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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
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Learning
Three types of Learning
• Classical Conditioning
• Operant or Instrumental Learning
• Cognitive or Social Learning
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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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Demonstration
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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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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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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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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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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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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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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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One Final Thought on 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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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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Skinner’s Radical Behaviorism
B.F. Skinner believed that the most
powerful influences on behavior are its
consequences
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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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Reinforcement vs Punishment
• Reinforcement
• Anything that increases a behavior or
response
• Punishment
• Anything that decreases or stops a
behavior/response
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Types of Consequences
Reinforcement
Positive
Negative
(Add)
(Remove)
Apply reward to
increase behavior
Remove aversive
stimulus to
increase behavior
(e.g., Getting A’s
for studying hard) (e.g., Advil relieves
headache)
Punishment
Apply negative
consequence to
decrease
behavior
(e.g., Spanking)
Remove desirable
stimulus to
decrease behavior
(e.g., Time Out)
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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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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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Types of Reinforcers
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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Types of Reinforcers
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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Schedules 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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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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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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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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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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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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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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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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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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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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Using Classical and Operant Conditioning
to Initiate and Sustain Behavior Change
Classical Conditioning  connects command with behavior
• UCS = tug on leash or pressure on hind legs
• UCR = dog sits
• CS = command (i.e., “Rocky sit”)
• CR = dog sits
Operant conditioning  behavior is repeated
• Give praise or food reward following CR
• Use intermittent reinforcement to prevent extinction
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Cognitive
Learning Models
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Kohler: Insight Learning
Wolfgang Kohler
Disenchanted with behaviorists explanation for
learning
Believed that cognition, or mental processes
must be essential to learning
Observational studies of chimpanzees
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Insight Learning
Problem – bananas hung outside of
chimp’s reach
Initial solutions
Pile up boxes and climb on top
Use sticks to knock the fruit down
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Insight Learning
Insight learning
solve complex problems by combining simpler,
previously learned responses
Problem-solving occurs through sudden
reorganization of perceptions
Placed bananas higher up – neither
previously learned solutions sufficient to
get the fruit
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Insight Learning
When unable to reach the fruit
First – threw the sticks away and kicked the
wall
Later, piled up the boxes, grabbed the stick,
climbed on the boxes and knocked the fruit
down with the stick
Cannot be explained through either operant or
classical conditioning alone
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Kohler’s Chimps
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Tolman: Cognitive Maps
Cognitive maps
Mental representations or images that help
organisms navigate through the world
Reinforcement has a greater impact on
performance than on learning
i.e., reinforcement serves to motivate the
animal to demonstrate what it has learned
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Diagram of a Tolman Maze
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Cognitive Maps
Three groups of rats
1) No reinforcement
2) Reinforced on every trial
3) No reinforcement for first ten trials;
reinforced on all subsequent trials
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Error Curve
by Day and Food Deprivation
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Maze Learning
Food/ Goal
Box
Start
A
B
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Cognitive Maps
Tolman hypothesized that the rats developed
cognitive maps of the maze
i.e., Visual/spatial Image or representation of physical
space that is used to navigate through the
environment
Demonstrated latent learning – learning that
takes place in the absence of reinforcement
reinforcement necessary to demonstrate acquisition
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Bandura: Social Learning Theory
Observational Learning
Acquisition of behaviors that results from
observation rather than direct experience
E.g.,
Children learn do cartwheels and
handstands
Learn what clothes to wear to fit in (e.g.,
midriffs; low-riser jeans)
Learn aggressive behavior
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Social Learning Theory
Modeling – imitation and reproduction of
behaviors of models
Model must be salient (i.e., are attractive,
have high status, and are similar to
observer)
Parents, peers, siblings, celebrities
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Social Learning Theory
Vicarious reinforcement
Learn about the consequences of a behavior
by observing a model engage in the
behavior and experience consequences
Outcome Expectancies
Learned association between a specific
behavior and a specific consequence OR
Belief about the consequences of our behavior
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Social Learning Theory
Outcome expectancies
Alcohol makes me relaxed and sociable
Wearing brown polyester will make me a
social outcast
If I study for the exam, I will get a good grade
If I eat those cookies, I will feel good
Having sex without a condom will result in
enhanced pleasure
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Social Learning Theory
Positive outcome expectancies
Belief that the behavior will result in reinforcing
or rewarding outcomes
Negative outcome expectancies
Belief that the behavior will result in punishing
or negative outcomes
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Social Learning Theory
Expectancies influence subsequent
behavior
Positive expectancy (i.e., belief that behavior
results in reinforcing outcomes) engage in
or repeat behavior
Negative expectancy (i.e., belief that behavior
results in punishing outcomes)  avoid or
discontinue behavior
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Aggressive Behavior
Children observed a model behave
aggressively toward the BOBO doll
Were more likely to behave aggressively when
given the opportunity to play with the BOBO
doll
Especially when the model was reinforced for
his/her aggressive behavior
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Copyright © Allyn and Bacon 2006