error?
Kohler (1914)
Is Sultan reasoning
through
to the solution?