London: Psychedelic drugs like magic mushrooms can help relieve the symptoms of depression, without the 'dulling' of emotions linked with antidepressants, a study has found.
Working out if someone is happy, angry or afraid, from the look on their face, is a skill we may take for granted.
For some people, however, such as those with chronic depression, this innate ability to pick up on and respond to emotional prompts like a facial expression can be disrupted, with the brain becoming oversensitive to negative stimuli.
While antidepressants drugs can help to combat the symptoms of depression for patients, they can dampen how the brain processes strong emotions - effectively turning down the dial on the hypersensitivity to negative emotions but also 'blunting' intense positive mood.
Researchers at the Imperial College London in the UK suggest that psychedelics, like magic mushrooms, may hold the key to sidestepping some of these effects in treating depression, by reviving the brain's activity and effectively reconnecting patients with their emotions.
Previous research has shown that psilocybin - the active compound in magic mushrooms - may help to alleviate symptoms in patients with persistent depression by 'resetting' brain activity.
In the study published in the journal Neuropharmacology, researchers focused on the potential of the drug to change brain activity in key areas involved in emotional processing.
They found that after treatment with psilocybin, patients with depression who did not respond to conventional treatments, reported improvements in their mood and symptoms.
However, the researchers also observed a stronger response to emotional faces with increased brain activity in an area called the amygdala - the almond-shaped region of the brain involved in processing emotions and which is known to play a role in depression.
The findings suggest an alternative pathway to tackling the changes seen in the depressed brain, which could potentially avoid some of the side effects seen with "Prozac- like' selective serotonin reuptake inhibitors (SSRIs), the most commonly prescribed antidepressants.
"Our findings are important as they reveal biological changes after psilocybin therapy and, more specifically, they suggest that increased emotional processing is crucial for the treatment to work," said Leor Roseman, from Imperial College.
In the small, trial a total of 20 volunteers with depression were recruited and asked not to take any antidepressant medication in the two weeks leading up to the trial.
They were then given two oral doses of psilocybin alongside psychiatric support, receiving an initial low dose of the drug before taking a second, much stronger therapeutic dose a week later.
In order to capture changes in brain activity, 19 of the volunteers completed fMRI scans before and after treatment.
They were shown images of human faces that were either happy, scared or neutral, with the fMRI capturing their responses as changes in blood flow throughout different regions of the brain.
Following treatment, patients reported feeling emotionally re-connected and accepting, with one patient describing the experience as an 'emotional purging'.