Close Relationships and Alcohol Use Disorder Risk - Models of alcohol use disorder (AUD) risk increasingly conceptualize relationship factors as being critical to the understanding of problem drinking. A substantial literature exists linking lower relationship quality (e.g., partner conflict, relationship dissatisfaction, insecure attachment) to the development of AUD, and interventions focused on improving relationship quality have demonstrated some success. However, we lack an understanding of how and why lower relationship quality shapes AUD risk over time. A better understanding of such mechanisms could have broad implications for understanding AUD risk in close relationships more generally. The proposed project merges insights from the alcohol administration literature and research conducted by social psychologists with expertise in close relationships to offer a novel conceptual model that depicts how lower relationship quality impacts the way that couples experience alcohol, which in turn sets them on a path toward heavier alcohol consumption and the development of AUD symptoms. More specifically, we predict that couples with lower (vs. higher) relationship quality experience heightened alcohol-induced social bonding and emotional rewards, and that this increased sensitivity to alcohol’s social and emotional rewards in couples with lower relationship quality is a key mechanism that drives problematic drinking over time, which then increases risk for AUD. Two-hundred-fifty-two couples (N=504 young adult drinkers; aged 21-30) will drink together over 36-min a moderate dose of alcohol (males: 0.82 g/kg; females: 0.74 g/kg) or a placebo beverage. Alcohol reinforcement (e.g., social bonding, reduced social tension) will be assessed during a free interaction period and a conflict resolution discussion using a broad range of measures across multiple response systems (e.g., self-reports, observational measures). Drinking behavior, alcohol reinforcement, acute alcohol-related problems, and relationship functioning will be assessed in daily life during three subsequent ecological momentary assessment bursts, and AUD symptoms will be assessed at baseline and at 12-month follow-up. We predict 1) an alcohol by relationship quality interaction, such that alcohol’s social and emotional reinforcing effects at the individual and dyad-levels, measured across multiple response systems, will be stronger in lower (vs. higher) RQ couples, 2) alcohol’s social and emotional reinforcing effects in real-world contexts will vary across couples as a function of the blood alcohol curve (BAC) and partner drinking status, such that couples with lower (vs. higher) RQ will experience stronger reinforcing effects on the ascending limb of the BAC when both members are drinking together (vs. when couples are together but only one member is drinking), 3) higher alcohol reinforcement on the ascending limb of the BAC will predict heavier alcohol consumption and more acute alcohol problems (both within-person and across-partners), and 4) lab-based and real-world measures of alcohol reinforcement will prospectively predict heavier drinking and more AUD symptoms at 12-month follow-up, particularly for lower RQ couples. This project integrates two prominent literatures that have not been connected before (i.e., social psychological theory and research in couples with longitudinal alcohol administration work) and promises to have broad conceptual, methodological, and clinical implications..
