Nature Communications
February 25, 2022
Minji Lee, Leandro Sanz, Alice Barra et al.
120 citations
A deep-learning-based explainable consciousness indicator (ECI) uses EEG responses to transcranial magnetic stimulation and resting-state EEG to separately quantify arousal and awareness. Tested during sleep (n=6), general anesthesia (n=16), and severe brain injury (n=34), ECI distinguishes states such as ketamine-induced anesthesia and rapid eye movement sleep, which combine low arousal with high awareness. Parietal brain regions are most relevant for these measurements. The indicator offers a way to disentangle the two components of consciousness across physiological, pharmacological, and pathological conditions.
iScience
January 17, 2025
Paolo Cardone, Arthur Bonhomme, Vincent Bonhomme et al.
9 citations
In a small double-blind, placebo-controlled, cross-over trial with three adults who had prolonged disorders of consciousness after a coma, an intravenous sub-anesthetic dose of the atypical psychedelic ketamine increased brain complexity as measured by Lempel-Ziv complexity, but did not change the explainable consciousness indicator. Patients showed reduced spastic paresis and spent more time with their eyes open, yet their diagnosis of consciousness did not improve. No adverse effects occurred. The findings suggest a potential therapeutic role for ketamine in disorders of consciousness and support a link between brain complexity and conscious states.
Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Annual International Conference
July 1, 2019
Minji Lee, Benjamin Baird, Olivia Gosseries et al.
4 citations
Cortical networks show differences in functional integration and segregation across states of consciousness, but not in overall connectivity. In the beta frequency band, functional integration during wakefulness exceeded that during NREM sleep. In the theta band, functional segregation (transitivity and clustering coefficient) was stronger in NREM sleep without conscious experience than in wakefulness or REM sleep, while the opposite pattern appeared in the beta band. No significant differences in the weighted phase lag index were found among wakefulness, REM sleep with conscious experience, NREM sleep with conscious experience, and NREM sleep without conscious experience. These findings may relate to cortical bistability and contribute to understanding neural correlates of consciousness.