Behavioral and electrophysiological evidence for fast emergence of visual consciousness
Neuroscience of Consciousness January 1, 2015 Henry Railo, A. Revonsuo, M. Koivisto
People can report whether they consciously saw a visual stimulus in just over 200 milliseconds, and these reports are extremely reliable and not reflexive or unconscious. The neural events that cause conscious vision must happen before these reports. Late cortical processing in the fronto-parietal global neuronal workspace, which occurs around 300 milliseconds, starts after the fastest consciousness reports, so this late activity cannot directly reflect the emergence of visual consciousness. Instead, a negative amplitude difference spreading from occipital to frontal cortex around 160–220 milliseconds precedes the reports, suggesting this neural correlate underlies the emergence of conscious vision.