Effects of differential outcomes on pigeon 's performance in delayed matching to sample tasks with reinforcement dependent and independent of the response

Abstract

Four groups of pigeons were employed in order to evaluate the effect of differential outcomes in delayed matching-to-sample tasks with response-dependent or response independent reinforcers. One group received only one type of outcome, independently of responding. A second group received differential outcomes, independently of responding. A third group received only one type of outcome, dependent on responding. A fourth group received differential outcomes, dependent on responding. The procedure included three matching conditions: with a zero delay, with a one-second delay, and with a three-second delay. In the first and second conditions, the discrimination index was higher in the groups with differential outcomes than in the groups with only one outcome. In the three-second delay condition, there were no differences between the groups with unique and differential outcomes.