KleinCh1

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Introduction to Learning
Chapter 1
A Definition of Learning
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Learning is:
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An experiential process
Resulting in a relatively permanent
change
Not explained by temporary states,
maturation, or innate response
tendencies.
Three Limits on the Definition
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The change that occurs during
learning is a potential for behavior
that depends on other conditions.
Learning is not always a permanent
change.
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What can be learned can be unlearned.
Changes also occur for other
reasons – maturation, motivation.
Roots of Behavior Theory
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Functionalism – behavior promotes
survival, study behavior to
understand its adaptive function.
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Dewey – lower animals have reflexes,
humans have a flexible mind
James – people have instincts
Brucke – internal biochemical forces
motivate behavior in all species.
Criticisms of Functionalism
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The variety of behavior across
cultures is inconsistent with
universal human instincts.
Infants seem to have few innate
instincts (only fear, rage, love?).
Labeling everything an instinct
doesn’t aid understanding much.
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Bernard cataloged 2000+ instincts
Behaviorism
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A search for the laws governing
learning.
Emphasis on experience.
Avoidance of mentalistic concepts.
Based on Aristotle’s idea of the
association of ideas.
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In order for two ideas to become
associated, they must be paired
together in time (temporally).
British Associationists
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Locke – thinking consists of:
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Simple ideas – passive impressions
received by the senses.
Complex ideas – the combination
(association) of simple ideas (a rose).
Hume – associations are based on:
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Resemblance (similarity)
Contiguity in time or place
Cause and effect
Thorndike’s Puzzle Box
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http://www.youtube.com/watch?v=
BDujDOLre-8
Thorndike’s Puzzle Box
Learning Curve for Cats in Box
Thorndike’s Laws
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Also called S-R learning.
Law of effect – A chance act
becomes a learned behavior when a
connection is formed between a
stimulus (S) and a response (R)
that is rewarded.
Law of exercise – the S-R
connection is strengthened by use
and weakened with disuse.
Thorndike’s Laws (Cont.)
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Law of readiness – motivation is
needed to develop an association or
display changed behavior.
Associative shifting – a learned
behavior (response) can be shifted
from one stimulus to another.
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Once a behavior is learned, the
stimulus is gradually changed.
Fish + “stand up”, then “stand up”
alone.
Pavlov’s Studies
Pavlov’s Conditioned Reflex
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Conditioning -- a stimulus that
initially produces no response can
acquire the ability to produce one.
Learning occurs through pairing in
time and place of one stimulus with
another stimulus that produces a
response.
This is a kind of associative shifting,
but the response is involuntary.
Terminology of Conditioning
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Unconditioned stimulus (US or UCS)
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Produces a reflexive response without
learning.
Unconditioned response (UR or
UCR)
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The response that occurs, typically a
reflex, involuntary and automatic.
More Terminology
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Neutral stimulus
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Conditioned stimulus (CS)
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A stimulus not capable of producing an
unconditioned response.
A previously neutral stimulus that has
acquired the ability to evoke a
response.
Conditioned response (CR)
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The learned response, similar to the
UCR, an involuntary reflex.
Two Examples
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http://www.youtube.com/watch?v=
bOMMy1cmamE&feature=related
http://www.youtube.com/watch?v=
F-S2g8CXUAk&feature=related
Prior to conditioning
Neutral stimulus
(tone)
(Orientation to sound
but no response)
UCS
(food powder in mouth)
UCR
(salivation)
Conditioning
Neutral stimulus
CS (tone)
+
UCS
(food powder)
CR
(salivation)
After conditioning
CS
(tone)
CR
(salivation)
Conditioning Processes
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Stimulus generalization – stimuli
like the CS become able to evoke
the conditioned response.
Extinction – if the UCS and CS are
not paired, the CS loses its ability to
produce a conditioned response.
Spontaneous recovery – an
extinguished CS briefly returns but
quickly goes away again.
Acquisition, Extinction, and
Spontaneous Recovery
Little Albert
Watson & Raynor
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Human fears can be acquired
through Pavlovian conditioning.
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Rat paired with loud noise
Stimulus generalized to other white
objects (white rabbit, white fur coat)
Mary Cover Jones developed
counterconditioning -- a technique
for eliminating conditioned fears.
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Acquisition of fear-inhibiting response
Ethics of Learning Research
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Animals and humans are now
protected by oversight and ethical
guidelines.
Pain or injury to animals must be
weighed against and justified by the
knowledge to be gained.
Electric shock typically is
uncomfortable and upsetting but
not physically harmful.
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