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APOPLEXIES OR TUMOURS OR ARTERIAL DEG...
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APOPLEXIES OR TUMOURS OR ARTERIAL DEGENERATION . (a) Traumatic See also:Insanity.—Insanity following blows on the See also:head is divided into (I) the forms in which the insanity immedi- ately follows the See also:accident; (2) the See also:form in which there Traumatic innsanit is an intermediate prodromal See also:stage characterized by . See also:strange conduct and alteration in disposition; and (3) in which the See also:mental symptoms occur months or years after the accident, which can have at most but a remote pre-disposing causal relation to the insanity. The cases which immediately succeed injuries to the head are in all respects similar to confusional insanity after operations or after fevers. There is generally a noisy incoherent See also:delirium, accompanied by hallucinations of sight or of See also:hearing, and fleeting unsystematized delusions. The See also:physical symptoms See also:present all the features of severe See also:nervous See also:shock. In those cases in which there is an intervening prodromal See also:condition, with altered See also:character and disposition, there is usually a more or less severe accidental. implication of the cortex cerebri, either by depression of See also:bone or See also:local hemorrhage, or meningitic sub-inflammatory local lesions. Most of the cases during the prodromal stage are sullen, morose or suspicious, and indifferent to their See also:friends and surroundings. At the end of the prodromal stage there most usually occurs an attack of acute See also:mania of a furious impulsive See also:kind. The cases which for many years after injury are said to have remained sane will generally be found upon examination and inquiry to exhibit symptoms of hereditary degeneration or of acquired degeneracy, which may or may not be a consequence of the accident. The most See also:common site of vascular See also:lesion is one of the branches of the See also:middle cerebral artery within the sylvian fissure, or of one of the smaller branches of the same artery which go directly to See also:supply the See also:chief basal ganglia. When an artery like the middle cerebral or one of its branches becomes either through rupture or blocking of its lumen, incapable of performing its See also:function of supplying See also:nutrition to important cerebral areas, there ensues devitality of the nervous tissues, frequently followed by softening and chronic inflammation. It is these secondary changes which give rise to and maintain those See also:peculiar mental aberrations known as See also:post-apoplectic insanity. Various characteristic physical symptoms, depending upon the seat of the cerebral lesion, are met with in the course of this form of insanity. These consist of paraplegias, hemiplegias and See also:muscular contractures. Speech defects are very common, being due either to the enfeebled mental condition, to See also:paralysis of the See also:nerve supplying the muscles of the See also:face and See also:tongue,or to aphasia caused by implication of those parts of the cortex which are intimately associated with the See also:faculty of speech. Mental symptoms vary considerably in different cases and in accordance with the seat and extent of the lesion. There is almost always present, however, a certain degree of mental enfeeblement, accompanied by loss of memory and of See also:judgment, often by mental confusion. Another very See also:general mental symptom is the presence of emotionalism which leads the patient to be affected either to tears or to See also:laughter upon trifling and inadequate occasions. Cerebral tumours do not necessarily produce insanity. Indeed it has been computed that not one See also:half of the cases become insane. When insanity appears it is met with in all degrees varying from slight mental dulness up to See also:complete dementia, and from See also:mere moral perversion up to the most intense form of maniacal excitement. On the physical See also:side the various symptoms of cerebral See also:tumour such as Loma, ataxia, paralysis, headache, vomiting, optic See also:neuritis and epileptiform See also:convulsions are met with. All forms of so-called moral changes and of changes of disposition are met with as mental symptoms and all the See also:ordinary forms of insanity may occur in varying in-tensity; but by far the most common mental See also:change occurring in connexion with cerebral tumour is a progressive enfeeblement of the intelligence, unattended with any more harmful symptoms than mental deterioration which ends in complete dementia. (b) Arterial Degeneration.—Arterial degeneration is a common cause of mental impairment, especially of that form insanity of mental See also:affection known as " See also:Early " dementia. due to It also predisposes to embolism and thrombosis, Arterial which often results in the paralytic and aphasicDegeneragroups of nerve disturbance, and which are always See also:Don. accompanied by more or less marked interference with normal cerebral See also:action. The commonest seat for atheroma of the cerebral vessels is the See also:arteries at the See also:base of the See also:brain and their See also:main branches, especially the middle cerebral. As a general See also:rule the other arteries of the cerebrum are not implicated to the same extent, although in a not inconsiderable number of cases of the disease all the arteries of the brain may participate in the change. When this is so, we obtain those definite symptoms of slowly advancing dementia commencing in See also:late middle See also:life and ending in complete dementia before the usual See also:period for the See also:appearance of senile dementia. The same appearances are met within certain patients who have attained the See also:age in which senile changes in the arteries are not unexpected. As a rule atheroma in the cerebral vessels is but a See also:part of a general atheroma of all the arteries of the See also:body. Atheroma is common after middle life and increases in frequency with age. The chief causes are syphilis, alcoholism, the gouty and rheumatic diatheses and above all See also:Bright's disease of the kidneys. Perhaps certain forms of Bright's disease, owing to the tendency to raise the See also:blood pressure, are of all causes the most common. It is not easy to say to what extent, alone, the arteriosclerosis is effectual in inducing the See also:gradual failure of the mental See also:powers, and to what extent it is assisted in its operation by the action on the brain-cells of the general toxic substances which give rise to the arterial atheroma. In any See also:case there can be no question that the gradual See also:mechanical diminution of the blood-supply to the cortex caused by the occlusion of the lumen of the arteries is a See also:factor of See also:great importance in the See also:production of mental incapacity. Additional information and CommentsThere are no comments yet for this article.
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