Werth E, Achermann P, Borbély A A
Institute of Pharmacology, University of Zürich, Switzerland.
J Sleep Res. 1997 Jun;6(2):102-12. doi: 10.1046/j.1365-2869.1997.d01-36.x.
The brain topography of power spectra along the antero-posterior (A-P) axis was studied in the all-night human sleep EEG. Spectra (0.25 - 25.0 Hz) were computed for an anterior (A; F3-C3), a middle (M; C3-P3) and a posterior (P; P3-O1) bipolar derivation, and the spectral gradients between two adjacent derivations were expressed by power ratios (A/M and M/P). At NREM-REM sleep transitions a power shift from A to M was present over almost the entire frequency range, while the direction of shifts between M and P differed between frequency bands. Within NREM sleep, frequency specific power gradients were present: In the low delta band power in both A (0.25 Hz bin) and P (0.25-1.0 Hz bins) was higher than in M. In the 4-9 Hz range the relation was A > M > P, and in the 15 - 25 Hz range power was largest in M. Power in the spindle frequency range was highest at 11.75 Hz in M, and at 13.5 - 13.75 Hz in A. Topographical differences were seen also in the temporal changes of power across and within NREM sleep episodes. Whereas NREM sleep power in the 2-Hz bin was higher in A than in M in the first episode, this difference vanished in the course of the night. This result points to a specific involvement of frontal parts of the cortex in sleep homeostasis. The regional differences in sleep EEG spectra indicate that sleep is not only a global phenomenon but also a local brain process with a different regional involvement of neuronal populations.
在整夜的人类睡眠脑电图中，研究了沿前后（A-P）轴的功率谱脑地形图。计算了前（A；F3-C3）、中（M；C3-P3）和后（P；P3-O1）双极导联的频谱（0.25 - 25.0 Hz），两个相邻导联之间的频谱梯度用功率比（A/M和M/P）表示。在非快速眼动睡眠（NREM）-快速眼动睡眠（REM）转换期间，几乎在整个频率范围内都出现了从A到M的功率转移，而M和P之间的转移方向在不同频段有所不同。在NREM睡眠中，存在频率特异性功率梯度：在低δ频段，A（0.25 Hz频段）和P（0.25 - 1.0 Hz频段）的功率均高于M。在4 - 9 Hz范围内，关系为A > M > P，在15 - 25 Hz范围内，M的功率最大。纺锤波频率范围内的功率在M中为11.75 Hz时最高，在A中为13.5 - 13.75 Hz时最高。在NREM睡眠阶段内和阶段间功率的时间变化中也观察到了地形差异。在第一个阶段，2 Hz频段的NREM睡眠功率在A中高于M，但在夜间过程中这种差异消失了。这一结果表明皮质额叶部分在睡眠稳态中具有特定作用。睡眠脑电图频谱的区域差异表明，睡眠不仅是一种整体现象，也是一种局部脑过程，神经元群体在不同区域发挥作用。
