Department of Electrical and Computer Engineering, University of Houston, Houston, Texas 77204-4005, USA.
Psychophysiology. 2013 Mar;50(3):274-86. doi: 10.1111/psyp.12011. Epub 2013 Jan 14.
During sleep, the brain network processes sensory stimuli without awareness. Stimulation must affect differently brain networks in sleep versus wake, but these differences have yet to be quantified. We recorded cortical activity in stage 2 (SII) sleep and wake using EEG while a tone was intermittently played. Zero-lag correlation measured input to pairs of sensors in the network; cross-correlation and phase-lag index measured pairwise corticocortical connectivity. Our analysis revealed that under baseline conditions, the cortical network, in particular the central regions of the frontoparietal cortex, interact at a characteristic latency of 50 ms, but only during wake, not sleep. Nonsalient auditory stimulation causes far greater perturbation of connectivity from baseline in sleep than wake, both in the response to common input and corticocortical connectivity. The findings have key implications for sensory processing.
在睡眠中，大脑网络在无意识的情况下处理感官刺激。刺激必须以不同的方式影响睡眠和清醒时的大脑网络，但这些差异尚未被量化。我们在脑电图记录了 SII 睡眠和清醒时的皮层活动，同时间歇性播放了一个音调。零延迟相关测量了网络中对传感器对的输入；互相关和相位滞后指数测量了皮质间的连接。我们的分析表明，在基线条件下，皮层网络，特别是额顶叶皮层的中央区域，以 50ms 的特征潜伏期相互作用，但仅在清醒时，而不是睡眠时。非显性听觉刺激会导致睡眠时的连接比清醒时受到更大的干扰，无论是对共同输入的反应还是皮质间的连接。这些发现对感官处理具有重要意义。
