Salti Moti, Monto Simo, Charles Lucie, King Jean-Remi, Parkkonen Lauri, Dehaene Stanislas
Cognitive Neuroimaging Unit, Institut National de la Santé et de la Recherche Médicale, Gif sur Yvette, France.
Elife. 2015 May 21;4:e05652. doi: 10.7554/eLife.05652.
The neural correlates of consciousness are typically sought by comparing the overall brain responses to perceived and unperceived stimuli. However, this comparison may be contaminated by non-specific attention, alerting, performance, and reporting confounds. Here, we pursue a novel approach, tracking the neuronal coding of consciously and unconsciously perceived contents while keeping behavior identical (blindsight). EEG and MEG were recorded while participants reported the spatial location and visibility of a briefly presented target. Multivariate pattern analysis demonstrated that considerable information about spatial location traverses the cortex on blindsight trials, but that starting ≈270 ms post-onset, information unique to consciously perceived stimuli, emerges in superior parietal and superior frontal regions. Conscious access appears characterized by the entry of the perceived stimulus into a series of additional brain processes, each restricted in time, while the failure of conscious access results in the breaking of this chain and a subsequent slow decay of the lingering unconscious activity.
意识的神经关联通常是通过比较大脑对感知到和未感知到的刺激的整体反应来寻找的。然而，这种比较可能会受到非特异性注意力、警觉性、表现和报告混淆因素的影响。在这里，我们采用一种新颖的方法，在保持行为相同（盲视）的情况下，追踪有意识和无意识感知内容的神经元编码。在参与者报告短暂呈现目标的空间位置和可见性时，记录脑电图（EEG）和脑磁图（MEG）。多变量模式分析表明，在盲视试验中，关于空间位置的大量信息穿过皮层，但在刺激开始后约270毫秒开始，有意识感知刺激所特有的信息出现在顶叶上部和额叶上部区域。意识通达似乎以被感知的刺激进入一系列额外的大脑过程为特征，每个过程都有时间限制，而意识通达的失败则导致这条链条的中断以及随后残留的无意识活动的缓慢衰减。
