Reversal performance by rats following overlearning with and without irrelevant stimuli.

Abstract

In 2 separate experiments, degree of learning (moderate vs. overlearning) was manipulated simultaneously with irrelevant cues conditions (present vs. absent) during discrimination learning and reversal by rats. Massed position discrimination training was given to criterion or to 125-150 trials beyond criterion at which time reversal began. Reversal also was taken to criterion. In direct contrast to earlier studies, overlearning significantly retarded reversal performance in both experiments. The results also suggest that reversal performance following overlearning is made even more difficult by the presence of irrelevant stimuli. The fact that some studies have found that overlearning facilitates reversal and other studies have not, therefore, apparently is not due solely to the fact that the successes included irrelevant cues while the failures did not.