CHAPTER IX. DEMENTIA. § 280. THIS form of insanity is attended by a general enfeeblement of the moral and intellectual faculties which were originally sound and well-developed, in consequence of age or disease, and is characterized by forgetfulness of the past, indifference to the present and future, and a certain childishness of disposition. The apparent similarity of this state to that of imbecility or idiocy, renders it necessary that they should be accurately distinguished; for nothing could be more improper or unjust, than to view them merely as different shades of the same mental condition. Idiocy and the higher degrees of imbecility are congenital or nearly so, and consist in a destitution of powers that were never possessed. Little or nothing is remembered, because little or nothing has left any impression upon the mind, and no advance is made in knowledge, because the faculties necessary for obtaining it have never existed. The proprieties and decencies of life are unobserved, for the simple reason that their moral relations have never been discerned, and their indifference to the most pressing wants is to be attributed to the absence of the most common instincts of our nature. The idiot is restless, uneasy, and inattentive, because the faculties that direct the attention, and draw from its application valuable results, have been utterly denied. In idiocy and imbecility the manners and conversation strongly resemble those of childhood; in dementia they never lose the impress of manhood, however disjointed and absurd they may be. The former appear at an early age of life; the latter never takes place till after the age of puberty, except occasionally as a sequel of wounds or diseases of the head, and generally increases with time, from the slightest possible impairment of mental energy to the most complete fatuity. In dementia the past is forgotten, or but indistinctly and unconnectedly brought up to the mind; the attention wanders from one thing to another; the affairs of the present possess no interest; and the moral and social affections are inactive, because the faculties, in consequence of pathological changes in the brain, have fallen into a state of inertia that prevents their ordinary manifestations. The whole condition betrays the existence, not of physical imperfection, but of physical weakness, (many of the bodily functions also frequently being enfeebled,) and consequently it may sometimes be cured, or temporarily relieved. When once firmly seated, it is not incompatible with length of years; and after death, we may find, on examination, lesions of structure, or diminutions of size, which are accidental, the result of diseased action, and not original malconformations. The above comparison of mental deficiency with dementia shows, that they depend on two very different conditions of the brain, and consequently must display very different moral and intellectual manifestations; from which we are warranted in inferring that in regard to their medico-legal relations, they cannot properly be placed on the same ground. § 281. Dementia is distinguished from general mania, the only other affection with which it is liable to be confounded, by characters that cannot mislead the least practised observer. The latter arises from an exaltation of vital power, from a morbid excess of activity, by which the cerebral functions are not only changed from their healthy condition, but are performed with unusual force and rapidity. The maniac is irrational from an inability to discern the ordinary characters and relations of things, amid the mass of ideas that crowd upon his mind in mingled confusion; while in dementia, the reasoning faculty is impaired by a loss of its original strength, whereby it not only mistakes the nature of things, but is unable, from want of power, to rise to the contemplation of general truths. The reasoning of the maniac does not so much fail in the force and logic of its arguments, as in the incorrectness of its assumptions; but in dementia the attempt to reason is prevented by the paucity of ideas, and that feebleness of the perceptive powers, in consequence of which they do not faithfully represent the impressions received from without. In mania, when the memory fails, it is because new ideas have crowded into the mind, and are mingled up and confounded with the past; in dementia the same effect is produced by an obliteration of past impressions as soon as they are made, from a want of sufficient power to retain them. In the former, the mental operations are characterized by hurry and confusion; in the latter, by extreme slowness and frequent apparent suspension of the thinking process. In the former, the habits and affections undergo a great change, the conduct becoming strange and inconsistent from the beginning, and the persons and things that once pleased and interested, viewed with indifference or aversion. In the latter, the moral habits and natural feelings, so far as they are manifested at all, lose none of their ordinary character. The temper may be more irritable, but the moral disposition evinces none of that perversity which characterizes mania. § 282. In dementia the mind is susceptible of only feeble and transitory impressions, and manifests but little reflection even upon these. They come and go without leaving any trace of their presence behind them. The attention is incapable of more than a momentary effort, one idea succeeding another with but little connection or coherence. The mind has lost the power of comparison, and abstract ideas are utterly beyond its grasp. The memory is peculiarly weak, events the most recent and most nearly connected with the individual being rapidly forgotten. The language of the demented is not only incoherent, but they are much inclined to repeat insulated words and phrases without the slightest meaning. "It seems," says Esquirol, "as if they were listening to imaginary tales which they repeat in obedience to an involuntary or automatic impulse excited by their old habits or fortuitous associations with actual impressions." 1 1 Maladies Mentales, ii. 220. The mind is often occupied by hallucinations which continue a longer or shorter time, and disappear to be succeeded by others. The useful or ornamental arts which they may have practised with skill and followed with ardor, and the various other employments of life, seem to be utterly forgotten as if they had never been thought of. Their time is spent either in moving about with restless activity, or passing days, weeks, or months, in the same spot, in utter vacuity of thought or purpose; in pouring forth an incessant flow of words at the top of their voice, or uttering low, muttering sounds, consisting of scarcely articulate words and broken phrases; in singing, crying, or laughing.. § 283. Though often irascible and self-willed, their anger is momentary, and thus they readily yield to the direction of others. The moral powers, in fact, seem to be possessed of too little energy to maintain resolution, or cherish the passions. Their feebleness of purpose and passive obedience to the will of others, strikingly contrast with the pertinacity and savage fury often evinced by the maniac. With the remembrance of their friends and former employments, there also disappears all trace of the social and domestic affections. All interest in the concerns of others is lost; and family, friends, and relations are viewed with the indifference of perfect strangers, and nothing is able to awaken an emotion of pleasure or pain. § 284. The derangement of the intellectual powers is sometimes indicated by remarkable changes of the countenance. The skin is pale, dry, and wrinkled; the eyes sunken, dull, and moistened with tears; the pupils dilated; the look uncertain and wandering; the cheeks hollow and emaciated; and the whole face destitute of expression, and indicative of decay. The organic functions suffer but little; the appetite for food is so great that the patient seems to be constantly eating, and the quantity consumed is enormous. Affections of the nervous system, however, particularly paralysis, are not unfrequent complications of dementia. 285. The above description is applicable to dementia only when fully developed and before it has passed into the state of fatuity in which it often terminates. This form of insanity appears under two different degrees of severity, which are designated as acute and chronic. The former is a sequel of temporary errors of regimen, of fevers, hemorrhages, metastases, suppression of customary evacuations, and the debilitating treatment of mania. It differs from the latter in being more rapid in its progress, and in its successive stages not being so well distinguished from one another. It is readily cured by regimen, exercise, bathing, tonics, antispasmodics, or simply by removing the exciting cause. It sometimes terminates in an explosion of acute mania, which then becomes critical. § 286. Chronic dementia is a sequel of mania (of which it is the usual termination) when life continues long enough, of apoplexy, epilepsy, masturbation, and drunkenness; or it may occur idiopathically, and then it usually accompanies old age. This form of the disorder, or senile dementia, is so often the subject of medico-legal inquiries, especially in connection with wills, that it deserves particular attention. Senile · dementia, it must be recollected, is something more than that mere loss of mental power which results from the natural decay of the faculties; it is attended with those pathological changes also which are essential to the production of insanity. The mind is not only feeble, but it is deranged. Were it not so, every old man would labor under a certain degree of dementia. The first symptom which indicates the approach of this affection, is generally an impairment of the memory of recent occurrences. The events of early life have lost none of their distinctness, while recent impressions are feebly made, and in a short time mostly forgotten. While the visits of his friends are forgotten beyond the day or week they are made, the patient may talk of their former interviews, and relate the most trivial details concerning them. From this weakness of memory seems to arise, oftentimes, the first appearance of mental alienation. The patient forgetting the intermediate ideas, the connection between those he does remember, and that order and filiation of them necessary to sound reasoning, are destroyed; and hence those |