Scientists have found that the drug ecstasy can cause people to be more trusting of others, reports New Scientist.

Why it matters: A key challenge in treating post-traumatic stress disorder with psychotherapy is fostering trust between patients and their therapists. The Medical University of South Carolina's Michael Mithoefer, who is investigating whether ecstasy can be used to relieve PTSD, cautioned there are still open questions about how the drug works but told New Scientist, "it may help people trust their therapist more and prevent them from being overwhelmed by their traumatic memories during therapy."

Researchers at King's College London gave 20 men ecstasy and scanned their brains while they played a classic social science game called the Prisoner's Dilemma. (According to the game, it is never wise to cooperate with your opponent yet people do.) Players cooperated twice as often after they took ecstasy compared to when they were given a placebo but only if their opponent (a computer) also cooperated, building the person's trust that they weren't going to be betrayed. If the computer did betray them, the players were less cooperative -- ecstasy or not.

The concern: The use of ecstasy is being limited to the first few sessions of therapy in trials but some psychologists worry even that could lead to unintended abuse. "It sends the message that this drug will help you solve your problems, when often it just creates problems," psychologist Andrew Parrott told the New York Times last fall. "This is a messy drug we know can do damage."