Representations of the body surface by climbing fiber responses in the dorsal paraflocculus of the cat.

Mechanical stimulation elicited climbing fiber responses in 22% of the 377 Purkinje cells isolated in the dorsal paraflocculus of cats anesthetized with sodium pentobarbital. The responsive units were not evenly distributed throughout the dorsal paraflocculus. In the posterior division, 37% (65/177) of the cells had climbing fiber responses elicited by tactile stimulation, whereas in the lateral and accessory divisions the units were mainly unresponsive to tactile stimulation. Eleven of the 174 cells were responsive to tactile stimulation in the lateral division and only one climbing fiber response was driven in the 26 cells isolated in the accessory division. The climbing fiber representation was mainly of the ipsilateral forelimb and hindlimb with only a few responses representing the face. About half of the hindlimb representation was encountered in a patch located in the most medial part of the posterior division. No consistent location was identified between animals for the rest of the representations, which were intermingled among unresponsive units. The receptive fields of the majority of the forepaw and hindpaw representation included areas of the lateral toes; only a few responses represented the medial parts of the paw.