REACTIVITY OF THE SENSORIMOTOR RHYTHM IN SUBDEPRESSIVE PATIENTS

Reactions of mu-rhythm to sound (unspecific reactivity), actual and im aged movement (specific reactivity) were studied in 30 right-handed pa tients with psychogenous (Pg) and endogenous (Eg, cyclophrenia and low -progredient schizophrenia) subdepressive disorders and 23 healthy sub jects. Predominant derangement of specific reactivity was revealed in patients which consisted in attenuation of reactions and reorganizatio n of interhemispheric relations. During the actual movement there was a decrease in mu-rhythm reactivity in the left hemishere and its incre ase in the right one. The imaged movement was associated with some dec rease in the right-hemisphere mu-rhythm reactivity. The degree of reor ganization of interhemispheric relations was higher in Eg patients, es pecially in schizophrenic ones. Abnormal ipsilateral reactions were in duced by the actual (in Eg patients) or imaged movement (in Pg patient s) with the right hand. These abnormal reactions are regarded as a ret urn 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.