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arXiv · 1709.00050

The signatures of conscious access and phenomenology are consistent with large-scale brain communication at criticality

Abstract

Conscious awareness refers to the association of information processing in the brain that is accompanied by subjective, reportable experiences. Current models of conscious access propose that sufficiently strong sensory stimuli ignite a global network of regions allowing further processing. The immense number of possible experiences indicates that brain activity associated with conscious awareness must be highly differentiated. However, information must also be integrated to account for the unitary nature of consciousness. We present a conceptual computational model that identifies conscious access with self-sustained percolation in an anatomical network. We show that if activity propagates at the critical threshold, the amount of integrated information (Phi) is maximal after conscious access, as well as other related markers. We also identify a posterior hotspot of regions with high levels of information sharing during conscious access. Finally, competitive activity spreading qualitatively describes the results of paradigms such as backward masking and binocular rivalry.

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BibTeXRIS

Enzo Tagliazucchi. 2017-08-31. The signatures of conscious access and phenomenology are consistent with large-scale brain communication at criticality. https://doi.org/10.1016/j.concog.2017.08.008

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