Lever displacement during a discrimination differentiation.

Abstract

Maximum displacement of a rat response lever was recorded under 2 schedules: (a) programed variable duration SD and S[DELTA] periods with reinforcement only for SD presses between 23.54[degree] and 28.64[degree] and (b) the same reinforcement requirements as in (a) but with S[DELTA] initiated only by a "wrong" SD press, and prolonged by any S[DELTA] press. Under (a), SD distributions differed significantly from their companion S[DELTA] distributions, and both mean displacement and variability were greater in S[DELTA] than in SD. Under (b), SD distributions differed significantly from S[DELTA] distributions, but they were correlated. Mean displacement was about the same in SD and S[DELTA], but variability was greater in S[DELTA].