Cerebellar Purkinje cell projection to the peripheral vestibular organ in the frog.

Neurones located 200 to 300 microns from the surface of the auricular lobe of the frog cerebellar cortex, and identified as Purkinje cells, were activated antidromically from the eighth cranial nerve. A parallel anatomical study confirmed the existence of this projection. On the basis of these findings the existence of a cerebello-vestibular efferent system is postulated, the precise significance of which is as yet unclear. However, since Purkinje cells in other species have an inhibitory action on their target cells, the Purkinje efferent system to the vestibular organ may have an action similar to that ascribed to the olivo-cochlear bundle upon the cochlea, that is, to serve as an inhibitory control system.