Three-term contingency

The three-term contingency (also known as the ABC contingency) is a psychological model describing operant conditioning in three terms consisting of a behavior, its consequence, and the environmental context, as applied in contingency management. The three-term contingency was first defined by B. F. Skinner in the early 1950s.^[1] It is often used within ABA to alter the frequency of socially significant human behavior.

Components[edit]

Antecedent[edit]

The antecedent stimulus occurs first in the contingency and signals that reinforcement or punishment is available on the contingency of a specific behavior. A discriminative stimulus, or S^D, directly affects the likelihood of a specific response occurring.^[2]

Behavior[edit]

The behavior, also referred to as the response, is any observable and measurable action a living organism can do. In the three-term contingency, behavior is operant, meaning it changes the environment in some way.