Lectures on diseases of the nervous system : delivered at Guy's Hospital / by Samuel Wilks.

Date:
1878
Catalogue details

Licence: Public Domain Mark

Credit: Lectures on diseases of the nervous system : delivered at Guy's Hospital / by Samuel Wilks. Source: Wellcome Collection.

Provider: This material has been provided by the Royal College of Physicians of Edinburgh. The original may be consulted at the Royal College of Physicians of Edinburgh.

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    INTEODUOTORT REMARKS ruled by the ganglionic nervous forces; you may witness the fact daily in the wards of the hospital, in patients whose brains and spinal cords are irretrievably diseased. Tou see also how many operations of the human body are due to forces residing in the spinal cord ; and that this cord is again overruled by the large cerebral hemispheres. All these systems are intimately united ; even the sympathetic is closely joined to the spinal to regulate the functions of the viscera, and therefore you might infer that some of the opera- tions going on in the organism within might at times be made perceptible to us. This relationship between the two systems is so important that I shall have to refer to it again. The nervous system, as generally described by physiologists, is made up of two parts, the force-producing elements and the conducting cords, analogous to a galvanic battery and its connecting wires. The grey or ganglionic substance is the potent material and the nerves are the conductors ; the former is the seat both of the active power, which is exhibited as the motive force, and also the highly vitalized receptacle for impressions from without. As regards the nerves, it would appear, from experiments lately made, that those for motion and sensation are structurally alike, and therefore would convey equally well sensory or motory vibrations. The grey or potential matter in the spinal cord can be stimulated to action from any irritation on the skin, and a movement be reflected back to the part touched. This occurs equally well or better where the spinal marrow has no connection with the sensorium alone ; but, of course, under these circumstances, the animal has no sensation (or feeling in the ordinary sense of the term), nor voluntary power over the body. The brain, when connected with the cord, receives impressions from it, and elaborates them in a manner so that they become to us as mental phenomena; but the latter do not free themselves from the impressions which caused them, for these continue ever after to be intimately associated or even composed both of sensations and movements. This is established by the late experiments of Hitzig and Ferrier, who found not only, as the older experimenters had already discovered, that irritating the coi*pus striatum and brain over it would produce move- ments, but that irritation of particular convolutions would cause uniform and definite actions on certain muscles of the animal, as, for example, movements of the front and hind leg or ear re- spectively, according to the parts operated on. This would lead us to the belief that the various actions of the body are not merely set agoing by the voluntary power exerted on the spinal cord by the brain, but that each portion of the brain has its own separate func- tion in relation to the several movements, and even that the mental