They're called magic mushrooms because people who eat them experience hallucinations. But a pair of new studies from Imperial College London suggests the 'shrooms may also have a magical effect on people suffering from depression.
Psilocybin, the active ingredient in magic mushrooms, is known to trigger wild sensory experiences and changes in consciousness. But one of the aforementioned studies, published in Proceedings of the National Academy of Sciences, suggests that instead of "expanding" brain activity, psilocybin actually curtails it.
Scientists gave psilocybin to 30 people and monitored their brain activity with an MRI scanner. The scans showed that psilocybin was linked to reduced activity in regions of the brain associated with high-level reasoning.
"These hubs constrain our experience of the world and keep it orderly," Dr. David Nutt, a professor of medicine at the college and senior author of both studies, said in a written statement. "Deactivating these regions leads to a state in which the world is experienced as strange."
One brain region affected by psilocybin, the medial prefrontal cortex, is typically overactive in depressed individuals. Researchers suspect the drug may help alleviate depression by curbing activity in that region. This would explain previous research that found that when patients with anxiety were given psilocybin, their depression scores fell.
Similarly, researchers found that psilocybin reduced activity in a region called the hypothalamus, which is known to be overactive during certain types of headaches. They believe this is the reason some sufferers experienced improved symptoms under psilocybin.
For the second study, slated for publication in the British Journal of Psychiatry, researchers asked 10 people to think about memories associated with strong positive emotions. Participants who had taken psilocybin reported their memories as more vivid compared with participants given a placebo.
Two weeks later, the same people were asked to rate changes in their emotional well-being. Researchers discovered a strong link between participants' ratings of how vivid their memories were, and their well-being two weeks later. They conjecture that psilocybin facilitates access to personal memories and emotions, which may boost mental health.
What's the take-away message? Psilocybin may calm overactive brain regions that contribute to headaches and depression, while enhancing emotional stability. Taken together, both pieces of research point to the chemical as a useful adjunct to psychotherapy, according to Robin Carhart Harris, a researcher who worked on both studies.
"We're not saying go out there and eat magic mushrooms," Nutt told Reuters. "But...this drug has such a fundamental impact on the brain that it's got to be meaningful - it's got to be telling us something about how the brain works. So we should be studying it and optimizing it if there's a therapeutic benefit."