Diseases of the spinal cord.

  • Bramwell, Byrom, Sir, 1847-1931.
Date:
1882
Catalogue details

Licence: Public Domain Mark

Credit: Diseases of the spinal cord. Source: Wellcome Collection.

Provider: This material has been provided by UCL Library Services. The original may be consulted at UCL (University College London)

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    the larger division (which, according to Flechsig, usually con- tains from 91 to 97 per cent, of the whole) crosses over to the left side of the spinal cord, and proceeds down the left side of the cord in the lateral column, constituting the crossed pyramidal tract of the left lateral half of the cord. The smaller sub-division (which, according to Flechsig, usually con- tains from 3 to 9 per cent, of the whole) does not decussate, but passes down the same (right) side of the cord in the anterior column, constituting the direct pyramidal tract (or column of Tiirck), the position of which has been already described. Voluntary motor impulses, then, are chiefly carried to our segment by fibres which pass to it from the crossed pyramidal tracts in the lateral columns. The fibres carrying motor impulses to inferior segments simply pass through our segment. (See fig. 14.) The fibres destined for our segment itself leave the main motor tracts (direct and crossed pyramidal tracts) as represented in fig. 15; enter the grey matter; and pass to the anterior cornu. Some of them probably become connected with the multi- polar nerve cells. Others probably pass directly into the anterior nerve roots. After entering the grey matter, the fibres of the pyramidal tract are supposed to divide and sub- divide, and finally to form connections with the delicate fibrils of Gerlach's nerve network, in which, as I have pre- viously stated, the branches of the multipolar nerve cells (except the axis cylinder process) are supposed to terminate, as is represented in figure 19. Fig. 19. Supposed union of a nerve fibre with a nerve cell. The processes of the cell subdivide into a minute network (Gerlach's nerve network), in which the fibre, a, also looses itself.