| Abstract: | The topographical distribution of vestibulospinal neurons in Deiters' nucleus was investigated by a microelectrode method. By contrast with observations made in morphological experiments, the localization of antidromically identified vestibulocervical (C-neurons) and vestibulolumbar (L-neurons) cells was found not to be limited to the ventral middle and rostral third of the nucleus (the forelimb region) and caudodorsal part of the nucleus (hind limb region), but to include the whole of the ventral and dorsal half of the nucleus, respectively. The zones of localization of these two groups of neurons are not confined to a single layer: C-neurons are found in the dorsal half of the nucleus and L-neurons in its ventrocaudal part also. Analysis of the distribution of monosynaptic IPSPs arising in response to activation of Purkinje cells in the vestibulospinal neurons showed that C-neurons are controlled chiefly from the forelimb zone of the cerebellar cortex whereas L-neurons are controlled equally by inhibitory influences from the forelimb and hind limb zones of the anterior lobe of the cerebellar cortex.L. A. Orbeli Institute of Physiology, Academy of Sciences of the Armenian SSR, Erevan. Translated from Neirofiziologiya, Vol. 11, No. 1, pp. 54–64, January–February, 1979. |
