Effect of overtraining on reversal and extradimensional shifts.

Abstract

Thirty-two rhesus monkeys were trained to criterion in a Wisconsin General Test Apparatus to respond to 1 dimension of a 2-dimensional discrimination task and then to respond either to the previously negative stimulus (reversal shift-RS) or to the previously irrelevant dimension (extradimensional shift-EDS). One-half of the subjects were given the discrimination shifts immediately upon reaching criterion in the original discrimination, while the other 1/2 received 200 training trials beyond criterion before undergoing the discrimination shifts. EDS was accomplished significantly faster than RS by both the criterion and the overtrained subjects. Overtraining had no effect.