In the late nineteenth century, psychologist Edward Thorndike proposed the law of effect. The law of effect states that any behavior that has good consequences will tend to be repeated, and any behavior that has bad consequences will tend to be avoided. In the 1930s, another psychologist, B. F. Skinner, extended this idea and began to study operant conditioning. Operant conditioning is a type of learning in which responses come to be controlled by their consequences. Operant responses are often new responses.
Just as Pavlov’s fame stems from his experiments with salivating dogs, Skinner’s fame stems from his experiments with animal boxes. Skinner used a device called the Skinner box to study operant conditioning. A Skinner box is a cage set up so that an animal can automatically get a food reward if it makes a particular kind of response. The box also contains an instrument that records the number of responses an animal makes.
Psychologists use several key terms to discuss operant conditioning principles, including reinforcement and punishment.
Reinforcement is delivery of a consequence that increases the likelihood that a response will occur. Positive reinforcement is the presentation of a stimulus after a response so that the response will occur more often. Negative reinforcement is the removal of a stimulus after a response so that the response will occur more often. In this terminology, positive and negative don’t mean good and bad. Instead, positive means adding a stimulus, and negative means removing a stimulus.
Punishment is the delivery of a consequence that decreases the likelihood that a response will occur. Positive and negative punishments are analogous to positive and negative reinforcement. Positive punishment is the presentation of a stimulus after a response so that the response will occur less often. Negative punishment is the removal of a stimulus after a response so that the response will occur less often.
Reinforcement helps to increase a behavior, while punishment helps to decrease a behavior.
