Department of Neurological Diagnosis and Restoration, Graduate School of Medicine, Osaka University, Suita 565-0871, Japan; Department of Neurosurgery, Otemae Hospital, Osaka 540-0008, Japan; Endowed Research Department of Clinical Neuroengineering, Global Center for Medical Engineering and Informatics, Osaka University, Suita 565-0871, Japan.
Department of Neurosurgery, Graduate School of Medicine, Osaka University, Suita 565-0871, Japan.
Clin Neurophysiol. 2021 Jun;132(6):1243-1253. doi: 10.1016/j.clinph.2021.03.007. Epub 2021 Mar 26.
High-frequency activities (HFAs) and phase-amplitude coupling (PAC) are key neurophysiological biomarkers for studying human epilepsy. We aimed to clarify and visualize how HFAs are modulated by the phase of low-frequency bands during seizures.
We used intracranial electrodes to record seizures of focal epilepsy (12 focal-to-bilateral tonic-clonic seizures and three focal-aware seizures in seven patients). The synchronization index, representing PAC, was used to analyze the coupling between the amplitude of ripples (80-250 Hz) and the phase of lower frequencies. We created a video in which the intracranial electrode contacts were scaled linearly to the power changes of ripple.
The main low frequency band modulating ictal-ripple activities was the θ band (4-8 Hz), and after completion of ictal-ripple burst, δ (1-4 Hz)-ripple PAC occurred. The ripple power increased simultaneously with rhythmic fluctuations from the seizure onset zone, and spread to other regions.
Ripple activities during seizure evolution were modulated by the θ phase. The PAC phenomenon was visualized as rhythmic fluctuations.
Ripple power associated with seizure evolution increased and spread with fluctuations. The θ oscillations related to the fluctuations might represent the common neurophysiological processing involved in seizure generation.
高频活动（HFAs）和相位-振幅耦合（PAC）是研究人类癫痫的关键神经生理生物标志物。我们旨在阐明并可视化在癫痫发作过程中低频带的相位如何调节 HFAs。
我们使用颅内电极记录局灶性癫痫发作（7 名患者中的 12 例局灶性双侧强直阵挛发作和 3 例局灶性意识发作）。使用同步指数（代表 PAC）分析棘波（80-250 Hz）振幅与较低频率相位之间的耦合。我们创建了一个视频，其中颅内电极接触以线性方式按棘波功率变化进行缩放。
主要低频带调节癫痫棘波活动的是θ带（4-8 Hz），在癫痫棘波爆发完成后，出现 δ（1-4 Hz）-棘波 PAC。棘波功率随着起源区的节律性波动而同步增加，并扩散到其他区域。
癫痫发作过程中棘波活动由θ 相位调节。PAC 现象被可视化成节律性波动。
与癫痫发作演变相关的棘波功率增加并随波动扩散。与波动相关的θ 振荡可能代表了参与癫痫发作产生的共同神经生理处理。
