Cortical beta synchronization is related to low-order motor parameters

To study the possible functional role of event-related de-synchronization in the beta band we altered various motor parameters in order to challenge the level of synchronization. We recorded whole-head MEG, bilateral EMG, and force during a rhythmic motor task, in which participants had to produce isometric forces paced by acoustic stimuli. Movement rate, force level, and task difficulty (synchronization vs. syncopation) were manipulated and changes in synchronization were analyzed. The results indicated that beta amplitude was mainly affected by ‘low-order’ motor parameters, such as force level and movement rate.