Department of Psychology, University of Wisconsin-Madison, Madison, WI 53705, USA.
Department of Psychology, University of Wisconsin-Madison, Madison, WI 53705, USA.
Cell Syst. 2021 Apr 21;12(4):363-373.e11. doi: 10.1016/j.cels.2021.02.003. Epub 2021 Mar 16.
The neural substrates of consciousness remain elusive. Competing theories that attempt to explain consciousness disagree on the contribution of frontal versus posterior cortex and omit subcortical influences. This lack of understanding impedes the ability to monitor consciousness, which can lead to adverse clinical consequences. To test substrates and measures of consciousness, we recorded simultaneously from frontal cortex, parietal cortex, and subcortical structures, the striatum and thalamus, in awake, sleeping, and anesthetized macaques. We manipulated consciousness on a finer scale using thalamic stimulation, rousing macaques from continuously administered anesthesia. Our results show that, unlike measures targeting complexity, a measure additionally capturing neural integration (Φ) robustly correlated with changes in consciousness. Machine learning approaches show parietal cortex, striatum, and thalamus contributed more than frontal cortex to decoding differences in consciousness. These findings highlight the importance of integration between parietal and subcortical structures and challenge a key role for frontal cortex in consciousness.
意识的神经基础仍然难以捉摸。试图解释意识的竞争理论在额叶与顶叶皮层的贡献上存在分歧，并且忽略了皮质下的影响。这种缺乏理解阻碍了监测意识的能力，这可能导致不良的临床后果。为了测试意识的基质和测量方法，我们在清醒、睡眠和麻醉的猕猴中同时从额叶皮层、顶叶皮层和皮质下结构（纹状体和丘脑）进行记录。我们使用丘脑刺激在更精细的范围内操纵意识，使猕猴从持续给予的麻醉中苏醒。我们的结果表明，与针对复杂性的测量方法不同，另外捕捉神经整合（Φ）的测量方法与意识的变化具有很强的相关性。机器学习方法表明，顶叶皮层、纹状体和丘脑对意识差异的解码贡献大于额叶皮层。这些发现强调了顶叶和皮质下结构之间整合的重要性，并挑战了额叶皮层在意识中的关键作用。
