[The reactivity of the sensorimotor rhythm in patients with depressive disorders]

Reactions of mu-rhythm to sound (unspecific reactivity), actual and imaged movement (specific reactivity) were studied in 30 right-handed patients with psychogenic (Pg) and endogenous (Eg, cyclophrenia and low-progredient schizophrenia) subdepressive disorders and 23 healthy subjects. Predominant derangement of specific reactivity was revealed in patients which consisted in attenuation of reactions and reorganization of interhemispheric relations. During the actual movement there was a decrease in mu-rhythm reactivity in the left hemisphere and its increase in the right one. The imaged movement was associated with some decrease in the right-hemisphere mu-rhythm reactivity. The degree of reorganization of interhemispheric relations was higher in Eg patients, especially in schizophrenic ones. Abnormal ipsilateral reactions were induced by the actual (in Eg patients) or imaged movement (in Pg patients) with the right hand. These abnormal reactions are regarded as a return to an immature (childish) form. Only in schizophrenic patients the level of unspecific reactivity is lower than in the healthy subjects. There were no hemispheric differences in the sound-induced mu-rhythm reaction both in patients and healthy subjects.