Near Death Studies - Consciousness After Death

In summary, ketamine produces a near-death experience with some of the same features as the real thing, but it is not conclusive proof that consciousness persists after death.
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  • #2
I don't think it is bogus. I myself had a near death experience, and would love to see scientific studies done to gather evidence. We don't know what consciousness IS, and it could be a huge leap for man to understand that.
 
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  • #3
Ms Music said:
I don't think it is bogus. I myself had a near death experience, and would love to see scientific studies done to gather evidence. We don't know what consciousness IS, and it could be a huge leap for man to understand that.

Care to elaborate on your experience?

I would really like to hear what happened to induce such an 'experience'
 
  • #4
I had passed out and hit my head on concrete. I didn't have one of the "elaborate" stories that many books have written about, but I was going towards the light, and a voice commanded "GO BACK, it is not your time". Then I woke up with everyone surrounding me, an "aww shucks" kind of feeling that I was back on earth, and then the pain hit... Probably only about 20 seconds that I was out.

I do remember back in college, in psych we talked about being able to electrically stimulate a part of the brain to create the "light at the end of the tunnel" syndrome. But I think there is much more to be learned than that experiment alone.
 
  • #5
From skepdic.com
According to Susan Blackmore, vision researcher Dr. Tomasz S. Troscianko of the University of Bristol speculated:

If you started with very little neural noise and it gradually increased, the effect would be of a light at the centre getting larger and larger and hence closer and closer...the tunnel would appear to move as the noise levels increased and the central light got larger and larger...If the whole cortex became so noisy that all the cells were firing fast, the whole area would appear light. (Blackmore 1993: 85)

Blackmore attributes the feelings of extreme peacefulness of the NDE to the release of endorphins in response to the extreme stress of the situation. The buzzing or ringing sound is attributed to cerebral anoxia and consequent effects upon the connections between brain cells (op. cit., 64).
Blackmore, Susan J. Dying to Live: Near-death Experiences, (Buffalo, N.Y. : Prometheus Books, 1993).
Dr. Karl Jansen has reproduced NDEs with ketamine, a short-acting hallucinogenic, dissociative anaesthetic.

The anaesthesia is the result of the patient being so 'dissociated' and 'removed from their body' that it is possible to carry out surgical procedures. This is wholly different from the 'unconsciousness' produced by conventional anesthetics, although ketamine is also an excellent analgesic (pain killer) by a different route (i.e. not due to dissociation). Ketamine is related to phencyclidine (PCP). Both drugs are arylcyclohexylamines - they are not opioids and are not related to LSD. In contrast to PCP, ketamine is relatively safe, is much shorter acting, is an uncontrolled drug in most countries, and remains in use as an anaesthetic for children in industrialised countries and all ages in the third world as it is cheap and easy to use. Anaesthetists prevent patients from having NDE's ('emergence phenomena') by the co-administration of sedatives which produce 'true' unconsciousness rather than dissociation.*

According to Dr. Jansen, ketamine can reproduce all the main features of the NDE, including travel through a dark tunnel into the light, the feeling that one is dead, communing with God, hallucinations, out-of-body experiences, strange noises, etc. This does not prove that the NDE is nothing but a set of physical responses, nor does it prove that there is no life after death. It does, however, prove that an NDE is not compelling evidence for belief in either the existence of a separate consciousness or of an afterlife.
 
  • #6
And yet, neurophysiological processes must play some part in NDE, because NDE-like experiences can be induced through electrical “stimulation” of some parts of the cortex in patients with epilepsy,8 with high carbon dioxide levels (hypercarbia)9 and in decreased cerebral perfusion resulting in local cerebral hypoxia, as in rapid acceleration during training of fighter pilots,10 or as in hyperventilation followed by Valsalva maneuver.11 Also NDE-like experiences have been reported after the use of drugs like ketamine,12 LSD,13 or mushrooms.14 These induced experiences can sometimes result in a period of unconsciousness, but can at the same time also consist of out-of-body experiences, perception of sound, light or flashes of recollections from the past. These recollections, however, consist of fragmented and random memories unlike the panoramic life-review that can occur in NDE. Further, transformational processes are rarely reported after induced experiences. Thus, induced experiences are not identical to NDE.

http://www.iands.org/research/impor...ommel_m.d._continuity_of_consciousness_3.html
 
  • #7
Cool. Both of those posts have excellent information! And no, it definitely doesn't prove anything for or against NDEs. But me PERSONALLY, I do believe now that we have souls. I don't know if the OP wants to wander into the realm of Remote Viewing, but I believe they are all somehow interconnected. I believe there could possibly be a "button" in the brain that can be "pushed" with drugs (above listed), electrical stimulation, or like me, trauma, to make the soul exit the body. And I think it is possible that if remote viewing is REAL, (well, a few governments have definitely done a LOT of testing on it, that says something to its validity) that these people are capable of "pushing their own button" to make the soul leave the body. Can anything like that EVER be proved? I have no idea. But I would like to see science try.
 
  • #8
Ms Music said:
... And I think it is possible that if remote viewing is REAL, (well, a few governments have definitely done a LOT of testing on it, that says something to its validity) that these people are capable of "pushing their own button" to make the soul leave the body. Can anything like that EVER be proved? I have no idea. But I would like to see science try.

The fact that governments would expend taxpayers money in something says nothing about the validity of the idea.
Experiences made with astronauts and people inside nuclear submarines under the arctic ice revealed results not very different than those due to chance.
 
  • #9
CEL said:
The fact that governments would expend taxpayers money in something says nothing about the validity of the idea.
Very true, very true. And just because you read books on it and see documentaries on tv doesn't mean its valid either. They are always jaded in one way or another. So my thinking it has some validity is my naive understanding of what went on in that program. I won't say it IS 100% valid, but I won't say it is bunk either. :wink:


CEL said:
Experiences made with astronauts and people inside nuclear submarines under the arctic ice revealed results not very different than those due to chance.

I hadn't heard about that one. But it takes me back (again) to psychology where we did a predictability test by flipping a coin 10 times and guessing what it would be. Some people predominantly got 90%. (I always get 40%)

But I am dragging this off topic, sorry! I will say no more about remote viewing unless Gold Barz wants to...
 
  • #10
http://en.wikipedia.org/wiki/Dimethyltryptamine#Speculations

Several speculative and as yet untested hypotheses suggest that endogenous DMT, produced in the human brain, is involved in certain psychological and neurological states. As DMT is naturally produced in small amounts in the brains and other tissues of humans, and other mammals, some believe it plays a role in promoting the visual effects of natural dreaming, and also near-death experiences and other mystical states. A biochemical mechanism for this was proposed by the medical researcher J. C. Callaway, who suggested in 1988 that DMT might be connected with visual dream phenomena, where brain DMT levels are periodically elevated to induce visual dreaming and possibly other natural states of mind.[11]

Dr. Rick Strassman, while conducting DMT research in the 1990s at the University of New Mexico, advanced the theory that a massive release of DMT from the pineal gland prior to death or near death was the cause of the near death experience (NDE) phenomenon. Several of his test subjects reported NDE-like audio or visual hallucinations. His explanation for this was the possible lack of panic involved in the clinical setting and possible dosage differences between those administered and those encountered in actual NDE cases.

Ethical concerns do not allow for the testing of this hypothesis in humans, as the biological samples must come from the living human brain.

That could be another possibility for the visual experience people report after death
 
  • #11
The one thing I always wondered is, when people die, leave the body, see other people they knew, jesus, or angels; do they see clothes on these people? When you see your grandma, do you see her face, just sense her presence, just here her voice? Some people claim seeing people wearing clothes and all. If this is the case, then I would say that what those people saw came from their own brain and its memory because a soul couldn't wear clothes.
 
  • #12
Conclusion: It ain't heaven if you can't see grandma naked? :biggrin:

Why would you even see bodies? Why would you see? Even if we assume that the mind somehow exists beyond the brain and after death, anything that you experience would by definition all be in your mind.
 
  • #13
Ivan Seeking said:
Conclusion: It ain't heaven if you can't see grandma naked? :biggrin:

Why would you even see bodies? Why would you see? Even if we assume that the mind somehow exists beyond the brain and after death, anything that you experience would by definition all be in your mind.

Maybe when your "soul" leaves the body, you can see through the eyes of alive people. That would be cool. You could like see through everyones eyes at once.
 
  • #14
Well, I think we are getting way off-topic now. :smile:
 
  • #15
I attended a lecture by a guy doing research into this at Cambridge. He said he had managed to achieve the same in patients as NDE by using various tranquillisers. Pity it was about 10 years ago and I can't remember most of it. Suffice to say he speculated that this was nothing more than a state readily achievable given certain stimuli conditions or lack there of. Probably the fact that it relates to our images of death is some sort of coincidence, but I can see how not fearing death would be a comfort to people anyway.
 
  • #16
Schrodinger's Dog said:
I attended a lecture by a guy doing research into this at Cambridge. He said he had managed to achieve the same in patients as NDE by using various tranquillisers.Pity it was about 10 years ago and I can't remember most of it. Suffice to say he speculated that this was nothing more than a state readily achievable given certain stimuli conditions or lack there of.
Would he be Dr. Karl Jansen, that I mentioned in my previous post?
Probably the fact that it relates to our images of death is some sort of coincidence, but I can see how not fearing death would be a comfort to people anyway.
I don't think it is a coincidence. The images are real. The fact that people associate them to the afterlife is that in western culture heaven is thought to be a place of much light.
The fact that many people have described their experiences and that it has been amply reported, is another factor that induces people to think they have visited the other side.
 
  • #17
CEL said:
Would he be Dr. Karl Jansen, that I mentioned in my previous post?

Yes indeed that's the fellow, he was only a PhD student back then and that was his thesis. Interesting lecture, ketamine, that's it. He got his Dphil from Oxford as well. Memory burp.

Sorry I only skimmed your post.
 
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  • #18
Hallucination

I had this sort of hallucination and thought I visited the other side. Quite a rush.
 
  • #19
CEL said:
From skepdic.com

I've heard that deaf people have had NDE. How would the noise figure into their experience?
 
  • #20
moonstroller said:
I've heard that deaf people have had NDE. How would the noise figure into their experience?

The noise in the neurons is visual, not auditive.
 
  • #21
Some documentation of this NDE phenomona show people leaving the body, traveling to another location and seeing events that were later verified. If the effect is local to the brain, how were these people able to reveal information that exists in another location?
 
  • #22
CEL said:
The noise in the neurons is visual, not auditive.

I have tinnitus. I hear noise not see it.
 
  • #23
moonstroller said:
Some documentation of this NDE phenomona show people leaving the body, traveling to another location and seeing events that were later verified. If the effect is local to the brain, how were these people able to reveal information that exists in another location?

How reliable is this information, has a study been done? I mean it's possible that the auditory area of the brain is feeding the brain with stimulus, even close to the point of death, and like we do in dreams it is constructing a visual record according to outside stimulus. In order to test this you'd have to see just how reliable these witness testimonies are, and whether the information could have been picked up pre-op or at the time of the NDE.
 
  • #24
moonstroller said:
I have tinnitus. I hear noise not see it.

Noise was used in the sense of an unwanted fluctuation in the firing of the neurons. This is interpreted by the brain as light. It is similar with sonorous noise, that is an unwanted fluctuation of the sound signal.
 
  • #25
moonstroller said:
Some documentation of this NDE phenomona show people leaving the body, traveling to another location and seeing events that were later verified. If the effect is local to the brain, how were these people able to reveal information that exists in another location?

This can be a cultural phenomenon. New agers claim that the soul can travel astrally away from the body and see things very far away, or simply see the inanimate self body laying on a bed. The media has diffused it so much that hardly anybody has never heard of it. In a state of stress one can hallucinate and see things that are in his cultural unconscious.
One way to avoid contamination of stories has been developed by University of North Texas professor Dr. Jan Holden.* She designed an experiment in which a laptop computer that opens flat hangs from the ceiling with the screen facing away from the floor. Her husband developed a software program that produces a series of animations. If a patient claims to have been floating above her body on the operating table, then she ought to have seen the computer screen and be able to report on what she saw. Dr. Bruce Greyson has apparently been using this protocol for a few years but so far has not reported anything of interest.
 
  • #26
Or you could do that, thanks CEL. :smile:
 
  • #27
Near death experiences have also been repeatedly experienced by pilots undergoing high-g centrigugal training. The blood rushes from their brain causing a deficiency of oxygen, which in turn causes hallucinations almost always attributed as similar to NDE's (tunnel, out-of-body experiences, light).
 
  • #28
Just out of curiosity, do you guys believe quantum mechanics? That matter has particle and wave properties?
 
  • #29
Quantum mechanics is not a matter for belief or not; it is a scientific model for the quantum world that correctly predicts the dynamics observed at very small scales. And yes, matter can act like either particles or waves; that is a fact.

How is this related to the discussion?
 
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  • #30
Ms Music said:
Just out of curiosity, do you guys believe quantum mechanics? That matter has particle and wave properties?

It's not a matter of believing its a matter of empirical evidence, it does seem to fit experimentation and to conform to mathematical models, no matter how bizarre they seem.

Now interpretation, that is a different matter, some interpretations have no evidence in experimentation, so although they may be useful to gain an understanding of the quantum, to believe they are correct is currently a belief. There tends to be where the issue lies atm, as none of the interpretations are without drawbacks. We are somewhat stumbled by the behaviour of the quantum, not to say we cannot describe it, but the finer points, they are somewhat open to question.
 
  • #31
Strictly speaking, interpretations are not a part of the model.
 
  • #32
Ivan Seeking said:
Strictly speaking, interpretations are not a part of the model.

True, but I was outlining where the differences of opinion lie. The model itself is pretty much agreed upon.
 
  • #33
Ivan Seeking said:
Quantum mechanics is not a matter for belief or not; it is a scientific model for the quantum world that correctly predicts the dynamics observed at very small scales. And yes, matter can act like either particles or waves; that is a fact.

How is this related to the discussion?

That possibly the wave nature of a particle is the same (in a way) as the consciousness is of a human. I think that analogy was even made in one of the articles listed by the OP. I think the thought of a human having a soul is too often seen as having religious connotations, so not accepted as a posibility in the scientific world.
 
  • #34
Ms Music said:
That possibly the wave nature of a particle is the same (in a way) as the consciousness is of a human. I think that analogy was even made in one of the articles listed by the OP. I think the thought of a human having a soul is too often seen as having religious connotations, so not accepted as a posibility in the scientific world.

But we can at least do experiments on a wave function, we can see at least that where a wave is not, and how it's represented by our experiments, even if we cannot measure it directly. This is not the same as a soul, where we cannot measure where it is or where it is not, because it is not anywhere measurable at any point, nor indirectly so.

It's not wise to confuse science with those things that have no evidence; just as it is not wise to make the assumption that science disagrees with religion: it does not, they are not able to meet by their nature. Philosophically yes, they have common ground, but there hasn't been a schism between science and religion since Galileo and Copernicus claimed the Earth went round the sun. Even evolution wasn't at odds with religion in any way that we can call science.

Science can never claim something does not exist, it can only claim that given evidence we know that it has no evidence that it exists. Science does not claim the soul does not exist, or God, or the Flying Spaghetti Monster. It simply has no remit to comment without some form of evidence.
 
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  • #35
Pardon me for interrupting. I will stay out of the discussion now.
 
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