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Chapter 6
Learning
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ISBN: 0-131-73180-7
Copyright © Allyn & Bacon 2007
Learning
Learning –
A process through which experience produces
lasting change in behavior or mental processes
This is in contrast with instinct (species-typical
behavior). Humans behavior is much more
influenced by learning than instinct compared
to animals.
Habituation (an example of simple learning)–
Learning not to respond to repeated
presentation of a stimulus
Copyright © Allyn & Bacon 2007
Learning
Mere exposure effect (another example of
simple learning)–
Learned preference for stimuli to which
we have been previously exposed
Behavioral learning –
Forms of learning that can be described
in terms of stimuli and responses
(e.g. classical and operant conditioning)
Copyright © Allyn & Bacon 2007
What Sort of Learning Does
Classical Conditioning Explain?
Classical conditioning is a
basic form of learning in which
a stimulus that produces an
innate reflex becomes
associated with a previously
neutral stimulus, which then
acquires the power to elicit
essentially the same response
Copyright © Allyn & Bacon 2007
The Essentials of Classical
Conditioning—Ivan Pavlov
Neutral stimulus –
Any stimulus that produces no
conditioned response prior to learning
Acquisition –
Initial learning stage in classical
conditioning; conditioned response
becomes elicited by the conditioned
stimulus
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The Essentials of Classical
Conditioning
Unconditioned
stimulus (UCS)
Unconditioned
response (UCR)
Conditioned
stimulus (CS)
Conditioned
response (CR)
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The Essentials of Classical
Conditioning
Unconditioned
stimulus (UCS)
Unconditioned
response (UCR)
The stimulus that elicits
an unconditioned
response
Conditioned
stimulus (CS)
Conditioned
response (CR)
Copyright © Allyn & Bacon 2007
The Essentials of Classical
Conditioning
Unconditioned
stimulus (UCS)
Unconditioned
response (UCR)
Conditioned
stimulus (CS)
The response elicited
by an unconditioned
stimulus without prior
learning
Conditioned
response (CR)
Copyright © Allyn & Bacon 2007
The Essentials of Classical
Conditioning
Unconditioned
stimulus (UCS)
Unconditioned
response (UCR)
Conditioned
stimulus (CS)
A previously neutral
stimulus that comes to
elicit the conditioned
response
Conditioned
response (CR)
Copyright © Allyn & Bacon 2007
The Essentials of Classical
Conditioning
Unconditioned
stimulus (UCS)
Unconditioned
response (UCR)
Conditioned
stimulus (CS)
Conditioned
response (CR)
A response elicited by a
previously neutral
stimulus that has
become associated with
the unconditioned
stimulus
Copyright © Allyn & Bacon 2007
Classical Conditioning
Prior to conditioning
Neutral stimulus
(tone)
(Orientation to sound
but no response)
Unconditioned stimulus
(food powder in mouth)
Unconditioned response
(salivation)
Conditioning
Neutral stimulus
CS (tone)
+
Unconditioned stimulus
(food powder)
Conditioned response
(salivation)
After conditioning
Conditioned stimulus
(tone)
Conditioned response
(salivation)
Copyright © Allyn & Bacon 2007
Classical Conditioning
Extinction –
Weakening of a conditioned response in
the absence of an unconditioned stimulus
Spontaneous recovery –
Reappearance of an extinguished
conditioned response after a time delay.
Usually this reappears at a lower
intensity.
Copyright © Allyn & Bacon 2007
(1)
Acquisition
(CS + UCS)
(2)
Extinction
(CS alone)
Rest period
Strength of the CR
(Weak)
(Strong)
Acquisition, Extinction, and
Spontaneous Recovery
(3)
Spontaneous
Recovery
(CS alone)
(Time)
Trials
Copyright © Allyn & Bacon 2007
Classical Conditioning:
Generalization and Discrimination
Stimulus generalization involves giving a
conditioned response to stimuli that are
similar to the CS
Stimulus discrimination involves responding to
one stimulus but
not another that is similar
Confusing stimuli may cause experimental
neurosis
John Watson/Rosalie Rayner and Little Albert
Copyright © Allyn & Bacon 2007
Applications of Classical Conditioning
Taste-aversion learning –
Biological tendency in which an organism
learns to avoid food with a certain taste
after a single experience, if eating it is
followed by illness (examples of John
Garcia’s study and chemotherapy).
Copyright © Allyn & Bacon 2007
How Do We Learn
New Behaviors by
Operant Conditioning?
In operant conditioning, the
consequences of behavior,
such as rewards and
punishments, influence the
chance that our behavior will
occur again
Copyright © Allyn & Bacon 2007
How Do We Learn
New Behaviors by
Operant Conditioning?
Trial-and-error learning –
Learner gradually discovers the correct
response by attempting many behaviors
and noting which ones produce the
desired consequences…Law of effect—
Edward Thorndike
Copyright © Allyn & Bacon 2007
Skinner’s Radical Behaviorism
B.F. Skinner (a radical behaviorist)
believed that the most powerful
influences on behavior are its
consequences; he called these
reinforcers…he developed the “Skinner
Box” or operant chamber (a box in which
an animal can press a lever for food).
Copyright © Allyn & Bacon 2007
The Power of Reinforcement
Positive reinforcers –
Stimulus presented after a response that
increases the probability of that response
happening again
Negative reinforcers –
Removal of an unpleasant stimulus, contingent
on a particular behavior. Again this increases
the probability that the behavior will occur
again.
Copyright © Allyn & Bacon 2007
The Power of Reinforcement
Primary reinforcers –
Reinforcers, such as food, water, and
sex, that have an innate basis because of
their biological value to an organism
Copyright © Allyn & Bacon 2007
The Power of Reinforcement
Secondary reinforcers –
Stimuli, such as money or tokens, that
acquire their reinforcing power by their
learned association with primary
reinforcers
(also called conditioned reinforcers)
Copyright © Allyn & Bacon 2007
Contingencies of Reinforcement
Continuous reinforcement –
Reinforcement schedule in which all correct
responses are reinforced…this is best for
teaching and learning new behaviors
Partial reinforcement –
Reinforcement schedule in which some, but
not all, correct responses are reinforced
(also called intermittent reinforcement)…this is
best to maintain behaviors already learned
Copyright © Allyn & Bacon 2007
Contingencies of Reinforcement
Extinction –
In operant conditioning, a process by
which a response that has been learned
is weakened by the absence or removal
of reinforcement
Copyright © Allyn & Bacon 2007
Schedules of Reinforcement
(intermittent or partial)
Ratio schedules –
Provide reward after a certain number of
responses
Interval schedules –
Provide reward after a certain time interval
Fixed Ratio (FR)
Variable Ratio (VR)
Fixed Interval (FI)
Variable Interval (VI)
Copyright © Allyn & Bacon 2007
Schedules of Reinforcement
Fixed Ratio (FR)
Variable Ratio
(VR)
Fixed Interval
(FI)
Variable Interval
(VI)
Rewards appear after a
certain set number of
responses…the rate of
responding is high
e.g. factory workers
getting paid after every
10 cases of product that
are completed
Copyright © Allyn & Bacon 2007
Schedules of Reinforcement
Fixed Ratio (FR)
Variable Ratio
(VR)
Fixed Interval
(FI)
Variable Interval
(VI)
Rewards appear after a
certain number of
responses, but that
number varies from trial
to trial…this keeps the
number of responses
high
e.g. slot machine payoffs
Copyright © Allyn & Bacon 2007
Schedules of Reinforcement
Fixed Ratio (FR)
Variable Ratio
(VR)
Fixed Interval
(FI)
Variable Interval
(VI)
Rewards appear after a
certain fixed amount of
time, regardless of
number of
responses…the rate of
response is low
e.g. weekly or monthly
paychecks
Copyright © Allyn & Bacon 2007
Schedules of Reinforcement
Fixed Ratio (FR)
Variable Ratio
(VR)
Fixed Interval
(FI)
Variable Interval
(VI)
Rewards appear after a
certain amount of time,
but that amount varies
from trial to trial…the
response rate can be
low or high but not as
high as VR
e.g. random visits from
the boss who delivers
praise
Copyright © Allyn & Bacon 2007
Premack Principle
David Premack…rats learned that their
running would be followed by an
opportunity to drink...so this principle
states that a more-preferred activity can
be used to reinforce a less-preferred
activity.
Copyright © Allyn & Bacon 2007
The Problem of Punishment
Punishment –
An aversive stimulus which diminishes
the strength of the response it follows
How does this differ from negative
reinforcement?
Copyright © Allyn & Bacon 2007
Punishment vs. Negative
Reinforcement
Negative
Reinforcement
Response
Consequence
Loud Noise
Press Lever
Loud Noise
Removed
Press Lever
Loud Noise
Applied
Punishment
No Noise
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The Problem of Punishment
Positive punishment –
The application of an aversive stimulus
after a response
Negative punishment (omission training) –
The removal of an appetitive stimulus
after a response
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Four Kinds of Consequences
STIMULUS
Positive or
appetitive
+
Present
Remove
Positive
Reinforcement
Bonus for working hard
leads to more hard work
Negative or
aversive
Punishment
Getting speeding ticket
leads to less speeding
Negative
Reinforcement
Omission
Training
Aspirin curing headache
causes more aspirin use
Missing dinner leads to
less loitering after
school
Copyright © Allyn & Bacon 2007
The Use and Abuse of Punishment
Power usually disappears when threat of
punishment is removed
Punishment
•
•
•
Often triggers aggression
May inhibit learning new and better responses
Is often applied unequally
When does punishment work?
It should be swift, certain, limited, target the
behavior…usually omission training is best
Copyright © Allyn & Bacon 2007
Operant and Classical Conditioning
Compared
Classical conditioning involves the
association of two stimuli (UCS + CS)
before the response or behavior. The
learner is passive.
Operant conditioning involves a reinforcing
(reward) or punishing stimulus after a
response or behavior. The learner is
active.
Copyright © Allyn & Bacon 2007
How Does
Cognitive Psychology
Explain Learning?
According to cognitive
psychology, some forms of
learning must be explained
as changes in mental
processes, rather than as
changes in behavior alone
Copyright © Allyn & Bacon 2007
How Does
Cognitive Psychology
Explain Learning?
Insight learning –
Problem solving occurs by means of a sudden
reorganization of perceptions (Gestalt
psychologist Wolfgang Kohler and chimpanzee
experiments)
Cognitive maps –
A mental representation of physical space
(Edward Tolman)…rats maneuvered blocked
paths, flooding, and no reward still meant
learning was taking place.
Copyright © Allyn & Bacon 2007
Observational Learning: Albert
Bandura’s Challenge to Behaviorism
Observational learning (social learning)–
Form of cognitive learning in which new
responses are acquired after watching
others’ behavior and the consequences
of their behavior (BoBo doll experiment
with children watching adults)
Copyright © Allyn & Bacon 2007
Brain Mechanisms and Learning
Long-term potentiation –
Biological process involving physical changes
that strengthen the synapses in groups of
nerve cells; believed to be the neural basis of
learning…
There may be two different circuits for learning in
our brains; different perspectives of learning
might be right in their own way…
Copyright © Allyn & Bacon 2007
End of Chapter 6
Copyright © Allyn & Bacon 2007