New Study Indicates Why DMT Can't Explain Near-Death Experiences

Ever since Raymond Moody's best-selling 1975 book Life after Life, the common characteristics of a near-death experience have been well-known. A particular near-death experience may have between one or more of these characteristics. The characteristics include:

• a sensation of floating out of the body, which may include seeming to view the body from above;
• feelings of peace, joy or tranquility;
• a life-review in which previous life events are reviewed or relived in some sped-up manner;
• a passage through a tunnel;
• an encounter with a very bright light or a “being of light” or a light that is somehow sensed to be numinous or a source of thought or feeling;
• an experience of seeing some heavenly or supernatural realm;
• an experience of seeming to see one or more deceased relatives;
• an experience of being told that you must “go back” and continue to live your regular life;
• an experience of having heightened consciousness, mentality or perception.

Since near-death experiences were first reported, those who do not believe in a soul or life after death have been trying to suggest a natural explanation for the phenomenon.  One attempt at an explanation is what we may call the "stash release" theory. This is the idea that when someone is at the verge of death or undergoing a cardiac arrest, there can be a release of hallucinogenic chemicals stored in the brain.  A person may try to back up this claim by saying something like "DMT has been detected in the brain of mammals." However, there has never existed any evidence that any hallucinogenic chemicals exist in the brain of mammals other than in micro-traces a thousand times too small to produce a hallucination.  

There's a new study on the topic published in a scientific journal. It is remarkable how the press release on this topic (and the NeuroscienceNews.com story based on the press release) misleadingly describe the study as if it were something supporting the "stash release" theory. The headline on NeuroscienceNews.com is " ‘Mystical’ psychedelic compound found in normal brains."  The story tells us that DMT has been discovered in mammalian brains. It also says, "Her team’s work has also revealed that the levels of DMT increase in some rats experiencing cardiac arrest." But no mention is made in the story of what level of DMT was found in a mammalian brain, and no mention is made by how much the DMT level increased during cardiac arrest. You should tend to be suspicious of scientific news stories that fail to provide the relevant numbers. 

Luckily the story is based on a study in a scientific journal, and the whole study can be read online here.  Deplorably, the study does not reveal in its abstract what level of DMT was measured.  But if you dive into the study we can get that information. The level of DMT detected was about 1 nanomole, a billionth of a mole. The paper states, "the normal rat brain contained detectable levels of DMT..ranging 0.05–1.8 nM with an average of 0.56 nM." The abbreviation nM stands for nanomole. So the study tells us that a rat brain has only about 1 nanomole of DMT.

How much is a nanomole?  It's about 300,000 times smaller than the amount needed to produce a hallucinogenic result. The dose typically used to produce DMT hallucinations or a DMT "trip" is about 30 milligrams.  That's a dose about 300,000 times stronger than a nanomole.  

According to the site here, which can be used as a rough guide, 5750 milligrams of a particular substance is equivalent to .05 moles. So an amount 100 times smaller (about 57 milligrams) would be equal to about .0005 moles. We multiply that .0005 by a billion to get the equivalent number of nanomoles, leaving us with 500,000.  So a dose of 57 milligrams is about 500,000 nanomoles, a dose of 30 milligrams is about 300,000 nanomoles, and a single nanomole is only about 1/300,000 of the minimum 30 milligrams to produce a hallucinogenic result. 

As for the claimed cardiac arrest increase in DMT, the paper shows that it is only an increase from 1 nanomole to 2 nanomoles. That means that even during cardiac arrest, the DMT would still be 150,000 times too small to produce a hallucinogenic result. 

The news article written about the study failed to make any mention of the fact that mere nano-traces of DMT had been measured.  This is not quite chicanery and deceit. It is also not quite chicanery and deceit for a man to vaguely tell his girlfriend, "I have accumulated some savings," when these savings consist merely of one penny deposited each month into a piggy bank. 

See the post here for why there is a huge difference between DMT experiences and near-death experiences, and why DMT could not actually explain near-death experiences, even if it existed in the brain a million times greater than the nano-traces that have been detected. 

A DMT trip is a little like this

Postscript: There's a new study indicating that near-death experiences are astonishingly common. The study is entitled “Prevalence of near-death experiences and REM sleep intrusion in 1034 adults from 35 countries.” Using a “crowdsourcing” platform to get a random sample of 1034 adults from many different countries, the study authors found that 28% of the respondents answered “Yes” when asked whether they had ever had a near-death experience.

This 28% was then asked to answer “Yes” or “No” to the following questions (called “Greyson scale questions”):

• Did time seem to speed up or slow down?

• Were your thoughts speeded up?

• Did scenes from your past come back to you?

• Did you suddenly seem to understand everything?

• Did you have a feeling of peace or pleasantness? *

• Did you have a feeling of joy?

• Did you feel a sense of harmony or unity with the universe?

• Did you see, or feel surrounded by, a brilliant light?

• Were your senses more vivid than usual?

• Did you seem to be aware of things going on elsewhere, as if by extrasensory perception or telepathy?

• Did scenes from the future come to you?

• Did you feel separated from your body?

• Did you seem to enter some other, unearthly world?

• Did you seem to encounter a mystical being or presence or hear an unidentifiable voice?

• Did you see deceased or religious spirits?

• Did you come to a border or point of no return?

Only those who answered “Yes” to 7 or more of these questions were judged to have had a “full-scale” near-death experience. Ten percent of the respondents answered “Yes” to 7 or more of these questions.

You may realize how remarkable such a result is when you consider that only a small fraction of the population have ever come close to death. There are no exact figures on what percentage of the population has come close to death, but a reasonable ballpark estimate might be between 10% and 20%. So it seems like a very high fraction of those who come to death experience near-death experiences.

The scientific paper tries to suggest some causal relation between what is called “REM sleep intrusion” and near-death experiences. REM sleep intrusion is supposedly some state in which someone can briefly dream while he is awake. To try to determine the level of “REM sleep intrusion” in respondents, the scientific survey asked these questions:

• Just before falling asleep or just after awakening, have you ever seen objects, things or people that others can’t see?
• Just before falling asleep or just after awakening, have you ever heard voices, music or sounds that other people can’t hear?
• Have you ever awakened and felt paralyzed or found that you were unable to move?
• Have you ever had abrupt muscle weakness in your legs or knee buckling, or felt sudden muscle weakness in your face or head drop?

Twenty percent of the overall respondents answered “Yes” to three or more of these four questions, but 34% of those who claimed to have a near-death experience answered “Yes” to three or more of these questions. 47% of those who were judged to have had “full-scale” near-death experiences answered “Yes” to three or more of these “REM sleep intrusion” questions.

The authors have tried to play this up as something significant, but it may have no causal significance at all. We can easily explain the difference without imagining any causal relation between “REM sleep intrusion” and near-death experiences.

The “REM sleep intrusion” questions are questions about abnormal experiences. Anyone answering the survey and reporting a near-death experience might simply be someone more prone to candidly admit to an abnormal experience.

In many ways we are socially conditioned not to report abnormal experiences, for fear of being ridiculed as an oddball. But if a person has already admitted in a survey that he has had one type of abnormal experience (a near-death experience), he may then be much more likely to admit another type of abnormal experience involving sleeping. This greater tendency to confess to a second abnormal experience (after confessing to a first abnormal experience) can easily explain the somewhat greater “REM sleep intrusion” scores of people who experienced near-death experiences.

The page here briefly explains why “REM sleep intrusion” is not a credible explanation for near-death experiences, and the paper here explains such a thing in much greater length.