Department of Psychiatry, University of Wisconsin-Madison, Madison, WI.
School of Psychological Sciences, Monash University, Clayton, Australia.
eNeuro. 2017 Oct 4;4(5). doi: 10.1523/ENEURO.0085-17.2017. eCollection 2017 Sep-Oct.
A significant problem in neuroscience concerns the distinction between neural processing that is correlated with conscious percepts from processing that is not. Here, we tested if a hierarchical structure of causal interactions between neuronal populations correlates with conscious perception. We derived the hierarchical causal structure as a pattern of integrated information, inspired by the integrated information theory (IIT) of consciousness. We computed integrated information patterns from intracranial electrocorticography (ECoG) from six human neurosurgical patients with electrodes implanted over lateral and ventral cortices. During recording, subjects viewed continuous flash suppression (CFS) and backward masking (BM) stimuli intended to dissociate conscious percept from stimulus, and unmasked suprathreshold stimuli. Object-sensitive areas revealed correspondence between conscious percepts and integrated information patterns. We quantified this correspondence using unsupervised classification methods that revealed clustering of visual experiences with integrated information, but not with broader information measures including mutual information and entropy. Our findings point to a significant role of locally integrated information for understanding the neural substrate of conscious object perception.
神经科学中的一个重大问题是区分与意识知觉相关的神经处理和不相关的神经处理。在这里,我们测试了神经元群体之间的因果相互作用的层次结构是否与意识知觉相关。我们从颅内脑电图(ECoG)中推导了层次因果结构,该结构受意识综合信息理论(IIT)的启发。我们从六个接受过电极植入的外侧和腹侧皮质的人类神经外科患者的 ECoG 中计算了综合信息模式。在记录过程中,受试者观看了旨在将意识知觉与刺激分离的连续闪光抑制(CFS)和后向掩蔽(BM)刺激,以及未掩蔽的阈上刺激。物体敏感区域显示出意识知觉与综合信息模式之间的对应关系。我们使用无监督分类方法来量化这种对应关系,该方法揭示了视觉体验与综合信息的聚类,而与互信息和熵等更广泛的信息度量没有聚类。我们的发现表明,局部综合信息在理解意识物体知觉的神经基础方面起着重要作用。