Study of syncope reveals brain signs of near-death experiences
The research involved 22 healthy volunteers who experienced controlled transient brain hypoxia with loss of consciousness, monitored with a high-density electroencephalogram (EEG) featuring 256 sensors. This allowed visualization of cortical activation during fainting episodes. Upon awakening, the volunteers' memories were evaluated. Over a third of the participants reported memories that aligned with the criteria for NDEs, such as accelerated thoughts, out-of-body experiences, seeing past scenes, and sensations of entering an extraterrestrial world. Additionally, participants reported auditory visions, hallucinations, feelings of euphoria, and a clearer mind during the laboratory-induced cerebral hypoxia.
The study identified specific electroencephalographic (EEG) signatures that predict the intensity of near-death experiences (NDEs) in healthy volunteers. Nearly 20 years ago, Steven Laureys, neurologist and founder of the Coma Science Group, initiated the studies on NDEs, now directed by Charlotte Martial, establishing the foundation for this research field in Liège.
Charlotte Martial, co-first author and post-doctoral researcher at the Coma Science Group, says: " Although we should be cautious in interpreting these results, this discovery opens up new perspectives for understanding the neurobiological mechanisms underlying NDEs. "
" During a fainting episode, dreamlike experiences characterised by extraordinary and mystical aspects can emerge. These experiences, some of which may bear the signature of an NDE, appear on the EEG as spikes in slow-frequency activity bands" adds co-author Vanessa Charland-Verville. She was responsible for acquiring the EEG measurements under the medical supervision of resuscitator Prof. Didier Ledoux, with analysis conducted by Prof. Andrea Piarulli of the University of Pisa.
Professor Steven Laureys concludes: " Our study shows that the EEG activity recorded during loss of consciousness can predict the intensity of the NDEs reported by volunteers after syncope. Specifically, bursts of activity in the delta and theta frequency bands and increased EEG complexity in brain areas involved in “seflf-consciousness” were identified as markers of the disconnected states of consciousness seemingly characteristic of NDEs. "
Source
EEG signature of near-death-like experiences during syncope-induced periods of unresponsiveness
Martial C. et Piarulli A., Gosseries O., Cassol H., Ledoux D., et Charland-Verville V. Laureys S., NeuroImage, 2024. DOI : https://doi.org/10.1016/j.neuroimage.2024.120759
