Have you ever wondered why people who nearly die often describe speeding toward supernatural light, or seeing their life flash before their eyes? You may have also heard about the powerful psychedelic dimethyltryptamine (DMT), a class A illegal drug in the UK, and how it might generate the so-called near-death experiences. In a recent study I compared both types of experience and found they share fascinating similarities – but also critical differences.
Some studies have suggested there are some basic overlaps between the experiences people have during a near-death experience and taking DMT. But my doctoral research was the first to make an in depth and nuanced qualitative comparison between DMT trips and NDEs. It was also the first field study of its kind, capturing authentic experiences instead of asking participants to take DMT in a laboratory.
Thirty-six participants took vaporised high-dose DMT, typically inhaled from a glass pipe, in familiar settings like their own homes. My colleagues and I used an interviewing technique inspired by micro-phenomenology, a new scientific approach which aims help people discover ordinary but inaccessible dimensions of our lived experience.
This approach helps interviewees recall details of their experience by asking them to articulate it moment by moment in their own words and in chronological order, while expanding out different dimensions such as sensory or emotional experiences.
This allowed us to explore the experiences with greater granularity. For example, in what way the general themes, such as meeting unusual beings or feeling yourself dissolve entirely, specifically expressed itself.
It also allowed us to measure how often each type of these details occurred. We then compared these descriptions to our analysis of another team’s raw data from their 2018 publication studying 34 cardiac arrest-induced NDEs.
My study found both types of experiences also had important differences which researchers have previously overlooked.
People in both groups commonly reported feeling detached from their bodies, encountering beings, travelling through mysterious spaces such as tunnels or voids, and seeing bright lights. These shared experiences hint at similar brain processes at play, like disruptions in the parts of the brain that handle the map of our body, how we simulate other people’s perspectives, sensory perception and spatial processing.
However, DMT trips almost never involved the more classic NDE “life review”, or dramatisations of experiencers’ return to life as in encountering a symbolic threshold of no return. Conversely, NDEs virtually never entailed the visuals of complex geometric patterns iconic to the DMT trip.
The most compelling difference, however, was in the way these features were represented. For example, while people with NDEs frequently reported meeting dead loved ones, DMT users universally described encounters with otherworldly or alien beings.
Suddenly finding yourself transformed into a spirit witnessing your body from above, before being greeted by a guide seemed to be characteristic of NDEs. DMT would simply dissolve people’s bodily awareness, as they rapidly shot into a transcendent world inhabited by mechanical clowns or serpentine scientists.
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My colleagues and I suggest that a blend of shared brain biology and personal psychology may explain why these experiences are so similar in their generic elements but differ in their content.
Some especially intriguing phenomena in NDEs, such as the “Peak in Darien” experience where the dying see others they did not know were dead, or correctly perceive things in their surroundings when out of body, are not yet fully explained by neuroscience. B
ut the common features mentioned above probably come directly from how DMT or the near-death state affects our brains. Think of these as universal stage props, set by our brain’s biology. But the stories we attach to these props – seeing your dead aunt or a multi-eyed octopoid alien – are influenced by our personal backgrounds, cultural expectations and memories.
DMT and the brain
Early psychedelic researchers suggested that DMT might flood the brain. during near-death conditions. But life isn’t that simple – and nor is death.
Studies have shown, for example, that rats produce DMT not only via their pineal glands, but in their cortical tissue, including at the point of death. But there isn’t yet evidence that this happens in human brains. Even if humans do produce DMT at psychoactive quantities in the throes of dying, our body’s enzymes could break it down before it reaches or has enough impact on the brain. Additionally, serotonin surges dramatically when you’re under extreme stress, which may itself confer psychedelic effects – and also sticks to the serotonin receptor more happily than DMT, possibly eclipsing any DMT activity.
All this said, some scientists argue the measuring methods used to measure rat brain DMT during cardiac arrest might miss short-lived, higher DMT spikes throughout the brain. And some researchers also think damage to certain neural networks and oxygen deprivation near death might amplify DMT’s psychedelic effects.
Interestingly, our study also discovered a subset of near-death experiences that lacked the imagery of a prototypical NDE, and instead presented abstract, cosmic visions more typical of DMT trips. It’s not easy to say where these atypical NDEs could be coming from. But it could be when someone has less preconceptions of NDEs or greater preconceptions of a psychedelic trip. Perhaps their body was synthesising higher levels or DMT than is usual for an NDE. The next frontier of this research would be to track brain activity when general features crop up. We also need more research to explore potential psychological and cultural reasons why these features are expressed in the way that they are.
Many indigenous people around the globe may feel contemporary science is superfluous. Ayahuasca, a shamanic brew that contains DMT, has been used by tribes all over the Amazon to connect to the spirit world and commune with their ancestors.
People who have an NDE almost always feel their fear of death lift afterwards. Since DMT reproduces many aspects of NDEs, it could become a powerful therapeutic tool (alongside psychological support) particularly for people facing existential anxiety or fear of death, whether they are terminally ill or physically healthy. Scientists are already exploring whether ayahuasca may treat prolonged grief disorder.
We’re just starting to demystify what the implications of DMT – this “mystical” substance – may be.
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