The effect of previous experience upon operant performance following cerebellar lesions in the rat

Abstract

Lesions of the fastigial nuclei and cerebellar vermis, but not lesions of the dentate nuclei, were found to produce marked performance deficits on a differential reinforcement of low rates (DRL) schedule of reinforcement. This deficit was characterized by an abnormal number and distribution of responses within the schedule interval. Lesions, however, did not produce a deficit following preoperative training or when subjects were tested on a fixed-interval (FI) schedule. In addition, when DRL and FI performance was contrasted, all subjects were responsive to schedule contingencies. Results suggest that the DRL deficit following cerebellar lesions is due to a tendency to perseverate in response strategies, and is not related to a global disruption of timing or a pervasive inability to suppress responding.