This story is part of When the Drugs Hit, a Motherboard journey into the science, politics, and culture of today's psychedelic renaissance. Follow along here.
The first time I experienced DMT, I was in the jungle, a few days' boat trip up the Amazon from Iquitos, Peru. When my guide learned there was a shaman living nearby the village we were staying in for the night, we made a spontaneous detour and the next thing I knew I was sipping a foul-tasting brew from a turtle shell. As night fell and the shaman began shaking his chakapa—a rattle made of dried leaves—and softly reciting healing songs called icaros, I began to feel the effects of the ayahuasca, a hallucinogenic medicine made from plants indigenous to the Amazon.
The first thing I noticed was that my vision became obscured by fractals resembling kené patterns. Shortly thereafter, I felt myself leaving my body to ascend to a timeless, endless expanse. When I arrived, I understood my journey was the process of dying and this hallucinatory purgatory was the afterlife. Contrary to what one might expect, I was overcome with a profound sense of peace from this encounter with death.
Near-death experiences (NDEs) are a notoriously tricky phenomenon to define in any rigorous clinical sense because of their subjective nature. Nevertheless, NDEs tend to share many common elements, such as feelings of inner peace, the experience of traveling through a tunnel, out of body experiences, and encounters with sentient beings. As I discovered firsthand, these sensations are also commonly experienced while under the influence of dimethyltryptamine (DMT), the main psychoactive compound in ayahuasca.
To better understand the link between this psychedelic and NDEs, researchers at Imperial College London dosed thirteen volunteers with DMT in a placebo-controlled study. Unlike ayahuasca, which has multiple psychoactive compounds and lasts for hours, straight DMT has a fast onset and lasts for only a few minutes.
The researchers’ goal was to “directly measure the extent to which intravenous DMT given to healthy volunteers in a laboratory setting could induce near-death type experience as determined by a standard NDE rating scale.” The results from the first of its kind study were published this week in the journal Frontiers in Psychology. As the researchers discovered, DMT does in fact seem to induce experiences that are qualitatively similar to near-death experiences, but the intensity of these NDEs largely depend on context.
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The sample size for the study was relatively small: The volunteers consisted of six women and seven men, whose average age was 34, all of whom had at least some experience with psychedelic drugs, such as LSD, mushrooms, or DMT. Each volunteer visited the laboratory twice—one time they were dosed with DMT and the other time they were dosed with a placebo, but they weren’t informed which was which in advance.
The dosage of DMT administered intravenously to the participants ranged from seven milligrams to 20 milligrams. During the study the participants reclined in a dimly lit room and listened to calming music while an electroencephalogram monitored their brain activity. According to the researchers, participants felt the effects of DMT within about 30 seconds of the injection, felt peak effects about two to three minutes after the injection, and only had mild residual effects 20 minutes after the injection.
To measure the participants' experience of being near death, the researchers used a scale developed in the early 80s by the psychiatrist Bruce Greyson, which was given to the participants once the effects of the DMT had worn off. Participants were also asked to gauge their subjective experiences using the Ego Dissolution Inventory and Mystical Experiences Questionnaire, two psychological surveys developed within the past few years to quantify the subjective effects of psychedelic substances.
The responses from the participants were compared to the responses from another group of participants surveyed by the researchers who had experienced “actual” near death experiences. The results indicated that “all 13 participants scored above the standard threshold for NDE in relation to their DMT experiences,” the researchers wrote in their report. In other words, “these results reveal a striking similarity between the phenomenology of NDEs and experiences induced by the classic serotonergic psychedelic, DMT.”
Furthermore, the researchers found that those who were inclined toward “delusional thinking” in their normal day-to-day life also experienced stronger near-death experiences on DMT. Their baseline proclivity toward delusion was measured by the Peters Delusion Inventory, which asks respondents to assess their belief in telepathy, witchcraft, voodoo and other similar paranormal phenomena. The reason for this correlation, the authors argue, may be that people inclined toward delusional thinking are “more emphatic in their endorsement of NDE phenomena as they view it as less at odds with their pre-existing belief systems” or even as “evidence” of the validity of those beliefs.
Rick Strassman, a psychiatrist at the University of New Mexico who was not involved in this study, was the first chemist in the United States to legally experiment with DMT in the early 90s after a decade-long moratorium. In the course of his research, Strassman dosed over 50 volunteers with DMT, but he told me in an email that a “classic NDE was rare.”
"My sense is that as consciousness ‘leaves’ the body, DMT may be mediating that process, and reflect what people are actually experiencing as they die."
According to Strassman, one of his volunteers had “what might be considered a classical NDE,” but that this volunteer came to the study with an strong interest in near-death experiences and was hoping to experience one with DMT. Another of Strassman’s subjects, who he described as a “Mexican-Native urban shaman” also experienced something similar to a near-death experience on DMT, but Strassman told me it was “more along the lines of a shamanic ‘dismemberment, death, reconstituting, rebirth’ motif.”
“If we had administered rating scales that measured ‘NDEs’ after giving DMT, we might have seen more of an overlap,” Strassman told me. “In my work, we determined ‘similarities’ to actual NDEs based on volunteers’ and my gestalt appraisals rather than via rating scales."
So while DMT does appear to be able to induce qualitatively similar sensations to near death experiences, the authors noted that the intensity of these experiences is largely dependent on context and the psychological disposition of the individual, something also noticed by Strassman. In order to get a better understanding of the overlap between DMT experiences and NDEs, however, the authors argue that a better “neurobiology of dying” is needed.
Strassman suggested that the overlap between DMT and NDEs could possibly be explained on a biological level since DMT is naturally produced in small quantities by the human body and has been shown to minimize neuronal damage due to hypoxia (insufficient oxygen) in test tubes. Thus, Strassman said “one could construct a coherent scenario where endogenous DMT rises in response to cardiac arrest/hypoxia in order to protect the brain as long as possible.”
“Why a substance with psychedelic properties is recruited, rather than say an endogenous opioid or endorphin which would simply induce oblivion is a very interesting question,” Strassman said. “My sense is that as consciousness ‘leaves’ the body, DMT may be mediating that process, and reflect what people are actually experiencing as they die. What happens after that, of course, is anyone’s guess.”