低频光诱发脑电在浅睡期的样本熵复杂度分析

Sample Entropy Evaluation of EEG complexity Based on Low-Frequency Photon Stimulation in Light Sleep

睡眠障碍患者通常表现为从浅睡期进入深睡期存在困难,分析浅睡期脑电波的变化对研究睡眠效率和睡眠质量至关重要。通过分析低频光刺激下睡眠过程中脑电波的复杂度值变化,研究人在浅睡期脑电波对光刺激的响应,进而探讨外部光刺激对睡眠过程中脑电波的影响。使用美国neuroscan型脑电图仪,采集10例志愿者的光刺激睡眠和正常睡眠的脑电数据。首先,利用时频分析,对睡眠过程中的脑电信号进行分期,获得浅睡期脑电信号;然后,使用小波包分解,获得该期脑电波的各频段分量(δ波、θ波、α波和纺锤波);接着,采用样本熵算法,分别计算浅睡期脑电信号的复杂度以及各频段脑电波的复杂度;最后,对志愿者在光刺激(5 Hz)和正常睡眠下浅睡期脑电复杂度进行比较,研究光刺激对脑电复杂度的响应情况。结果显示:在低频光刺激下,浅睡期脑电波复杂度的均值为0.514 15,明显低于正常睡眠复杂度的均值0.589 23,在中央区和顶区有显著性差异(P<0.05)。研究表明,5Hz光刺激可诱发浅睡期θ波的同步响应,增强脑电波的节律性,有助于更好地进入深度睡眠。

Patients with sleep disorders have difficulties entering deep sleep from light sleep. It is important to research the changes of EEG during the light sleep for sleep efficiency and quality. In this paper, the EEG response during the light sleep under photon stimulation was studied by analyzing the EEG complexity changes, and the impact of photon stimulation on sleep EEG was studied as well. Ten volunteers＇ EEG data during photon stimulation and normal sleep were gained by Neuroscan. Firstly, the EEG data of light sleep were obtained by using time-frequency analysis. Secondly, the theta waves, delta waves, alpha waves and the spindles were extracted from the EEG by using wavelet packet decomposition. Thirdly, the complexity of EEG and its components with different frequencies during the light sleep were calculated by using sample entropy. Lastly, the light sleep EEG complexity between normal sleep and photon stimulation （5 Hz）sleep was compared to research the impact of photon stimulation. We found the average value of EEG complexity under photon stimulation is 0. 514 15, significantly less than the average value of normal sleep, 0. 589 23, especially in central and parietal region （ P 〈 0.05 ）. The conclusion is that photon stimulation （ 5 Hz ） can induce the synchronous response of EEG, and strengthen the EEG rhythm, which helps the brain enter deep sleep.