Abstract
The influence of the red nucleus on activity in various groups of fibers of the medial reticulospinal tract was investigated in cats anesthetized with chloralose and pentobarbital. The red nucleus was found to exert monosynaptic excitatory influences on many neurons of the medial reticular formation having axons with high (60–105 m/sec) and average (45–60 m/sec) conduction velocities. Repetitive stimulation of the red nucleus as a rule evokes an increase in the frequency of spontaneous activity in these fibers, characterized by grouping of spikes into volleys. Most neurons with slowly conducting axons (10–45 m/sec), on the other hand, are activated polysynaptically or not at all by the red nucleus. Their spontaneous activity, with a uniform distribution of its spikes, is inhibited by stimulation of the red nucleus. The same character of rubro-reticular connections persists even after destruction of tecto- and interstitio-bulbar projections. The functional organization of the rubro-reticulospinal system is discussed.
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A. A. Bogomolets Institute of Physiology, Academy of Sciences of the Ukrainian SSR, Kiev. Translated from Neirofiziologiya, Vol. 7, No. 5, pp. 532–540, September–October, 1975.
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Shapovalov, A.V., Gokin, A.P., Pilyavskii, A.I. et al. Rubrofugal influences on unit activity in the medial reticulospinal tract. Neurophysiology 7, 413–420 (1975). https://doi.org/10.1007/BF01067812
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DOI: https://doi.org/10.1007/BF01067812