MindScope Program, Allen Institute, Seattle, United States.
Department of Biomedical and Clinical Sciences "L. Sacco", University of Milan, Milan, Italy.
Elife. 2023 Jun 26;12:RP84630. doi: 10.7554/eLife.84630.
Perturbational complexity analysis predicts the presence of consciousness in volunteers and patients by stimulating the brain with brief pulses, recording EEG responses, and computing their spatiotemporal complexity. We examined the underlying neural circuits in mice by directly stimulating cortex while recording with EEG and Neuropixels probes during wakefulness and isoflurane anesthesia. When mice are awake, stimulation of deep cortical layers reliably evokes locally a brief pulse of excitation, followed by a biphasic sequence of 120 ms profound period and a excitation. A similar pattern, partially attributed to burst spiking, is seen in thalamic nuclei and is associated with a pronounced late component in the evoked EEG. We infer that cortico-thalamo-cortical interactions drive the long-lasting evoked EEG signals elicited by deep cortical stimulation during the awake state. The cortical and thalamic off period and rebound excitation, and the late component in the EEG, are reduced during running and absent during anesthesia.
通过用短暂脉冲刺激大脑、记录脑电图反应并计算它们的时空复杂性，扰动复杂性分析可预测志愿者和患者是否有意识。我们在清醒和异氟烷麻醉期间通过直接刺激皮层并记录脑电图和神经像素探针，在小鼠中研究了潜在的神经回路。当老鼠清醒时，深层皮层的刺激可靠地引发局部短暂的兴奋脉冲，随后是 120 毫秒的深抑制和兴奋的双相序列。类似的模式，部分归因于爆发尖峰，在丘脑核中可见，并与诱发脑电图中的明显晚成分相关。我们推断，皮层-丘脑-皮层相互作用驱动在清醒状态下由深层皮层刺激引起的持久诱发脑电图信号。在跑步时，皮层和丘脑的抑制和反弹兴奋以及脑电图的晚成分减少，而在麻醉时则不存在。
