The Protocol for: Do peers enhance alcohol use outcomes in group motivational interviewing? A translational clinical trial investigating brain synchrony in underage emerging adults during a fMRI hyperscanning task and its association with 12 month alcohol use reductions.

Background and Aims: Alcohol is the top substance used by US emerging adults under legal drinking age (underage emerging adults; U-EA; ages 18-19). U-EA are unlikely to seek or receive indicated alcohol interventions. It is imperative to find brief, effective interventions to reduce U-EA drinking. Developmental neuroscience reflects that peers hold higher neural salience during adolescence, as evidenced by differential neural response with real and/or simulated peers, even when those peers were not friends, and particularly in the context of alcohol. Peers also activate positive (prosocial) neural and behavioral responses among adolescents. The role of positive, prosocial peer feedback is consequential given that the most widely-used U-EA platforms for adolescent addiction intervention are group-based interventions. We propose functional magnetic resonance imaging (fMRI) hyperscanning (tandem dyadic scanning) to evaluate U-EA brain response in the underexamined, but widely-utilized, group motivational interviewing (MI). We will examine associations between youth brain synchrony generated in an fMRI hyperscanning task and alcohol use reductions at 12 month follow-up. We hypothesize that greater neural alignment in the social cognition network during positive, prosocial peer interactions (peer-directed change talk) will be associated with greater post-intervention behavior change (lower number of past month drinking days) at 12 months. Design: Within-subjects. Setting: UConn Health and UT-Dallas. Participants: This study will enroll n=248 U-EA (ages 18-19) with ≥1 past month binge drinking event (4/3 standard drinks per occasion for males/females) via community and campus recruitment. Intervention and comparator: Group MI (no comparator; within-subjects). Measurements: This protocol will utilize synchronized fMRI (hyperscanning) to examine positive, prosocial peer-directed health promotive language (peer-directed change talk) directly generated during and extracted from the group MI session. Primary outcomes include fMRI-based hyperscanning metrics (BOLD synchrony in social cognition networks) and behavioral measures (past month alcohol use days measured viaTimeline Followback; TLFB) at 12 months. Secondary outcomes will evaluate the same relationship at 3- and 6-months. Comment: This translational study is crucial for making meaningful gains in adolescent addiction intervention. We could find no peer-reviewed studies examining fMRI hyperscanning in an adolescent addiction intervention context. And, fMRI hyperscanning is at the forefront of interactive, dyadic youth research in socially-relevant and ecologically valid settings. In addition, due to the limited empirical evaluations of group interventions, including group MI, the use of fMRI hyperscanning is timely and offers a unique examination with high clinical impact for young people struggling with addiction.