Human consciousness is supported by dynamic complex patterns of brain signal coordination
Athena Demertzi, Enzo Tagliazucchi, Stanislas Dehaene, Gustavo Deco, Pablo Barttfeld, Federico Raimondo, Charlotte Martial, Davinia Fernández‐Espejo, Benjamin Rohaut, Henning U. Voss, Nicholas D. Schiff, Adrian M. Owen, Steven Laureys, Lionel Naccache, Jacobo Sitt
Science Advances February 1, 2019 DOI: 10.1126/sciadv.aat7603 via OpenAlex
Summary
Consciousness depends on the brain's ability to sustain rich, dynamic patterns of signal coordination. Using functional magnetic resonance imaging, a complex pattern of coordinated and anticoordinated signals characterized healthy individuals and minimally conscious patients. Unresponsive patients showed low interareal phase coherence mainly mediated by structural connectivity, with fewer transitions between patterns. This complex pattern was also seen in patients with covert cognition who could perform mental imagery tasks, validating its link to consciousness. Anesthesia increased the probability of the less complex pattern to levels seen in unresponsive patients, confirming its role in unconsciousness. These results establish generalizable fingerprints of conscious and unconscious states after brain damage.
Study at a glance
| Characteristics | Observational cohort Peer reviewed |
|---|---|
| Population | Healthy individuals, minimally conscious patients, unresponsive patients, and patients with covert cognition |
| Keywords | Consciousness Unconscious mind Neuroscience Cognitive science Signal programming language |
| Citations | 545 |
| Key finding | Consciousness rests on the brain's ability to sustain rich, dynamic patterns of coordinated and anticoordinated signals, while unconscious states show low interareal phase coherence mainly mediated by structural connectivity. |
Abstract
Adopting the framework of brain dynamics as a cornerstone of human consciousness, we determined whether dynamic signal coordination provides specific and generalizable patterns pertaining to conscious and unconscious states after brain damage. A dynamic pattern of coordinated and anticoordinated functional magnetic resonance imaging signals characterized healthy individuals and minimally conscious patients. The brains of unresponsive patients showed primarily a pattern of low interareal phase coherence mainly mediated by structural connectivity, and had smaller chances to transition between patterns. The complex pattern was further corroborated in patients with covert cognition, who could perform neuroimaging mental imagery tasks, validating this pattern's implication in consciousness. Anesthesia increased the probability of the less complex pattern to equal levels, validating its implication in unconsciousness. Our results establish that consciousness rests on the brain's ability to sustain rich brain dynamics and pave the way for determining specific and generalizable fingerprints of conscious and unconscious states.