MDMA helps people cooperate and rebuild trust, study shows

Brain scans reveal increased activity in regions responsible for social behaviour, but drug doesn't undermine rational decision making

MDMA, the active ingredient of ecstasy pills, makes people more inclined to cooperate on tasks and quicker to rebuild trust, according to researchers investigating its use in treating psychological disorders.

Scans reveal it increases activity in parts of the brain linked to empathy and social behaviour that helps interpret other people’s beliefs and intentions, researchers from King’s College London said.

This could make it a useful addition to psychotherapy sessions and the drug is currently undergoing medical trials to assess its use in supporting treatment of post-traumatic stress disorder (PTSD).

“Understanding the brain activity underlying social behaviour could help identify what goes wrong in psychiatric conditions,” said Professor Mitul Mehta from the King’s Institute of Psychiatry, Psychology & Neuroscience (IoPPN).

“Given the social nature of psychotherapy, understanding how MDMA affects social interaction sheds light on why the drug could become a valuable tool in treating patients.”

While it is possible that making users more helpful and collaborative could lead to them being exploited, Professor Mehta and his team found the drug did not make users gullible.

After taking part in a series of challenges where the participants were able to cooperate or cheat each other, subjects on MDMA were just as likely to rate down untrustworthy as participants given a placebo.

“Importantly, MDMA did not cause participants to cooperate with untrustworthy players any more than normal. In other words, MDMA did not make participants naively trusting of others,” Professor Mehta added.

To understand how MDMA affects our brains and behaviour the team recruited 20 healthy adult men, and gave them either MDMA or a placebo while they completed a series of tasks in an MRI scanner.

One of the tasks was a version of the economics puzzle, the prisoner’s dilemma.

The task assumes two accomplices have been arrested and are being interviewed separately by the police. Each is offered a chance to turn on their partner and be released for giving evidence on a more serious crime, or stay silent and both serving a short sentence. If both partners turn on each other, then they both get a longer sentence.

During the study, published in the Journal of Neuroscience on Monday, participants on MDMA were less likely to cheat their partners than those on the placebo. Where they had previously been cheated – and knew their partner was untrustworthy – subjects on MDMA were as likely to act selfishly as those on a placebo, however they were quicker to trust these partners again after a run of cooperation.

This was backed up with patterns of brain activity, which showed MDMA lit up the superior temporal cortex and mid-cingulate cortex, regions which are known to be key in understanding and interpreting other people’s intentions and beliefs.

Meanwhile the right anterior insula, a key decision-making region of the brain engaged in appraising risk and uncertainty, showed increased activity on MDMA – but this decreased when working with less trustworthy partners.

“Using MRI scans, we were also able to see that MDMA had an impact on brain activity when processing the behaviour of others, rather than altering the decision-making process itself,” said Dr Anthony Gabay, the first author of the study.