EEG signature of near-death-like experiences during syncope-induced periods of unresponsiveness.
Charlotte Martial, Andrea Piarulli, Olivia Gosseries, Héléna Cassol, Didier Ledoux, Vanessa Charland-Verville, Steven Laureys
Neuroimage September 1, 2024 DOI: 10.1016/j.neuroimage.2024.120759 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Experimental study Peer reviewed |
|---|---|
| Sample size | 22 |
| Population | Healthy volunteers |
| Interventions | hyperventilation orthostasis Valsalva maneuvers |
| Duration | 22±8 seconds of syncope and unresponsiveness |
| Topics | Near-death experience |
| Keywords | Consciousness EEG Syncope Unresponsiveness |
| Citations | 10 |
| Key findings | Near-death-like experiences during fainting are associated with increased delta, theta, and beta2 band activity in temporal and frontal brain regions, along with higher neural complexity and connectivity. |
Abstract
During fainting, disconnected consciousness may emerge in the form of dream-like experiences. Characterized by extra-ordinary and mystical features, these subjective experiences have been associated to near-death-like experiences (NDEs-like). We here aim to assess brain activity during syncope-induced disconnected consciousness by means of high-density EEG monitoring. Transient loss of consciousness and unresponsiveness were induced in 27 healthy volunteers through hyperventilation, orthostasis, and Valsalva maneuvers. Upon awakening, subjects were asked to report memories, if any. The Greyson NDE scale was used to evaluate the potential phenomenological content experienced during the syncope-induced periods of unresponsiveness. EEG source reconstruction assessed cortical activations during fainting, which were regressed out with subjective reports collected upon recovery of normal consciousness. We also conducted functional connectivity, graph-theoretic and complexity analyses. High quality high-density EEG data were obtained in 22 volunteers during syncope and unresponsiveness (lasting 22±8 s). NDE-like features (Greyson NDE scale total score ≥7/32) were apparent for eight volunteers and characterized by higher activity in delta, theta and beta2 bands in temporal and frontal regions. The richness of the NDE-like content was associated with delta, theta and beta2 bands cortical current densities, in temporal, parietal and frontal lobes, including insula, right temporoparietal junction, and cingulate cortex. Our analyses also revealed a higher complexity and that networks related to delta, theta, and beta2 bands were characterized by a higher overall connectivity paralleled by a higher segregation (i.e., local efficiency) and a higher integration (i.e., global efficiency) for the NDE-like group compared to the non-NDE-like group. Fainting-induced NDE-like episodes seem to be sustained by surges of neural activity representing promising markers of disconnected consciousness.
Comparable studies
Other experimental studies on near-death experience, most cited first.
| Study | Year | Design | Participants |
|---|---|---|---|
| Brain activity in near-death experiencers during a meditative state Near-death experiencers | 2009 | Within-subjects experimental design with Meditation and Control conditions | |
| Meditation-Induced Near-Death Experiences: a 3-Year Longitudinal Study Advanced Buddhist meditators | 2018 | Longitudinal within-subjects comparison with control conditions and embedded qualitative analysis | n = 12 |
| Designing a "Near-Death Experience" Reality Testing System. | 2021 | Experimental design | |
| COMPARING THE DIFFERENCE IN NURSES' KNOWLEDGE AND ATTITUDES TOWARD NEAR-DEATH EXPERIENCES (NDES) BEFORE AND AFTER RECEIVING NDE EDUCATION Registered nurses employed in Kaiser Permanente Northern California facilities | 2026 | Quasi-experimental study | n = 41 |
| Teaching about near-death experiences: the effectiveness of using The Day I Died. Advanced undergraduates at a southwestern university (66 in the experimental group; 39... | 2011 | Quasi-experimental study | n = 105 |
Citations in the library
Cited by 10
- A neuroscientific model of near-death experiences. Nature Reviews Neurology June 1, 2025
- Complex slow waves in the human brain under 5-MeO-DMT. Cell Reports July 22, 2025
- Near-death experience during cardiac arrest and consciousness beyond the brain: a narrative review. International Review of Psychiatry 2025
- The entropic brain today Brain December 12, 2025
- Near‐Death Experience During Emergency Ketamine Use: A Case Report Brain and Behavior October 1, 2025
and 5 more in the library
Cites 25
- An information integration theory of consciousness BMC Neuroscience November 2, 2004
- Neural correlates of consciousness: progress and problems Nature Reviews Neuroscience April 20, 2016
- Near-death experience in survivors of cardiac arrest: a prospective study in the Netherlands The Lancet December 1, 2001
- Unresponsiveness ≠ Unconsciousness Anesthesiology February 7, 2012
- Disruption of Frontal–Parietal Communication by Ketamine, Propofol, and Sevoflurane Anesthesiology May 22, 2013
and 20 more in the library