One Dose of Psilocybin May Briefly Alter the Brain, Offering Clues for New Treatments
Just one dose of the psychedelic compound psilocybin could cause some anatomical brain change lasting up to a month, according to new research in Nature Communications.
Researchers from Imperial College London and the University of California, San Francisco (UCSF) found a link between temporary shifts in brain “entropy” (diversity of neural activity) and insight (emotional self-awareness). This link could explain how psilocybin impacts conditions like anxiety, depression, and addiction, and that the psychedelic experience itself is a crucial component of its therapeutic effects.
“Psychedelic means ‘psyche-revealing,’ or making the psyche visible,” said senior author Robin Carhart-Harris, Ph.D., the Ralph Metzner distinguished professor of Neurology at UCSF, in a press release. “Our data shows that such experiences of psychological insight relate to an entropic quality of brain activity and how both are involved in causing subsequent improvements in mental health. It suggests that the trip — and its correlates in the brain — is a key component of how psychedelic therapy works.”
Testing Healthy Brains with Psilocybin
For the study, the research team administered psilocybin to 28 adult volunteers with no history of mental health conditions and who had never taken a psychedelic before.
During the first part of the experiment, the research team gave the volunteers a 1-milligram (mg) dose of psilocybin — which the team considered a placebo — and monitored their brain activity using electroencephalography (EEG). This technique records electrical activity from electrodes placed on the subjects’ scalps.
From there, over a series of a few weeks, the team continued to monitor the volunteers’ cognitive abilities, well-being, and psychological insight using functional MRI (fMRI) and diffusion tensor imaging (DTI).
After one month, the team then administered a 25-mg dose of psilocybin to the volunteers to elicit a strong psychedelic trip. During the following weeks, the team monitored the volunteers using the same methods as they did with the 1-mg dose and compared the effects of the placebo and the larger dose. The results were rather shocking.
Read More: Magic Mushroom Compound Psilocybin May Have Anti-Aging Properties
What the Results Reveal
While monitoring the subject’s brains, researchers noted that within the first hour of taking the 25-mg dose, the volunteers had high entropy, indicating that the brain was likely processing richer information under the psychedelic.
After a month, the DTI — which measures water diffusion along neural tracts — showed changes in how water moved along certain white‑matter pathways, suggesting subtle shifts in brain microstructure. Researchers say such results are unusual in human studies, and while they are fascinating, more study is still needed to understand these changes in the brain.
Psilocybin Appears to Improve Mental Health and Cognition
After taking the 25-mg dose, the volunteers were given a survey and asked to rate the trip. Twenty-seven out of the 28 participants ranked their trip as the “single most unusual state of consciousness they had ever experienced,” according to the press release. The single participant ranked this experience as among the top five.
From the survey, the research team also noted that the volunteers had all experienced greater psychological insight after taking the 25-mg dose than the 1-mg dose, and an overall increase in well-being for 2 to 4 weeks after the study.
“I’ve been feeling optimistic about the future,” and “I’ve been dealing with problems well,” one of the volunteers reported in the survey.
The research team noted that after about a month, the subjects all performed better on a cognitive flexibility test.
“Psilocybin seems to loosen up stereotyped patterns of brain activity and give people the ability to revise entrenched patterns of thought,” said Taylor Lyons, Ph.D., a research associate at Imperial College London and the first author of the paper, in a press release. “The fact that these changes track with insight and improved well‑being is especially exciting.”
Lastly, the results also show that the volunteers with the largest increase in brain entropy immediately after taking psilocybin also seemed to have increased insight the following day and improved well-being after a month, suggesting that improved well-being was linked to insight.
With these findings, the research team hopes to improve mental health treatments with psilocybin.
“We already knew psilocybin could be helpful for treating mental illness,” Carhart-Harris said in the press release. “But now we have a much better understanding of how.”
This article is not offering medical advice and should be used for informational purposes only.
Read More: Psychedelics Like LSD, Psilocybin, and DMT May Rewire the Brain in the Same Two Ways — With Implications for Mental Health
Article Sources
Our writers at Discovermagazine.com use peer-reviewed studies and high-quality sources for our articles, and our editors review for scientific accuracy and editorial standards. Review the sources used below for this article: