Diagnosis of disorders of the cerebellar apparatus / by Tom A. Williams.

  • Williams, Tom A. (Tom Alfred), 1870-
Date:
1910
Catalogue details

Licence: In copyright

Credit: Diagnosis of disorders of the cerebellar apparatus / by Tom A. Williams. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    cortex through a cerebello-fugal path which decussates in the brachium conjunctivum en route to the opposite cortex. This view^ however, is not generally accepted. The impulses which reach the cerebellum in these various ways are there coordinated; and as a result of their impression, efferent impulses pass from the Purkinje cells on their way to regulate body tonus and position in accordance with the information gained. The efferent tract first reaches the dentate 'body; and it from there intromits via the brachium anterius with a second relay neurone in the red nucleus of the opposite side, whence it again decussates in Forell’s bundle and passes through the tegmental region of the mesencephalon, becoming more ventral and lateral in the pons, bulb and cord, in the latter more or less commingling with the anterio- lateral portion of the lateral pyramidal motor tract, and is supposed, with it, to mediate the activity of the motor cells in the anterior cornua of the spinal cord. It is supposed that other cerebello-fugal fibers control the ponto-bulbar nuclei in a similar manner, and thus regulate the ac- tivities of the muscles supplied by the motor cranial nerves. But the information by which the position of head and eyes is mainly regulated has another organ much more sensitive than the end-bodies in the extremities, neck and trunk. This is situated in the mem- branous labyrinth and consists of the terminations of the vestibular nerve there. Impressions are communicated to this by the move- ments of the endolymph within the utricle and semicircular canals. Thence they pass via the vestibular nerve to the nucleus of that name in the medulla, and from there probably in the lateral lemniscus and brachium conjunctivum to the homolateral and contralateral cere- bellar lobe and vermis; some of them, however, pass to the opposite oculomotor nuclei, and others directly to the nuclei of Deiters and von Bechterew. Physiology and Pathology.^—The receptive function of the cere- bellum is firstly orientation of the different parts of the body with regard to one another, and secondly perhaps a participation in the orientation of the body to its surroundings. It is possible, however, that this latter function is entirely cerebrospinal and that the impor- tance of the cerebellum in relation to it is confined to its proprio- ceptive aspect.