Functional mapping of human sensorimotor cortex with electrocorticographic spectral analysis. I. Alpha and beta event-related desynchronization

Lack of bilateral coherence of post-movement central beta oscillations in the human electroencephalogram

Voluntary finger movement results in attenuation or desynchronization of the Rolandic mu and central beta rhythms some seconds before movement, followed by a post-movement synchronization of the central beta activity (post-movement beta synchronization). Although it has been demonstrated that the Rolandic mu rhythms show a lack of bilateral coherence, the coherence between post-movement central beta oscillations over left and right hemispheres has, as yet, not been investigated. In this study, post-movement changes in central beta activity over left and right sensorimotor hand areas are investigated in 13 healthy subjects by calculation of event-related coherence (ERCoh). The ERCoh time course allows the investigation of linear phase-coupling before, during and after voluntary movement. It is shown that no interhemispheric coherence exists between post-movement beta oscillations.