The significance of coherency between EEG and EMG in motor control

我们研究了表现出显著皮质-肌肉相干性的受试者和表现不显著相干性的受试者的MU放电方式。我们比较了两类被试的皮质-肌肉一致性和皮质驱动与MU活动之间的一致性。研究表明，即使MU不构成时间集合，如分组放电，单个MU与皮质驱动是一致的。我们通过计算皮层驱动的瞬时相位分布对皮层驱动放电时间的圆方差，定量地评价了皮层驱动对皮层驱动相位的依赖性。我们发现，随着力水平的增加，MU逐渐被皮层驱动的节奏所困住。此外，通过使用皮质驱动相的ISIH，也证实了间歇性的MU放电。我们已经展示了锁相活动和MU间歇性放电的证据，并揭示了净神经肌肉活动和单个运动单元放电之间的因果关系。

We investigated the manner of MU discharge in both subjects who showed significant cortico-muscular coherence and subjects who showed non-significant coherence. We compared the two types of subjects about cortico-muscular coherence and coherence between cortical drive and MU activity. It has been shown that, even if MUs did not construct temporally ensemble such as grouped discharge, single MU was coherent with cortical drive. We evaluated dependency of MU on phase of cortical drive quantitatively by calculating circular variance of instantaneous phase distribution of cortical drive on MU firing timing. We found that MU was gradually being entrapped by the rhythm of the cortical drive as the level of force increased. Furthermore, by ISIH using phase of cortical drive, intermittent MU discharge has also demonstrated. We have shown the evidence of phase-locked activity and intermittent discharge of MU, and revealed the causal relationship between net neuromuscular activity and individual motor unit firing.