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B.F. Skinner and Operant Conditioning

• Classical conditioning involves an automatic response to a stimulus

• Operant conditioning involves learning how to control one’s response to elicit a reward or avoid a punishment

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The “Skinner Box”: Skinner’s Hypothesis, Methodology, and

Results• Rats placed in

“Skinner boxes” • Shaped to get closer

and closer to the bar in order to receive food

• Eventually required to press the bar to receive food

• Food is a reinforcer

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Basic Types of Reinforcement

Reinforcer: any event that increases or strengthens a behavior it follows.

Primary Reinforcer: innately satisfying (not learned, i.e. food)

Secondary (conditioned) Reinforcer: power through association with primary reinforcers (learned, i.e. good grades)

Positive Reinforcement: strengthens a response by presenting a stimulus after a response (Praise, money)

Pass Out Handout!

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Negative Reinforcement and Punishment

Negative reinforcement: Removing an unpleasant stimulus

Punishment

1. Unpleasant stimulus

2. Removal of unpleasant stimulus

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1. Introducing an unpleasant stimulus

2. Withholding a pleasant stimulus

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Law of Effect-Thorndike

• Reinforced behaviors are strengthened

• Punished behaviors are decreased

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Rates and Types of Reinforcement:

Additional ExperimentsFixed-ratio: after a fixed number of responses reinforcement is given. (sales) Produces high response rate

Variable-ratio: after an unpredictable number of responses reinforcement is given (gambling) Produces high response rate

Fixed-interval: after a fixed amount of time reinforcement is given. (mail)

Variable-interval: after an unpredictable amount of time reinforcement is given (email)

Predictability Matters

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Skinner’s ImportanceEducation: programmed instruction

Work

Parenting Personal goals

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Albert Bandura: Hypothesis

• Believed we learn through observation and imitation• Hypothesized that children would imitate aggressive

behavior they observed

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Bandura’s Methodology

• Children watched films of adults beating Bobo dolls

• Three groups: aggression-rewarded, aggression-punished, no consequences

• Children went into rooms with toys that they were told not to play with

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Bandura’s Results

• Children in the aggression-punished group expressed the fewest aggressive behaviors toward the Bobo dolls

• Children in the other two groups expressed an equal number of aggressive behaviors and were more aggressive than children in the aggression-punished group

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MODELREWARDED

MODELPUNISHED

NOCONSEQUENCES

GIRLSBOYS

EFFECT OF OBSERVED CONSEQUENCE ON IMITATIVE BEHAVIOR

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Bandura’s Experiment, continued

• Children promised rewards for imitating the adult in the film

• Now, all three groups were equally aggressive

• Children had learned the aggressive behavior from the film, but those who saw the adults being punished were less likely to act aggressively

Viewing aggressive behavior Rewards for imitation Aggressive behavior

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Bandura’s Social Learning Theory

• Relates to effects of violence and other images on TV and in the movies

• Children imitate good and neutral behaviors as well as bad ones