Operant Conditioning A form of learning in which a specific action (an operant response) is made to occur either more frequently or less frequently by manipulating its consequences in the environment. B.F. Skinner Operant Response Change in Environment Change in response Gets food Dog stands again Dog stands An operant response “operates” on the environment and causes it to change in some way. The environment, in turn, causes the behavior to change in some way.

Operant Conditioning Versus Classical Conditioning In Classical Conditioning, the subject’s response has no consequences; it produces no change in the environment. The dog gets the food after the bell is rung whether or not he salivates to the bell. His behavior doesn’t matter. In Operant Conditioning, the dog has to stand up to get the food. His behavior does matter.

In other words, in Pavlov’s experiment, the food is not a reward for responding to the bell because it is given no matter what the dog does. In the Operant Conditioning example, the food is a reward because it depends on the dog’s behavior—he has to stand up. Operant Conditioning works on the Law of Effect: behavior changes according to its consequences. The Law of Effect does not apply to Classical Conditioning. Reflexes are not sensitive to their consequences.

A B C Antecedents Behavior Consequences Analyzing Behavior The ‘s of Operant Conditioning Antecedents Behavior Consequences 1. Discriminative Stimulus (SD) Operant Response 1. Reinforcers 2. Punishers 2. Delta Stimulus (S )

A B C Operant Conditioning Chamber (“Skinner Box”) Analyzing Behavior The A B C ‘s of Operant Conditioning Operant Conditioning Chamber (“Skinner Box”)

A B C Behavior Analyzing Behavior The ‘s of Operant Conditioning Operant Response: a set of actions that all have the same effect on the environment. For example, in an operant conditioning chamber (“Skinner Box”), the response is defined as a “bar press”. The bar has to go down a certain distance. It doesn’t matter which paw the rat uses.

A B C Consequences Analyzing Behavior The ‘s of Operant Conditioning Reinforcer: a stimulus that follows a response and results in an increase in the chances that the response will be repeated. For example, after the rat presses the bar, a food pellet (stimulus) is presented. The rat is then more likely to press the bar again (compared to a condition where bar pressing produced no food).

A B C Consequences Analyzing Behavior The ‘s of Operant Conditioning Punisher: a stimulus that follows a response and results in a decrease in the chances that the response will be repeated. For example, every time the rat presses the bar for food, he receives an electric shock. He will probably keep pressing but with longer delays between bar presses.

A B C Consequences Answer: the scoldings are a reinforcer. Analyzing Behavior The A B C ‘s of Operant Conditioning Consequences Key point: reinforcers and punishers are defined by their effects on behavior, not by your intentions... While watching the 3 Stooges, 5-year-old Billy pokes his 4-year-old sister. His father says, “Stop that!” A minute later, Billy does it again, and his father yells at him. A few seconds later, Billy laughs and gives little Kelly another poke. In terms of operant conditioning, why did the poking response increase rather than decrease? Answer: the scoldings are a reinforcer.

A B C Antecedents Analyzing Behavior The ‘s of Operant Conditioning Discriminative stimulus: a stimulus that comes before a response; it signals that if the response occurs, it may be reinforced. Delta stimulus: a stimulus that comes before a response and signals that it will not be reinforced.

A B C Analyze this... Analyzing Behavior The ‘s of Operant Conditioning Analyze this... Billy’s father leaves the room for a few minutes to answer the telephone. While he is out of the room, Billy stops poking his sister. But when his father comes back in, Billy starts doing it again. Why? Answer: The father’s presence is an SD; it signals that poking responses will be reinforced by attention. His absence is an S . It signals that poking responses will receive no attention.

A B C Antecedents Analyzing Behavior The ‘s of Operant Conditioning Discrimination: a situation in which a certain response (like poking) is more likely to occur when one stimulus is present (father present) than when another stimulus is present (father absent). Stimulus control: control of a response by a discriminative stimulus. Billy’s poking response is under stimulus control: his father’s presence.