RecruitingEarly Phase 1Drug trialOpioid-Sparing and Pain-Reducing Properties of Syntocinon: A Dose-Effect DeterminationSome research suggests that administration of oxytocin with oxycodone may reduce its abuse liability and improve its ability to reduce pain. In a 6-session laboratory study, the investigators will be evaluating the effects of oxycodone and oxytocin (combined and separately, across sessions) on experimentally-induced pain, subjective effects, decision-making, and activation of different neural substrates.