"Doctors find explanation for near-death experiences": This was the title of the BR24 newsletter on March 21, 2022. Similar headlines appeared in many other media. Apparently, the scientific explanation for near-death experiences had finally been found: Shortly before death, there is an increase in gamma waves in the brain, which is typical of vivid dreams and memories. So do we have to give up the hope that near-death experiences may portend life after death?
The study
The reason for the reports was a study by neurosurgeons from the University of Tartu in Estonia. They hooked up the brain of an 87-year-old epileptic to an EEG monitor when he went into cardiac arrest. The device remained connected for 30 seconds after his death. It recorded an increase in gamma waves just before the heart stopped and just after. A similar amplification of gamma waves had previously been measured in rats in induced cardiac arrest.
So, does it follow that the religious and spiritual expectations associated with near-death experiences are baseless? One reason why near-death experiences are fascinating is because they can allegedly occur even when there is no longer any brain activity. If this is true, then near-death experiences show that the spirit can detach from the body, possibly even surviving its death. However, the current study proves that this is not the case.
In earnest? Have the Estonian researchers actually demonstrated that brain activity is underlying near-death experiences? Meaning, that consciousness is always linked to brain activity, even in near-death experiences?
Voices on the study from the German “Netzwerk Nahtoderfahrung”
“Netzwerk Nahtoderfahrung”, the German branch of IANDS, took up the topic in its April 2022 newsletter. The network chairman Joachim Nicolay, the neurologist Wilfried Kuhn and the journalist Werner Huemer (Thanatos TV), who extensively quoted the Swiss death researcher Reto Eberhard Rast, took a stand. Among other things, they pointed out the following:
The 87-year-old epileptic was not able to report any near-death experience because he died after the measurements. So we only have the medical data from this case. And they don't even show a flat line EEG, as one would actually expect with brain death. That's because death occurred during an epileptic seizure.
What was measured? The dying brain of an epileptic receiving antiepileptic drugs during an epileptic seizure. It can therefore be assumed that the measured gamma waves are related to epilepsy. Because epileptic seizures and antiepileptic drugs also lead to increased gamma waves. However, this gamma increase does not lead to conscious experiences in epileptics: No patient has ever reported a near-death experience or a state of lucid consciousness after an epileptic seizure. In fact, epileptics can't remember anything after their seizure because they were unconscious - gamma waves or not.
So why, in this particular case, should gamma waves be used to explain a near-death experience that we don't even know if the patient actually had?
There is another reason why it is unlikely that the measurements on this one patient could explain near-death experiences in general: near-death experiences can also occur under physiologically completely different conditions. For example, in perfectly healthy people in fear of death, under the influence of hallucinogenic drugs, or in a fall in the mountains in the seconds or fractions of a second before the injury. But if near-death experiences occur under physiologically completely different conditions: how can the specific physiological conditions of an 87-year-old epileptic with no known near-death experience explain near-death experiences in general?
So that an increase in gamma waves causes the life flashback reported by near-death experiencers is pure speculation. Experiments with rats tortured to death cannot provide any information about this either. Because rats can report near-death experiences neither dead nor alive.
Bruce Greyson, Pim van Lommel and Peter Fenwick on the Topic
A commentary on the Estonian neurologists' study has appeared on the IANDS website, written by near-death researchers Bruce Greyson, Pim van Lommel and Peter Fenwick. They emphasize that what the authors of the study themselves do claim is one thing - what the media made of it is another.
Do the study authors claim to have solved the mystery of near-death experiences? Not at all: They call it speculation that the gamma waves they measured could serve as an explanation for near-death experiences. Only the media gave the impression that this was the ultimate explanation of near-death experiences. And they did so against the will of the authors. Because they expressly emphasize that their study should not be generalized: The gamma waves in the brain of the 87-year-old, they restrict, could be related to his traumatic brain injury, the medication administered, the lack of oxygen and the increased carbon dioxide content in his blood.
But that's not all: It is possible that the measured gamma waves, at least in part, do not even come from the brain: The results could have been influenced by waves from muscle contractions that were incorrectly measured.
Above all, however, a closer look reveals that the increase in gamma waves after the cardiac arrest, which the media claimed, was not even measured by the scientists. What they noticed was not an increase, but on the contrary a reduction in gamma waves. Only the relative proportion of gamma waves was increased compared to alpha, beta and delta waves. And that's only because the latter were reduced faster than the also receding gamma waves.
So much ado about nothing? In any case, the authors of the study were well advised to exercise caution in interpreting their data. And all the more so because they obviously knew the current state of research only insufficiently: In their study they write that there has never been any systematic research on brain activity during the dying process. In contrast, Greyson, van Lommel and Fenwick state: Clinical experience and research on the dying process has been around for decades.
And these decades of research have shown that brain activity typically declines in the eight seconds following a cardiac arrest, to flat line EEG around 18 seconds. Similar results have been reported from cases where brain activity was measured during cardiac arrest, such as during surgery. But with a flat line EEG, we don't have any gamma activity either. And reports of near-death experiences that took place during a flat line EEG do exist. Arguably the best-documented case is that of Pam Reynolds.
Apparently there are near-death experiences that happen at a point in time when no brain activity can be measured. At least none of the brain activities that, according to the current state of research, are a prerequisite for experiences of high coherence and complexity – and that's what near-death experiences are. In other words, we are faced with a conundrum. The Estonian study has not changed this.
Nice try. When's the next one?
Joachim Nicolay already stated in 2016: The news that the mystery of near-death experiences has now been solved has been appearing again and again in popular media for decades. Each time, a different physiological explanation is supposed to prove that it's just hallucinations. But if there were actually one scientifically proven explanation for near-death experiences, then you wouldn't have to keep coming up with a new explanation again and again.
So the controversy about the interpretation of near-death experiences cannot be ended that easily. The neurologist Jens Dreier may have heralded the next round in an interview with “Spektrum der Wissenschaft”. He says that 30 to 40 seconds after cardiac arrest, all brain activity is gone. But minutes later there is a huge wave of nerve cell discharges, comparable to a short circuit. In this emergency situation, the body releases drug substances, and these may be causing near-death experiences.
Dreier himself describes this conclusion as speculation. Whatever physiological facts the researchers may unearth, the question will always be: What do these facts explain and what do they not? And again and again the personal answer will depend on what you believe is possible. But that is more a question of worldview than one of facts.
What shouldn't be can't be
Our worldview narrows or widens our horizons. It determines which phenomena we consider relevant, or even acknowledge, and which we don't.
Materialists have strong motives for considering near-death experiences as irrelevant. Because near-death experiences go hand in hand with phenomena that modern science cannot explain: out-of-body experiences that subsequently turn out to be correct; telepathy; encounters with the deceased whose death was previously unknown. Dying persons and their loved ones can even share the same near-death experience – a neurobiologically inexplicable process (R. Moody et al., Glimpses of Eternity).
Neurobiological mechanisms can trigger near-death experiences. But to explain their complete process scientifically, including the paranormal side effects - nobody has managed that yet.
So if the ultimate scientific explanation for near-death experiences is presented in the media in the near future, you can confidently assume that these reports say more about the ideological prejudices and the time pressure of the journalists involved than about the near-death experiences themselves.
Sources
BR24, March 21, 2022 (in German): „Ärzte finden Erklärung für Nahtoderfahrungen“: https://www.br.de/nachrichten/deutschland-welt/aerzte-finden-erklaerung-fuer-nahtoderfahrungen,T0idJC2
Study „Enhanced Interplay of Neuronal Coherence and Coupling in the Dying Human brain“ (2022): https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8902637/
The Newsletter of the Netzwerk Nahtoderfahrung (Issue: April 2022) is available for members under https://netzwerk-nahtoderfahrung.org/.
Commentary of the near-death researchers Bruce Greyson, Pim van Lommel and Peter Fenwick regarding the study mentioned above: https://www.iands.org/1661-commentary-on-report-of-eeg-in-a-dying-human-brain.html
Interview with neurologist Jens Dreyer in Spektrum der Wissenschaft (in German) regarding the physiological basis of Near-death experiences (from a physicalist point of view): https://www.spektrum.de/news/tod-was-beim-sterben-im-gehirn-passiert/2043556?utm_source=pocket-newtab-global-de-DE
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