Wright K P, Badia P, Wauquier A
Department of Psychology, Bowling Green State University, Ohio 43403, USA.
Sleep. 1995 Dec;18(10):880-9. doi: 10.1093/sleep/18.10.880.
Changes in electroencephalographic (EEG) spectral power, coherence and frequency were examined for the last minute of wakefulness and the first minute of sleep via topographical mapping. Data were also analyzed across sequential 1-minute samples of wake, stage 1 and stage 2 sleep. Not all brain regions exhibited the same EEG changes during the transition and not all brain regions were found to change at the same time. Brain sites closest to the midline (e.g. F4, C4, P4, O2) showed significant changes in EEG power (increases in theta and decreases in alpha power) during the transition to sleep, whereas brain sites most lateral to the midline (e.g. Fp2, F8, T4) showed little change. Decreases in alpha coherence were observed from wakefulness to sleep for brain site comparisons furthest away from each other (e.g. T3 vs. T4, T5 vs. T6, F7 vs. F8, F3 vs. O1, F4 vs. O2). Spectral analysis of EEG activity revealed that the time of significant change in EEG power varies among brain regions. Decreases in alpha power continued to occur later into the transition period for the posterior regions of the brain (O2, P4).
通过地形图检查了清醒最后一分钟和睡眠第一分钟的脑电图（EEG）频谱功率、相干性和频率变化。还对清醒、1期睡眠和2期睡眠的连续1分钟样本进行了数据分析。并非所有脑区在转换过程中都表现出相同的脑电图变化，也并非所有脑区都在同一时间发生变化。最靠近中线的脑区（如F4、C4、P4、O2）在向睡眠转换过程中脑电图功率有显著变化（θ波增加，α波功率降低），而最靠近中线外侧的脑区（如Fp2、F8、T4）变化很小。对于彼此距离最远的脑区比较（如T3与T4、T5与T6、F7与F8、F3与O1、F4与O2），从清醒到睡眠观察到α波相干性降低。脑电图活动的频谱分析表明，脑电图功率显著变化的时间在不同脑区有所不同。大脑后部区域（O2、P4）在转换期后期α波功率持续下降。
