Cortical Neural Synchronization Underlies Primary Visual Consciousness of Qualia: Evidence from Event-Related Potentials.
Frontiers in Human Neuroscience January 1, 2016 Claudio Babiloni, Nicola Marzano, Andrea Soricelli et al.
Primary visual consciousness—whether a person reports seeing a stimulus—is associated with enhanced cortical neural synchronization, but the timing and brain regions involved depend on the type of visual feature. In three experiments using event-related potentials, seen and unseen trials showed no difference in the timing of neural responses, but the sources of brain activity differed. For visuospatial stimuli, consciousness involved higher activity in dorsal occipital and parietal areas around 400 milliseconds. For emotional face expressions, greater activity appeared in parietal and frontal areas at about 180 milliseconds. For written words, higher activity occurred in occipital, parietal, and temporal areas at about 230 milliseconds. These results suggest that primary visual consciousness arises from synchronizing different cortical networks depending on the visual feature, possibly forming a multidimensional palette of qualia.