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Chapter 6
Learning
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Copyright © Allyn and Bacon 2006
Learning
Learning –
A process through which experience
produces lasting change in behavior or
mental processes
Behavioral learning –
Forms of learning that can be described
in terms of stimuli and responses
(e.g. classical and operant conditioning)
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Copyright © Allyn and Bacon 2006
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
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Copyright © Allyn and Bacon 2006
The Essentials of Classical
Conditioning
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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Copyright © Allyn and Bacon 2006
The Essentials of Classical
Conditioning
Unconditioned
stimulus (UCS)
Unconditioned
response (UCR)
The stimulus that elicits
an unconditioned
response
Conditioned
stimulus (CS)
Conditioned
response (CR)
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Copyright © Allyn and Bacon 2006
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)
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Copyright © Allyn and Bacon 2006
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)
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Copyright © Allyn and Bacon 2006
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
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Copyright © Allyn and Bacon 2006
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)
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Copyright © Allyn and Bacon 2006
Classical Conditioning
Extinction –
Weakening of a conditioned association
in the absence of an unconditioned
stimulus or reinforcer
Spontaneous recovery –
Reappearance of an extinguished
conditioned response after a time delay
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(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
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Copyright © Allyn and Bacon 2006
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 to stimuli that are similar
Confusing stimuli may cause
experimental neurosis
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Copyright © Allyn and Bacon 2006
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
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Copyright © Allyn and Bacon 2006
A Challenge to Pavlov
Why are some stimuli-consequence
combinations readily learned while other
combinations are highly resistant to
learning?
What any organism can or cannot learn in
a given setting is due in part to its
evolutionary history
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Copyright © Allyn and Bacon 2006
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
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Copyright © Allyn and Bacon 2006
Skinner’s Radical Behaviorism
B.F. Skinner believed that the most
powerful influences on behavior are its
consequences
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Copyright © Allyn and Bacon 2006
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
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Copyright © Allyn and Bacon 2006
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
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The Power of Reinforcement
Primary reinforcers –
Reinforcers, such as food and sex, that
have an innate basis because of their
biological value to an organism
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Copyright © Allyn and Bacon 2006
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)
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Copyright © Allyn and Bacon 2006
Contingencies of Reinforcement
Continuous reinforcement –
Reinforcement schedule in which all
correct responses are reinforced
Partial reinforcement –
Reinforcement schedule in which some,
but not all, correct responses are
reinforced
(also called intermittent reinforcement)
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Copyright © Allyn and Bacon 2006
Class Demonstration
Establishing a behavior using operant
conditioning
• Select a target behavior; be very specific
• Using shaping  reinforcing successive
approximations of the behavior
• Be careful to reinforce only the target behavior
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Copyright © Allyn and Bacon 2006
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
How does this differ from extinction in
classical conditioning?
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Schedules of Reinforcement
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)
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Copyright © Allyn and Bacon 2006
Schedules of Reinforcement
Fixed Ratio (FR)
Variable Ratio
(VR)
Fixed Interval
(FI)
Rewards appear after a
certain set number of
responses
e.g. factory workers
getting paid after every
10 cases of product are
completed
Variable Interval
(VI)
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Copyright © Allyn and Bacon 2006
Schedules of Reinforcement
Fixed Ratio (FR)
Variable Ratio
(VR)
Fixed Interval
(FI)
Rewards appear after a
certain number of
responses, but that
number varies from trial
to trial
e.g. slot machine payoffs
Variable Interval
(VI)
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Copyright © Allyn and Bacon 2006
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
e.g. weekly or monthly
paychecks
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Copyright © Allyn and Bacon 2006
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
e.g. random visits from
the boss who delivers
praise
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The Problem of Punishment
Punishment –
An aversive stimulus which diminishes
the strength of the response it follows
How does this differ from negative
reinforcement?
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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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Copyright © Allyn and Bacon 2006
Types of Punishment
Positive punishment –
The application of an aversive stimulus
after a response
Negative punishment –
The removal of an attractive stimulus
after a response
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Four Kinds of Consequences
GOAL
STIMULUS
Increase
Behavior
Decrease
Behavior
Positive
(Add)
Negative
(Subtract)
Positive
Reinforcement
Negative
Reinforcement
Bonus for working hard Aspirin relieving headache
leads to more hard work leads to more aspirin use
Positive
Punishment
Positive
Punishment
Getting speeding ticket
leads to less speeding
Missing dinner leads to
less staying out late
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Copyright © Allyn and Bacon 2006
Problems 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?
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Alternatives to Punishment
Extinction
Reinforcing preferred activities
Premack principle
Prompting and shaping
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Operant and Classical Conditioning
Compared
Classical conditioning involves the
association of two stimuli (UCS + CS)
before the response or behavior
Operant conditioning involves a reinforcing
(reward) or punishing stimulus after a
response or behavior
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Copyright © Allyn and Bacon 2006