Spontaneous cortical activity is transiently poised close to criticality
Spontaneous cortical activity is transiently poised close to criticality
复制标题
DOI：
10.1371/journal.pcbi.1005543
复制
发表时间：
2017-05-01
影响因子：
4.3
通讯作者：
Fregnac, Yves
中科院分区：
文献类型：
--
作者：
Hahn, Gerald;Ponce-Alvarez, Adrian;Fregnac, Yves
大脑活动在整个睡眠-觉醒周期甚至在麻醉过程中显示出大量的动力学。有人建议，临界性可以作为动力学多样性的一个统一原则。这一观点得到了支持的观察皮层活动的自发爆发与规模不变的大小和持续时间，称为神经元雪崩，在记录中观皮层信号。然而，存在的神经元雪崩尖峰活动一直模棱两可的研究报告，其存在和不存在。在这里，我们表明，尖峰活动的关键性的迹象可以改变同步和去同步皮质状态之间。我们分析了麻醉猫和清醒猴的初级视觉皮层的自发活动，发现神经元雪崩和临界性的热力学指标强烈依赖于神经元之间的集体同步，LFP波动和行为状态。我们发现，同步状态与临界状态，大的动态库和长期的闭眼时期，而despersized状态与亚临界状态，减少动态库，和眼睛打开的条件。我们的研究结果表明，在皮层动力学的临界是不稳定的，但在麻醉期间和不同的警惕状态之间的波动。
Brain activity displays a large repertoire of dynamics across the sleep-wake cycle and even during anesthesia. It was suggested that criticality could serve as a unifying principle underlying the diversity of dynamics. This view has been supported by the observation of spontaneous bursts of cortical activity with scale-invariant sizes and durations, known as neuronal avalanches, in recordings of mesoscopic cortical signals. However, the existence of neuronal avalanches in spiking activity has been equivocal with studies reporting both its presence and absence. Here, we show that signs of criticality in spiking activity can change between synchronized and desynchronized cortical states. We analyzed the spontaneous activity in the primary visual cortex of the anesthetized cat and the awake monkey, and found that neuronal avalanches and thermodynamic indicators of criticality strongly depend on collective synchrony among neurons, LFP fluctuations, and behavioral state. We found that synchronized states are associated to criticality, large dynamical repertoire and prolonged epochs of eye closure, while desynchronized states are associated to sub-criticality, reduced dynamical repertoire, and eyes open conditions. Our results show that criticality in cortical dynamics is not stationary, but fluctuates during anesthesia and between different vigilance states.