Page:Popular Science Monthly Volume 85.djvu/578

574. It has rather the appearance of a selective action of the drug upon particular nervous elements. The hallucinations of delirium tremens are typical of this. Epilepsy is said to favor hallucinations of blood, fire, and catastrophe; cocaine, images of a microscopic character. Detailed analyses are apt to be unsatisfactory, owing to the unclear condition of the patient; when the alcoholic reads from or describes in detail the picture on a blank page, he confabulates rather than hallucinates. A number of curious clinical observations, such as illusory completion of lost fields in hemianopsia, doubled hallucinations to prisms or pressure, made greater or smaller by opera-glasses, hallucinations in one eye or ear only, need be no more than mentioned.

Hallucinations are reported in all the major psychoses, but for the understanding of the clinical picture, they, and the delusional ideas which supplement them, play the most important role in those types of mental disorder which have been termed biogenetic; that is, where the personality as such fails to meet the normal mental demands of the environment, and reacts to it along certain fairly definite pathological lines. These types of reaction may be for us summed up in the manic-depressive and dementia præcox groups. A most significant development in the conception of these conditions is that their basic hallucinations and the delusions, whether or not involved with them, are the expressions, not of the selective action of some fortuitous intoxication, but of instinct trends, detached from, or not controlled by, the main personality, and lived out through fantasy. Both Tuttle from the pathological and Cattell from the normal side have indicated how ideas can develop into hallucinations through abnormal reaction to them. These hallucinations and delusions are thus absolutely continuous with normal imagery and imagination, and the minor satisfactions which these latter supply to the normal individual are here magnified to take the place of reality, in response to coercive instincts and desires for whose adjustment reality must be escaped. Are some patients beset by unrecognized erotic longings? The voices horrify them with accusations of immorality. Is there some obscure maladaptation in the patient's marriage? The response may be a tragic imagination of the partner's death. The husband who visits his wife is then not her husband, but an impostor. Or there may be a fancied alteration of personality, as when under similar circumstances a young man calls himself at different times "Harry Thaw," "Clarence Richeson," the "king of the fairies."

Following Cattell's formulation of those higher mental qualities not directly measurable, we should say that defects, particularly of judgment, lead to the most serious consequences in general paralysis, arteriosclerosis, and sometimes in manic excitement. Refinement deteriorates especially in dementia præcox and in general paralysis, being, however,