Differential outcomes effect in simultaneous matching to sample with reinforcement independent of response

Abstract

Two groups of pigeons were used to evaluate the differential outcomes effects in matching, oddity and arbitrary matching-to-sample tasks with response-independent reinforcement. In the same-outcomes group (SO), all positive trials terminated in the same reinforcer, irrespectively of sample stimuli; in the differential outcomes group (DO), the reinforcer at the end of a positive trial depended on the sample stimulus presented on this trial. In either group, negative trials ended without any programmed consequence. The results show that in each task the discrimination was established more easily in the DO group than in the SO group.