October 23

ThorndikeSkinner

ReinforcementCognition and Learning

Reading/Class Quiz: Thursday, read/review p. 247-256

Optional Experiment, due Friday

B.F. Skinner

Operant chamber (Skinner Box)

Operant chamber (Skinner Box)

A pigeon turning

• SHAPING—an operant conditioning procedure in which successive approximations of a desired outcome are reinforced

• SUCCESSIVE APPROXIMATIONS—behaviors that are ordered in terms of increasing similarity or closeness to the desired outcome

Reinforcers: Immediate vs. Delayed?

Immediate vs. Delayed

Immediate Reinforcers vs. Delayed Reinforcers: Walter

Mischel developed the "Marshmallow Test" in the late 1960's and found children who are able to delay gratification

tend to become socially competent and high-achieving

adults (1989).

Reinforcement Schedules

Types of Reinforcement

• CONTINUOUS

• INTERMITTENT– Fixed ratio– Variable ratio– Fixed interval– Variable interval

Reinforcement

• CONTINUOUS—a reinforcer for each and every correct response/behavior

• INTERMITTENT– Fixed ratio– Variable ratio– Fixed interval– Variable interval

Types of Reinforcement

• CONTINUOUS—a reinforcer for each and every correct response/behavior

• INTERMITTENT (Partial)—the tendency for a response that is reinforced after some, but not all, correct responses– Fixed ratio– Variable ratio– Fixed interval– Variable interval

• INTERMITTENT (Partial)—the tendency for a response that is reinforced after some, but not all, correct responses

– Fixed ratio—schedule of reinforcement in which the NUMBER OF RESPONSES required for reinforcement is ALWAYS THE SAME

– Variable ratio– Fixed interval– Variable interval

• INTERMITTENT (Partial)—the tendency for a response that is reinforced after some, but not all, correct responses

– Fixed ratio—schedule of reinforcement in which the NUMBER OF RESPONSES required for reinforcement is ALWAYS THE SAME

– Variable ratio—schedule of reinforcement in which the NUMBER OF RESPONSES required for reinforcement is DIFFERENT for each trial or event

– Fixed interval– Variable interval

• INTERMITTENT (Partial)—the tendency for a response that is reinforced after some, but not all, correct responses– Fixed ratio—schedule of reinforcement in which the NUMBER OF

RESPONSES required for reinforcement is ALWAYS THE SAME– Variable ratio—schedule of reinforcement in which the NUMBER OF

RESPONSES required for reinforcement is DIFFERENT for each trial or event

– Fixed interval—schedule of reinforcement in which the interval of time that must pass before reinforcement becomes possible is always the same

– Variable interval

• INTERMITTENT (Partial)—the tendency for a response that is reinforced after some, but not all, correct responses

– Fixed ratio—schedule of reinforcement in which the NUMBER OF RESPONSES required for reinforcement is ALWAYS THE SAME

– Variable ratio—schedule of reinforcement in which the NUMBER OF RESPONSES required for reinforcement is DIFFERENT for each trial or event

– Fixed interval—schedule of reinforcement in which the interval of time that must pass before reinforcement becomes possible is always the same

– Variable interval—schedule of reinforcement in which the interval of time that must pass before reinforcement becomes possible is different for each trial or event