Cavelli Matias Lorenzo, Mao Rong, Findlay Graham, Driessen Kort, Bugnon Tom, Tononi Giulio, Cirelli Chiara
Department of Psychiatry, University of Wisconsin-Madison, Madison, WI 53719, USA.
Departamento de Fisiología de Facultad de Medicina, Universidad de la República, Montevideo 11800, Uruguay.
iScience. 2023 Feb 13;26(3):106186. doi: 10.1016/j.isci.2023.106186. eCollection 2023 Mar 17.
In humans, the level of consciousness is assessed by quantifying the spatiotemporal complexity of cortical responses using Perturbational Complexity Index (PCI) and related PCI (st, state transitions). Here we validate PCI in freely moving rats and mice by showing that it is lower in NREM sleep and slow wave anesthesia than in wake or REM sleep, as in humans. We then show that (1) low PCI is associated with the occurrence of an OFF period of neuronal silence; (2) stimulation of deep, but not superficial, cortical layers leads to reliable PCI changes across sleep/wake and anesthesia; (3) consistent PCI changes are independent of which single area is being stimulated or recorded, except for recordings in mouse prefrontal cortex. These experiments show that PCI can reliably measure vigilance states in unresponsive animals and support the hypothesis that it is low when an OFF period disrupts causal interactions in cortical networks.
在人类中，意识水平是通过使用微扰复杂性指数（PCI）和相关的PCI（st，状态转换）来量化皮质反应的时空复杂性来评估的。在这里，我们通过证明在自由活动的大鼠和小鼠中，PCI在非快速眼动睡眠和慢波麻醉状态下比在清醒或快速眼动睡眠状态下更低，就像在人类中一样，从而验证了PCI。然后我们表明：（1）低PCI与神经元沉默的静息期的出现有关；（2）刺激深层而非浅层皮质层会导致在睡眠/觉醒和麻醉状态下出现可靠的PCI变化；（3）一致的PCI变化与所刺激或记录的单个区域无关，但小鼠前额叶皮质的记录除外。这些实验表明，PCI可以可靠地测量无反应动物的警觉状态，并支持这样的假设，即当静息期破坏皮质网络中的因果相互作用时，PCI会降低。
