Page:Popular Science Monthly Volume 85.djvu/574

570 higher mental processes, they are obscurely purposeful. So also are the impulsive acts of dementia præcox as compared with those of general paralysis.

The psychology of feeling is one in which the standpoint of individual differences has played very little part. The field is both tempting and difficult, and there has been the least progress in proportion to the experimental work done in mood and emotional reaction. Common observation shows that there are true individual differences, and for the adaptation to life, these differences are of paramount significance.

In many of the psychoses, the mood and emotional reactions are markedly and fundamentally altered. Heightened emotional sensitiveness, or lability of mood, is especially characteristic of exophthalmic goiter or Graves' disease. The source of intoxication here being internal secretion, it is a noteworthy illustration of the interdependence between mental activity and various extraneural processes. Functional atrophy of the thyroid gland is accompanied by a converse picture showing dulness and stupor, and with generally opposite symptoms, both physical and mental, to Graves' disease.

Still other psychoses are characterized by feelings of exaggerated well-being. The manic excitement shows a typically active exhilaration, often with no apparent diminution of intellect, manifesting itself as we should expect to see it manifested in an exaggeratedly happy normal person, with dancing, singing, jibing, half-jocular overestimations of one's powers and the like. Another phase of the manic-depressive psychosis shows a sort of mute transport, or silent ecstasy, in which it is very difficult to get at the mental content at all; it is termed the manic stupor. The most genuinely beatific state of mind that is maintained in terrestrial relations is probably seen in general paralysis; a state of easy-going, beaming euphoria, which the patient himself has no words to describe, but which finds some expression in grandiose but feeble delusions, scarcely if at all reacted to, as that he possesses countless millions, is king of the world, the super-god. It is interesting to note that this unitary disease process is associated with a great variety of mental pictures, sometimes with melancholic symptoms instead of the euphoria.

Simple, persistent depression of spirits is not a normal mental reaction to any external cause, but it is a most common reaction of the psychoses, where it is classified with the depressed phase of the manic-depressive group. This is the correlate of the manic condition above mentioned, sometimes alternating with it; though alone, it represents much the more benign process of the two. As in exhilaration, a number of delusions may arise secondarily to the emotional condition, which here favors depressive or persecutory interpretations of the events about one. These ideas are generally superficial and changeable; there is