PeerJ
January 1, 2019
Daniel Kondziella, Jens P Dreier, Markus Harboe Olsen
34 citations
Near-death experiences are reported by 10% of a large, diverse sample of 1,034 lay people from 35 countries. People who have such experiences are more likely to also show signs of REM sleep intrusion: 47% of those with near-death experiences had REM intrusion, compared with 26% of those who had unusual experiences that did not meet the threshold for a near-death experience and 14% of those with no such experiences. This link remained strong after adjusting for age, gender, location, employment, and perceived danger; people with REM intrusion were nearly three times as likely to report a near-death experience.
PeerJ
January 1, 2019
Daniel Kondziella, Markus Harboe Olsen, Coline L Lemale et al.
17 citations
People who experience migraine with aura are more than twice as likely to report a near-death experience (NDE) as those without migraine aura. In a sample of 1,037 adults from 35 countries, 13.0% of those with migraine aura reported an NDE compared to 6.1% of those without, an odds ratio of 2.33 after adjusting for age and gender. This association indirectly supports the idea that NDEs involve rapid eye movement (REM) sleep intrusion, a feature also linked to migraine with aura. The finding may relate to spreading depolarization, a brain wave pattern that occurs both in migraine aura and at the end of life.
Brain : a journal of neurology
June 12, 2025
Marwan H Othman, Attila Géry Toury-Puel, Karen Irgens Tanderup Hansen et al.
7 citations
In a double-blind, placebo-controlled trial, 50 intensive care unit patients with acute disorders of consciousness after brain injury received apomorphine, methylphenidate, or placebo. Automated pupillometry measured pupillary responses to verbal commands; neither drug significantly increased these responses overall. However, 20% of patients showed improved clinical arousal at least once after drug administration, with methylphenidate linked to more arousal events than placebo. Patients with greater baseline pupillary responsiveness were more likely to show arousal, suggesting this may predict stimulant effects. No adverse events occurred. The findings need replication but may guide future trials on consciousness recovery.
bioRxiv Preprint Server
October 21, 2019
Daniel Kondziella, Markus Harboe Olsen, Coline L. Lemale et al.
7 citations
preprint
Near-death experiences (NDE) are poorly understood but may involve rapid eye movement (REM) sleep intrusion, a feature of narcolepsy. Because migraine with aura is linked to narcolepsy and REM abnormalities, this study tested whether NDE are more common in people who have migraine with aura.
BMJ open
July 28, 2025
Trine Hjorslev Andreasen, Markus Harboe Olsen, Christian Gluud et al.
2 citations
Cortical spreading depolarisation (SD) is a pathological wave of brain cell activity that occurs frequently after severe acute brain injury and can worsen damage by reducing blood flow and increasing energy demand. Ketamine appears to inhibit SDs in laboratory and patient studies. The KETA-BID trial is a randomized, blinded feasibility and pilot study testing S-ketamine for SDs in adults undergoing surgery for traumatic brain injury, aneurysmal subarachnoid hemorrhage, or spontaneous intracerebral hemorrhage. Participants who develop SD clusters receive either continuous S-ketamine or placebo, with dosing adjusted based on SD occurrence. The primary outcome is SDs per hour after randomization. The trial will provide insight into SD and ketamine's clinical effects, potentially offering a new treatment.