ACQUISITION OF CONCURRENT DISCRIMINATION WITH MULTIPLE SCHEDULES: EXPLORING A PROCEDURE FOR FUNCTION CLASS FORMATION IN RATS

Abstract

Studies on stimulus class formation usually require training of baseline discriminations that comprise multiple interrelated simple and/or conditional discriminations. The purpose of the present study was to replicate the acquisition of baseline discriminations of a previous study with rats as subjects, introducing changes in the procedure in order to make more efficient the baseline training. Six albino rats (Rattus norvegicus) were exposed to a successivesimple discrimination training procedure with auditory stimuli in long duration sessions. Two different auditory stimuli (A1 and B1) were correlated to a variable ratio schedule (VR) and two other stimuli (A2 and B2) were correlated to differential reinforcement of low rates schedule (DRL). Five out of the six rats acquired the discriminations showing two distinct patterns of response (high rates in the VR schedule and low rates in the DRL Schedule) under control of the auditory stimuli. Results suggest that the use of a multiple schedule with auditory stimuli in long duration sessions may be a fast and efficient alternative to build a baseline repertoire in studies on functional class formation with auditory stimuli and rats as subjects.Key-words: variable ratio, differential reinforcement of low rates, auditory stimulus, Rattus norvegicus