Quantifying arousal and awareness in altered states of consciousness using interpretable deep learning
Minji Lee, Leandro R. D. Sanz, Alice Barra, Audrey Wolff, Jaakko O. Nieminen, Melanie Boly, Mario Rosanova, Silvia Casarotto, Olivier Bodart, Jitka Annen, Aurore Thibaut, Rajanikant Panda, Vincent Bonhomme, Marcello Massimini, Giulio Tononi, Steven Laureys, Olivia Gosseries, Seong–whan Lee
Nature Communications February 25, 2022 DOI: 10.1038/s41467-022-28451-0 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Observational cohort Peer reviewed |
|---|---|
| Sample size | 71 |
| Population | Healthy individuals during sleep, individuals under general anesthesia, and patients with severe brain injury |
| Intervention | transcranial magnetic stimulation |
| Topics | Altered states of consciousness |
| Keywords | Arousal Consciousness Altered state Cognitive psychology Artificial intelligence Deep learning |
| Citations | 120 |
| Key findings | The explainable consciousness indicator simultaneously quantifies arousal and awareness, clearly distinguishing states with low arousal and high awareness, such as ketamine-induced anesthesia and REM sleep, from other states. |
Abstract
Consciousness can be defined by two components: arousal (wakefulness) and awareness (subjective experience). However, neurophysiological consciousness metrics able to disentangle between these components have not been reported. Here, we propose an explainable consciousness indicator (ECI) using deep learning to disentangle the components of consciousness. We employ electroencephalographic (EEG) responses to transcranial magnetic stimulation under various conditions, including sleep (n = 6), general anesthesia (n = 16), and severe brain injury (n = 34). We also test our framework using resting-state EEG under general anesthesia (n = 15) and severe brain injury (n = 34). ECI simultaneously quantifies arousal and awareness under physiological, pharmacological, and pathological conditions. Particularly, ketamine-induced anesthesia and rapid eye movement sleep with low arousal and high awareness are clearly distinguished from other states. In addition, parietal regions appear most relevant for quantifying arousal and awareness. This indicator provides insights into the neural correlates of altered states of consciousness.
Comparable studies
Other observational and cohort studies on altered states of consciousness, most cited first.
| Study | Year | Design | Participants |
|---|---|---|---|
| Neural correlates of the DMT experience assessed with multivariate EEG. 6 female, 7 male human participants | 2019 | Observational cohort | n = 13 |
| Measures of entropy and complexity in altered states of consciousness Subjects during resting wakefulness, different sleep stages, and epileptic seizures | 2017 | Observational study | |
| Altered States of Consciousness and Short-Term Psychological After-Effects Induced by the First Time Ritual Use of Ayahuasca in an Urban Context in Brazil First-time ayahuasca users in Santo Daime and União do Vegetal rituals | 2005 | Observational cohort | n = 28 |
| Subanaesthetic ketamine and altered states of consciousness in humans Human volunteers | 2018 | Observational study | n = 15 |
| Neural and subjective effects of inhaled N,N-dimethyltryptamine in natural settings. Healthy and experienced participants | 2021 | Observational field study | n = 35 |
Citations in the library
Cited by 17
- Critical dynamics in spontaneous EEG predict anesthetic-induced loss of consciousness and perturbational complexity. Communications Biology August 5, 2024
- A synergistic workspace for human consciousness revealed by Integrated Information Decomposition. Elife July 18, 2024
- The nature of consciousness in anaesthesia BJA Open September 26, 2023
- Unravelling consciousness and brain function through the lens of time, space, and information Trends in Neurosciences May 31, 2024
- Psychedelics and disorders of consciousness: the current landscape and the path forward. Neuroscience of Consciousness June 15, 2024
and 12 more in the library
Cites 18
- Breakdown of Cortical Effective Connectivity During Sleep Science September 29, 2005
- A Theoretically Based Index of Consciousness Independent of Sensory Processing and Behavior Science Translational Medicine August 14, 2013
- Stratification of unresponsive patients by an independently validated index of brain complexity Annals of Neurology September 22, 2016
- Unresponsiveness ≠ Unconsciousness Anesthesiology February 7, 2012
- The spectral exponent of the resting EEG indexes the presence of consciousness during unresponsiveness induced by propofol, xenon, and ketamine Neuroimage January 11, 2019
and 13 more in the library