RecruitingPhase 4Drug trialStimulant vs. Non-stimulant Treatments and Reward Processing in Drug-naive Youth at SUD RiskThe study team will examine the effects of FDA approved stimulant and non-stimulant medications for ADHD, among youth with ADHD and with and without Oppositional Defiant Disorder (ODD) or Conduct Disorder (CD), on reward systems of the brain using fMRI.