Operant Conditioning

Mr. KochAP Psychology

Forest Lake High School

Operant Conditioning

• Type of learning in which behavior is strengthened if followed by reinforcement or diminished if followed by punishment

– (aka - Instrumental Conditioning)

• Antecedent → Behavior → Consequence (stimulus) (response)

– Law of Effect (Thorndike)• Principle that behaviors followed by:

– Favorable consequences → more likely– Unfavorable consequences → less likely

B.F. Skinner

(1904-1990)

Skinner Box(aka Operant Chamber)

• Controlled environment with a bar or key for animal to manipulate to obtain food/water reinforcer

• Contains devices to record responses

Operant Conditioning• Reinforcement– Any event that strengthens the behavior it follows

• Positive Reinforcement– Increases frequency of behavior by adding a pleasant stimulus

• Ex: Money, praise, prizes, attention

• Negative Reinforcement– Increases frequency of behavior by removing an unpleasant

(aversive) stimulus• Ex: Aspirin, giving in to tantrum, faking sick, drugs to avoid withdrawal

Operant Conditioning

• Primary Reinforcer– Innately reinforcing stimulus (satisfies a biological

need)• Ex: food, water, relief from pain, etc.

• Secondary Reinforcer (aka - Conditioned Reinforcer)

– Gains its reinforcing power through its association with a primary reinforcer• Ex: money, grades, etc.

Operant Conditioning• Shaping– Reinforcing a series of behaviors which

progressively become more specific and similar to desired response • (guide toward closer approximations of desired goal)

• Note:– What is reinforcing to one may not be to another• Depends upon perspective of learner

– Ex: suspension; forced to stay after school

Schedules of Reinforcement

• Continuous Reinforcement– Reinforcing desired response every time it occurs• + acquire quickly• - extinct quickly

• Partial (intermittent) Reinforcement– Reinforcing part of the time• - acquire slower• + extinct slower

Schedules of Reinforcement(Partial Reinforcement)

• Fixed-Ratio schedule– Reinforced after certain number of responses

– Ex: piecework, bonus paid for selling certain # items

• Variable-Ratio schedule– Reinforcement after an unpredictable number of responses• Very hard to extinguish

– Ex: gambling, fishing, hitchhiking

Schedules of Reinforcement(Partial Reinforcement)

• Fixed-Interval schedule– Reinforce a response after a set period of time has elapsed• Ex: payday, mail delivery, school schedule

• Variable-Interval schedule– Reinforce a response at unpredictable time intervals• Ex: pop quiz, random drug tests, waiting for taxi

Punishment• An event that decreases the strength of a

behavior it follows• Aversive Conditioning – using punishment to teach

• Positive Punishment (“Type I” Punishment)

– Adding an unpleasant (aversive) stimulus to decrease behavior• Ex: spanking, electric shock

• Negative Punishment (“Type II” Punishment)

– Removing a pleasant/desirable stimulus to decrease behavior• Ex: time out, grounding

Punishment

• Problems with punishment:– Tells us what not to do, not what to do– May teach avoidance, fear, or aggression– If punishment is unpredictable, unavoidable – get

sense it is beyond our control• May lead to depression, helplessness

– Better to emphasize reinforcement

Operant Conditioning

• Avoidance Conditioning– Undesirable behavior not yet

present• subject taught to avoid stimulus

• Counter-conditioning– Undesirable behaviors already

learned• Seek a new response – unlearn old

behavior