Department of Clinical and Movement Neuroscience, UCL Queen Square Institute of Neurology, London, United Kingdom.
Department of Neurology, University of San Francisco, California, United States of America.
PLoS Biol. 2019 Oct 4;17(10):e3000479. doi: 10.1371/journal.pbio.3000479. eCollection 2019 Oct.
Motor cortical beta activity (13-30 Hz) is a hallmark signature of healthy and pathological movement, but its behavioural relevance remains unclear. Using high-precision magnetoencephalography (MEG), we show that during the classical event-related desynchronisation (ERD) and event-related synchronisation (ERS) periods, motor cortical beta activity in individual trials (n > 12,000) is dominated by high amplitude, transient, and infrequent bursts. Beta burst probability closely matched the trial-averaged beta amplitude in both the pre- and post-movement periods, but individual bursts were spatially more focal than the classical ERS peak. Furthermore, prior to movement (ERD period), beta burst timing was related to the degree of motor preparation, with later bursts resulting in delayed response times. Following movement (ERS period), the first beta burst was delayed by approximately 100 milliseconds when an incorrect response was made. Overall, beta burst timing was a stronger predictor of single trial behaviour than beta burst rate or single trial beta amplitude. This transient nature of motor cortical beta provides new constraints for theories of its role in information processing within and across cortical circuits, and its functional relevance for behaviour in both healthy and pathological movement.
运动皮质β活动（13-30 Hz）是健康和病理运动的标志性特征，但它的行为相关性尚不清楚。使用高精度脑磁图（MEG），我们表明在经典事件相关去同步（ERD）和事件相关同步（ERS）期间，个体试验中的运动皮质β活动（n > 12,000）由高振幅、瞬态和罕见的爆发主导。β爆发概率在运动前后的试验平均β振幅中非常匹配，但单个爆发的空间焦点比经典 ERS 峰值更集中。此外，在运动前（ERD 期间），β爆发的时间与运动准备的程度有关，较晚的爆发导致反应时间延迟。运动后（ERS 期间），当做出错误反应时，第一个β爆发会延迟约 100 毫秒。总体而言，β爆发时间比β爆发率或单个试验β振幅更能预测单个试验行为。这种运动皮质β的瞬态性质为其在皮质回路内和跨皮质回路中的信息处理中的作用理论提供了新的限制，并且对健康和病理运动中的行为具有功能相关性。
