Measurement of Drug Effects on Stimulus Control

Operant behavior is defined as behavior that is maintained by its consequences. If a consequent event follows behavior only in the presence of certain discriminative stimuli (S D ), responding becomes differentiated with respect to the discriminative stimuli. When this occurs, it can be said that responding is under stimulus control (Terrace, 1966). In order to determine whether behavior is under stimulus control, a stimulus-generalization gradient is often obtained, i.e., the discriminative stimulus is varied systematically along some dimension, and responding is measured in the presence of several different values of the stimulus. Stimulus control is demonstrated when the probability of responding varies systematically as a function of different values of the stimulus (for a discussion of procedures for obtaining generalization gradients and interpreting them, see Rilling, 1977, and Ray and Sidman, 1970). These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.