G. Pfurtscheller et al., EVENT-RELATED BETA-SYNCHRONIZATION AFTER WRIST, FINGER AND THUMB MOVEMENT, ELECTROMYOGRAPHY AND MOTOR CONTROL-ELECTROENCEPHALOGRAPHY AND CLINICAL NEUROPHYSIOLOGY, 109(2), 1998, pp. 154-160
Pre-movement event-related desynchronization (ERD) and post-movement e
vent-related synchronization (ERS) were studied in a group of normal s
ubjects during voluntary thumb, index finger and wrist movement. The b
and power time courses were computed for the upper alpha band (10-12 H
z) and for two frequency bands in the range of beta (16-20 Hz and 20-2
4 Hz). While a similar mu ERD was found during motor preparation for t
he 3 movement tasks, significant differences concerning beta synchroni
zation were observed after movement off set. The contralateral percent
age beta increase (ERS) was significantly larger in gross movements of
the wrist as compared to index finger and thumb movements, which is d
iscussed under the assumption of a cumulative effect. Summarizing, pre
-movement desynchronization seems relatively independent of the forthc
oming type of movement, whereas the post-movement beta synchronization
might depend on the activated muscle mass. (C) 1998 Elsevier Science
Ireland Ltd.