Lever displacement under a fixed-ratio schedule and subsequent extinction.

Abstract

Considering level presses of different displacements as different responses, some characteristics of FR-5 behavior of rats were variability comparable to that of extinction; as afunction of days of training, no "least-effort" tendency; no tendency to repeat reinforced responses; initially, a slight tendency to repeat non-reinforced responses; a decrease in mean displacement as a function of the ordinal number of the press following a reinforcement, i.e., a least-effort tendency within an FR (fixed-ratio) cycle. No significant correlations between displacement distributions in acquistion and in extinction were found. In extinction, successive presses to the same lever position occurred more frequently than expected on a chance basis.