Near Death Experiences
"People have reported "near death experiences", or NDE's, over centuries and across cultures. The nature of them has historically been the territory of religion and philosophy. But now science has staked its claim in the discussion. And the questions are profound: where is consciousness produced, in the brain, or somewhere else? Can consciousness continue to exist even after the heart and brain have stopped working? Contributor Ashley Walters explores the science and the meaning of near death experiences. **This episode originally aired December 7, 2016"
Of course, one may listen closely to the episode and fail to find any mention of how"science" is "staking a claim" in the discussion. The piece is basically a book report.
The CBC program is a textbook case of the kind of muddle that surrounds the NDE issue. Time and again, the subject is claimed to have undergone "clinical death", yet somehow remembers something. The central paradox is, How can he remember anything when his brain has stopped functioning? It must be true that his "soul" somehow works without the brain.
This is all turns on a deliberate misuse of the term "clinical death", which does not involve cessation of brain function: merely cessation of heart beat and respiration. In the cited cases, even this is far from certain, since the subject is usually revived before medical assistance arrives (otherwise real death is the likely outcome). Certainly in the ambulance and even on the operating table, the patient is rarely instrumented to detect (or not detect) brain function. In any case, I am not aware of any case where brain function has actually ceased and the patient has revived. Even in cases of deep coma, there is some brain function. To put the case clearly: we don't have anyone coming back to tell us what it's like to be brain dead. There's a good reason for that, I think.
This removes the central mystery. There is certainly nothing stopping a person undergoing "clinical death" from having (or at least remembering) some kind of experience.
An important element in the NDE mythology is the "fact" that so many of these experiences have so much in common. The problem with this claim is that the "journalists" that write about the experience actually go out looking for the people who have that exact experience. The vast majority of people with a different experience (especially no experience at all) are passed over. You would think this would be a serious problem for the theory that we all pass on to another reality upon death when obviously most of us don't. In a word, it's cherry picking.
So there goes the second source of wonder. Some people have similar experiences when their heart stops. It's starting to seem to be a somewhat weaker challenge to the "conventional" idea that we need a brain to "be".
For those who are unfamiliar with the phenomenon of consciousness itself, the fact that people can hear what's going on while "blacked out" is remarkable. However it is a well established fact that the brain's auditory systems are alive and working even under general anesthesia - we just can't normally remember what we hear. In the unusual brain state of the "NDE", it is not to much of a stretch to assume that what the subject is hearing will be woven into whatever visions are remembered.
So what about the sensation of leaving the body? Well, you can ask this a different way. Why is it that we usually have the feeling that we are in our body? The familiar exception to this experience is the dream. Why is this not relevant?
The sensation of being "in" the body can be knocked out of action by, for example, a shortage of oxygen to that part of the brain. Feelings of being outside the body can be triggered by a variety of situations - you don't need to be "clinically dead". Feelings of euphoria and heavenly visions can also be attributed to release of endorphin in the brain - akin to a big shot of morphine released as an automatic response to the trauma that stopped the heart in the first place. It makes more sense to ask how the brain creates a vivid "trippy" dream rather than ask how the experience happens without the brain. While the brain still holds many mysteries, we are quite sure what parts of the brain are active when an "experience" is going on and what parts are necessary for that experience to be remembered. Why is it that we so casually set aside all this knowledge and embrace the idea that all these brain functions happen without the brain? Where is the evidence that the brain is not responsible for these experiences?
It should be noted that these "trippy" experiences (known as "peak experiences") happen to people who are in perfect heath and do not require "clinical death". Peak experiences are also notorious for fitting into a matrix of mythological interpretation that is familiar to the subject - such as "seeing God" or being "saved". The subject needs to be "primed" to find the right words to describe the experience.
What we are left with is claims that the disembodied soul went wandering around and learned things that could not have been otherwise learned. This is essentially a claim of a telepathic experience. In these cases, we have more theories available than wandering souls. The wandering soul hypothesis is, after all, a rather radical one. Following Carl Sagan, we demand extraordinary evidence for extraordinary claims. (Skepticism 101). What must we assume in order to be left with the conclusion that of telepathy is the only possible explanation?
- The subject is not lying. Lying is an ordinary behavour and does not require supernatural explanation.
- The subject perfectly remembers the experience. This is an odd assumption to make since we know that none of us has perfect memory and these subjects are specifically selected to have been recovering from a near-fatal trauma.
- Third party testimony (the gold standard in these fables) is accurately reported. The "witnesses" also are credited with perfect memory even though they themselves have usually been part of an extremely traumatic experience.
- We must ignore powerful confirmation bias acting to confirm the subjects belief that he has proven that death is not the end. Confirmation bias is the bane of serious scientific investigation. Why not a problem with amateur interpretation of a once-in-a-life-time experience?
What we are left with is lots of strange tales. The plural of anecdote is not evidence. We can't toss aside everything we know about the brain without compelling evidence. That's Sagan's rule.
But then all this fits nicely into the religious mythology of the culture. As stated in the outset of the piece, "all" religions teach that there is a life beyond death. Even if the subject doesn't believe this, the experience in question will tend to convince him otherwise. It's an available "explanation". He is more likely to be familiar with Christian mythology than neuroscience.
None of these points are addressed in the CBC piece, which is really nothing more than a pitch for another "New Age" book helping the credible to deny death and put the whole issue on the back burner pending the next boozy discussion over the camp fire.
My personal opinion is that the brain is necessary but not sufficient for consciousness. Consciousness critically depends on a social setting. We experience the world together. This is starkly evident when the individual is placed in a situation that departs widely from everyday experience., It makes perfect sense for the "self" to dissolve finally into a drug-assisted and muddled dream set in a comfortable mythical world. The story is told not only by the "subject" whose heart stopped for awhile, but by those around him who cooperate to keep the myth alive and authors who sell books to the gullible. It is that social matrix of ideas - right, wrong, good and bad - that lives on. These ideas don't need to reside in any one particular brain. When one brain goes dark, the "memes" live on.
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