Course of lectures on the physiology and pathology of the central nervous system. Delivered at the Royal College of Surgeons of England in May, 1858.

  • Brown-Séquard, Charles-Edouard, 1817-1894.
Date:
1860
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Licence: Public Domain Mark

Credit: Course of lectures on the physiology and pathology of the central nervous system. Delivered at the Royal College of Surgeons of England in May, 1858. 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 section. Much more recently, M. Schiff, repeating this experi- ment, found, on the contrary, that sensibilit}^ is not lost in any of the various parts behind the section. Messrs. Yulpian and Phili- peaux, who made this experiment some time after Schiff, positively declare that sensibility is completely and definitely lost. I have ascertained that the differences in the results of this experiment de- pend upon various circumstances. At first, if the least quantity of the central gray matter of the spinal cord is left undivided, sensi- bility persists (although much diminished) almost everywhere be- hind the section. Besides, there are parts in the neighborhood of the section, and behind it, which always remain sensitive. I will explain afterwards what is the cause of this partial persistence of sensibility. Whatever is this cause, if we perform the following experiment, we may obtain the most decisive results: The spinal cord having been laid bare in a large mammal, in the dorsal region, I divide transversely the whole of it, except only the two posterior columns (see Fig. 8, d\ and, after ten or fifteen minutes, or a little more, I find that all the usual means of exciting pain are applied in vain to the posterior limbs, so that these parts seem to be entirely deprived of sensibility. It results from this experiment, and from many others, in which the section was made nearer to the medulla oblongata, that the sensitive impressions do not pass along the pos- terior columns in their way to the encephalon. If the transmission of sensitive impressions does not take place along the posterior columns, it remains to be found what is the channel of this transmission. Is it the gray matter or some part of the lateral or anterior columns, or all or several of these constitu- ents of the spinal cord? As regards the lateral columns, if we divide them transversely in the dorsal region, we find that sensi- bility, instead of being lost, seems to be increased in the two pos- terior limbs. But if, in performing this experiment, the knife goes farther than the limits of the lateral columns, and divides a part of the central gray matter on the two sides, sensibility is then dimi- nished in the two posterior limbs. From these experiments, and from another one, which consists in a transverse section of the whole spinal cord except one of the lateral columns, it results that these columns, like the posterior, are not the channels of transmis- sion of any part of the sensitive impressions to the encephalon. It is not so with regard to the gray matter, as the following ex- periments show:— 1st. A transversal section of the whole posterior half of the spinal