Reinforcement: Beyond Habit

What Is Shaping?

What Is Shaping?

• Shaping: Reinforcing successive approximations of a desired behavior.

• Successive approximations: Small steps toward the target behavior.

• Purpose: Teach new behaviors that rarely or never occur naturally.

• Key rule: Reinforce closer approximations; stop reinforcing earlier ones.

Examples of Shaping

• Rat: Looks at lever → approaches → touches → presses.

• Pigeon (Skinner): Reinforced for gradually turning in a complete circle.

• Child (Skinner): Small arm movements → larger movements → turning on a light.

• Student: Rough letters → clearer letters.

• Rehabilitation: Easy tasks → gradually harder tasks.

• Thorndike: Failed to train a dog because he did not systematically reinforce small steps.

Shaping vs. Natural Selection

Natural Selection

• Natural shaping: Behavior changes gradually through reinforcement without planned training.

• Tantrums: Parent gives in to louder crying → reinforces increasingly severe tantrums.

• Otters: Parents gradually provide more challenging prey.

• Meerkats: Adults give pups increasingly difficult prey as they improve.

Shaping vs. Natural Selection

• Shaping: Reinforcement selects behaviors.

• Natural selection: Environment selects inherited traits that improve survival/reproduction.

• Similarity: Both involve variation and selection.

• Key principle: New forms develop from existing forms.

What Is Chaining?

What Is Chaining?

• Behavior chain: Series of connected behaviors performed in a specific order.

• Chaining: Teaching a behavior chain by reinforcing its individual steps.

• Task analysis: Breaking a complex behavior into smaller steps (links).

• Examples: Brushing teeth, cooking, getting dressed, gymnastics routines.

• Skinner (1938): Trained a rat to perform a chain of behaviors.

Two Types of Chaining

Two Types of Chaining

Forward Chaining

• Teach the first step first.

• Gradually add steps in order.

• Example: A → AB → ABC → ABCD.

Backward Chaining

• Teach the last step first.

• Gradually add earlier steps.

• Example: D → CD → BCD → ABCD.

• Often more efficient than forward chaining.

Reinforcement in Chaining

Reinforcement in Chaining

• Each step is reinforced by the opportunity to perform the next step.

• Conditioned reinforcers: Often maintain intermediate steps.

• Primary reinforcers: Often occur at the end (e.g., food).

• Final reinforcement is essential: Without it, the chain may break down.

Shaping vs. Chaining

Shaping vs. Chaining

• Shaping: Reinforces gradual improvements in a behavior.

• Chaining: Connects separate behaviors into a sequence.

• Connection: Shaping can teach individual steps needed for chaining.

• Both: Can occur naturally or through planned training.

Problems & Insight

Problems & Insight

• Problem: Reinforcement is possible, but the behavior needed to obtain it is missing.

• Insight: A sudden solution that appears without trial and error.

• Bruner (1983): Suggested insight occurs without learning.

• Main idea: Apparent insight often results from past learning and reinforcement.

Reinforcing Creativity

Reinforcing Creativity

• Karen Pryor (1969): Reinforced new tricks in dolphins.

• Malia (dolphin): Learned to perform new behaviors for rewards.

• Hou (dolphin): Produced more new tricks when novelty was reinforced.

• Pigeons: Developed unusual behaviors when originality was rewarded.

Creativity in Humans

Creativity in Humans

• Glover & Gary (1976): Rewarding unusual ideas increased students' creativity.

• Chambers (1977): Praising new block designs doubled children's creative output.

• Main finding: Reinforcing originality increases creativity.

Do Rewards Reduce Creativity?

Do Rewards Reduce Creativity?

• Promised rewards: Can reduce creativity.

• Rewards for conventional behavior: Increase conventional behavior.

• Rewards for creative behavior: Increase creativity.

• Key factor: What behavior is reinforced, not simply whether rewards are given.

• Example: Rewarding original drawings increases originality.

What Is Superstitious Behavior?

What Is Superstitious Behavior?

• Superstition: Repeating behavior that does NOT actually cause reinforcement.

• Coincidental reinforcement: Reward occurs by chance after a behavior.

• Key idea: Accidental rewards can strengthen unrelated behaviors.

Superstition in Humans

Superstition in Humans

• Wagner & Morris (1987): Children developed superstitions when a clown gave marbles at fixed intervals.

• Ono (1987): Students developed superstitions when points appeared regardless of behavior.

• Examples: Lucky charms, rituals, repeated movements.

Limitations of Skinner's Theory

Limitations of Skinner's Theory

• Coincidental reinforcement explains some superstitions, NOT all.

• Staddon & Simmelhag (1971): Failed to reproduce Skinner's pigeon results.

• Some superstitions are taught or learned from others.

• Complex, lasting superstitions may require other explanations.

Learned Helplessness

Learned Helplessness

• Learned helplessness: Giving up after learning that efforts don't change outcomes.

• Cause: Repeated exposure to uncontrollable negative events.

• Key idea: Animals learn that their actions have no effect.

Seligman's Dog Experiment (1967)

Seligman's Dog Experiment (1967)

• Seligman & Maier: Studied dogs exposed to unavoidable shocks.

• Normal dogs: Quickly learned to escape shocks.

• Previously shocked dogs: Stopped trying to escape, even when escape was possible.

• Finding: Inability to control shocks caused learned helplessness.

• Important: Uncontrollable shocks, NOT shocks alone, cause helplessness.

Preventing Learned Helplessness

Preventing Learned Helplessness

• Immunization: Previous experience controlling or escaping shocks prevents helplessness.

• Seligman & Maier: Dogs trained to escape shocks resisted helplessness.

• Volpicelli: Rats with prior escape experience kept trying, even when escape became impossible.

Learned Industriousness

Learned Industriousness

• Learned industriousness (Eisenberger): Learning to persist through difficult tasks.

• Cause: Reinforcing effort and persistence.

• Effect: People work harder and give up less easily.

• Opposite: Learned helplessness.