The emerging field of psychedelic medicine holds significant promise for addressing devastating and difficult-to-treat behavioral health conditions. Yet outcomes can vary widely between participants, and researchers still do not fully understand the mechanism of action behind many of the therapeutic effects—an understanding essential to delivering safe and effective psychedelic medicine at scale. This study aims to determine the extent to which positive outcomes from psychedelic-assisted therapy depend on drug-induced plasticity synergizing with supportive contextual conditions, also known as "set and setting." By integrating in-session biological and behavioral data, the study will work toward a validated model for predicting individual response to treatment.