MENTALI, MALATTIE. – Morbid conditions also called frenopathies, psychopathies, psychoses, which manifest themselves in acute or chronic form through disturbances of psychic activities, both intellectual (noopsychic) and affective, instinctive, and sentimental (thymopsychic), when the brain is altered in its structure or impaired in its function by exogenous morbid causes (traumas, tumors, tox infections, endocrine disorders, emotions, etc.) or endogenous ones (degenerative, atavistic, hereditary); the latter, often producing a congenital debility and diminished resistance in the nervous centers, predispose the individual to the action of exogenous causes, so that the two types not infrequently interpenetrate and complement each other in the genesis of psychopathy.
As regards the causal value of emotions, a careful examination of the patient and of his antecedents always makes it possible to detect the preexistence of a psychopathic constitution or of the mental illness itself, already in progress for some time; consequently, the psychic trauma assumes the value of a revealing element or that of a contributing cause in the determination of a reactive psychosis arising on a constitutionally predisposed basis. The more intimate causes and the pathological anatomy of mental illnesses, with few exceptions, are uncertain and imprecise, and for some are entirely unknown; their classification reflects this uncertainty and varies greatly according to the concepts upheld by the different schools. In general, a first broad distinction is accepted between organic forms and functional forms, based on whether or not there exists a demonstrable anatomical alteration to account for their symptomatology.

The uncertainty of the causes and the consequent imprecision of the classification inevitably affect the treatment of psychoses, which, very often, particularly in the more obscure cases, is limited to a purely symptomatic level. On the other hand, it cannot be denied that, especially in recent years, notable progress has been made in treatment and significant results achieved through the recent shock methods (insulin, electrical, cardiazol, acetylcholine, etc.), chiefly in schizophrenia and dysthymias; with malariotherapy and insulin in progressive paralysis. With these methods of treatment, it is often possible, if not to achieve complete cures, to obtain such improvement as to allow many psychopathic patients formerly condemned inevitably to chronicity to be returned to their families and to society, even to gainful employment. The prognosis remains unfavorable for severe cases, resistant to every intervention, and for degenerative and involutional psychopathic conditions. In forms considered to have a functional basis, particularly the psychoneurotic forms (hysteria, psychasthenia, anxiety forms, neurasthenia or alarm syndrome, etc.) and wherever emotional psychological factors predominate, psychotherapy (v.), whether psychoanalytically oriented or not, narcoanalysis (v.), and prolonged sleep, recently introduced into therapy, are widely used, possibly in combination with drug treatments. Finally, the surgical treatment of psychopathy is very recent; through lobotomy, lobectomy, and topectomy, it isolates from their connections or even destroys more or less extensive regions of the cerebral cortex; it derives, with its applications developed and expanded, from the prefrontal leucotomy first performed by Moniz in 1936 and still in use. These operations are currently performed frequently, with varying results, in the treatment of obsessive psychosis, cyclothymias in general, schizophrenia, epilepsy, and post-encephalitic syndromes. No less important than treatment is the prophylaxis of mental illnesses, especially with regard to alcoholic psychoses and syphilis of the nervous system, carried out through suitable propaganda, outpatient examinations, and repeated medical and biological checks, with the aim of preventing and detecting psychopathy, particularly toxic and infectious psychopathy, in its initial phase, when treatment is more useful and arresting its development easier, whereas later it is irreparable.
As regards the state of intelligence, the modalities of character, and moral responsibility in mental illnesses, V. the respective entries, particularly the various « psychoses ».