The notion of near death experiences (NDE) have fascinated people for a long time. The notion is that some people report profound experiences after waking up from a cardiac arrest – their heart stopped, they received CPR, they were eventually recovered and lived to tell the tale. About 20% of people in this situation will report some unusual experience. Initial reporting on NDEs was done more from a journalistic methodology than scientific – collecting reports from people and weaving those into a narrative. Of course the NDE narrative took on a life of it’s own, but eventually researchers started at least collecting some empirical quantifiable data. The details of the reported NDEs are actually quite variable, and often culture-specific. There are some common elements, however, notably the sense of being out of one’s body or floating.

The most rigorous attempt so far to study NDEs was the AWARE study, which I reported on in 2014. Lead researcher Sam Parnia, wanted to be the first to document that NDEs are a real-world experience, and not some “trick of the brain.” He failed to do this, however. The study looked at people who had a cardiac arrest, underwent CPR, and survived long enough to be interviewed. The study also included a novel element – cards placed on top of shelves in ERs around the country. These can only been seen from the vantage point of someone floating near the ceiling, meant to document that during the CPR itself an NDE experiencer was actually there and could see the physical card in their environment. The study also tried to match the details of the remembered experience with actual events that took place in the ER during their CPR.

You can read my original report for details, but the study was basically a bust. There were some methodological problems with the study, which was not well-controlled. They had trouble getting data from locations that had the cards in place, and ultimately had not a single example of a subject who saw a card. And out of 140 cases they were only able to match reported details with events in the ER during CPR in one case. Especially given that the details were fairly non-specific, and they only had 1 case out of 140, this sounds like random noise in the data.

The primary purpose of a research study like this is to distinguish among various alternative hypotheses. In the case of NDEs there are two main hypotheses. One is that NDEs represents brain activity that occurs sometime between the person having CPR and when they ultimately wake up and tell their story. The other is that NDEs represent a genuine non-physical mental event that happens close to death but independent of the body. AWARE did not provide any evidence to distinguish these hypotheses.

Since then Parnia has been working on AWARE-II, with some tightened protocols. One is that they only use subjects who underwent CPR in a hospital, to control for the quality of the CPR. We only have preliminary reports of the data so far, which has not undergone peer-review or been published. The results will be presented at the American Heart Association’s Scientific Sessions 2022 taking place in Chicago on November 6. We do have some details from interviews with Parnia, however.

“A key finding was the discovery of spikes of brain activity, including so-called gamma, delta, theta, alpha, and beta waves up to an hour into CPR.”

That’s interesting, and if anything supports the brain activity hypothesis. Reports that people are having NDEs while having no brain activity are not supported by data, for two reasons. The first is that there is no confirmation of when the memories formed. They could have formed anytime during the recovery period until the patient was fully awake. That is the reason Parnia wants to tie the experiences to the emergency room during CPR, to eliminate the possibility that the memories formed later. But he was unable to do that in AWARE and so far there is no mention of that in AWARE II. But you would have to couple evidence that the memories formed during CPR with convincing evidence for lack of brain activity at the same time. Finding spikes of brain activity during CPR would be strike two for the hypothesis that NDEs represent mental activity separate from brain activity.

For background, CPR typically produces about 20% of the perfusion that normal heart function would produce. This is enough to keep the brain alive, but not to allow for full consciousness. But, even within a hospital setting, CPR will be performed with variable skill. Further, there are variations in the vasculature of the brain. Presumably, someone with a cardiac arrest likely has vascular disease which may include cerebrovascular disease. Therefore the actual amount of perfusion of brain tissue may be quite variable in patients undergoing CPR. Perhaps in 20% of cases there is just enough brain perfusion for some parts of the brain to function, enough to create an altered awareness.

I don’t even know if this is a necessary hypothesis, because it has not been established that the memories of alleged NDEs are formed during the near death experience itself. But even if they were, the evidence supports the notion that the experiences result from reduced but non-zero brain function. AWARE II now supports that interpretation.

There are no reports of any evidence arising from AWARE II that places the experience in the ER, such as subjects reporting what was on the cards placed on high shelves. Parnia has reverted to characterizing the experiences themselves. He says:

“These lucid experiences cannot be considered a trick of a disordered or dying brain, but rather a unique human experience that emerges on the brink of death,” says Parnia.

But why? What does he even mean by a “trick of a dying brain”? Wouldn’t what is being reported be consistent with partial brain function during reduced perfusion from CPR? I get the sense that Parnia is desperate to interpret his results as finding something new and unique, but I’m just not seeing it. It also seems like an example of the Texas Sharpshooter Fallacy. The original intent of the AWARE studies was to demonstrate that NDE memories are formed during CPR and are not the result of brain activity. He has proven neither – there is no evidence from AWARE or reported so far from AWARE II that links the memories to the time of the CPR. Further, it seems there is evidence of brain activity during CPR.

So – NDEs are likely just what the brain does in about 20% of cases during CPR. That is the simplest explanation of all the data. Trying to tease meaning out of the details of the experiences themselves is a slippery endeavor. Those memories are highly contaminated by the time they are reported, by nothing else than the culture in which they occur. Most people now know what an NDE is supposed to be like, just like they know what an alien abduction is supposed to be like. This means that subjective reporting has to be taken with a grain of salt. What we need is hard evidence, and the hard evidence points to a brain phenomenon.