Participation for all individuals will last 4 months. Assessments will occur at baseline, and weeks 1, 2, 4, 8, and 12. Buprenorphine induction will begin at the completion of the second scan; follow-up medical visits will align with study assessments on weeks 1, 2, 4, 8 and 12. All participants will receive 16 weeks of buprenorphine (the final 4 of these 16 weeks will include a taper).