ABSTRACT
In the analysis of behavior, we often speak of a discriminative stimulus as setting the occasion on which some response will be reinforced. Strictly, however, discriminative stimuli do not occasion responses; instead, particular stimulus properties occasion particular response properties. For example, imagine an experimental setting in which the form of a stimulus determines response location whereas its color determines response rate. Suppose the stimuli presented in a standard two-key pigeon chamber consisted of green or red circles or triangles. We could reinforce left-key pecking given circles and right-key pecking given triangles and fast pecking given green and slow pecking given red. If these contingencies established correlations between stimulus forms and response locations and between stimulus colors and response rates (cf. Catania, 1973, p. 106–109), it might be simpler to speak in terms of the several stimulus and response dimensions (form controlling location and color controlling rate) than to itemize the particular combinations of response properties occasioned by particular stimuli (e.g., fast left pecking occasioned by a green circle).
