The Influence of Prereversal Experience on Reversal Learning in White Rats

Abstract

The purpose of the present study was to investigate the effects of reward and non-reward in reversal learning. In Experiment I, 36 white rats were trained on a black-white discrimination problem in a Y-maze. The training consisted of three stages; original learning, prereversal experience and reversal learning. The original learning continued until each S reached the criterion of 18 correct out of 20 responses on successive two days, with all responses correct on the final day. Ss were then divided into three groups, and were given prereversal experience which differed by groups. Ss of group N-P received 20 rewarded prereversal trials to the stimulus card that had initially been negative but which was to be positive during the subsequent reversal trials : and, conversely, Ss of group P-N received 20 non-rewarded trials to the stimulus card that had initially been positive but which was to be negative during the reversal. Ss of the control group received no prereversal experience. All Ss were then trained on the reversal problem. The results of the reversal learning were summarized in Table 1. Group P-N was superior to the control group, whereas group N-P did not differ from the control group.
In Experiment II, 33 white rats were trained on a position discrimination problem in a T-maze. The training consisted of three stages ; original learning, prereversal experience and reversal learning. The original learning continued for 3 days, with 10 trials on each day. Ss were then divided into three groups, and were given prereversal experience for 2 days (20 trials), and were finally trained on the reversal problem for 5 days. The results of the reversal learning are shown in Table 3, which represents superior performance of group P-N and inferior performance of group N-P to the control group. The results of the above two experiments support the uniprocess theory which emphasizes the role of inhibition in discrimination learning.