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Learning
Chapter 6
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Definition: Learning
• “Learning” is defined in psychology as ‘a
relatively permanent behavior change as
a result of experience.
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Learning
How Do We Learn?
Classical Conditioning
 Pavlov’s Experiments
 Pavlov’s Legacy
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Learning
Operant Conditioning
 Skinner’s Experiments
 Skinner’s Legacy
 Contrasting Classical & Operant
Conditioning
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Learning
Biology, Cognition, and Leering
 Biological Constraints on Conditioning
 Cognitive Processes and Classical
Conditioning
 Cognitive Processes and Operant
Conditioning
 Learning by Observation
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How Do We Learn?
• By linking events that occur close
together, humans and other animals
exhibit associative learning.
– This process of learning associations is called
conditioning.
• There is also cognitive learning,
– the acquisition of mental information by
observing events, watching others, or through
language.
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Classical Conditioning
• A stimulus is an event or situation that
evokes a response.
• In classical conditioning, we learn to
associate two stimuli; the unconditioned
response to one stimulus becomes the
conditioned response to the other.
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Classical Conditioning: Pavlov’s
Classic Experiment
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Classical Conditioning
• The neutral stimulus (NS) elicits no response
before conditioning.
• The unconditioned stimulus (US) is a stimulus
which triggers a reflex (automatic response, UR)
without conditioning.
• The conditioned stimulus (CS) is an originally
neutral stimulus that, after association with a US,
comes to trigger a CR.
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Classical Conditioning
• The unconditioned response (UR) is an
unlearned, natural response to a US
• The conditioned response (CR) is a learned
response to a previously neutral stimulus (CS). It is
the same action as the unconditioned response,
except that it is now triggered by the formerly neutral
stimulus (now CS).
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Conditioning Processes
• Pavlov and his associates identified five
major conditioning processes:
– Acquisition
– Extinction
– Spontaneous recovery
– Generalization
– Discrimination
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Acquisition
• Acquisition is the first stage in classical
conditioning – where a NS is linked with a US
that the NS begins triggering the CS
Why are our bodies set up to be conditioned?
Classical conditioning helps us prepare for good
and bad events.
This is why the neutral stimulus must happen
first for conditioning to occur; it is the event we
use as a warning for the bad, a clue that helps
us find the good!
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Extinction and Spontaneous Recovery
• If, following acquisition, the CS occurs
repeatedly without the US, it can lead to
extinction, the weakening of the CR.
• After a delay (a few hours more), however, the
CS may elicit a spontaneous recovery of a
(weakened) CR
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Generalization
• Generalization: after conditioning, an
organism may respond similarly to stimuli
that resemble the CS
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Generalization
• Child abuse can lead to general
hypersensitivity to the faces of any angry
person, not just their abusers.
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Discrimination
• Organisms also learn to discriminate, or
distinguish, between a CS and other
stimuli.
• Consider your responses to a guard dog
and a guide dog: would they both make
your heart pound with fear?”
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Pavlov’s Legacy
1. Many responses can be classically
conditioned in many other creatures
– I remember the ‘worm runners’ journal—had
articles about conditioning worms.
2. Learning can be studied objectively
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Can Pavlov’s work help us
understand emotions?
• Little Albert
– John B. Watson and Rosalie Rayner (1920) worked
with 11-month old boy
– Little Albert feared loud noises but not white rats
– Watson presented him with white rat
• just as he reached out to touch it, Watson made a very loud
noise just behind Little Albert’s head
• After 7 repetitions, Little Albert burst into tears at sight of rat
– 5 days later, he had generalized this fear to a rabbit, a dog,
and a sealskin coat
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Operant Conditioning
• Classical conditioning involves an automatic
response to a stimulus
• Operant Conditioning involves associating a
behavior with consequences.
• Consequences:
– Reinforcers following a behavior make that behavior
more likely to happen again, and
– Punishments following a behavior make it less likely
to recur.
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Operant Conditioning
If a seal is an aquatic exhibition balances a a ball on its
nose, it receives a food reward which increase the
likelihood that he will balance the ball again.
(a) Response:
Balancing a ball
(b) Consequence:
Receiving Food
(c) Behavior strengthened
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B. F. Skinner’s Experiments
• Skinner designed an operant chamber (a
Skinner Box) – a box with a recording device to
track how often an animal presses a bar to
obtain reinforcement – any event or other
consequence that strengthens the behavior it
follows.
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Reinforcement for the Individual
• What is reinforcing to one individual?
• Can vary by situation – a cold drink is
reinforcing if you are hot, but not if you
are cold
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Shaping Behavior
• Shaping: gradually guiding actions closer
and closer toward a desired behavior,
using reinforcement.
• Using successive approximations, one
rewards responses that are ever-closer to
the desired behavior.
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Types of Reinforcers
• Positive reinforcement: anything that
strengthens a response
• Negative reinforcement: anything that,
when removed, strengthens response
– Negative reinforcement is NOT a punishment
• If I say, you are not going out tonight because you
didn’t clean your room—that is punishment
• If I say, you can go out when you clean your
room—that is negative reinforcement
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Types of Reinforcers
• A primary reinforcer is innately reinforcing
(e.g., giving food when hungry, or alleviating a
headache).
• A conditioned (secondary) reinforcer gains its
reinforcing power through links with a primary
reinforcer—money is a secondary reinforcer.
• Most organisms require immediate
reinforcement, but humans can also use
delayed reinforcement
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Reinforcement Schedules
• Continuous reinforcement – reinforcing
desired response every time it occurs
– Learning occurs rapidly, but so does extinction
• Partial (intermittent) reinforcement –
reinforcing a response only part of the time
– Learning is slower but increased resistance to
extinction
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Partial Reinforcement Schedules
for Operant Conditioning
• Fixed-ratio schedule – reinforces response
only after fixed number of responses
• Variable-ratio schedule – reinforces response
after an unpredictable number of responses
– Produces high rates of responding
• Fixed-interval schedule – reinforces response
only after a specified time has elapsed
– Produces choppy start-stop pattern
• Variable-interval schedule – reinforces
response at variable time intervals
– Produces slow, steady responding
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Punishment
• A punishment is an event that decreases
the frequency of the behavior it follow
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Physical Punishment for Children:
Why Not?
1. Punishment teaches discrimination
•
rule learned: don’t swear at home but what you
desired was that they not swear at all.
2. Punishment can teach fear
3. Physical punishment may increase
aggressiveness
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Physical Punishment for Children
• A single swat or two may be effective for 2
to 6-year-olds if:
– The swat is only used for backup when milder
tactics fail
– The swat is combined with reasoning and
reinforcing
• Remember:
– Punishment tells you what not to do,
reinforcement tells you what to do
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Skinner’s Legacy: Controversy
Skinner argued that behaviors were shaped by external
influences
 instead of inner thoughts and feelings.
 Critics argued that Skinner dehumanized people by neglecting
their free will.
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Applications of Operant Conditioning
• In school: use individualized shaping to
reinforce students starting with their
current level of performance.
• At work: reinforce, even with a ‘good job’
for specific behaviors and achievements
• At home: be careful not to reward
tantrums by giving in.
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Biological Constraints on
Conditioning
• Each species is thought to come prepared
to learn those things crucial to its survival.
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Limits on Classical Conditioning
• All conditioned stimuli are not equal
• Rats avoided a taste – but not sights or
sounds – associated with being sick
– Taste aversion: animals are biologically
predisposed to learn by eating food, not by
the appearance of food, which foods make us
sick.
• Is that why dogs and cats will eat their own vomit?
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Limits on Operant Conditioning
• Animals can most easily learn behaviors
that draw on their predispositions
– YES: Train a pigeon to flap wings to avoid a
shock, and peck to obtain food
– NO: Train a pigeon to peck to avoid a shock,
and to flap wings to obtain food
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Cognitive Processes and Classical
Conditioning
• Behaviorism: The view that (1) psychology
should be an objective science that (2) studies
behavior without reference to mental processes
– Founded by Pavlov, Watson, and Skinner
– Most psychologists today agree with (1) but not (2)
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Cognitive Processes and Operant
Conditioning
• B. F. Skinner tried to downplay the role of
cognitive processes. However, they
cannot be ignored
– Rats exploring a maze develop a cognitive
map, a mental representation of the maze.
– Rats with experience in the maze exhibit
latent learning of the maze’s layout
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Cognitive Processes and Operant
Conditioning
• Excess rewards can destroy intrinsic
motivation, the desire to perform a
behavior for its own sake.
• This is in contrast to extrinsic motivation,
in which behavior is performed to gain
reward or avoid punishment.
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Learning By Observation
• Cognition is a factor in observational
learning,
– in which humans and some other animals
learn by watching and imitating
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Observational Learning
• Bandura’s (1961) Bobo doll experiments showed
the importance of modeling
– the process of observing and imitating a specific
behavior
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Mirrors in the Brain
• Mirror neurons fire when we perform
certain actions and when we observe
others performing those actions
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Mirrors in the Brain
• If we see a loved one in pain, our face
mirrors their expression, and so does our
brain
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Applications of Observational
Learning
• Models of prosocial behavior – can have
prosocial effects.
• Unfortunately, antisocial behavior can also be
learned by observation
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