Learning

Instrumental Conditioning & Observational Learning

 

"He who learns and runs away will live to learn another day."

E. L. Thorndike

Important Announcement!

• The second thought paper is due on October 18th.

Brief Review

• Learning: Change in behavior, thoughts, or feelings of an organism that results from experience.
• Classical conditioning: The principal way that organisms learn the meaningful relations between events.

Instrumental Conditioning

• Organisms learn how their own behaviors can produce outcomes; they learn that their own behavior is instrumental in producing rewards or penalties.

Thorndike's Law of Effect

• If a response in a particular situation is followed by a satisfying or pleasant outcome, the response will be strengthened.
• If a response in a particular situation is followed by an unsatisfying or unpleasant outcome, the response will be weakened.

Thorndike's Law of Effect

• Key words: "particular situation," "satisfying or pleasant," "strengthened."
• Learning is situation dependent.
• Strengthened = Response is more likely to occur in the future in that situation; weakened = response is less likely to occur in the future in that situation.
• What is "pleasant" or "satisfying?"

Reinforcement

• Reinforcer: A stimulus that increases the likelihood that the behavior associated with it will happen again.

Two major types of reinforcement:

• Positive reinforcement: Presentation of a stimulus after a response increases the likelihood of the response.
• Negative reinforcement: Removal or cessation of an unpleasant stimulus after a response increases the likelihood of the response. NOT the same as punishment.

Examples of Positive Reinforcement

 

What Makes a Stimulus a Reinforcer?

• "Bliss point"
• Response deprivation theory of reinforcement

Schedules of Reinforcement

• Continuous: Behavior is reinforced every time it is produced.
• Partial: Behavior is reinforced some of the time, but not always.
• Partial reinforcement produces greater resistance to extinction.

Types of Partial Reinforcement

• Fixed-ratio, variable-ratio, fixed-interval, and variable-interval.
• Affects type of responding & resistance to extinction.

Shaping: Getting the Organism to Behave in the Desired Manner

• Reinforcement is delivered for successive approximations to the desired response.
• Let's try it . . .

Problems with Reward

• Extrinsic vs. intrinsic reinforcers
• Extrinsic: Not inherently related to the activity being reinforced (e.g., praise, money, prizes).
• Intrinsic: Inherently related to the activity being reinforced (e.g., enjoyment, self-satisfaction).
• Excessive extrinsic reinforcement can reduce intrinsic motivation.

Lepper, Greene, & Nisbett

Why?

• Payment = work.
• Extrinsic reinforcers are perceived as "controlling."
• "Bliss point."
• Implications: Grades, allowance.

Punishment

• Stimulus that decreases the probability of a response, either through the application of an unpleasant stimulus ("positive") or the removal of a pleasant one ("negative").
• Usually less effective than reinforcement.
• May lead to unintended consequences:

Unintended Consequences of Punishment

• Punishment can increase the likelihood of aggressive behavior.
• Punishment may cause injury.
• May cause fear of the punisher or the context (what's the mechanism?).

Effective Punishment

• "When you take a knife away from a child, give him a piece of wood instead."
• Combine with reinforcement of desired behavior.
• Make sure individual understands why the behavior is being punished.
• Implement punishment immediately.

Effective Punishment

• Administer punishment that is sufficiently intense to stop the behavior, but no more.
• Make punishment consistent and inescapable.
• Use penalties, i.e., the removal of pleasant stimuli (negative punishment), rather than physical or emotional pain (positive punishment).

Observational (Social) Learning

• We learn by observing the behavior of others.

Importance of Observational Learning

• Gender identification and gender-role development.
• Television violence.

Albert Bandura's Experiments

• Pre-school children watched a film showing an adult who punched, kicked, and hit with a hammer a Bobo doll. The film ended with the adult being rewarded, punished, or neither.
• Children were then allowed to play with the Bobo doll. Children who saw adult rewarded were more likely to behave aggressively; children who saw adult punished were less likely to behave aggressively.

APA Commission Findings

• Higher levels of viewing violence on TV are correlated with increased acceptance of aggressive attitudes and increased aggressive behavior.
• Strength of relation is about the same as between smoking and lung cancer.

Summary

• Instrumental conditioning is the way that organisms learn how their own behaviors can produce outcomes.
• Behaviors become more or less likely to occur depending on their outcomes.
• Reinforcement makes behaviors more likely; punishment makes them less likely.
• Pattern and persistence of responding depend in part on the schedule of reinforcement.
• Not all learning requires direct reinforcement; we learn by observing the behavior of others.