Relative time effects on a discrimination based on the differential reinforcement of the water producing response in a schedule-induced-drinking-procedure

Abstract

Most previous attempts to condition schedule-induced drinking (SID) to arbitrary stimuli have involved classical-conditioning procedures, with mixed results. Considering the hypothesis that SID reduces to the operant reinforcement of the water-producing response, in a previous experiment the control of a stimulus on SID was established using a multiple water reinforcement schedule. To show that the operant discrimination of SID is sensitive to the duration of the extinction component of a multiple schedule as any other operant, food deprived rats were exposed to a 60-s random time food schedule and concurrently to mixed and multiple water-reinforcement schedules. On both schedules, reinforcement components lasted 32 s and rats lever-pressed for water on a 6-s random interval schedule. Extinction components lasted either 16 or 256 s, for each three rats. During the multiple schedule an operant discrimination was formed when the extinction component lasted 256 s, but not when it lasted 16 s. This result show that SID can be subjected to an operant discrimination and that such discrimination follows the principle of relative time.