Insanity

(in-săn'e-te.) (From L. in san it as, unsoundne .] (Med.) A general term under which are included all the varieties of unsound mind-Mania, Melancholia, Moral Insanity, Dementia, and Idiocy. The prevailing view of physiologists is, that I. is a symptom or expre ion, manifested through the functions of the nervous system, of physical disease. Thus, at a meeting of the British A ociation for the Advancement of Science, held in 1871, Dr. T. B. Tuko read a paper in which he stated: " It is generally acknowledged that the intellectual powers are manifested through the gray matter of the cerebrum; and as in 1. these faculties were impaired, exaggerated, or perverted, I believe that, by examining the brains of the insane, a hope exists of discovering a road for arriving at the solution of the functional difficulty. The time has pa ed when the terms mental disease, I., or madne , conveyed to the minds of physicians the idea that the mind or its faculties were the entities which were the subject of disease. By a proce of reasoning, the pathologist has arrived at the conclusion that the abnormal physical manifestations are dependent upon primary or secondary changes in the nervine ti ue; that 1. is a symptom of disease, not a disease in itself, and that the cause of the disease must be looked for in the brain. Six years ago, I commenced a systematic microscopic examination of the brains of the insane, and with this most important result, that in every single instance a marked departure from healthy structure was observed." -(Law.) In medical jurisprudence, the term I. has been, of late years, used to designate all mental impairments and deficiencies formerly embraced in the terms lunacy, idiocy, and unsoundne of mind. I. is defined to be the prolonged departure, without any adequate cause, from the states of feeling and modes of thinking usual to the individual when in health. I., in some of its forms, and when proved beyond a reasonable doubt, annuls all criminal responsibility, and, in the same and other forms, disqualifies its subject from the performance of certain civil acts. [s. 486]