Representation of vibrissae inputs through the climbing fiber pathway in lobule VII of the adult rat cerebellar vermis.

The present study gives a detailed description of the functional characteristics and of the topographic distribution of Purkinje cell (PC) responses, mediated through the climbing fiber pathway and elicited by mechanical stimulation of two different rows (A and C) of vibrissae in a circumscribed region of the posterior vermis of the rat cerebellum. Experiments were carried out on normal adult rats under barbiturate anesthesia. PCs were recorded in an area extending 1500 microns laterally to the midline in the vermal part of lobule VII contralateral to the stimulation.

[Existence of very weak level of residual multiple innervation of Purkinje cells through climbing fibers in the cerebellum of the normal adult rat].

Extra- or intracellular unit responses of Purkinje cells to the activation of climbing fibres were recorded in the cerebellum of adult rats. Out of 1.719 cels studied, only 4 were found to be innervated by more than one climbing fibre.