ROTOROD SENSORIMOTOR LEARNING IN CEREBELLAR MUTANT MICE

Lurcher mutant mice, characterized by degeneration of cerebellar granu le and Purkinje cells, were compared to normal littermate controls in a rotorod test, consisting of a wheel turning at constant speed which required on the part of the animal postural adjustments in order to ma intain equilibrium. Identical baseline rates for the two groups were a ssured by changing the speed and size of the rotating rod. Although bo th groups were able to learn the task, the fall latencies of normal mi ce exceeded those of lurchers. These results indicate that cerebellar cortical atrophy does not abolish this form of sensorimotor learning. However, brain-damaged animals are unable tb reach the same level of p erformance as normal animals. In contrast to the results in lurcher mu tants, no sensorimotor learning was displayed by hot-foot mutants and staggerer mutants.