Functional magnetic resonance imaging for exogenous and endogenous psychoses. A literature review

Psychosis is a syndrome that is non-specific for a particular disease, manifested by the production of the psyche in the form of delusions and/or hallucinations. Psychosis can be endogenous and exogenous in nature. The basis of endogenous psychotic disorders are diseases of the schizophrenia spectrum. External influence, including the use of psychoactive substances, is necessary for inducing exogenous psychosis. Recently, there has been an increase in research in psychiatry and narcology using functional magnetic resonance imaging. These studies were made possible by fMRI assessment modes: at rest and during task performance. Using these modes, it was possible to identify the interaction of remote brain regions and isolate individual functional neural networks. Studies of comparative characteristics of exogenous and endogenous psychoses are limited. The issue of the state of activity of brain structures during the manifestation of endogenous psychoses provoked by the use of psychoactive substances remains virtually unstudied. Identification of neuroimaging markers of such psychoses can clarify their differential diagnosis with exogenous ones and justify the need for preventive treatment strategies. The first years after the manifestation of endogenous psychosis represent a critical period when early intervention strategies can be most effective, before irreversible brain changes occur. Effective treatment after the first episode of psychosis not only improves functioning, but can actually change the trajectory of the disease, directing patients on the path to recovery.