Practical and pathological researches on the various forms of paralysis.

  • Edward Meryon
Date:
1864
Catalogue details

Licence: Public Domain Mark

Credit: Practical and pathological researches on the various forms of paralysis. 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 third kind of fibres enter the cord obliquely, and imme- diately spread out in different directions; some fibres passing into the posterior cornua, whilst others diverge and take a longitudinal course, either downwards or upwards, within the posterior white columns : but whether any of these latter are continued as far as the brain, is a question which has not yet been determined. Wagner regards them as purely sensitive fibres which, without being connected with the ganglionic cells in the spinal cord, pass directly upwards to the brain, and there excite sensation. But experimental observations and pathological cases are not wanting to show that the anterior columns are not the exclusive conductors of the influence of the will to the anterior nerves, and that the posterior white columns are not the sole channels of communication between the posterior nerves and the brain. With respect to the anterior columns, an explanation is afforded by the connecting links which have been described between the anterior roots and the longitudinal fibres in the anterior cornua; and a more obvious clue is given to account for the transmission of sensation—at least as far as the spinal cord is concerned—by the course and distribution of the poste- rior roots, and by the longitudinal nerve-fibres contained in the grey substance. Dr. Brown-Sequard has been led, by his experiments, to the conclusion that the transmission of sensitive impressions to the sensorium takes place by both cells and nerve-fibres united together,* but that the grey matter is the principal conductor of the sensitive impressions in the spinal cord. The very objec- tion, however, which he admitted in opposition to Longet, who supposed that the sensorium received sensitive impressions only from the posterior columns, exists to a greater degree in respect of the notion that cells transmit such impressions. * Lectures on the Physiology and Pcathology of the Central Nervous System, delivered at the Royal College of Surgeons of England in May, 1858, p. 23.— Herein Dr. B. S^quard descriljes the result of making a trausveree incision of the posterior columns of the spinal marrow as inducing liyperivsthesia l)ehind the section ; from which he infers that the posterior columns of the s])inal cord and medulla oblongata are not the channels for transmitting sensible impressions from their peripliery to the brain ; but if the grey matter be divided, as well as the posterior columns, then sensibility is lost.
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