At present, the essence of psychoses is not understood fully. In the 20th century, thanks to progress in such fields as genetics, molecular genetics, neuroimmunology, neurochemistry, physiology, i.e. the whole complex of neurosciences, many mechanisms of development of such states as depression, anxiety, fear, agitation became more understandable. It became possible to diagnose DNA (DNA-diagnostics) exactly; when a number of diseases manifest (Huntington's chorea, Down's disease, and other differentiated oligophrenias). Such a break-through in science became particularly obvious in the last decade of the twentieth century; this decade was designated as 'Brain decade' by the World Health Organisation (WHO). By the early 21st century, a human genome had been decoded, and scientists got anatomy genetics onto their hands. This gives us a possibility to look into the future of psychiatry with optimism because it is receiving the status of an exact science. In this regard, it would be expedient to present the most important of the fundamental scientific data of biology directly related to psychiatry.
AETIOLOGY AND PATHOGENESIS OF MENTAL DISORDERS
Studying medical records, the psychiatrist working in a clinic regularly examines the presence of various mental factors that are involved in the development of the pathological process. P.J. Moebius (1893) was the first to propose to divide all causes of psychoses into external (exogenous) and internal (endogenous). Following such dichotomy, mental disorders themselves are divided into exogenous and endogenous.
Among the internal (endogenous) causes of disease, genetic factors, there are ones of special importance such as developmental disorders in the early age, the somatic diseases that complicate and worsen brain functions due to ischemia, autointoxication, and endocrinopathy.