GEN. V. Paroniria. Sleep-disturbances. Sometimes only a single sense thus roused, and why. Hence sleep-talking, sleep-walk ing or somnambulism, and night pollution. Now as the stimulant force of our ideas in dreaming, is often sufficient to rouse the external senses generally, and to awake us all of a sudden; it may be of such a kind, and just of such a strength, as to excite into their accustomed action the muscles of those organs or members only which are more immediately connected with the train of our dreams or incoherent thoughts; while every other organ may still remain torpid. And hence the muscles chiefly excited being those of speech, some persons talk, or the muscles chiefly excited being those of loco-motion, other persons walk, in their sleep, without being conscious, on their waking, of any such occurrence*. And by the same means we may easily account for the third species of the genus, or that which consists in dormant and involuntary salacity. SPECIES I. PARONIRIA AMBULANS. Somnambulism. Sleep-walking. THE MUSCLES OF LOCO-MOTION EXCITED INTO THEIR GEN. V. In profound powers of the mind and body, except the involuntary organs, in a state of torpitude. IN profound sleep all the faculties of the mind, as well as all the voluntary organs of the body, are in a state of inactivity or torpitude, and the only organs that preserve their active tenour are the involuntary ones: so that in this state there is neither thought nor idea of any kind. * Hennings, Von den Träumern und Nachtwandlern. Weimar 1784. Horst, De Natura, Differentiis, et Causis eorum qui dormientes ambulant, &c. Leips. 1593. 8vo. GEN. V. SPEC. I. Paroniria In dreaming some of the mental faculties only sleep or are torpid, while the others, like the involuntary organs of the body, continue wakeful or active: the somnolent ambulans. faculties, we have already observed, are the will, the perception, and the judgement; the wakeful are the memory walking. and the imagination. Somnambulism. Sleep In dream ing some of faculties only sleep, the mental as the will, the perception, and the judgement: while the continues Not difficult to know why the involun tary organs do not re quire rest: nor why the will and the judgement sooner become dor mant than It would not be difficult, if we had time, to show why the involuntary organs do not require rest, or, in other words, become torpid like the voluntary; nor why the will and the judgement sooner associate in the general sleep of the external senses than the imagination, but this would carry us too far into the subject of animal physiology. There are two physiological remarks, however, imagination which it is necessary to make in explanation of the mor- awake. bid affection immediately before us. The first is, that sleep is a natural torpitude or inertness induced upon the organs of the body (with the exception of the involuntary) and the faculties of the mind by fatigue and exhaustion. And the next is that, in the production of sleep, it is not necessary that all these powers of body and mind should have been equally exposed to exhaustion: for, such is the effect of association and habit, that as soon as one faculty or organ feels fatigue, or becomes exhausted, the rest participate in the same condition, and tion. the sleep or torpitude becomes common to the whole. It is hence the body is made drowsy by mental study, and the mind by corporeal labour; that muscular exercise wearies all the senses, and the exertion of the senses wearies the muscles: though there can be no doubt that the general tendency to sleep is also partly superinduced by the indirect exhaustion sustained by the organs or faculties that have been less employed, in consequence of the share of sensorial energy which, as from a common stock, they have themselves contributed towards the support of the more active and hence more debilitated association powers. Now it sometimes happens, either from disease or pe- Some of the culiarity of constitution, that all the external organs of external sense do not associate in the general action that has taken sense do not the imagina Sleep is a pitude induced by fatigue and exhaustion. The exsome of the powers of haustion of and mind only se the body the result of condary, or with the rest. organs of GEN. V. SPEC. I. Paroniria ambulans. Somnambu lism. Sleep walking. in every in stance associate in the torpor or sleep of the rest: times some awake sud the rest con tinue to sleep. perceive objects while asleep and if the tenour of the dream place, or yield alike to the general torpor to which it gives rise; and that the auditory, the optical, or some other sense, continues awake or in vigour, while all the rest are become inert; as it does also, that such particular sense, like the muscles of particular members, as observed a page or two above, is awoke or re-stimulated into action in the midst of the soundest sleep by the peculiar force and bent of the dream, while the rest still sleep on and are unaffected. If the external organ of sense thus stimulated be that of sight, the dreamer may perceive objects around him, and be able to distinguish them and if the tenour of denly while the dreaming ideas should as powerfully operate upon the muscles of loco-motion, these also may be thrown into their accustomed state of action, and he may rise from his bed and make his way to whatever place the drift of his dream may direct him, with perfect ease, and free from danger. He will see more or less distinctly in proportion as the organ of sight is more or less awake: yet from the increased exhaustion, and of course, increased torpor of the other organs, in consequence of an increased demand of sensorial power from the common stock, to supply the action of the sense and muscles immediately engaged, every other sense will probably be thrown into a deeper sleep or torpor than if the whole had been quiescent. Hence the ears may not be roused even by a sound that might otherwise awake the sleeper. He may be insensible, not only to a slight touch, but a severe shaking of the limbs; and may even cough violently without being recalled from his dream. Having accomplished the object of his visionary pursuit, he may safely creased, and return, even over the most dangerous precipices, for he act powerfully upon the locomotive muscles, he may walk, while the rest of the mind and body are dormant. The dormancy of the sleeping organs hereby in why. Irritability of habit sees them distinctly, to his bed; and the organ of sight being now quite exhausted, or there being no longer any occasion for its use, it may once more associate in the general inactivity, and the dream take a new turn, and consist of a new combination of images. Somnambulism occurs in many persons without any maoften a pre nifest predisponent cause, though it is generally con disponent cause. SPEC. I. Somnambu state of the cause. nected with a considerable irritability of habit. A morbid GEN, V. state of the stomach, where this habit exists, has very Paroniria frequently proved an exciting cause of which Dr. Yeates ambulans. has given us an example in the case of a young gentle- lism. Sleepman of ten years of age related in the Medical Transac- walking. tions *. He was of a delicate frame, often troubled with Morbid sickness; sometimes rejected his food undigested, after stomach having lain two days in his stomach; his bowels were often an exciting costive, and the stools were dark, offensive, and ill-formed. The sympathetic symptoms were frequent head-aches Exemplified. with occasional stupor, general coldness of the skin, and limpid urine. After being in bed for about two hours he was wont to start up suddenly as in a fright, dart rapidly into the middle of the chamber, or of the room adjoining, and walk about with much agitation. In this state he would run over quickly, but incorrectly, the transactions of the day; and he once attempted to spell a word which in the day time he had spelt wrong, in doing which he jumbled a number of letters together. When spoken to he would make a rational reply; and in one of his sleeping perambulations he called for an epitome of the History of England which he was in the habit of reading the nurse brought him a book, but not the one he called for: on perceiving the difference he immediately threw it from him with great violence, and with expressions of anger and disappointment. On these occasions his eyes were wide open, though he did not seem conscious of seeing, nor of his situation at the time. It was, says Dr. Yeates, a perfect state of dream throughout, though partaking of the acts of the waking state, for he would avoid objects walking about the room. His face was quite pallid at the time. In this case much of the nervous hurry and agitation seems to have depended upon the debilitated and irritable state of the patient's frame. But where the affection proceeds from idiosyncrasy, or where there is no disturb ance of the general health, the dreamer often proceeds This case produced by nervous irritability, the hurry of the sleepwhere no and hence walk: such irritability, the dreamer often pro GEN. V. Paroniria far more coolly and collectedly: and the eye-lids, instead of being wide open as though staring, are often not more than half-unclosed, in some cases even less than this; which has given occasion to marvellous stories of somnambulists walking over dangerous places, or avoiding ceeds cooly dangerous objects with their eyes completely shut all Somnambu lism. Sleepwalking. and collect edly. The eyes are more or less open: but from their winking, have sometimes been de scribed as the time. The remedial treatment it may be necessary to pursue we shall defer till we have briefly noticed the succeeding species, as the same treatment will apply to the whole. closed. Remedial treatment. GEN. V. General principle explained under the preceding species. speech sti mulated by SPECIES II. PARONIRIA LOQUENS. Sleep-talking. THE MUSCLES OF SPEECH EXCITED INTO THEIR ACCUS- It is not necessary to dwell upon this species, as we have SPEC. II. already explained the general principles of the inordinate action in the preceding pages. As the train of ideas which form the dream, when peculiarly lively and immediately connected with the organs of locomotion, may stimulate those organs into their accustomed activity, and thus give the dreamer a power of walking without conOrgans of sciousness; in like manner if a similar train of dreaming ideas be immediately connected with the organs of speech, these may also be equally influenced, and the dreamer be able to talk without being conscious of it, or having any recollection of such exertion when he awakes. And as, for reasons already specified, the organ of sight is sometimes, in the same way, roused from a state of sleep or torpitude to a state of wakefulness, while all the other external senses continue somnolent, or, from idiosyncrasy or some local or accidental cause, do not join in the general repose, but continue vigilant during its dominion the train of dreaming ideas. |