Download Operant Conditioning

Unit 6 (Mod 27):
Operant Conditioning
A.P. Psychology
Classical Vs. Operant Conditioning

Classical Conditioning
forms associations between stimuli (CS and US)


Respondent Behavior
Operant conditioning forms
an association between
behaviors and the resulting
events.

Operant Behavior
Operant Conditioning

Operant Conditioning:

A type of learning in which behavior is strengthened if
followed by a reinforcer or diminished by a punisher
Skinner’s Experiments

B.F. Skinner’s experiments extend Edward
Thorndike’s law of effect.

Thorndike’s law of effect-states that rewarded behavior is
likely to occur again & behaviors that are followed by
undesirable consequences will happen less often.
Skinner’s Experiments

Operant Chamber
Chamber that contained a bar/key that an animal can
manipulate to obtain a food/water reinforce
 The bar or key is connected to devices that record the
animal’s response.


Also known as a “Skinner Box”
Shaping

Shaping

The operant conditioning procedure in which reinforcers guide
behavior towards the desired target behavior through successive
approximations.
A rat shaped to sniff mines. A manatee shaped to
discriminate objects of different shapes, colors and sizes.
Reinforcement

Reinforcement (reinforcers):
Any event that strengthens (reinforces) the behavior it follows
 A reinforcement is a reward

Types of Reinforcers
Types of Reinforcers

Primary Reinforcer:

An innately reinforcing stimulus

Often satisfies a biological need


E.g. Pizza
Conditioned Reinforcer:
A stimulus that gains its reinforcing power through its
association with a primary reinforce
 Also known as a secondary reinforcer


E.g. Money
Types of Reinforcers

Immediate Reinforcer:


Behavior results in instantaneous reward
Delayed Reinforcer:
Behavior is not rewarded immediately
 In lab experiments, rats do not respond to reinforcers that
are delayed more than 30 seconds
 Humans DO respond to delayed reinforcers: weekly
paychecks, end of term grades, etc.

Schedules of Reinforcement

Reinforcement schedule


Continuous reinforcement:


Pattern that defines how often a desired response will be
reinforced
Reinforcement occurs after EVERY desired response
Partial reinforcement:

Reinforcement occurs only part of the time
Acquisition is slower
 Greater resistance to extinction

Schedules of Reinforcement

Fixed-Ratio:

Reinforces a response only after a specified number of
responses


E.g. Buy 10 coffees, get one free
Variable-Ratio:

Reinforces response after an unpredictable number of
responses

E.g. Slot machines
Schedules of Reinforcement

Fixed-Interval:

Reinforces a response only after a specified time has
elapsed


E.g. Checking your mailbox more frequently the closer it gets to its’ normal
delivery time
Variable-Interval:

Reinforces a response at unpredictable time intervals

E.g. checking text messages frequently when waiting for a text, although no
designated time for said text has been established
Schedules of Reinforcement
Schedules of Reinforcement
Schedules of Reinforcement
Schedules of Reinforcement
Schedules of Reinforcement
Schedules of Reinforcement

Reinforcement linked to a number of responses (a ratio schedule)
produces a higher response rate than reinforcement linked to
amount of time elapsed (an interval schedule)
Schedules of Reinforcement


Reinforcement linked to a number of responses (a ratio schedule)
produces a higher response rate than reinforcement linked to
amount of time elapsed (an interval schedule)
Predictability is important too: unpredictable (variable) schedules
produced more consistent responses than predictable (fixed) schedules.
Punishment

An event that tends to (or is meant to) decrease the
behavior that precedes it.

1.
Studies of punishment have revealed a few important points:
Punished behavior is suppressed, not erased.

2.
Punishment teaches discrimination among situations.

3.
The spanking likely doesn’t prevent the child from swearing, but it
might stop him/her from swearing around his/he parents
Punishment can teach fear.

4.
It’s a temporary, negative reinforcement of the punishment
Child might associate fear not just with the swearing that causes the
punishment, but also with the punisher or place of punishment
Physical punishment may increase aggression.

Physical punishment may model aggression as a way to cope with
problems
Punishment
Punishment
Punishment