Friday, September 30, 2011

There is nothing paranormal about near-death experiences.

Mobbs and Watt argue that neuroscience can explain seeing bright lights, meeting the dead, or being convinced you are one of them, suggesting that there is nothing paranormal about these experiences. Instead, near-death experiences are the manifestation of normal brain function gone awry, during a traumatic, and sometimes harmless, event. They engage several basic features of near death experiences (awareness of being dead, out of body experiences, tunnel of light, meeting deceased people, euphoric emotions) and note the brain regions whose perturbation by electrical stimulation or ischemic strokes can induce each phenomenon. Some can be observed in normal individuals under particular conditions of sensory stimulation (I've done posts on the Blanke experiments on out of body experiences). Their arguments are of the "may be" or "could be" sort, and their summary seems to to be particularly vague hand waving...
The near-death experience is a complex set of phenomena and a single account will not capture all its components. One recent theory is that the basic arousal systems beginning in the midbrain may account for many of the components of the near-death experience. Of interest is the locus coeruleus, a midbrain region involved in the release of noradrenaline. Noradrenaline is known to be involved in arousal related to fear, stress, and hypercarbia, and is highly connected to regions that mediate emotion and memory, including the amygdala and hippocampus. Indeed, stimulation of the noradrenaline system has been shown to enhance and consolidate memory, and plays a critical role in the sleep-wake cycle, including REM sleep. Along with basic midbrain systems, such as the periaqueductal gray, a region involved in opioid analgesia and basic fear responses, and the ventral tegmental area, which is a core dopamine reward area, the noradrenaline system may be part of a basic set of systems that directly or indirectly evoke positive emotions, hallucinations and other features of the near-death experience.

Taken together, the scientific evidence suggests that all aspects of the near-death experience have a neurophysiological or psychological basis: the vivid pleasure frequently experienced in near-death experiences may be the result of fear-elicited opioid release, while the life review and REM components of the near-death experience could be attributed to the action of the locus coeruleus- noradrenaline system. Out-of-body experiences and feelings of disconnection with the physical body could arise because of a breakdown in multisensory processes, and the bright lights and tunneling could be the result of a peripheral to fovea breakdown of the visual system through oxygen deprivation. A priori expectations, where the individual makes sense of the situation by believing they will experience the archetypal near-death experience package, may also play a crucial role. If one challenge of science is to demystify the world, then research should begin to test these and other hypotheses. Only then will discussion of near-death experiences move beyond theological dialogue and into the lawful realm of empirical neurobiology.

7 comments:

  1. "neuroscience can explain" will be next century's "old wives tales" ... some truth, but humorously off-base.

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  2. Anonymous12:06 AM

    neuroscience is fact douche bag. God, Jesus, religion and the bible are wives tales believed by weak people and those desperately in denial about their own mortality.

    One simple question I pose to people. Why the hell cant you remember the 14 billion years before you were born? Why? You didnt exist...you were nothing. Death?
    Exactly the same state.

    Now GTFO.

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  3. Anonymous2:25 PM

    Reply to the above comment.

    Your comment is so weak. It is not necessarly about religion or Jesus, you can believe in spirit without Jesus...

    Now to answer your question, when you have your life on earth, you are in your body and your brain is the organ that makes you able to have feelings, etc. It does not mean that you don't have a spirit.

    Your life starts on earth but it doesn't mean it ends on earth.

    It's funny how anti-religion people are violent and aggressive because they are so afraid to be wrong that they want to make fun of people who believe.

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  4. Anonymous8:16 PM

    The funny thing is that science comes up with provable theories and the religious nuts try to shoot it down. Religion has nothing that has been proven EVER, yet they believe it without even thinking about the alternative. Science never goes away, yet religions come and go with the times. 1000 years from now, scientology will be the normal religion and everything else will be silly and no one will know why anyone ever believed the "crazy" old religions, like the greek gods are to us now. Oddly enough, science will still be around and even though there is proof, the religious people will still not believe it.

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  5. The "religion" expressed in the quoted passages of the post is the religion of scientism. As soon as you begin examining the many reliable, verifiable reports of extrasensory details provided by NDE patients, the whole scientistic explanation here goes out the window

    As anonymous put it, scientism will, in a century's time (actually, I suspect it will be by the middle of this century) be considered just as much of an "old husband's tale" (I think the masculine pronoun is apt - go to any debunkers forum and count the number of females - I even would accept McGilchrist's brain-based explanation for this) as most of the superstitions that anonymous refers to.

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  6. Anonymous12:30 PM

    There it is, science and religion, the great divide. Both have always been subject to peer review, as they should. When either is used as an attempt to gain power or prestige, a concept can be made popular prior to this review and the popularity will always outweigh the review. Why? Because people are easily convinced and will feel the need to convince others in order to reconfirm their reason for having been convinced. So, we have popular science and popular religion. Just groups of people trying to make sense of their individual existence. E.J.

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  7. Popular science like that of Dawkins, Crick, and Coyne?

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