These results indicate that a moderate dose of MDMA given in a social context causes considerably greater brain activation than the same dose given to solitary rats. This activation involves specific neural circuits that are known to regulate affiliative behavior, perhaps by modulating the incentive value of social stimuli. A possible role for the neuropeptide oxytocin in mediating the prosocial effects of MDMA is discussed.
To better understand these effects, we conducted a within-subjects double-blind placebo controlled study of the effects of 1.5 mg/kg oral MDMA on social emotions and autobiographical disclosure in a controlled setting. MDMA displayed both sedative- and stimulant-like effects, including increased self-report anxiety. At the same time, MDMA positively altered evaluation of the self (i.e., increasing feelings of authenticity) while decreasing concerns about negative evaluation by others (i.e., decreasing social anxiety). Consistent with these feelings, MDMA increased how comfortable participants felt describing emotional memories.
Animal research shows that heat and crowding potentiate the acute effects of MDMA. Social interaction and intravenous drug self-administration in laboratory rats are significantly enhanced when MDMA is given under hot ambient temperatures. Loud noise and physical activity can also contribute to the general overarousal. Furthermore, MDMA impairs homeostatic thermal control in rats, leading them to overheat in hot environments. The human implications of these findings are that the hot, noisy and overcrowded conditions at raves may be providing the ideal environment to heighten the acute drug response. In recreational users, the acute medical dangers of MDMA comprise a constellation of hyperthermia-related abreactions, which generally only occur when it has been taken in hot and crowded environments. MDMA is well established as a serotonergic neurotoxin in laboratory animals, but heat and overcrowding increase the degree of distal axon terminal loss. If this also occurs in humans, then the stimulatory environments of clubs and raves may heighten the likelihood of adverse neuropsychological sequelae in recreational ecstasy users. Consistent with this prediction, the extent of self-reported dancing/exercise when on MDMA has recently been shown to be associated with significantly more psychobiological problems afterwards.
MDMA slowed perception of angry expressions, increased psychophysiological responses to happy expressions, and increased positive word use and perceptions of partner empathy and regard in a social interaction.
Individually housed mice were exposed to anosmic standard opponents 30 min after drug administration, and the encounters were videotaped and evaluated using an ethologically based analysis. MDMA (8 and 15 mg kg−1) produced a behavioural pattern characterized by a marked decrease of aggression (threat and attack) as well as social investigation, body care and digging behaviours, without affecting immobility. Moreover, avoidance/flee and defence/submission behaviours were significantly increased by the drug... Overall, these findings might indicate that MDMA has anxiogenic-like properties in male mice.
MDMA decreased the effect of simulated social rejection on self-reported mood and self-esteem and decreased perceived intensity of rejection, measured as the percent of ball tosses participants reported receiving
MDMA enhanced emotional empathy for positive emotionally charged situations in the MET and tended to reduce the recognition of sad faces in the Facial Emotion Recognition Task. MDMA had no effects on cognitive empathy in the Multifaceted Empathy Test or social cognitive inferences in the Movie for the Assessment of Social Cognition. MDMA produced subjective ‘empathogenic’ effects, such as drug liking, closeness to others, openness and trust.