[Spatial organization of vestibular effects on neurons of the fastigial nucleus in the cat]

Abstract

Cerebellar fastigial neurons activated by stimulation of vestibular nerve and the lateral vestibular nucleus of Deiters, were studied in cats. Over 2/3 of the neurons synaptically activated by stimulation of vestibular nerve are localized in the caudal half of the fastigial nucleus. Over half of these fastigial neurons could be activated antidromically by stimulation of the contralateral Deiters nucleus. 81% of these neurons antidromically activated by stimulation of ventral region of the contralateral Deiters nucleus were distributed in the caudal half of the fastigial nucleus and the remaining 19%--in the rostral part of the nucleus. Bilateral stimulation of the dorsal part of Deiters' nucleus antidromically activated the fastigial neurons in medial and rostral regions of the nucleus. There was no fastigial neuronal projections to the ventral half of the ipsilateral Deiters' nucleus. Orthodromic action potentials could be produced by stimulation of the ipsilateral Deiters' nucleus in the neurons of rostral part of the fastigial nucleus.