Mukovski Mikhail, Chauvette Sylvain, Timofeev Igor, Volgushev Maxim
Department of Neurophysiology, Ruhr-University Bochum, Bochum, Germany.
Cereb Cortex. 2007 Feb;17(2):400-14. doi: 10.1093/cercor/bhj157. Epub 2006 Mar 17.
Oscillations of the local field potentials (LFPs) or electroencephalogram (EEG) at frequencies below 1 Hz are a hallmark of the slow-wave sleep. However, the timing of the underlying cellular events, which is an alternation of active and silent states of thalamocortical network, can be assessed only approximately from the phase of slow waves. Is it possible to detect, using the LFP or EEG, the timing of each episode of cellular activity or silence? With simultaneous recordings of the LFP and intracellular activity of 2-3 neocortical cells, we show that high-gamma-range (20-100 Hz) components in the LFP have significantly higher power when cortical cells are in active states as compared with silent-state periods. Exploiting this difference we have developed a new method, which uses the LFP signal to detect episodes of activity and silence of neocortical neurons. The method allows robust, reliable, and precise detection of timing of each episode of activity and silence of the neocortical network. It works with both surface and depth EEG, and its performance is affected little by the EEG prefiltering during recording. These results open new perspectives for studying differential operation of neural networks during periods of activity and silence, which rapidly alternate on the subsecond scale.
频率低于1赫兹的局部场电位（LFP）或脑电图（EEG）振荡是慢波睡眠的一个标志。然而，丘脑皮质网络活跃和静止状态交替的潜在细胞事件的时间，只能从慢波的相位大致评估。是否有可能利用LFP或EEG检测细胞活动或静止的每个时段的时间？通过同时记录LFP和2 - 3个新皮质细胞的细胞内活动，我们发现与静止状态期相比，当皮质细胞处于活跃状态时，LFP中的高伽马范围（20 - 100赫兹）成分具有显著更高的功率。利用这种差异，我们开发了一种新方法，该方法使用LFP信号来检测新皮质神经元的活动和静止时段。该方法能够可靠、精确地检测新皮质网络活动和静止的每个时段的时间。它适用于头皮脑电图和深部脑电图，并且其性能受记录期间脑电图预滤波的影响很小。这些结果为研究神经网络在活跃和静止期间的差异运作开辟了新的视角，这些状态在亚秒级迅速交替。
