REINFORCEMENTPsych of Learning

E. L. THORNDIKE

Famous for “puzzle box” experiments of animal learning.

Examined animal intelligence by testing animal learning (change in behavior).

Plotted animals learning on graphs (perhaps first learning curves), see p. 122.

Used the “discrete trial procedure.”

LAW OF EFFECT Relationship between behavior and its consequences.

Behavior has two kinds of consequences: Satisfying state of affairs Annoying state of affairs

Satisfying consequences (or effects) will result in greater likelihood that the behavior will be repeated.

Believed animals learned by “trial and success.”

“Hedonism,” the tendency to seek out pleasure and avoid pain, had long been debated by philosophers.

B. F. SKINNER

Invented Skinner box (AKA operant chamber, experimental chamber).

The Behavior of Organisms (1938) Numerous contributions to psychology:

Changes in behavior rate a measure of learning. ABA research design. Coined precise language for the study of animal learning.

Many awards, but also many critics. Won APA’s 1st special citation for a lifetime of

outstanding contributions. Used the “free operant procedure.”

OPERANT (INSTRUMENTAL) CONDITIONING AKA operant learning or instrumental

learning. “Experiences whereby behavior is

strengthened or weakened by its consequences…” (p. 124).

Emphasis on behavior producing consequences.

The learning is “necessarily active” (p. 125).

Individual must act. Action Consequence Action (or

Inaction)

TYPES OF OPERANT LEARNING

Positive Reinforcement

PositivePunishment

Negative Reinforcement

NegativePunishment

Strength of BehaviorIncreases

Decreases

Conse

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Rem

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REINFORCEMENT

Increase in the strength of behavior due to its consequences.

3 Characteristics of Reinforcement (Charles Cantania, 1998): A behavior must have a consequence. The behavior must increase in strength. The increase in strength must be the result

of the consequence.

2 KINDS OF REINFORCEMENT

Positive Reinforcement Negative Reinforcement

•Behavior is strengthened by the appearance a stimulus or increase in intensity of a stimulus (or a positive reinforcer).

•AKA “reward learning” but not always things we want.

•Positive reinforcer (or stimulus) is usually sought out by the organism.

•A positive reinforcer strengthens the behavior that precedes it.

•Behavior is strengthened by the REMOVAL or DECREASE in intensity of a stimulus.

•Stimulus is a negative reinforcer (usually something that we want to avoid).

•Behavior is reinforced by escaping from an aversive stimulus. AKA “escape-avoidance learning.”

OPERANT VS. CLASSICAL CONDITIONINGOperant Conditioning Classical Conditioning

•Subject must actively DO something.

•Three – term contingency: A. Initial situation B. Behavior in that situation C. Consequences of the behavior.

•Stimulus is contingent on behavior.

•Often occurs with classical conditioning.

•Subject is relatively passive. Two stimuli occur regardless of subject’s behavior.

•“S – S” learning or the pairing of 2 stimuli.

•Stimulus (US) is contingent on another stimulus (CS).

•Often occurs with operant conditioning.

KINDS OF REINFORCERSPrimary Reinforcers Secondary Reinforcers

•Not dependent on association with other reinforcers.

•Very few primary reinforcers.

•Lose effects quickly, known as satiation.

•Examples: food, water, maintaining body temperature, social contact, information

•Dependent on association with other reinforcers, often with a primary reinforcer (e.g. money is a secondary reinforcer because of the things it buys us, may of which are primary reinforcers).

•AKA “conditioned reinforcers.”

•More enduring; satiate more slowly than primary reinforcers.

•Must be paired with another reinforcer at least some of the time.

•Can provide immediate reinforcement that is not disruptive and that can be used in many different places.

CONTRIVED VS. NATURAL REINFORCERS Contrived reinforcers

Have been arranged or created by someone.

Natural reinforcers Occur naturally.