Institute of Physics, Saratov State University, 410012 Saratov, Russia.
Saratov State Medical University, 410005 Saratov, Russia.
Chaos. 2024 Aug 1;34(8). doi: 10.1063/5.0227179.
This paper presents the results of a study of the characteristics of phase synchronization between electrocardiography(ECG) and electroencephalography (EEG) signals during night sleep. Polysomnographic recordings of eight generally healthy subjects and eight patients with obstructive sleep apnea syndrome were selected as experimental data. A feature of this study was the introduction of an instantaneous phase for EEG and ECG signals using a continuous wavelet transform at the heart rate frequency using the concept of time scale synchronization, which eliminated the emergence of asynchronous areas of behavior associated with the "leaving" of the fundamental frequency of the cardiovascular system. Instantaneous phase differences were examined for various pairs of EEG and ECG signals during night sleep, and it was shown that in all cases the phase difference exhibited intermittency. Laminar areas of behavior are intervals of phase synchronization, i.e., phase capture. Turbulent intervals are phase jumps of 2π. Statistical studies of the observed intermittent behavior were carried out, namely, distributions of the duration of laminar sections of behavior were estimated. For all pairs of channels, the duration of laminar phases obeyed an exponential law. Based on the analysis of the movement of the phase trajectory on a rotating plane at the moment of detection of the turbulent phase, it was established that in this case the eyelet intermittency was observed. There was no connection between the statistical characteristics of laminar phase distributions for intermittent behavior and the characteristics of night breathing disorders (apnea syndrome). It was found that changes in statistical characteristics in the phase synchronization of EEG and ECG signals were correlated with blood pressure at the time of signal recording in the subjects, which is an interesting effect that requires further research.
本文介绍了一项研究的结果，该研究探讨了夜间睡眠期间心电图(ECG)和脑电图(EEG)信号之间相位同步的特征。选择了 8 名一般健康受试者和 8 名阻塞性睡眠呼吸暂停综合征患者的多导睡眠记录作为实验数据。本研究的一个特点是，在心率频率下使用连续小波变换引入 EEG 和 ECG 信号的瞬时相位，使用时间尺度同步的概念，消除了与心血管系统基本频率“离开”相关的异步行为区域的出现。在夜间睡眠期间，检查了各种 EEG 和 ECG 信号对之间的瞬时相位差，并表明在所有情况下，相位差都表现出间歇性。层状行为区域是相位同步的区间，即相位捕获。湍流区间是 2π 的相位跳跃。对观察到的间歇性行为进行了统计研究，即估计了行为层状部分持续时间的分布。对于所有通道对，层状相位的持续时间都服从指数定律。基于在检测到湍流相位时旋转平面上相位轨迹运动的分析，确定在这种情况下观察到了眼状间歇性。间歇性行为的层状相位分布的统计特征与夜间呼吸障碍（睡眠呼吸暂停综合征）的特征之间没有联系。研究发现，在 EEG 和 ECG 信号相位同步的统计特征变化与受试者记录信号时的血压有关，这是一个有趣的效果，需要进一步研究。
