College of Biomedical Engineering & Instrument Science, Zhejiang University, Hangzhou 310027, China.
Beacons of Excellence Research and Innovation Institute, University of Nottingham, Ningbo 315100 Zhejiang, China.
Neurosci Res. 2022 Dec;185:20-28. doi: 10.1016/j.neures.2022.09.002. Epub 2022 Sep 6.
Phase-amplitude coupling (PAC) plays an important role in anesthetic-induced unconsciousness. The delta-alpha PAC signature during anesthetic-induced unconsciousness is gradually becoming known; however, the frequency dependence and spatial characteristics of PAC are still unclear. Multi-channel electroencephalography (EEG) was performed during the loss and recovery phases of consciousness in patients undergoing general anesthesia using sevoflurane. First, a spectral analysis was used to investigate the power change of the different frequency bands in the EEG signals. Second, PAC comodulogram analysis was performed to confirm the frequencies of the PAC phase drivers. Finally, to investigate the spatial characteristics of PAC, a novel PAC network was constructed using within- and cross-lead PAC, and a K-means clustering algorithm was used to identify PAC network patterns. Our results show that, in addition to the delta-alpha PAC, unconsciousness induced by sevoflurane was accompanied by spatial non-uniform alpha-gamma PAC in the cortical network, and dynamic PAC patterns between the anterior and posterior brain were observed during the unconscious phase. The dynamic transition of PAC network patterns indicates that brain states under sevoflurane-induced unconsciousness emerge from the regulation of functional integration and segregation instantiated by delta-alpha and alpha-gamma PAC.
相位-振幅耦合 (PAC) 在麻醉诱导的意识丧失中起着重要作用。麻醉诱导意识丧失期间的 delta-alphaPAC 特征逐渐被人们所认识；然而，PAC 的频率依赖性和空间特征仍不清楚。在接受七氟醚全身麻醉的患者的意识丧失和恢复阶段进行了多通道脑电图 (EEG) 检测。首先，进行了频谱分析以研究 EEG 信号中不同频段的功率变化。其次，进行了 PAC 共调图分析以确认 PAC 相位驱动的频率。最后，为了研究 PAC 的空间特征，使用内导和跨导 PAC 构建了一个新的 PAC 网络，并使用 K-均值聚类算法来识别 PAC 网络模式。我们的结果表明，除了 delta-alphaPAC 之外，七氟醚诱导的无意识还伴随着皮质网络中空间不均匀的 alpha-gammaPAC，并且在无意识阶段观察到前脑和后脑之间的动态 PAC 模式。PAC 网络模式的动态转变表明，七氟醚诱导的无意识下的大脑状态是由 delta-alpha 和 alpha-gammaPAC 体现的功能整合和分离的调节产生的。
