Abstract
OBJECTIVE: Motivational models of alcohol use emphasize that drinking motives (enhancement, coping, social, and conformity) drive alcohol consumption. However, few studies have directly tested how drinking motives relate to acute responses to alcohol, and existing studies typically omit social motives and expectancy effects and rely on solitary drinking paradigms with limited ecological validity. This preregistered study addresses these gaps by testing associations between drinking motives and alcohol's acute effects on emotions and social outcomes in a large, multiperson alcohol administration study with placebo control. METHOD: Heavy-drinking young adults (N = 393; 50% female) completed the Drinking Motives Questionnaire-Revised and were grouped into 131 triads of unacquainted individuals. Groups consumed either alcohol (males: 0.82 g/kg; females: 0.74 g/kg) or placebo over 36 min. Interactions were video-recorded and coded for facial expressions (e.g., using Ekman's Facial Action Coding System), speech, and laughter. Postdrink, participants reported affect, stimulation, and social bonding. RESULTS: Multilevel structural equation modeling showed that many associations between drinking motives and acute alcohol responses, particularly enhanced stimulation and positive affect linked to enhancement, coping, and social motives, occurred similarly in both alcohol and placebo conditions, highlighting the significant role of expectancy effects. However, coping motives uniquely predicted greater perceived relief of negative affect specifically in the alcohol condition, even after accounting for other motives, despite no evidence of actual reductions in negative affect from pre- to postdrinking. CONCLUSIONS: Findings underscore the value of considering expectancy effects and ecologically valid contexts when examining how motives shape alcohol responses. (PsycInfo Database Record (c) 2026 APA, all rights reserved).