Delirium, artificial.—The most common of these forms of disordered mental action is that transient and artificial state produced by intoxicating drugs and drinks. This is properly called delirium, and takes place whenever total or even partial inebriation occurs, whether from alcoholic or narcotic stimulants, as the opium of the Chinese, and the Indian hemp or hachish of the Hindoos. The same effects, substantially, are produced, also, by certain plants, as the deadly night-shade and others, and also by aconite. In all these cases the effect is wrought primarily, it would seem, upon the blood, which is brought into a poisonous state, and thus deranges the action of the nerves and the brain. The hachish or Indian hemp, which, in the East, is used for purposes of intoxication more generally, perhaps, than even opium, or alcoholic drinks, may serve as an illustration of the manner in which these various stimulants affect the senses. At first the subject perceives an increased activity of mind; thoughts come and go in swift succession and pleasing variety; the imagination is active—memory, fancy, reason, all awake. Gradually this mental activity increases and frees itself from voluntary control; attention to any special subject becomes difficult or even impossible; ideas, strange and wonderful, come and go at random with no apparent cause and by no known law of suggestion; these absorb the attention until the mind is at last given up to them, and there is no further consciousness of the external things, while, at the same time, the patient is susceptible, as in the magnetic state, of influence and impression from without. How closely, in many respects, this resembles the state of the mind in somnambulism, mesmerism, and ordinary dreaming, I need not point out. The mental excitement produced by opium is perhaps greater, and the images that throng the brain, and assume the semblance of reality, are more numerous and real. The subsequent exhaustion and reaction in either case are fearful. For illustration of this the reader is referred to the Confessions of an Opium Eater, by the accomplished De Quincey.
Delirium of Disease.—The ordinary delirium of disease is essentially of the same nature with that now described, differing rather in its origin, or producing cause, than in its effects. It comes on often in much the same way; increased mental activity shows itself; attention is fixed with difficulty; strange images, and trains of thought at once singular and uncontrolled by the will, come and go; the mind at last is possessed by them and loses all control over its own movements. Every thing now, which the mind conceives, assumes the form of reality. It has no longer conceptions but perceptions. Figures move along the walls and occupy the room. They are as really seen, that is, the sensation is the same, as in any case of healthy and actual vision; only the effect is wrought from within outward, from the sensorium to the optic nerve and retina, instead of the reverse, as in actual vision. Voices are heard also, and various sounds, in the same manner; the producing cause acting from within outward, and not from without inward.
Differs from Dreaming.—This state differs from dreaming in that the subject is not necessarily asleep, and that it involves a greater and more serious disorder of the faculties, as well as of longer continuance. The illusions are perhaps also more decided, and more vividly conceived as external and real entities. Like dreams, and unlike the conceptions of the magnetic state, these ideas and illusions may be subsequently recalled, and in many cases are so; the mind, however, finding it difficult still to believe that they were fictions, and not actual occurrences.
In dreaming, the things which we seem to see and hear are changes produced in the sensorium by cerebral or other influences. In delirium, the sensorium itself is disordered and produces false appearances, spectres, etc.
Mania.—That form of disordered mental action termed mania, differs from that already described in that, along with the derangement of the intellect, there is more or less emotional disorder. The patient is strongly excited on any thing that at all rouses the feelings. There may be much or little intellectual derangement accompanying this excitement. The two forms, in fact, pass into each by a succession of almost indefinable links. The main element is the same in each, i. e., loss of voluntary control over the thoughts and feelings. Each is produced by physical causes, and is of transient duration.
Power of Suggestion.—In all these forms of delirium now described, whether artificial or natural, the mind is open to suggestions from without, and these become often controlling ideas. Hence it is of imperative necessity that the attendant should be on his guard as to what he says or does in the presence of the patient. An instance in point is related by Dr. Carpenter, in which a certain eminent physician lost a number of his patients in fever by their jumping from the window, a fact accounted for at once, when we come to hear that he was stupid enough to caution the attendants, in the hearing of his patients, against the possibility of such an event.
II. Permanent Forms.—I proceed next to notice those more permanent forms of mental disorder, commonly termed insanity, a term properly applied to designate those cases of abnormal mental activity in which there seems to be either some settled disorder of the intellect, as, e. g., when the brain has been weakened by successive attacks of mania, epilepsy, etc., or else some permanent tendency to disordered emotional excitement.
Disorder of the Intellect.—Where the intellectual faculties are disordered, the chief elementary feature of the case is the same as in those already noticed, viz., Loss of voluntary control over the mental operations—the psychological ground-work, as we have seen, of all the various forms of abnormal mental action which have as yet come under our notice.
Memory affected.—In the cases now under consideration, the memory is the faculty that in most cases gives the first signs of failure, particularly that form of memory which is strictly voluntary, viz., recollection. In consequence of this, past experience is placed out of reach, cannot be made available, and therefore reasoning and judgment are deficient. The thoughts lose their coherency and connection, as they are thus cut loose from the fixtures of the past, to which the laws of association no longer bind them; they come and go with a strange automatic sort of movement, over which the mind feels that it has little power. Gradually this little fades away; the will no longer exercises its former and rightful control over the mental activities; its sway is broken, its authority gone; the mind loses control of itself, and, like a vessel broken from her moorings, swings sadly and hopelessly away into the swift stream of settled insanity. The mind still retains its full measure of activity, perhaps greatly increased; but it acts as in a dream. All its conceptions are realities to it, and the actually real world, as it mingles with the dream and shapes it, is but vaguely and imperfectly apprehended through the confused media of the mind's own conceptions. All this may be, and often is, realized, where there is entire absence of all emotional excitement.
Not easily cured.—The condition now described is much less open to medical treatment than the mental states previously mentioned. Indeed, where there is insanity resulting from settled cerebral disorder, there is very little hope of cure. Nature may in time recover herself; she may not. This depends on age, constitution, predisposing causes, and a variety of circumstances not altogether under human control.