A-153 Working Memory Performance and Brain Activity in the context of Opioid Withdrawal and Relapse

Abstract

Abstract Objective Working memory (WM) deficits are associated with opioid use disorder (OUD). However, little research addresses WM during withdrawal. We used the N-back WM paradigm to assess whether differences exist between persons in withdrawal versus stable opioid doses. We also examined whether N-back performance or associated brain activity during either withdrawal or satiation predict subsequent abstinence versus relapse. Method We evaluated N-Back performance and associated brain function of 20 OUD patients during 3 T fMRI. Participants were actively using opioids during the first scan (SOWS M = 8.10, SD = 9.22) and abstained 24 hours before the second scan (SOWS M = 28.26, SD = 11.64), buprenorphine treatment began afterwards. Twelve participants (age: M = 33.92, SD = 5.99) completed both scans and were included in within-subject contrasts. Sixteen participants (age: M = 34.38, SD = 5.38) completed at least one scan and were evaluated on whether brain activation or performance was associated with relapse. Results Paired-sample t-tests revealed no significant difference on N-back accuracy (0-back: t = 0.78, p = .45, d = 0.23; 2-back: t = −0.28, p = .78, d = 0.08) or brain activation (2-back versus 0-back) across regions of interest (ROIs) associated with WM in prior studies between satiated and abstinent assessments (ts < 0.5, ps > .05). Contrasting relapsing and abstinent groups at follow-up revealed no significant difference in N-back accuracy (0-back: t = −0.30, p = .77, d = 0.14; 2-back: t = 0.43, p = .67, d = 0.22) or associated ROI brain activation (ts < 1.29, ps > .05). Conclusion This is the first investigation of brain and behavioral measures of WM in opiate withdrawal and relapse. No significant differences were found, and effect sizes were small. Further research that investigates direct (compensatory activation) and task-indirect systems (default network, motivation) during cognitive challenges is needed.