  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.
