The findings, published in the journal Biological Psychiatry, bring more clarity to how the drug might be used clinically for the treatment of anxiety and post-traumatic stress disorder (PTSD).
While MDMA has been a popular recreational drug since the 1980s, there has been little research on which areas of the brain it affects. This is the first study to use fMRI on resting participants under the drug’s influence.
For the study, 25 volunteers were given brain scans on two separate occasions — one after taking the drug and one after taking a placebo, without knowing which they had been given.
While inside the scanner, participants were asked to recall their favorite and worst life memories. They rated their favorite memories as more vivid, emotionally intense and positive after MDMA than placebo, and they rated their worst memories less negatively.
These feelings were found to correlate to certain parts of the brain that were activated more or less strongly under MDMA.
The findings revealed that MDMA decreases activity in the limbic system –a set of brain structures involved in emotional reactions. The effects were stronger in participants who reported stronger subjective experiences, suggesting a connection.
Under the influence of MDMA, communication between the medial temporal lobe and medial prefrontal cortex (involved in emotional control) was reduced. This effect, and the drop in limbic system activity, is opposite to patterns seen in patients who suffer from anxiety.
“We found that MDMA caused reduced blood flow in regions of the brain linked to emotion and memory. These effects may be related to the feelings of euphoria that people experience on the drug,” said Dr. Robin Carhart-Harris from the Department of Medicine at Imperial College London, who performed the research.
On the other hand, communication was heightened between the amygdala and the hippocampus—the opposite of what is typically seen in patients with PTSD.
“In healthy volunteers, MDMA seems to lessen the impact of painful memories. This fits with the idea that it could help patients with PTSD revisit their traumatic experiences in psychotherapy without being overwhelmed by negative emotions, but we need to do studies in PTSD patients to see if the drug affects them in the same way,” said Carhart-Harris.
MDMA has been investigated as an adjunct to psychotherapy in the treatment of PTSD, with a recent pilot study in the U.S. reporting positive preliminary results.
“The findings suggest possible clinical uses of MDMA in treating anxiety and PTSD, but we need to be careful about drawing too many conclusions from a study in healthy volunteers. We would have to do studies in patients to see if we find the same effects,” said project leader Dr. David Nutt, a professor of neuro-psychopharmacology at Imperial College London.
Source: Imperial College London