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PSY 402
Theories of Learning
Chapter 1 – What is Learning?
What is 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.
Three Kinds of Learning
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Adaptation to the environment
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Classical conditioning
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Habituation & sensitization
Also known as Pavlovian conditioning,
respondent conditioning, S-S learning.
Instrumental or operant conditioning
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Also known as S-R learning.
Roots of Learning Theory
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The discovery of reflexes
Functionalism
British Associationists
1.3 (A) René Descartes; (B) René Descartes came up with the concept of reflex action
Man, the Machine
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Descartes proposed that the body operates
mechanically via reflex actions, similar to
machinery.
Reflexes are activated by stimuli in the
environment.
A reflex connects a stimulus (S) with a
response (R).
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This concept is used throughout learning theory.
The Role of “Mind”
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Descartes proposed that the mind could
overrule the action of bodily reflexes.
Hobbes disagreed, arguing that the mind too
operated reflexively.
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Hedonism –all human thought is governed by
seeking pleasure and avoiding pain.
De la Mettrie observed that humans and
animals are similar, and the body can affect
the mind, as well as vice versa.
1.4 Two famous British Empiricists
John Locke
David Hume
British Empiricists (Associationists)
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Locke, Hume, Berkeley
The mind is a blank slate (tabula rasa) at birth.
Knowledge is built up from sense impressions
combined to form complex ideas.
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Associations bind these impressions together.
Complexity is built from simple parts
Example of the apple – sweetness, redness,
roundness, associated with taste, smell to form
the idea (concept) of an “apple.”
1.5 Immanuel Kant
Nature vs. nurture
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Nativists (nature) vs. empiricists (nurture).
Rationalism – Kant argued that the mind is prepared
to respond to its environment at birth.
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A priori assumptions or ideas organize experience.
We are born knowing about causality, substance, and a
variety of other concepts.
This idea is called preparedness.
The extreme version of this philosophy is called
structuralism.
1.6 (A) Charles Darwin; (B) Drawing from one of Darwin’s notebooks
Evolution & Natural Selection
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Darwin – there is a continuity between
humans and animals and both struggle for
survival.
Perhaps the mind itself has evolved.
Functionalism – because behavior promotes
survival, we can study behavior to understand
its adaptive function.
Functionalists
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Dewey – lower animals have reflexes,
humans have a flexible mind
James – people have instincts, not reflexes
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The difference is whether the behavior can be
changed or interrupted
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.
Labeling everything an instinct doesn’t aid
understanding much.
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Bernard cataloged 2000+ instincts
Comparative Psychology
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Romanes collected stories of animal behavior.
Morgan – observed that dogs were not as clever as
humans in performing certain tasks.
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Complex animal behaviors may be built from laboriously
learned simple processes.
We cannot judge from the observed result but from the
process of learning.
Morgan’s canon – behavior should not be explained
by a complex process if a simpler one works
(parsimony of explanation).
1.7 (A) C. Lloyd Morgan; (B) Morgan’s dog, Tony
Behaviorism
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A search for the laws governing learning.
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Associations are formed based on:
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Emphasis on experience.
Avoidance of mentalistic concepts.
Resemblance (similarity)
Contiguity in time or place
Cause and effect
We can generalize from animals to humans.
Early Experiments
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Thorndike – S-R learning with cats in puzzle box.
Pavlov – S-S learning with dogs salivating for meat
powder.
Watson – S-S learning with humans, such as “Little
Albert” and the white rabbit.
Skinner – S-R learning with rats in “Skinner boxes”
(operant chambers). A “radical Behaviorist”.
Tolman – the “gadfly” of Behaviorism, arguing that
even rats have minds and think about their actions.
1.8 (A) Edward Thorndike; (B) Two puzzle boxes Thorndike used to study the intelligence of cats
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.
1.9 (A) Ivan Pavlov; (B) Pavlov’s classical conditioning set-up
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.
Pavlov’s Studies
1.10 John B. Watson
Watson & Raynor
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Human fears can be acquired through
Pavlovian (classical) 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
Little Albert
1.11 (A) B. F. Skinner; (B) A modern “Skinner box”
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.
The Operant vs Respondent Distinction
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How voluntary is behavior?
Operant vs respondent distinction:
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Respondent behavior is controlled by what
happens first (antecedents), elicited by stimuli in
the environment.
Operant behavior is controlled by the
consequences of behavior in the past, emitted by
the organism based on prior experience.
1.12 Edward C. Tolman developed “operational behaviorism”
Tolman’s Operational Behaviorism
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Tolman proposed that behavior can be
described in terms of unobservable mental
constructs.
Thirst is a construct that relates antecedents to
observed behavioral responses.
Constructs are widely used in psychology.
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Cognitive psychology emerged out of Tolman’s
early research demonstrating constructs in rats.
1.13 A theoretical construct like “thirst” is not directly observable (Part 1)
1.13 A theoretical construct like “thirst” is not directly observable (Part 2)