MDMA enhances emotional empathy and prosocial behavior

Abstract

3,4-Methylenedioxymethamphetamine (MDMA, 'ecstasy') releases serotonin and norepinephrine. MDMA is reported to produce empathogenic and prosocial feelings. It is unknown whether MDMA in fact alters empathic concern and prosocial behavior. We investigated the acute effects of MDMA using the Multifaceted Empathy Test (MET), dynamic Face Emotion Recognition Task (FERT) and Social Value Orientation (SVO) test. We also assessed effects of MDMA on plasma levels of hormones involved in social behavior using a placebo-controlled, double-blind, random-order, cross-over design in 32 healthy volunteers (16 women). MDMA enhanced explicit and implicit emotional empathy in the MET and increased prosocial behavior in the SVO test in men. MDMA did not alter cognitive empathy in the MET but impaired the identification of negative emotions, including fearful, angry and sad faces, in the FERT, particularly in women. MDMA increased plasma levels of cortisol and prolactin, which are markers of serotonergic and noradrenergic activity, and of oxytocin, which has been associated with prosocial behavior. In summary, MDMA sex-specifically altered the recognition of emotions, emotional empathy and prosociality. These effects likely enhance sociability when MDMA is used recreationally and may be useful when MDMA is administered in conjunction with psychotherapy in patients with social dysfunction or post-traumatic stress disorder.

Keywords: MDMA; ecstasy; emotion recognition; empathy; social behavior; social cognition.

Fig. 1

Subjective effects of MDMA measured using VASs. The data are expressed as mean ± s.e.m. score changes from predrug baseline in 32 subjects. ***P < 0.001, significant differences (E_max) from placebo in women/men.

Fig. 2

Effect of MDMA on (A) explicit and (B) implicit emotional empathy and (C) cognitive empathy in the MET. MDMA significantly increased emotional empathy in all subjects due to increases in men but not in women. The data are expressed as mean ± s.e.m. in 32 subjects. *P < 0.05, significant difference from placebo.

Fig. 3

Effect of MDMA on prosociality and inequality-aversion in the SVO test. (A) MDMA had prosocial effects in men, resulting in levels of prosociality equal to those of placebo-treated women. (B) MDMA tended to reduce the inequality-aversion index (P = 0.079), consistent with an increased preference for fairness. The data are expressed as mean ± s.e.m. *P < 0.05, significant difference from placebo.

Fig. 4

(A–D) Endocrine effects of MDMA and (E) plasma concentration-time curve of MDMA. MDMA increased the plasma concentrations of (A) oxytocin, (C) cortisol and (D) prolactin but not (B) copeptin. The data are expressed as mean ± s.e.m. of differences from baseline in 32 subjects. *P < 0.05, **P < 0.01, ***P < 0.001, significant difference (change in C_max) from placebo.