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Study of neuronal structures of the brain stem which produce rapid reactions in reticulo-spinal pathways

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Abstract

The total electrical discharges of the ventral and ventrolateral funiculi of the 11th thoracic segment of the spinal cord in response to stimulation of different points of the pons varolii and the medulla oblongata between frontal planes P-2 and P-12 were investigated in decerebrated cats. Regions were found corresponding to the location of the oral and caudal reticular nuclei of the pons and the rostral section of the reticular giant cell nucleus whose stimulation caused a short-latent discharge in the ventral funiculus (latent period 1.6–1.9 msec) with maximum amplitude. It was concluded that such a discharge is due to the direct stimulation of a rather homogeneous group of fast-conducting reticulo-spinal fibers which terminate mainly in the ventral funiculus and which have an average rate of conduction of 131 m /sec. When the same regions were stimulated, the short-latet discharge of the ventro-lateral funiculus had a considerably lower amplitude and was accompanied by a powerful, late discharge with a latent period of about 3.3 msec. It was assumed that this funiculus consists mainly of fibers with a lower rate of conduction which originate in a broader region of the medial RF of the brain stem. Stimulation of contralateral regions of the reticular formation of the medulla oblongata evoked only a weak short-latent discharge in the ventral funiculus; the late component of the discharge in this case was considerably stronger.

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Authors
  1. I. S. Bezhenaru
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Additional information

A. A. Bogomolets Institute of Physiology, Academy of Sciences of the Ukrainian SSR, Kiev. Translated from Neirofiziologiya, Vol. 3, No. 3, pp. 274–283, May–June, 1971.

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Bezhenaru, I.S. Study of neuronal structures of the brain stem which produce rapid reactions in reticulo-spinal pathways. Neurophysiology 3, 205–212 (1971). https://doi.org/10.1007/BF01065494

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  • DOI: https://doi.org/10.1007/BF01065494

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