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Chapter 6
Learning
Copyright © Allyn & Bacon 2007
What is learning?
See handout 6-2
With your aisle partner, discuss whether
you think each of the scenarios is an
example of learning.
Copyright © Allyn & Bacon 2007
Learning
Learning –
A process through which experience
produces lasting change in behavior or
mental processes
Hilgard and Bower’s definition: the relatively permanent
change in behavior in a given situation brought about
be repeated experiences in that situation, provided that
the behavior can’t be explained by native response
tendencies, maturation, or temporary states
(fatigue, drugs, etc.)
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Learning
In this chapter we will not learn about:
Instincts: they are innate, NOT learned
Maturation: normal stages will be
covered in an upcoming chapter
Memory: covered in a previous chapter
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Simple Learning
Mere exposure effect –
Learned preference for stimuli to which
we have been previously exposed (e.g.
advertising)
Habituation –
Learning not to respond to repeated
presentation of a stimulus
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Complex Learning
Behavioral learning –
learning achieved through manipulation
of stimuli and responses
(e.g. classical and operant conditioning)
B. F. Skinner’s behaviorist manifesto:
1. psychology’s concern should be behavior
2. methods should be objective, not introspective
3. goal should be “prediction and control of behavior”
rather than understanding of mental events
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The Essentials of Classical
Conditioning
Neutral stimulus –
produces no conditioned response (CR)
prior to learning (Pavlov)
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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)
The stimulus that elicits
an UCR
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 response elicited
by a UCS without prior
learning
Conditioned
stimulus (CS)
Conditioned
response (CR)
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The Essentials of Classical
Conditioning
Unconditioned
stimulus (UCS)
Unconditioned
response (UCR)
Conditioned
stimulus (CS)
A previously neutral
stimulus that comes to
elicit the CR
Conditioned
response (CR)
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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 UCS
Copyright © Allyn & Bacon 2007
Classical conditioning
Close your eyes and imagine you are
floating in warm ocean waters. Relax
In this scene, what is the UCS, UCR, CS,
and CR?
Let’s practice this with a handout.
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Classical conditioning
Acquisition –
Initial learning stage; CR (salivating)
becomes elicited by the conditioned
stimulus (CS)
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Classical Conditioning
Extinction –
Weakening of a conditioned association
in the absence of a UCS
-many of you no longer respond to the horn.
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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Classical Conditioning:
Generalization and Discrimination
Stimulus generalization: giving a CR to
stimuli that are similar to the CS
(Little Albert)
Stimulus discrimination: responding
to one stimulus but
not to stimuli that are similar
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Applications of Classical Conditioning
Taste-aversion learning –
learning to avoid food after a single
experience, if eating it is followed by
illness (caveat: if you get sick DIRECTLY after eating a food, you
often won’t get taste aversion)
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A Challenge to Pavlov
Why are some associations readily learned
while others are resistant to learning?
Contiguity: the nearer the better
The Seahawk-balloon pairing might be too far apart
Contingency: the more regular the better
The UCS must ALWAYS be paired with the CS during
acquisition
Novelty: the newer the better
It would be hard to make a CS out of the school bell,
because you hear it twelve times a day. It’s not new.
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Association Principle
Think of your favorite soup:
Now imagine the soup is served to you in
an ordinary bowl, but has been stirred by
a thoroughly washed, used flyswatter.
How much would you like to eat that
soup, on a scale of 1=not at all to 9=very
much?
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If that flyswatter were brand new, how
much would you like to eat the soup, on a
scale of 1=not at all to 9=very much?
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If the soup were first stirred with a
thoroughly washed but used comb, how
much would you like to eat that soup, on
a scale of 1=not at all to 9=very much?
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If the soup were served in a thoroughly
washed, used dog bowl, how much
would you like to eat that soup, on a
scale of 1=not at all to 9=very much?
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Of 143 participants…
1. 82% gave a four or lower
2. 58% gave a four or lower
3. 76% gave a four or lower
4. 71% gave a four or lower
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Association principle
Linking two events that occur close
together but are unrelated
Association principle applies in both CC
and OC
Accounts for superstition
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Before we get to operant
conditioning…
Can I have two volunteers for an
experiment? You will need to leave the
room for a few moments as I prepare the
experiment.
Shaping –
reinforcers guide behavior toward closer
and closer versions of the desired
behavior.
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The Skinner Box
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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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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
Copyright © Allyn & Bacon 2007
Skinner’s Radical Behaviorism
B.F. Skinner believed that the most
powerful influences on behaviors are
their consequences
Based ideas on Thorndike’s Law of Effect:
behaviors followed by favorable
consequences become more likely, and
behaviors followed by unfavorable
consequences become less likely.
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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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Contingencies of Reinforcement
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The Power of Reinforcement
Primary reinforcers –
Reinforcers, such as food and sex, that
are innate because of their biological
value
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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)
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The Problem of Punishment
Punishment –
A 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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The Problem of Punishment
Positive punishment –
The application of an aversive stimulus
after a response
Omission training (negative punishment) –
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
Omission
Training
Negative
Reinforcement
Missing dinner leads to
less staying out late
Aspirin curing headache
causes more aspirin use
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Copyright © Allyn & Bacon 2007
CC or OC
Copyright © Allyn & Bacon 2007
Let’s practice
With an aisle partner, complete the back of
the handout I gave you last week.
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Yay!
If you know the difference between
punishment and negative reinforcement,
you are smarter than Bill Murray.
Copyright © Allyn & Bacon 2007
Contingencies of Reinforcement
Continuous reinforcement –
Reinforcement schedule in which all
desired responses are reinforced
Partial reinforcement –
Reinforcement schedule in which some,
but not all, desired responses are
reinforced
(also called intermittent reinforcement)
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Schedules of Partial
Reinforcement
Ratio schedules –
Provide reward after a certain number of
responses; produce higher response rates
than…
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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Schedules of Reinforcement
Fixed Ratio (FR)
Variable Ratio
(VR)
Fixed Interval
(FI)
Variable Interval
(VI)
Rewards appear after a
certain set number of
responses
e.g. factory workers
getting paid after every
10 cases of product are
completed
Effect: activity slows after
reinforcer and then picks up;
goes extinct quickly without
constant reinforcement
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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
e.g. slot machine payoffs
Effect: responding rate is high and
stable; most resistant to extinction
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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
Effect: activity increases as
deadline nears; can cause fast
extinction
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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
Effect: steady activity results, good
resistance to extinction
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As a rule:
Variable is more resistant to extinction than fixed
Ratio is more resistant to extinction than interval
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Reinforcement schedules
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Let’s try some practice figuring out
reinforcement schedules
Handout
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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
Reinforcement should be chosen over
punishment whenever possible
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Alternatives to Punishment
Reinforcing preferred activities
Premack principle: a more preferred activity
can reinforce a less preferred activity
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
A video that summarizes classical and
operant conditioning.
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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
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How Does
Cognitive Psychology
Explain Learning?
Insight learning –
Problem solving occurs by means of a
sudden reorganization of perceptions
Cognitive maps –
A mental representation of physical
space (contrasted with chained
association [knowing the turns])
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Cognitive Maps
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Observational Learning: Bandura’s
Challenge to Behaviorism
Observational learning –
Form of cognitive learning in which new
responses are acquired after watching others’
behavior and the consequences of their
behavior—can be prosocial or antisocial
Bandura’s Doll Experiment; more video
Latent learning: learning you didn’t know you’d
learned until required to apply it.
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Brain Mechanisms and Learning
Long-term potentiation –
Physical changes that strengthen the
synapses in groups of nerve cells; the
neural basis of learning
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Operant and Classical Conditioning
In action
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End of Chapter 6
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