Researchers from Imperial College London have found evidence that suggests that psilocybin, the psychoactive compound of magic mushrooms, might be useful in treating depression.

The study, published in Scientific Reports, focused on 19 patients, all of which experienced treatment-resistant depression. Each patient showed less depressive symptoms at the one week post-treatment mark. While the findings are exciting, this is a very preliminary study on a small number of people and with no control sample. More importantly, this study doesn’t mean magic mushrooms cure depression.

“We have shown for the first time clear changes in brain activity in depressed people treated with psilocybin after failing to respond to conventional treatments,” lead author Dr Robin Carhart-Harris, head of psychedelic research at Imperial, said in a statement.

Patients in the study were given two doses of psilocybin. The first dose of 10 mg was given immediately and the second dose of 25 mg was given a week after the first. The patients reported how they felt by completing clinical questionnaires.

“Several of our patients described feeling ‘reset’ after the treatment and often used computer analogies," Dr Carhart-Harris reported. "For example, one said he felt like his brain had been ‘defragged’ like a computer hard drive, and another said he felt ‘rebooted'.

"Psilocybin may be giving these individuals the temporary ‘kick start’ they need to break out of their depressive states and these imaging results do tentatively support a ‘reset’ analogy. Similar brain effects to these have been seen with electroconvulsive therapy.”

The team performed functional magnetic resonance imaging (fMRI) on 16 of the 19 patients both before and after treatment. The scans indicate a reduction in cerebral blood flow towards the temporal cortex, in particular, the amygdala. This decrease in blood flow to the amygdala was related to a decrease in depressive symptoms. The MRI also showed increased stability in another brain network linked with depression.

“Through collecting these imaging data we have been able to provide a window into the after effects of psilocybin treatment in the brains of patients with chronic depression,” Dr Carhart-Harris added.

"Based on what we know from various brain imaging studies with psychedelics, as well as taking heed of what people say about their experiences, it may be that psychedelics do indeed ‘reset’ the brain networks associated with depression, effectively enabling them to be lifted from the depressed state."

Due to these encouraging results, the team plans to conduct a comparative trial to test the effect of psilocybin against a leading antidepressant. This is set to start next year.