Transcript Wade Chapter 8 Learning

OPERANT CONDITIONING
Chapter 9 Section 2
1
OPERANT CONDITIONING
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Learn to do, or not do, things based on the
consequences of the behavior
Behavior operates on, or manipulates, the
environment
Voluntary responses are acquired or
conditioned
THE BIRTH OF RADICAL
BEHAVIORISM
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Edward Thorndike (1998)
As a doctoral candidate Thorndike conducted a
classic experiment called the “puzzle box”. He
placed a cat in a specially designed box and
allowed it to learn the correct sequence of
behaviors to escape from the box and retrieve a
food reward.
The cat at first would randomly perform a
number of behaviors.
THORNDIKES’ PUZZLE BOX
Fig 6.8
LAW OF EFFECT
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According to the law of effect, responses
followed by satisfaction are more likely to
reoccur in the future. Responses that produce
a discomforting effect become less likely to
occur again in that situation.
THE CONSEQUENCES OF BEHAVIOR
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From Skinner’s perspective a response
(“operant”) can result from
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Reinforcement
Punishment
THE CONSEQUENCES OF BEHAVIOR--REINFORCEMENT
Reinforcement ~ Strengthens the response or makes it more likely to
recur. When the dog begs for food at the table, and you give him/her a scrap, the
dog will most likely keep begging for food.
THE CONSEQUENCES OF BEHAVIOR-PUNISHMENT
Punishment ~ Weakens the response or makes it less likely to recur.
Any
Aversive (unpleasant) stimulus or event may be a punisher. If your dog begs for
food from the table and you refuse, his/her is not likely to continue to beg in the
future.
PRIMARY AND SECONDARY REINFORCERS
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Reinforcers can be categorized into two groups:
Primary Reinforcers
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Any stimulus or event that is inherently reinforcing,
typically satisfying some physiological need; such as
food, water, sleep.
Secondary Reinforcers
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A stimulus that has acquired reinforcing properties
through association with other primary Reinforcers.
Such as money, grades, etc.
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How does a secondary reinforcer acquire those
properties?
PRIMARY AND SECONDARY PUNISHERS
Punishers can be categorized into two
groups:
 Primary Punisher
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A
stimulus that in inherently punishing; an
example is electric shock.
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Secondary Punishers
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A stimulus that has acquired punishing
properties through association with other
punishers.
Positive Reinforcement:
Good Grades
Behavior:
Studying
Negative
Reinforcement:
Poor Grades
Result:
Studying
Increases
Behavior:
Studying
Negative
Punishment:
Loss of Time
with Friends
Positive Punishment:
Ridicule by
Friends
Result:
Studying
Decreases
Putting It All Together
Positive
Punishment
Positive
Reinforcement
Negative
Punishment
Negative
Reinforcement
http://www.youtube.com/watch?v=OxdtMVww2q0&safety_mode=true&persist_s
afety_mode=1&safe=active
PRINCIPLES OF OPERANT CONDITIONING
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Early in his career Skinner (1938) used the Skinner
Box to demonstrate the principles of operant
conditioning.
A rat that had previous learned to eat from the foodreleasing device was placed in the box
Because there was no food present in the box, the rat
began to engage in typical rat-like behaviors. (sniffing,
random touching, scurrying etc.)
Once he hit the lever that released food, he continued
to display that behavior
THE SKINNER BOX
SCHEDULES OF REINFORCEMENT
Timing and Frequency are very important
 Continuous Reinforcement
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Reinforcement Schedule in which a particular
response is always reinforced after every
occurrence of the target behavior.
Partial Reinforcement
 Target
behaviors are only reinforced sometimes.
 Which
do you think lasts longer and is more stable?
Why?
SCHEDULES OF REINFORCEMENT
Partial
SCHEDULES OF REINFORCEMENT
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Fixed and Variable Ratio
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Fixed and Variable Interval
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Rely on Responses
Rely on Time
Ratio schedules produce
higher response rates than
Interval schedules
SCHEDULES OF REINFORCEMENT
Fig 6.9
REINFORCEMENT SCHEDULES AND EXTINCTION
Extinction will occur if reinforcement is removed
SCHEDULE EXAMPLES
Variable
schedules
Fixed
schedules
Ratio
Interval
Paid for every 10 pizzas
Cramming for an exam
Ejected from a basketball game
after five fouls
Picking up check
Playing at a slot machine
Pop quiz in class
Sales commissions
Teacher checks work
periodically when you
are working in groups
SHAPING
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Shaping
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An operant conditioning procedure in which
successive approximations of a desired response
are reinforced.
Successive Approximations
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Behaviors that are ordered in terms of increasing
similarity or closeness to the desired response.
http://www.youtube.com/watch?v=Q2v3Q0osmoE&s
afety_mode=true&persist_safety_mode=1&safe=a
ctive
CHAINING
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Chaining
An operant conditioning procedure in which
learned reactions follow one another, and each
reaction is the signal for the next
 Chains of responses are response patterns
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Example:
 Swimming
various strokes: Arm chain, Breathing
chain, leg chain
BIOLOGICAL LIMITS ON LEARNING
All principles of operant and classical
conditioning are limited by an animal's genetic
disposition and physical characteristics.
 A fish cannot be trained to climb a ladder.
 http://drsophiayin.com/blog/entry/animalbehavior-enterprises-creates-the-field-ofapplied-animal-psychology
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SKINNER: THE MAN AND THE MYTH
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Because of his groundbreaking work B. F. Skinner is often
called the greatest American Psychologist.
Believed that we could study private emotions and thought by
observing our own sensory responses, the verbal reports of
others, and the conditions under which such events occur.
Thoughts cannot explain behavior ~ there are only behaviors
that occur because of reinforcement and punishment.
SKINNER: THE MAN AND THE MYTH
The environment should be
manipulated to alter behavior.
 Controversial experiments like
his “air-crib” or “living space”
attempted to control environmental
discomfort and reduce the a baby’s
distress. The experiment was
misunderstood and criticized as
cold-blooded at the time.
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REINFORCERS VERSUS
REWARDS AND PUNISHMENT
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Reinforcers are known by their effect (increase
response)
Rewards are pleasant events that affect behavior
Punishment are aversive events that decrease the
frequency of the behavior they follow
NEGATIVE REINFORCERS VERSUS PUNISHMENT
TWO USES OF NEGATIVE REINFORCEMENT
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Escape Conditioning:
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Avoidance Conditioning:
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A person’s behavior causes an unpleasant event to
stop. This increases behavior.
The person’s behavior prevents an unpleasant
situation from happening. This increases behavior.
Examples:
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A child whining and crying to get what he wants when
a parent has said “No”
Repeating “I’ll do it later,” or “Okay,” when asked to
complete a chore, and you never do it
PUNISHMENT
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An unpleasant consequence occurs and
DECREASES the behavior
Examples?
WHEN PUNISHMENT WORKS
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Punishment can be a deterrent for some young
criminal from repeated offenses (Brennan &
Sarnoff, 1994) provided the punishment is
consistently applied.
The severity of the punishment, however, made
no difference in term of relapsing into a
previous undesirable type of behavior.
Inconsistent punishment was found to have the
same effect as an intermittent reinforcement
schedule making the poor behavior highly
resistive to extinction.
WHEN PUNISHMENT FAILS
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People often administer punishment inappropriately
or mindlessly.
The recipient of punishment often responds with
anxiety, fear, or rage.
The effectiveness of punishment is often temporary,
depending heavily on the presence of the punishing
person or circumstances.
Person learns to avoid the person giving the
punishment
WHEN PUNISHMENT FAILS
Most misbehavior is hard to punish
immediately.
 Punishment conveys little information.
 An action intended to punish may instead be
reinforcing if brings attention.
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