Objective: A substantial number of people reduce their consumption of alcohol in the absence of formal treatment; however, less is known about the mechanisms of change. The aim of this study is to explore whether constructs derived from behavioral economics and computational decision-modeling characterize the moderation of alcohol consumption that many heavy drinkers experience without treatment. Method: Between-subject, preregistered design. People who reside in the United Kingdom and who drink heavily (n = 60) or used to drink heavily but now consume alcohol in moderation (n = 60) were recruited. Participants completed self-report behavioral economic measures (alcohol demand and alcohol-related and alcohol-free reinforcement) and a two-alternative forced choice task in which they chose between two alcoholic (in one block) or two soft drink images (in a different block). A drift-diffusion model was fitted to responses from this task to yield the underlying parameters of value-based choice. Results: Compared to heavy drinkers, moderated drinkers had significantly lower alcohol demand, O max , p = .03, Cohen's d = .36; elasticity, p = .03, rank-biserial correlation (r rb ) = .21, and higher proportionate alcohol-free reinforcement ( p < .001, Cohen's d = .75). However, contrary to hypotheses, there were no robust between-group differences in value-based decision-making (VBDM) parameters. Conclusions: Self-report behavioral economic measures demonstrate that alcohol moderation without treatment is characterized by lowered alcohol demand and greater behavioral allocation to alcohol-free reinforcement, in line with behavioral economic theory. However, a computerized VBDM measure yielded inconclusive findings.
Public Health Significance StatementIt is common for people to reduce their consumption of alcohol, including those who consume alcohol heavily but are not dependent. This study highlights the importance of lowered alcohol demand and heightened behavioral allocation toward activities that do not involve alcohol. Findings may inform interventions for heavy drinkers who would like to moderate their alcohol consumption.