What is a discriminative stimulus?

A discriminative stimulus is a cue or signal that indicates when a particular behavior will be reinforced. It essentially sets the stage for a behavioral response by highlighting the conditions under which reinforcement is available. For example, if a specific light is lit when a lever is pressed, the light serves as a discriminative stimulus; pressing the lever is likely to yield a reward only when that light is on.

Understanding this concept is crucial in reinforcement learning because it clarifies how organisms can differentiate between various stimuli in their environment and recognize which ones denote potential reinforcement for specific behaviors. This concept is integral to behavior modification techniques and is employed in various fields, including education and therapy, to shape and encourage desired behaviors effectively.