Electrophysiological analysis of the trigemino-olivo-cerebellar (crura I and II, lobulus simplex) projection in the rat.

In albino rats the whisker area was electrically stimulated while climbing fiber responses were surveyed in the cerebellar hemisphere on the ipsilateral side. They were identified both deep in the intercrural sulcus, and in the posterior superior fissure. Histological examination has revealed that the response areas extend longitudinally from the dorsal surface of crus II to the ventral surface of crus I in the intercrural sulcus, and from the rostral surface of crus I to the caudal surface of lobulus simplex in the posterior superior fissure. These are supposed to be transmitted through direct trigemino-olivary projections.