USING ELECTROENCEPHALOGRAPHY TO STUDY FUNCTIONAL COUPLING BETWEEN CORTICAL ACTIVITY AND ELECTROMYOGRAMS DURING VOLUNTARY CONTRACTIONS IN HUMANS

Previous studies of neuronal oscillations in sensorimotor cortex in hu mans and primates have observed rhythmic 15-30 Hz activity, which is c orrelated with motor output. In humans, this work has been limited to magnetic recordings. In the present study we investigate if similar re sults can be obtained using electroencephalography (EEG). EEG recordin gs were made from over the sensorimotor cortex of five adult subjects who performed repeated periods of maintained wrist extension and flexi on. Coherence analysis between EEG and electromyogram (EMG.) recording s from these muscles revealed correlation in the 15-30 Hz range, with a synchronous correlation structure which matches that previously obse rved in humans and in paired cortical recordings from primates. We con clude that EEG is equally efficient at investigating functional aspect s of these cortical rhythms during voluntary movement in humans. (C) 1 998 Elsevier Science Ireland Ltd.