[Functional asymmetry of the cerebral hemispheres during visual perception in schizophrenics with productive and negative symptoms].

To study the characteristics of the interhemispherical interaction, tachistoscopic unilateral presentation of verbal stimuli (letters) was used. Three groups of patients were examined: 27 schizophrenic patients with symptoms of an emotional-volitional defect; 23 with the syndrome of psychic automatism in the framework of schizophrenia, and 20 mentally normal subjects. Subjects from different groups presented significant differences in the nature of recognition of stimuli addressed to the right or left hemisphere. These differences are considered from the standpoint of impairment of the interhemispherical interaction in schizophrenia, which is in agreement with the existing model ideas about the visual recognition through the combined work of both brain hemispheres and relative functional specialization of each of them. To explain a possible link of the defect of the interhemispherical interaction and psychopathological symptomatology in schizophrenia, a hypothesis is advanced according to which this defect leads to changes in the time structure of reflection serving as a form of correlation between the immediately percepted things and the past experience of the patients.