Sunday, November 27, 2022

Thoughts about near death experiences

CONTEXT
This is one of those topics where the human brain-mind likes to run wild. Most humans dislike ambiguity and incomplete stories. In the face of ambiguity, incomplete facts and contradictory narratives, complexity and the like, the human mind tends to fill in gaps, sanitize contradictions to tidy up cognitive dissonance and simplify complexity. We unconsciously often or usually do things to make the world seem to be safer for self-esteem, self, family and tribe interests and moral authority. Often times the reality our brain-minds create significantly diverges from actual reality, whatever that might be. 

Now, on to the main event:

On near death experiences (NDEs)
(Twilight zone music tinkling 
gently in background)


In 2014, one of the first papers that tried to prove that NDEs were real world experiences (objective realities) separate from brain activity (a non-physical mental event, e.g., activity of an immaterial soul) rather than experiences generated by the brain-mind. That was called the AWARE study. One expert, Steve Novella at Neurologica blog, commented that the study failed. Novella discusses a second attempt, the AWARE II study, to generate evidence to support or refute the objective reality of NDEs:
The notion of near death experiences 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 [cardiopulmonary resuscitation], they were eventually recovered and lived to tell the tale. About 20% of people in this situation will report some unusual experience. .... 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 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.
A 2018 research paper described NDEs like this:
Near-death experiences (NDEs) are complex experiential episodes that occur in association with death or the perception that it is impending (Moody, 1975; Greyson, 1983). Prospective studies with cardiac arrest patients indicate that the incidence of NDEs vary between 2–18% depending on what criteria are used to determine them (Parnia et al., 2001; Van Lommel et al., 2001; Schwaninger et al., 2002; Greyson, 2003). Although there is no universally accepted definition of the NDE, common features include feelings of inner-peace, out-of-body experiences, traveling through a dark region or ‘void’ (commonly associated with a tunnel), visions of a bright light, entering into an unearthly ‘other realm’ and communicating with sentient ‘beings’ (Moody, 1975; Ring, 1980; Greyson, 1983; Martial et al., 2017).
Not surprisingly, some people are looking for, and want to find, a spiritual or supernatural explanation. A 2019 research paper, Near-Death Experiences are Not Evidence for Either Atheism or Theism, comments:
The failure to secure replicable positive results in near-death experience (NDE) target-identification experiments does not establish the nonexistence of any spiritual realms, but it does serve to substantially challenge positive arguments in favor of the existence of spiritual realms from NDE reports. For if veridical paranormal perception occurs during out-of-body experiences (OBEs) or NDEs, why the failure to find it in all of the controlled experiments that have been undertaken to document it thus far? Various explanations can be put forward, but in the absence of ad hoc maneuvering, the hallucination hypothesis predicts only one set of possible results: the results actually found. Until the time that properly controlled NDE target-identification experiments yield replicable positive results, they will take their place as historical curiosities akin to similarly unsuccessful direct tests of survival after death. While some eagerly await the results of the follow-up AWARE II study (which is recruiting subjects until 2020), at the moment the unsuccessful history of comparably easier-to-implement research into the paranormality of non-near-death OBEs does not bode well for those results.
Despite the inconclusive data, some people firmly believe that NDEs are true spiritual experiences that reflect actual reality instead of something the brain-mind created. The lead researcher on the AWARE and AWARE II studies, Sam Parnia, seems to be one of those people. Novella comments:
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.
In summary, it is reasonable to believe that NDEs are just what a stressed brain-mind sometimes generates. Evidence available so far indicates that NDEs do not to arise from a soul or other spiritual source, but since such things are supernatural, by definition, humans can never detect or characterize them. I suppose there could be a non-supernatural source of NDEs that science eventually comes to detect, characterize and at least partly understand. Then we will probably come to a better state of understanding. 

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