Somatosensory climbing fiber responses in the caudal posterior vermis of the cat cerebellum.

Tactile stimulation of the body surface elicited climbing fiber responses in 5% of the 839 Purkinje cells recorded in the caudal posterior vermis (lobules VII-IX) of cats anesthetized with sodium pentobarbital. The cells responsive to tactile stimulation were mainly encountered around the prepyramidal fissure between lobules VIIb and VIIIa. This region was characterized by responses representing only selective areas of the ipsilateral face, forepaw, hindlimb, or proximal tail-pelvic territory. Climbing fiber responses representing the face and forepaw were encountered more laterally and those representing the proximal tail-pelvic area more medially. Tactile representations of the body surface are located within the same cortical domain as other climbing fiber inputs, which suggests that the caudal posterior vermis is a multifunctional region of the cerebellum.