Methylenedioxymethamphetamine — the drug commonly known as ecstasy or molly — increases emotional empathy and reduces the recognition of sad faces while having no effect on moral judgments, according to new research.

In the study, published in the Journal of Psychopharmacology, researcher Yasmin Schmid and her colleagues observed that “the positive bias in emotion recognition and increase in emotional empathy induced by even a low dose of MDMA likely contribute to its popularity as a recreational drug.”

The double-blind, placebo-controlled study of 30 healthy individuals utilized the Facial Emotion Recognition Task, Multifaceted Empathy Test, Movie for the Assessment of Social Cognition, Social Value Orientation Test, and Moral Judgment Task to examine the effects of MDMA on several aspects of social cognition.

The study found that the individuals who consumed a low dose of MDMA were able to accurately infer the mental states of others in various circumstances, but tended to misclassify faces with negative expressions. MDMA had no effect on the judgment of moral dilemmas, but the drug did increase ratings in happiness, openness, trust and closeness to others.

“The main findings of the present study were that a low dose of MDMA enhanced emotional empathy for positive emotional stimuli on the MET and tended to reduce the recognition of sad faces on the FERT. The positive bias in emotion recognition and increase in emotional empathy induced by a low dose of MDMA were accompanied by only moderate subjective effects. MDMA had no acute effects on cognitive empathy on the MET or mental perspective-taking on the MASC, indicating that MDMA did not acutely alter complex social cognitive inferences,” the researchers wrote.

MDMA is often described as an “empathogen” because of its ability to amplify pro-social behaviors and feelings. The bias against recognizing negative facial expressions likely plays a role.

“A similar alteration in affect recognition, in which faces were more often mistakenly judged as neutral, particularly in response to sad facial expressions, was also found after moderate alcohol consumption. Drugs that facilitate social approach behaviour may do so by partially decreasing the correct identification of threat-related or negative facial emotion signals,” Schmid and her colleagues said.