title: Event-related desynchronisation of central beta-rhythms during brisk and slow self-paced finger movements of dominant and nondominant hand.
abstract: Changes in central beta-rhythms (14-29 Hz) during movement were investigated in 12 right-handed subjects by quantifying event-related desynchronisation (ERD). EEG was recorded from 24 closely spaced electrodes overlaying the left and right sensorimotor hand area. The subjects performed approximately 80 brisk (movement time < 0.21 s) and 80 slow (movement time 1.3-2.1 s) self-paced extensions of their left or right index finger. Beta-band power attenuation in the preparatory period (2.0-0.5 s before movement onset) was larger in the contralateral hemisphere in both types of movement and similar for both fingers. In the 0.4-s period before the onset of extensor muscle contraction, right-finger movements only showed a significant contralateral preponderance of beta-ERD. During movement an anterior ERD predominance in the right sensorimotor hand area and a widespread ERD in the left sensorimotor area was found for both fingers. The recovery and rebound of beta-rhythms showed contralateral preponderance which was expressed more in the right hemisphere, especially after left-finger movements. The results suggest that the dynamics of premovement desynchronisation and postmovement synchronisation of central beta-rhythms is related to hand dominance.
authors.affiliation: Ludwig Boltzmann-Institute for Medical Informatics and Neuroinformatics, University of Technology, Graz, Austria. stancak@dpmi.tu- graz.ac.at
authors.forename: A
authors.initials: A
authors.lastname: Stancák
authors.forename: G
authors.initials: G
authors.lastname: Pfurtscheller
mesh_terms: D000328:Adult; D001611:Beta Rhythm; D003344:Cortical Synchronization; D004569:Electroencephalography; D004576:Electromyography; D005260:Female; D005385:Fingers / Q000502:physiology*; D007839:Functional Laterality / Q000502:physiology; D006225:Hand / Q000502:physiology*; D006801:Humans; D008297:Male; D009068:Movement / Q000502:physiology*