Operant Conditioning

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Chapter 6
Definition
 Learning a behavior is strengthened if followed by
reinforcement or diminished if followed by
punishment
 Classical conditioning involves respondent
behavior that occurs as an automatic response to
some stimulus.
 Operant conditioning involves operant behavior, a
behavior that operates on the environment
producing rewarding or punishing stimuli
Operant Conditioning
Law of Effect
 Edward L. Thorndike
 behaviors followed by
favorable consequences
become more likely
 behaviors followed by
unfavorable
consequences become
less likely
Early Operant Conditioning
 Thorndike’s Box used on cats
First Trial
in Box
Scratch at bars
After Many
Trials in Box
Push at ceiling
Situation:
stimuli
inside of
puzzle box
Dig at floor
Howl
Etc.
Scratch at bars
Push at ceiling
Situation:
stimuli
inside of
puzzle box
Dig at floor
Howl
Etc.
Etc.
Etc.
Press lever
Press lever
B.F. Skinner
 Using Thorndike's law
of effect as a starting
point Skinner
developed the Operant
chamber or the Skinner
box to study operant
conditioning.
 Operant chamber or
Skinner box comes with
a bar or key that an
animal manipulates to
obtain a food or water
reinforcer
 It is connected to
devices that record the
animal’s responses.
B.F. Skinner
 Shaping: Reinforcing
small steps toward more
complex behavior
 Discriminative Stimulus:
signals availability of
reinforcement or
punishment (light, sound,
parent)
Skinner Box
Extending Skinner’s Understanding
Cognition and Operant Conditioning
 Intrinsic Motivation
 Internal
 behavior for its own sake
 Extrinsic Motivation
 External
 The desire to perform a
behavior due to promised
rewards or threats of
punishments
Extending Skinner’s Understanding
Biological Predispositions
 Biological constraints predispose
organisms to learn associations that
are naturally adaptive
Skinner’s Legacy
Applications of Operant Conditioning
 At school
 Grades, college, graduation
 In sports
 Winning, skill development, belonging
 At home
 Love, money, belonging
 For self-improvement
Discussion
 What are the similarities between
classical and operant conditioning?
 What are the differences between
classical and operant conditioning?
Operant vs. Classical
Conditioning
Processes in Operant Conditioning
w Acquisition: Initial stages of learning through
reinforcement
w Extinction: The gradual weakening and
disappearance of a response tendency because the
response is no longer followed by a reinforcer
w Generalization: When responding increases in the
presence of new stimuli that resembles the original
discriminative stimulus
w Discrimination: When responding does not increase
in the presence of a new stimulus that resembles the
original discriminative stimulus
Reinforcement: consequences
that strengthen responses
 Positive Reinforcement: A response is
strengthened because it is followed by the
presentation of a rewarding stimulus
 Negative Reinforcement: A response is
strengthened because it is followed by the removal
of an aversive stimulus (buzzer for seat belt)
 Conditioned Reinforcement
 Primary Reinforcers: Inherently reinforcing
satisfy biological needs (food, water, shelter)
 Secondary Reinforcers: Acquire reinforcing
qualities by being associated with primary
reinforcers (money, stickers, praise)
Exchanging reinforcers
 Tokens Systems
 Given tokens for
good behavior or
compliance with
those in charge
 Exchanged for
Primary reinforcers
Schedules of Reinforcement
 Continuous: Reinforce
every time
 fastest, but quickest to
extinction)
 ATM
 Grades for completing
assignments
Fixed Ratio (FR)
 Fixed Ratio: Reinforcer is
given after a fixed number of
non-reinforced responses


reinforces a response only after a
specified number of responses
faster you respond the more
rewards you get
 Very high rate of responding
 Commission Pay
 Getting a bonus for every 5 cars
sold.
Fixed Interval (FI)
 Fixed Interval: Reinforcer is
given for the first response
that occurs after a fixed
time interval has elapsed

reinforces a response only
after a specified time has
elapsed
 response occurs more
frequently as the anticipated
time for reward draws near
 Paycheck every Friday
Variable Ratio (VR)
 Variable Ratio:
Reinforcer after a
variable number of
non-reinforced
responses
 very hard to extinguish
because of
unpredictability
 like gambling, fishing
 Bingo
Variable Interval (VI)
 Variable Interval:
Reinforcer is given for the
first response after a
variable time interval
has elapsed
 reinforces a response at
unpredictable time
intervals
 produces slow steady
responding
 Pop quiz
Schedules of
Reinforcement
Punishment
Although there
may be some
justification for
occasional
punishment
(Larzelaere &
Baumrind, 2002), it
usually leads to
negative effects.
1. Punishment can result in
unwanted fears.
2. Conveys no information to
the organism.
3. Justifies pain to others.
4. Unwanted behaviors
reappear in its absence.
5. Aggression towards the
agent.
6. One unwanted behavior
appears in place of another.
Punishment
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