Researchers looked into the brain to show how taking DMT affects human consciousness, significantly changing the electrical activity of the brain.
DMT (or dimethyltryptamine) is one of the main psychoactive ingredients in Ayahuasca, a psychedelic drink traditionally made from the vine and leaves of the Amazon rainforest. The drink is usually prepared as part of a shamanic ceremony and is associated with unusual and vivid visions or hallucinations.
The latest study is the first to show how a powerful psychedelic changes our waking brainwaves – and scientists compare its powerful effects with "sleep while sleeping".
The work of scientists at the Center for Psychedelic Research at Imperial College London and published today in the Scientific Reports journal can help explain why people taking DMT and ayahuasca experience intense images and immersive "daydream" sensations.
DMT is a naturally occurring chemical found in small amounts in the human brain, but also in larger amounts in many plant species around the world.
The accounts of people who took DMT describe intense visual hallucinations, often accompanied by strong emotional experiences and even a "breakthrough" in what users define as an alternate reality or dimension.
It is obvious that people are completely immersed in their experiences – it's like a dream only much more vivid and engaging, it's like a dream, but with open eyes Christopher Timmermann Center for Psychedelic Research
But scientists are interested in using a strong psychoactive compound for research because it produces relatively short but intense psychedelic experiences, providing a window to collect data on brain activity when consciousness is deeply changed.
In a recent study, the Imperial team captured EEG measurements from healthy subjects in a clinical setting in a placebo-controlled system.
A total of 13 participants received an intravenous DMT infusion at the Imperial Institute for Clinical Research National Institute for Health Research (NIHR). Volunteers were equipped with caps with electrodes to measure brain electrical activity, before, during and after the infusion, with the peak of the psychedelic experience lasting about 10 minutes.
The analysis showed that DMT significantly changed the electrical activity in the brain, characterized by a clear decrease in alpha waves – the dominant electric rhythm of the human brain when we are awake. They also discovered a short-term increase in brain waves usually associated with sleep, namely theta waves.
"Chaotic" brain activity
In addition to changing brain wave types, they also found that overall brain activity has become more chaotic and less predictable – unlike in states of reduced consciousness, such as deep sleep or general anesthesia.
"The changes in brain activity that accompany DMT are slightly different from what we see in other psychedelics, such as psilocybin or LSD, in which we see mainly only brain wave reductions," said lead author Christopher Timmermann of the Psychedelic Research Center.
"We saw a rhythm appearing here that was present during the most intense part of the experiment, suggesting the emergence of order among the chaotic patterns of brain activity.
"Changed brainwaves and participant reports suggest that these people are completely immersed in their experiences – it's like a dream only much more vivid and engaging, it's like a dream, but with open eyes."
Research with DMT can provide important insights into the relationship between brain activity and consciousness, and this small study is the first step on this path Dr. Robin Carhart-Harris Center for Psychedelic Research
Timmermann explains that while it is unclear whether DMT may have clinical potential at this stage, the group hopes to continue working by providing a continuous DMT infusion to expand the window of psychedelic experience and collect more data.
The team says that future research may include more advanced brain activity measurements, such as fMRI, to show which regions and brain networks are affected by DMT. They believe that the visual cortex, a large area towards the back of the brain, will probably be involved.
Dr Robin Carhart-Harris, head of the Psychedelic Research Center, said: "DMT is a particularly intriguing psychedelic. The visual vividness and depth of immersion produced by high doses of the substance seem to exceed the scale described for the more widely studied psychedelics, such as psilocybin or "magic mushrooms".
"It's difficult to capture and communicate how it is for people experiencing DMT, but it is useful to compare it to sleep in a waking state or near death.
"In our view, research with DMT can provide important information about the relationship between brain activity and consciousness, and this small study is the first step on this path."
"Neural correlations of DMT experience evaluated with EEG on many varieties" Christopher Timmermann et al. is published in the journal Scientific reports. DOI: 10.1038 / s41598-019-51974-4
Function image: From rendered EEG video output showing alpha wave fall. Source: Masahiro Kahata