[Intellectual activity at different stages of an episode of periodic schizophrenia].

In 44 patients with periodical forms of schizophrenia at different stages of the stereotypical acute attack, the authors performed experimental psychological tests in order to study different aspects of intellectual activity (attention, memory, special-constructive and semantic thinking). It was established that the development of attacks was accompanied by increasing disorders of voluntary attention. Depending upon the sign of dominating effects, disordered active attention was accompanied either by acceleration and lability, or by delayed and inert psychic processes. This leads to an increasing disturbances in the organization of all forms of intellectual activity, up to a total inhibition of active psychic reflection at the clinical phase of the attack. The supposition is made that these disorders are connected with the changes in the level of brain vigilance.