Cortical activity is more stable when sensory stimuli are consciously perceived.
Proceedings of the National Academy of Sciences of the United States of America April 21, 2015 Aaron Schurger, Ioannis Sarigiannidis, Lionel Naccache et al.
Conscious perception may involve the transient stabilization of distributed cortical networks, corresponding to a global brain-scale decision. Pattern-similarity analyses of MEG/EEG data from participants viewing threshold-level visual stimuli showed a decrease in variability across trials after stimulus onset, followed by a divergence in variability based on subjective report (seen/unseen), with seen trials exhibiting less variability. Within-trial stability alone could classify individual trials as seen or unseen. In patients with disorders of consciousness exposed to auditory stimuli, stability metrics diverged according to clinically diagnosed level of consciousness. Differences in signal strength could not account for these results.