Drug Effects on Interpersonal Interaction

Paired-partner, within-subject design with three sessions: MDMA+conversation with Person A, placebo+conversation with Person B, and a post-test online session assessing partner preference; drug/placebo order counterbalanced and partners same-sex.

Primary outcomes are self-rated feelings of closeness and connection after each drug session and at the online test; participants are fully debriefed after study completion.