How a magic mushroom compound rewires the brain to relieve depression

Psilocybin, the hallucinogenic substance found in "magic mushrooms," has the ability to link regions of the brain that are more separated in people with depression and make them less stuck in negative thinking patterns.

This is especially crucial for those suffering from treatment-resistant depression; yet, while this effect has been widely documented, we don't know exactly how psychedelics flip the switch on rigid brain networks.

A new brain mapping study from a group of neuroscientists has now added to our knowledge of how psilocybin operates in the brain.

The study discovered that after two doses of psilocybin, certain regions of depressed people's brains became more interconnected and flexible, and that these changes lasted up to three weeks following treatment.

Psilocybin managed to do this in a way that other antidepressants do not, suggesting it could be used to treat depression in a unique way.

Magic mushrooms at work to relieve severe depression

Previous studies on psychedelic compounds such as LSD and psilocybin have shown substantial promise in the treatment of a variety of mental health conditions. In many cases, clinical study participants have experienced improvements in overcoming the demons of post-traumatic stress disorder (PTSD) or finding clarity in the face of a terminal illness.

However, as these studies did not reveal exactly how psychedelics rewire the mind, a group of neuroscientists decided to use neuroimaging technology to delve deep into the brain and find some answers.

The researchers enrolled people suffering from severe depression and administered either psilocybin or a standard antidepressant. The participants had no idea which one they would receive. 

Functional magnetic resonance imaging, which captures metabolic function, was used to capture two snapshots of their brain activity: the day before receiving the first dose and then three weeks after the final one. The participants also received talking therapies with registered mental health professionals.

According to the study published Monday in the journal Nature Medicine, the participants who had been given the antidepressant reported mild improvement in their symptoms over the course of three weeks, and their neural activity was constrained within certain parts of the brain. However, those who had been given psilocybin reported a quick and sustained improvement in their depression, with its heightened connectivity "resembling the cognitive agility of a healthy brain".

How psychedelics rewire the mind

"These findings are important because for the first time we find that psilocybin works differently from conventional antidepressants, making the brain more flexible and fluid, and less entrenched in the negative thinking patterns associated with depression," David Nutt, the head of the Imperial Centre for Psychedelic Research, said in a The New York Times report. "This supports our initial predictions and confirms psilocybin could be a real alternative approach to depression treatments.”

The results are exciting; however, the study does have its shortcomings such as its small size and short time frame. Furthermore, researchers who were not involved in the study have stated that the findings were not wholly shocking, but did provide a possible biologic explanation for anecdotal reports of therapeutic successes of psychedelic substances. Obviously, no one should attempt to use psychedelics without first consulting with a doctor or a therapist.

Nonetheless, the researchers are hopeful that their findings will pave the way for additional research into psilocybin's ability to treat other mental illnesses, like those characterized by rigid thought patterns.