Evaluation of MDMA on Startle Response

The goal of this clinical trial is to learn if MDMA impacts startle response in healthy participants. The main question it aims to answer is: Does MDMA impact participant's performance on a startle test? Researchers will compare healthy volunteers who have taken MDMA to those who have taken placebo. Participants will first undergo a 1-hour startle test. The next day, they will be randomized to receive either MDMA or placebo followed by another startle test and vitals signs and blood measurements. Participants will return the next day for a final startle test. Their sleep will be tracked by a Fitbit device.