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CHAPTER VIII.

SPECTRAL ILLUSIONS ARISING FROM A HIGHLY-EXCITED

STATE OF NERVOUS IRRITABILITY ACTING GENER

ALLY ON THE SYSTEM.

“ This bodiless creation Ecstacy
Is very cunning in.”-HAMLET.

The examples brought forward in the last chapter have, I trust, sufficiently illustrated the delusions liable to occur from an extremely morbid state of the nervous system. We had previously seen, that although an undue vividness of ideas directly results from certain changes induced in the circulating fluid, such changes might not only be traced to an inherent quality of the blood, arising from constitutional affections, or to the suppression of customary and natural evacuations, but that they might also ensue from adventitious agents of a chemical nature introduced into the system. In extending these researches, we further added to such causes of spectral impressions the influence of the nervous system, which nothing appeared more forcibly calculated to illustrate than inflammatory states of the brain or its membranes. Such extreme cases, therefore, of nervous irritability, which take their rise from manifest derangements of organic structure, give us the best reason to expect

that consequences no less singular in their nature may result from causes of a latent kind, where a highlyexcited state of the nervous influence, not often to be detected by actual examination, either generally or partially affects the circulating system.

Agreeably to the view which I have given of nervous fibres, they may be described as of three kinds. Fibres of the first description take their course from the external organs of sense, or from sensitive cavi. ties; and, in transmitting their influence to the sanguineous system, thereby induce corresponding sensations and renovated feelings. Fibres of the second kind are connected through a system of ganglions with the brain and spinal cord; their action on the blood being for the processes of secretion and assimilation, while, at the same time, they are capable of rendering the affections of the mind more or less vivid. Nery. ous fibres of a third class have no antecedent connexion with our mental states, but, in inducing muscular motion, obey the stimulus of the will. According to this notion, therefore, the particular mental excitability about to be described, arises from the influence of fibres of the first and second kind, and hence spectral illusions may occur, although the motific nerves should not be unduly excited; which not unfrequently happens when phantoms disturb the imagination of persons, who, from the regularity with which muscular motions at the same time obey the will, are supposed to be in perfect health. In the second place, spectral illusions may occur when there is an equally intense excitement of the motific nerves. In such a case, the particular affection is induced,

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which in Dr Good's Nosology bears the name of Carus Ecstasis. This writer has conceived, that in the diffusion of the motific influence, an excess of supply is equally felt by the extenor and flexor muscles. Hence the muscles are thrown into a rigid and permanent spasm, which gives to the body so erect a position, and so lofty and unalterable a demeanour, that the unhappy visionary, from this imposing air of inspiration, has not unfrequently both deluded himself and others with the notion, that his dreams were supernatural visitations. In the third place, the voluntary motific nerves may be irregularly incited; or, in other words, the balance of action subsisting between the flexor and extensor muscles may be so disturbed, that the frame will appear to be variously convulsed or incurvated. I believe this to be one of the varieties of Ecstasis which nosologists have, perhaps rather loosely, referred to Epilepsy; but, as all the causes of the latter affection are by no means decidedly pointed out, it would, for the present, be a prudent step not to disturb the appellation.* In many instances of epilepsy, there has been such a flow of spirits as to indicate, that a very powerful nervous influence was generally diffused throughout the human frame, while, as har

* Dr Wilson Phillip has shewn from experiments, that the nerves connected with voluntary muscles are more powerfully incited by mechanical than chemical causes of irritation. Thus we see the reason why Exostosis, or why foreign substances affecting the nervous system, should occasionally operate as causes of the convulsions of epilepsy; and why convulsions in general should be regarded as merely incidental to spectral illusions.

bingers of the paroxysm, there has not only been the well-known aura epileptica, but also a wild display of phantasms. A woman, whose case is related by Portius, was always warned of an approaching fit by the appearance of her own image in a mirror; and Sauvage mentions, that even during the paroxysm dreadful spectres have been seen. It is likewise a curious fact, that in such forms of the disease, real objects have occasionally seemed magnified to an extraordinary degree, while, among coloured substances, a green hue has predominated. Another form of Ecstasis is that which occasionally occurs as a symptom in catalepsy, where the influence of those nerves which are connected with voluntary muscles is so diminished, that the limbs are unable to resist external force, but yield to it with readiness, and retain any position in which they may be placed. I shall, lastly, observe, that a general state of nervous irritability not unfrequently exercises its influence on the system, in concurrence with a highly-excited condition of the sanguine or melancholic temperament. An increase of action here takes place in that extensive system of nerves, upon which the processess of assimilation depend. This effect is pointed out by the peculiar symptoms, which arise in the organs more immediately connected with digestion. “ From the centre of the epigastric region,” says Pinel, “ are propagated, as it were by a species of irradiation, the accession of insanity, when all the abdominal system even appears to enter into the sad confederacy. The patient complains of a sense of tightness in the region of the stomach, want of appetite, obstinate constipation, and a sensation of heat

in the bowels, which obtains a temporary relief from copious draughts of cooling liquids."-"This reaction of the epigastric region upon the functions of the understanding is so far from oppressing and obscuring them, that it appears even to augment their vivacity and strength. The imagination is exalted to the highest pitch of development and fecundity. Thoughts the most brilliant and ingenious, comparisons the most apt and luminous, give to the maniac an air of supernatural enthusiasm and inspiration. The recol. lection of the past appears to unroll with great rapidity, and what had long been not thought of and forgotten, is then presented to the mind in glowing and animated colours.”—In another place the same eloquent writer adds, “ Dreams of ecstacy, and visions of heavenly pleasure, are the ordinary preludes to paroxysms of maniacal devotion: as those of unfortunate love are preceded by similar interruptions of sound and healthful sleep. The beloved object appears under the form of an exquisite beauty, with every other advantage, greatly exaggerated by the magic power of fancy. But the too happy dreamer, after an interval of more or less continuance of reason and calmness, awakes once more the noisy, the disconsolate, and the furious maniac."*

* Pinel's Treatise on Insanity ; translation by D. D. Davis, M.D. pages 17 and 28.

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