Encyclopedia  |   World Factbook  |   World Flags  |   Reference Tables  |   List of Lists     
   Academic Disciplines  |   Historical Timeline  |   Themed Timelines  |   Biographies  |   How-Tos     
Sponsor by The Tattoo Collection
Near-death experience
Main Page | See live article | Alphabetical index

Near-death experience

A near-death experience (NDE) is the perception reported by a person who nearly died or who was clinically dead and revived. They are somewhat common, especially since the development of cardiac resuscitatation techniques, and are reported in approximately one-fifth of persons who revive from clinical death. The experience often includes an out-of-body experience.

Typically a near-death experience involves the sensation of floating above one's body and seeing the surrounding area, followed by the sensation of passing through a tunnel, meeting deceased relatives, encountering a being of light. There have also been accounts of patients seeing things they apparently could not have seen had they not been out of their bodies.

Table of contents
1 NDE as an afterlife experience
2 NDE as a naturalistic experience
3 Research
4 Further reading
5 External links

NDE as an afterlife experience

Many see near death experiences as an afterlife experience, and some accounts include elements that are most simply explained (see Occam's Razor) by an out-of-body consciousness. For example, one in one, a woman accurately described a surgical instrument she had not seen previously, as well as conversation that occurred while she was clinically dead. In another from the proactive Dutch NDE study[1], a nurse removed the dentures of an unconscious heart attack victim, and was asked by him after his recovery to return them. But researchers have been unsuccessful in running proactive experiments to establish out-of-body consciouness. There have been numerous experiments in which a random message was placed in a hospital in a manner that it would be invisible to patients or staff yet visible to a floating being, and thus far, no person experiencing a near death experience has been able to reproduce the message.

Nevertheless, the subjective reality of NDEs is well documented.

NDE as a naturalistic experience

Many see near death experiences as a purely naturalistic phenomenon.

One scientific hypothesis that attempts to explain NDEs was originally suggested by accounts of the side-effects of the drug Ketamine (see link to Dr. Karl Jansen below). Ketamine was used as an anesthetic on U.S. soldiers during the Vietnam War; but its use was abandoned and never spread to civilian use because the soldiers complained about sensations of floating above their body and seeing bright lights. Further experiments by numerous researchers verified that intravenous injections of ketamine could reproduce all of the commonly cited features of an NDE; including a sense that the experience is "real" and that one is actually dead, separation from the body, visions of loved ones, and transcendent mystical experiences.

Ketamine acts by blocking the receptor for the neurotransmitter glutamate. Glutamate is released in abundance when brain cells die, and if it weren't blocked, the glutamate overload would cause other brain cells to die as well. In the presence of excess glutamate, the brain releases its own glutamate receptor blocker to defend itself; and it is these blockers Dr. Jansen (amongst others) hypothesize as the cause of many NDEs.

Critics of this hypothesis point out that although some aspects of the experience may be similar, not all NDEs exactly fit the ketamine experience; and that while it might be possible to chemically simulate the experience, this does not refute the possibility that true NDEs have a spiritual component. As even Dr. Jansen notes:

Claims that NDE's must have a single explanation (e.g. Ring, 1980), or that a scientific theory must explain all of the experiences ever given the name of NDE (e.g. Gabbard and Twemlow, 1989) are difficult to justify.

Swiss scientists published in 2002 in Nature (Blanke, O., Ortigue, S., Landis, T., Seeck, M. Stimulating own-body perceptions. Nature, 419, 269 - 270, (2002).) found that electrical stimulation on a specific brain region repeatedly caused out-of-body experiences to the patient.

Research

Dr. Raymond Moody is recognized as the father of NDE research. He has chronicled and studied many of these experiences in his books: Other researchers in the field are

Further reading

External links