Effects of cerebellar lesions on activity, social interactions, and other motivated behaviors in the rat.

Abstract

In rats, lesions of the cerebellar fastigial nucleus, but not lateral nuclear lesions or cerebellar cortical lesions, resulted in significant reductions in activity open-field exploratory behavior and social interactions. These deficits showed no recovery over a 4 wk testing period and were not related to the motor effects of the lesions. Other motivated behaviors, such as eating, grooming, gnawing and pain responsiveness, were minimally affected. The existence of 2 separate fastigial output pathways to neurobehavioral substrates was suggested. One of these is the direct fastigio-bulbar pathway, which mediates the eating, grooming and gnawing behaviors elicited by fastigial stimulation. The other is the ascending fastigial projection to limbic structures, which may mediate fastigial influences on activity and social interaction.