Chenji Gu is a Research Assistant at the Gambling Research, Education and Treatment Centre at Swansea University. Her research focuses on the cognitive processes involved in gambling-related decision-making and the individual differences associated with gambling harm. Her current work uses behavioural tasks and computational modelling to examine how people process and respond to gambling-related information. Before joining Swansea, Chenji completed an MSc in Language Sciences and a BSc in Psychology at University College London.

Abstract

Behavioural economics of gambling harm: Gambling purchase demand and drift-diffusion modelling of value-based decision-making

Aims: Severe gambling harms affect around 0.5% of the UK population and are associated with significant psychological and financial consequences, but the cognitive mechanisms underlying persistent gambling remain unclear. This study combined behavioural economic assessment of gambling demand with value-based decision-making and hierarchical drift-diffusion modelling to examine whether gambling harm severity is associated with increased gambling valuation and disrupted decision-making processes specific to gambling-related choices.

Methods: One hundred and ten UK adults differing in self-reported gambling severity completed two online tasks. In a gambling purchase task, participants reported how many gambling activities they would purchase across escalating prices, providing indices of demand intensity and price sensitivity. In a value-based decision-making task, participants rated gambling and non-gambling images according to their preferences, then made forced choices between image pairs.

Results: Higher gambling severity predicted greater gambling consumption across prices, higher maximum expenditure, and more inelastic demand. Preference ratings for gambling images increased with severity, whereas non-gambling ratings did not. Hierarchical drift-diffusion modelling revealed generally lower boundary separation for gambling choices across the sample. Critically, higher severity was selectively associated with reduced drift rate in the gambling block, indicating impaired value discrimination for gambling-related stimuli.

Conclusions: Gambling harm severity was associated with both increased behavioural demand and altered value-based decision-making. Although gambling stimuli elicited faster and less cautious responding overall, higher gambling severity was specifically linked to impaired evidence accumulation for gambling-related choices. These findings suggest a disruption in how gambling-related value guides decision-making, with potential implications for understanding and treating gambling harm.