Volume 1
The physiological anatomy and physiology of man / by Robert Bentley Todd and William Bowman.
- Date:
- 1845-1856
Licence: Public Domain Mark
Credit: The physiological anatomy and physiology of man / by Robert Bentley Todd and William Bowman. 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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![4 chap, xi.] FUNCTIONS OF THE ENCEPHALON. 357 states of emotion. In such cases, the nerves most affected are those connected with the mesocephale and medulla oblongata, denoting^an excited state of those portions of the encephalon. Of these diseases the most remarkable are hysteria and chorea ; both of which may be induced either by a cause acting primarily upon the mind, or by functional disturlwinee of the body, as deranged assimilation, in per- sons of a certain character of constitution. In hysteria, the globus, the tendency to cry or laugh, the disturbed breathing, the variously deranged state of the respiratory acts, all denote affection of most, if not all, the nerves coming from those segments. In chorea the fre- quent movements of the face and eyes, the peculiar and very charac- teristic mode of protruding the tongue, the impaired power of articulation, are dependent on an altered state of that part in which the portio dura of the seventh pair, the third, fourth, and sixth, and the ninth nerves are implanted. In both diseases the principal central disturbance is in the mesocephale; and that may be caused either by the direct influence of the mind upon it, or by the propa- gation of a state of irritation to it from some pait of the jK*ri- phery. Chorea, even of the most violent and general kind, is very commonly produced by sudden fright; and it is well known how frequently mental anxiety or excitement developes the paroxysm of hysteria. There is no part of the cerebro-spinal centre which appears to exercise such extensive sway over the movements and sensations of the body as this j>ortion, the mesocephale, which we regard as the centre of emotional actions. Its influence* extends upwards to the cerebral convolutions—backwards to the cerebellum —downwards to all the nerves of sensation and motion. Through its connexion with the posterior horns of the spinal gray matter, it can excite the sensitive as well as the motor nerves of the trunk. Hence it is not to be wondered at that a highly disturbed state of this centre is capable of deranging all the sensitive as well as motor phenomena of the body, and even the intellect. Hence we may explain the extraordinary movements in hydrophobia and general chorea, in both of which diseases this part of the nervous centre is doubtless affected. It has often been remarked howr much more powerful are the voluntary actions when prompted by some strong emotion, than when excited only by an effort of the will. Rage, or despair, is able to magnify the power of the muscles to an incalculable degree. This may be due to the increased stimulus derived from the in- fluence of the centre of emotion being conjoined with that of the centre of volition.](https://iiif.wellcomecollection.org/image/b28043327_0001_0379.jp2/full/800%2C/0/default.jpg)
