睡眠剥夺影响大脑功能区状态的非线性评价

采用近似熵研究睡眠剥夺（sleep deprivation，SD）对脑认知功能的影响，评价SD引起的大脑功能区状态的非线性变化．12名受试者在正常睡眠和一夜SD之后分别接受视觉注意力测试，记录自发脑电和诱发脑电，采用二维插值构建19导脑电近似熵脑信息图（brain information map，BIM）．结果表明，在SD状态下，自发脑电的近似熵在全脑范围内有不同程度的下降，额叶处大脑偏侧性发生变化，复杂度的中心从左脑转移到右脑；前额叶处诱发脑电近似熵值降低，而顶叶和颞叶处则升高．脑电近似熵可以作为指标来评价SD对脑认知功能的负向影响，BIM的变化趋势与从生理学及影像学角度的分析相吻合，与线性方法的研究结论一致，在一定程度上可以反映大脑功能状态，提供一条评价脑功能区状态变化趋势的思路．

Non-Linear Evaluation of Effects of Sleep Deprivation on Brain Functional States

To study the effect of sleep deprivation （SD） on cognitive brain function, we applied approximate entropy （ApEn） to assess the non-linear influence on brain functional states. Spontaneous electroencephalogram （EEG） and evoked visual EEG of twelve volunteers were recorded under normal state and after one night＇s SD. ApEn of nighteen leads of EEG data were calculated and brain information map （ BIM ） was reconstructed by using two-dimensional interpolation algorithm. Results show that after SD ApEn of spontaneous EEG decreases over the whole brain to some extents;while asymmetry of prefrontal lobes changes, and the center of high complexity shiftes from left to right hemisphere. By BIM of event related potential （ ERP ）, ApEn on prefrontal cortex decreases while that on parietal lobes and temporal lobes increase. ApEn can be regarded as a criterion to evaluate the negative influence of SD on cognitive brain function. Changes of BIM agree well with those deduced by physiological and functional imaging analysis, and is consistent with that from linear analysis. Therefore, ApEn BIM is a new way to directly describe brain functional states after SD.