In sum, this study is the most extensive repeated human testing study of its kind, examining the adaptive processes underlying the development and maintenance of AUD. Alcohol-induced subjective stimulation increased over time, and euphoric processes did not wane as AUD symptoms emerged. Instead, these effects either stayed the same or increased, challenging the notion that conventional chronic tolerance to alcohol’s subjective effects plays a key role in escalation of excessive drinking. The findings are consistent with the incentive-sensitization theory as alcohol wanting increased over a decade in persons developing AUD. But study results were not consistent with the allostasis model of a progressive deficit in reward. In terms of prevention of alcohol problems, rather than a sole focus on tolerance, young adults might be informed that marked stimulant-like, pleasurable and appetitive effects after consuming alcohol are risk factors for the development and maintenance of addiction. Finally, pharmacological and behavioral interventions focused on reduce positive reinforcing effects and motivational salience may be crucial in medications development and the future treatment of AUD.
