Faculty of Sport and Health Sciences, University of Jyväskylä, Jyväskylä, Finland.
Department of Neuroscience and Biomedical Engineering, Aalto University School of Science, Espoo, Finland.
J Neurophysiol. 2020 Dec 1;124(6):1959-1967. doi: 10.1152/jn.00562.2020. Epub 2020 Oct 28.
Corticokinematic coherence (CKC) is the phase coupling between limb kinematics and cortical neurophysiological signals, reflecting cortical processing of proprioceptive afference, and it is reproducible when estimated with magnetoencephalography (MEG). However, feasibility and reproducibility of CKC based on electroencephalography (EEG) is still unclear and is the primary object of the present report. Thirteen healthy right-handed volunteers (seven females, 21.7 ± 4.3 yr) participated in two combined MEG/EEG sessions 12.6 ± 1.3 mo apart. Participants' dominant and nondominant index finger was continuously moved at 3 Hz for 4 min separately using a pneumatic-movement actuator. Coherence was computed between finger acceleration and three derivations of EEG signals: ) average reference, ) bipolar derivations, and ) surface Laplacian. CKC strength was defined as the peak coherence value at movement frequency. Intraclass-correlation coefficient values (0.74-0.93) indicated excellent intersession reproducibility for CKC strength for all derivations and moved fingers. CKC strength obtained with EEG was approximately two times lower compared with MEG, but the values were positively correlated across the participants. CKC strength was significantly ( < 0.01) higher for bipolar (: 0.19 ± 0.09; : 0.20 ± 0.10) and surface Laplacian (: 0.22 ± 0.09; : 0.21 ± 0.09) derivations than for the average reference (: 0.10 ± 0.04; : 0.11 ± 0.05). We demonstrated that CKC is a feasible and reproducible tool to monitor proprioception using EEG recordings, although the strength of CKC was twice lower for EEG compared with MEG. Laplacian and bipolar (CP3-C1/CP3-C3 and CP4-C2/C4-FC2) EEG derivation(s) are recommended for future research and clinical use of CKC method. The most important message in this report is that the corticokinematic coherence (CKC) method is a feasible and reproducible tool to quantify, map, and follow cortical proprioceptive ("the movement sense") processing using EEG that is more widely available for CKC recordings than previously used magnetoencephalography designs, in basic research, but especially in clinical environments. We provide useful recommendations for optimal EEG derivations for cost-effective experimental designs, making it possible to scale up in sample size in future studies.
皮质运动相干性（CKC）是肢体运动学和皮质神经生理信号之间的相位耦合，反映了皮质对本体感觉传入的处理，并且当使用脑磁图（MEG）进行估计时，它是可重现的。然而，基于脑电图（EEG）的 CKC 的可行性和可重复性尚不清楚，这是本报告的主要目的。13 名健康的右利手志愿者（7 名女性，21.7±4.3 岁）参加了两次相隔 12.6±1.3 个月的联合 MEG/EEG 会议。参与者的主导和非主导食指分别使用气动运动致动器以 3 Hz 的频率连续移动 4 分钟。在三个 EEG 信号的导数之间计算了相干性：）平均参考，）双极导数，和）表面拉普拉斯。CKC 强度被定义为运动频率处的最大相干值。组内相关系数值（0.74-0.93）表明，对于所有导数和移动手指，CKC 强度的两次会话之间具有极好的可重复性。与 MEG 相比，EEG 获得的 CKC 强度大约低两倍，但参与者之间的数值呈正相关。双极（：0.19±0.09；：0.20±0.10）和表面拉普拉斯（：0.22±0.09；：0.21±0.09）导数的 CKC 强度显著（<0.01）高于平均参考（：0.10±0.04；：0.11±0.05）。我们证明了 CKC 是一种使用 EEG 记录监测本体感觉的可行且可重复的工具，尽管与 MEG 相比，EEG 的 CKC 强度要低两倍。建议在未来的研究和 CKC 方法的临床应用中，使用 Laplacian 和双极（CP3-C1/CP3-C3 和 CP4-C2/C4-FC2）EEG 导数。本报告的最重要信息是，皮质运动相干性（CKC）方法是一种可行且可重复的工具，可使用 EEG 对皮质本体感觉（“运动感”）进行量化、映射和跟踪，与以前使用的脑磁图设计相比，EEG 更广泛地用于 CKC 记录，在基础研究中，但特别是在临床环境中。我们提供了用于成本效益实验设计的最佳 EEG 导数的有用建议，从而可以在未来的研究中增加样本量。
