DMT: what happens in a brain under the influence of this hallucinogenic drug?

Ayahuasca, commonly known as yagé, is a hallucinogenic brew used by shamans for at least 1,000 years for spiritual and physical healing. This drink results from a mixture of the ayahuasca vine (Banisteriopsis caapi) and the chacruna shrub (Psychotria viridis), which contains dimethyltryptamine (DMT) a psychoactive component. Today, some people (illegally) use DMT purely recreationally and report reaching deep states of altered consciousness. Some even say they have experienced feelings of imminent death. All these testimonials intrigued researchers at Imperial College London (UK) so much that they tried to understand what was happening in a brain under the influence of this “spirit molecule”. According to the results of their study published in the journal Scientific Reportsthis experience would be a form of waking dream.

So they recruited 13 volunteers (six women and seven men), with an average age of 34.4 years, and gave them controlled doses of DMT. While the participants were on drugs, the scientists recorded electrical activity in their brains using electroencephalograms (EEG).

The researchers were able to discover that participants who received injections of DMT showed a marked decrease in alpha waves. These are the brain waves usually most present when we are awake and relaxed. For a short period, however, they observed an increase in theta waves in the brains of the volunteers. These are brain waves associated with dreaming. Finally, in people on DMT, brain activity became more chaotic, resembling what happens in the brain during general anesthesia or a state of deep sleep.

“It’s as if they were dreaming but with their eyes open”

“The changes in brain activity that accompany DMT are slightly different from what you see with other psychedelics, like psilocybin or LSD, where you mostly only see reductions in brain waves,” explains Christopher Timmermann, lead author of the study.

Yet, “here we saw an emergent rhythm that was present during the most intense part of the experience, suggesting an emergent order among the otherwise chaotic patterns of brain activity. From the altered brainwaves and participants’ reports, it’s clear that these people are completely immersed in their experience – it’s like they’re dreaming but with their eyes open,” he explains.

“DMT is a particularly intriguing psychedelic. The visual vividness and depth of immersion produced by high doses of the substance appears to be on a larger scale than what is reported with more widely studied psychedelics, such as psilocybin or ‘magic mushrooms’,” comments Robin Carhart. -Harris, co-author of the study.

Sometimes traumatic experiences

“It’s hard to capture and communicate what it’s like for people on DMT, but it’s helpful to compare it to a daydream or near-death experience. We feel that DMT research could help us better understand the relationship between brain activity and consciousness, and this small study is a first step in that direction.

In the media, you can find a few testimonials of people telling about their first experience of DMT. “For a few seconds I saw the image of my family walking hand in hand, smiling – it was crystal clear. A scene of absolute bliss. I wondered how it was possible. It was so clear and at the same time, I could see through the ceiling”, recalls in particular a user interviewed by the site Vice.

If this testimony has something to fantasize about, remember that, like all drugs, DMT is not without danger. Its consumption causes nausea and vomiting. But it is above all at the psychological level that the risks are significant. Indeed, the strong changes in the perception and dissolution of one’s own identity can be experienced as traumatic by some. In the long term, consumed too regularly, this substance can also lead to permanent disorders in terms of self-perception and reality. Latent psychoses can then reveal themselves.