What happens inside the human brain as life comes to an end? For decades, this question has fascinated neuroscientists, doctors and researchers studying near-death experiences. One molecule has attracted particular attention: N,N-dimethyltryptamine, better known as DMT.
DMT is a powerful psychedelic compound that occurs naturally in some plants and has also been detected in mammalian tissues. Because it can produce vivid imagery, altered perceptions of time and a powerful sense of encountering another reality, researchers have investigated whether it might help explain some extraordinary experiences reported by people who have come close to death.
The idea is intriguing: could the dying brain release DMT, producing visions, a feeling of leaving the body or the impression of travelling somewhere beyond ordinary reality?
But there is an important distinction between a compelling hypothesis and an established scientific finding.
Scientists have not demonstrated that the human brain releases a large surge of DMT during death, nor have they established that DMT causes near-death experiences. Research has produced interesting clues, particularly from animal studies, but major questions remain unanswered.
Understanding what is known—and what is still speculation—reveals why this small molecule has become such a significant topic in the science of consciousness.
1. What is DMT, and why does it interest scientists?
DMT is a naturally occurring compound belonging to a group of substances known as psychedelics. It affects serotonin receptors in the brain, particularly the 5-HT2A receptor, which is involved in perception, cognition and aspects of conscious experience.
When administered as a psychedelic, DMT can produce intense visual experiences, altered perceptions of time, powerful emotional responses and a feeling that ordinary reality has changed dramatically.
Some people report encountering seemingly intelligent beings or experiencing a sense of leaving their bodies. These descriptions have drawn comparisons with accounts of near-death experiences, in which people sometimes describe tunnels, bright lights, encounters with deceased relatives or a profound sense of peace.
However, a similarity between two experiences does not prove that they share the same biological cause.
A 2018 study published in Frontiers in Psychology compared the effects of DMT with reported near-death experiences. Researchers found meaningful similarities, supporting the idea that studying psychedelic experiences may help scientists investigate some features of near-death experiences.
The study did not establish that the human brain naturally releases enough DMT during death to produce those experiences.
2. The experiment that put DMT and death in the same conversation
Researchers investigated whether the mammalian brain could produce DMT and whether its concentration changed during cardiac arrest. Their experiments involved rats, not people.
The team detected DMT in the rats’ brains and observed a significant increase in DMT levels after experimentally induced cardiac arrest. Importantly, the increase also occurred in rats whose pineal glands had been removed.
The pineal gland is often central to popular explanations of DMT because of its role in producing melatonin, the hormone associated with regulating sleep and circadian rhythms. The experiment suggested that the pineal gland was not necessary for the observed rise in brain DMT.
The researchers published their findings in Biosynthesis and Extracellular Concentrations of N,N-dimethyltryptamine (DMT) in Mammalian Brain.
The results attracted attention because they offered experimental evidence that DMT levels can change during a life-threatening physiological event.
But there is a crucial limitation: a result observed in rats cannot automatically be assumed to occur in the same way in humans.
The study also did not establish that the measured DMT increase caused the animals to experience anything resembling a human near-death experience.
It opened a research question rather than solving the mystery.
3. Does the brain release DMT to ease the process of dying?
This is where the evidence becomes much less certain.
Some researchers have proposed that naturally occurring DMT could play a role in the brain’s response to extreme physiological stress. Others have suggested that it might contribute to altered perceptions or unusual experiences reported by people who survive cardiac arrest.
However, scientists have not established that DMT is released as a deliberate protective mechanism or that it serves a specific purpose during dying.
There are several possible explanations for changes in brain chemistry during cardiac arrest. As circulation fails, oxygen delivery declines, energy production becomes impaired and neurotransmitter systems can change rapidly.
The brain is not simply switching off like a light. The transition involves complex physiological processes whose timing and effects depend on the circumstances.
A 2025 review in Nature Reviews Neurology examined several potential mechanisms underlying near-death experiences, including changes in brain activity, neurotransmission, memory and psychological processes.
The authors proposed an integrated neuroscientific model rather than attributing these experiences to one chemical alone.
DMT remains a possible research avenue, but it is not an established explanation for what happens to consciousness near death.
4. What causes near-death experiences if DMT is not the whole answer?
Near-death experiences are varied, and researchers do not yet have a complete explanation for all their reported features.
Several mechanisms may contribute.
Oxygen deprivation and changes in blood flow: When the brain receives insufficient oxygen, its normal activity can become disrupted. Such changes may affect perception, awareness and memory.
Altered brain-network activity: The networks responsible for integrating sensory information, memory and a person’s sense of self can change under extreme physiological stress.
Neurotransmitter changes: Multiple chemical signalling systems may be affected around cardiac arrest and resuscitation. DMT is only one candidate among several proposed mechanisms.
Memory and perception: The experience reported afterward may be influenced by how memories are formed, reconstructed and interpreted during recovery.
A 2019 analysis comparing approximately 15,000 written reports involving 165 psychoactive substances with 625 near-death experience narratives found that ketamine-related reports were especially similar to near-death narratives in its analysis. DMT also showed similarities.
The study, published in the journal Consciousness and Cognition, is available through PubMed.
This finding is important because it suggests that DMT is not the only substance capable of producing experiences with near-death-like features. It also demonstrates why similarities in subjective experience cannot, by themselves, identify the underlying chemical mechanism.
5. Could DMT explain seeing a tunnel or meeting deceased relatives?
It is possible that changes in brain function contribute to some features of near-death experiences, but there is no definitive evidence that endogenous DMT explains the full range of reported phenomena.
DMT can produce vivid imagery and unusual perceptions in people who take it. Some accounts resemble reports from people who have survived life-threatening events.
Yet the experiences are not identical. A 2025 comparative study in Frontiers in Psychology found both similarities and differences between naturalistic DMT experiences and near-death experiences.
There is also an important measurement problem. Researchers generally cannot directly observe and interview someone during the entire period in which a fatal physiological crisis unfolds. Survivors describe their experiences afterward, and investigators must determine when the experiences occurred and how they relate to brain activity.
Consequently, the timing and biological origins of individual experiences can be difficult to establish.
Reports of encounters with deceased relatives or a sense of travelling beyond the body are meaningful to the people who experience them. Neuroscience can investigate possible mechanisms without assuming that every detail has already been explained.
Equally, such reports do not independently establish that consciousness leaves the brain or continues after irreversible brain failure.
6. The biggest unanswered question: how much DMT is actually present?
Detecting a substance in the brain is not the same as demonstrating that it reaches a concentration capable of producing a particular psychological effect.
Researchers must establish where a compound is produced, how it moves through the body, how quickly it is broken down and whether its concentration is sufficient to affect the relevant receptors.
A 2025 review of endogenous DMT research examined its possible biological roles and the remaining uncertainties surrounding its synthesis and regulation.
Scientists still lack direct evidence establishing a death-related DMT surge in the human brain comparable to the one observed in the rat experiment.
It would also be difficult to measure these changes directly in dying humans under controlled experimental conditions. Any future research would need to address substantial ethical and technical challenges.
Until those gaps are addressed, claims that a massive DMT release floods the human brain at death remain unproven.
Conclusion: The DMT mystery is far from solved
The possibility that DMT contributes to near-death experiences is scientifically interesting, but the popular claim that the brain releases a powerful psychedelic flood as death approaches goes beyond the available evidence.
Animal experiments have demonstrated that brain DMT levels can rise following cardiac arrest. Human studies have found similarities between some psychedelic experiences and near-death accounts. Reviews of the field suggest that several interacting neurological and psychological processes may help explain these experiences.
What researchers have not established is whether the human brain produces a comparable DMT surge during dying, whether such a surge causes near-death experiences or whether the molecule serves a specific biological purpose at that time.
The next stage of research will need better evidence about endogenous DMT concentrations, their effects on human brain function and their relationship to the timing of near-death experiences.
For now, DMT is a promising subject of investigation—not a confirmed chemical explanation for what happens when we die.
