seminate useful and accurate knowledge in regard to the real nature of mental illness, so that the patient or his family will seek medical advice about his symptoms when they first appear and are mild, but no less ominous, rather than because of ignorance, shame or fear of hospital treatment and legal proceedings allow the disorder to progress to a more advanced stage, with the inevitable increase in the severity of the symptoms which too often makes the proceedings in law expedient and necessary.

CHAPTER IV

CAUSES-GENERAL CLASSIFICATION OF MENTAL

DISEASES

For ages mental disease was acknowledged to be the most mysterious of all the ills with which mortals were afflicted. The manifestations of acute mental disturbance were at times so sudden and unexpected, and so independent of any physical indisposition, their causes were beyond reason to explain, except that demons had entered into the human frame and taken possession of it, or that witches with supernatural power controlled the behavior, making it diabolical and fiendish. This lack of definite knowledge helped to create a fund of tradition, superstition and prejudice which unfortunately has persisted in various forms almost to the present day. The advances made through medical research and the scientific study of mental disorders have enabled the psychiatrist to know definitely the direct, specific and unmistakable causes of certain types or groups of mental disease, to know also the course which they are likely to take, in how far they will yield to treatment, and the means by which they may be prevented.

According to the etiology, mental diseases may be divided into the following groups: The organic psychoses, the toxic psychoses, psychoses with somatic diseases, and the constitutional psychoses.

1. The organic group includes those morbid conditions of the mind which are the result of actual changes in the structure of the brain, — the cells or their fibres, the membranes, or the blood vessels - changes which interfere with the function and produce a derangement of its normal action. In old age or senility, definite changes occur in the cells of the brain which tend to produce a diminution and

loss of mental action. With advancing years the blood vessels of the cerebrum frequently become sclerotic, a condition which not only tends to diminish the supply of blood necessary for normal function, but also causes a weakening of the arterial wall so that it cannot as well bear the high pressure of the blood within, and rupture of the vessel sometimes occurs with varying degrees of damage. Injuries to the cranium produced by physical violence, especially those of fracture and the consequent injury to the deeper structures, and tumors of the brain are other known causes of organic brain disease. Syphilis, an infectious disease of virulent nature, frequently attacks the nervous system and brings about destructive changes in the membranes and cortex which are progressive and fatal. In one of the largest of the New York State Hospitals, 25 per cent. of all the men admitted in the last few years have been diagnosed as paresis, a disease of syphilitic origin, and in the same hospital 47 per cent. of all the deaths for the year 1918 were due to the same cause. It is obviously one of the foremost causes in the production of mental disease.

2. The toxic group includes those forms of mental disease which are caused by toxins or poisons. These may be divided into the exogenous toxins - those produced by external agents, and the endogenous toxins those which originate within the body, or auto-toxins. Chief among the exogenous toxins is alcohol which because of its very general use has been a frequent factor in the causation of mental disease. Alcohol is a poison to the nervous system, even when taken in small quantities; but when taken habitually in quantities so moderate as not to produce intoxication, it diminishes the mental capacity and gradually produces irreparable ravages in the brain tissue, which eventually result in definite impairment and enfeeblement of mental power with loss of efficiency and economic waste. For some years prior to the World War and national prohibition alcohol was the chief etiological factor of the psychoses in from 8 to 10 per cent. of the patients admitted to

the New York State Hospitals. Other external agents are cocaine and opium and their derivatives and preparations and the coal tar products so commonly employed in headache remedies, hypnotics and anodynes.

The psychoses which are caused by endogenous toxins are associated with those physical diseases which occur because of the increased or diminished activity of glands upon which the integrity and health of the nervous system depend. Among these are hyperthyroidism, uræmia and diabetes.

3. The somatic disease group includes the mental disorders which are caused by the toxins produced by the microorganisms of the infectious diseases which are spoken of as the infective psychoses, and a second division of this group includes the exhaustive psychoses which are brought about by severe and prolonged illness, long-continued fatigue and privation-conditions which tend to diminish and deplete the vital and nervous power.

4. The constitutional group includes the very large number of mental diseases which are usually spoken of as "functional," diseases in which there are various symptoms of mental derangement, and yet the pathologist does not find changes in the structure of the nervous system which can explain these symptoms. The functional mental diseases occur for the most part in individuals who by nature or nurture have failed to receive those stabilizing qualities which enable one to unlearn and learn anew to adjust and adapt one's life to the changes and conditions which must be met in the course of human life and the march of progress. These individuals seem to be more than ordinarily vulnerable to the upsetting factors in their lives and mental disorders of various kinds are produced. Some of the precipitating factors of these psychoses are: The strain of close application to work, the stress of contest in the hustle of their daily lives, worry, jealousy, disappointment, grief, fatigue, misfortune, sudden shock, fright, isolation, unrelieved monotony, and certain vague longings and cravings which are insistent and insatiable.