Effects of probabilistic win-paired-cues on loss trials on risky choice in rats

Gambling Disorder affects 1.4 % of the global adult population and can result in detriments to physical, mental, and financial well-being. Electronic gambling machines may be more addictive than other forms of gambling. Electronic gambling machines present a series of audiovisual stimuli concurrently with winning and some losing outcomes. Previous research in human and non-human animals has found increased levels of risky choice when audiovisual stimuli are presented with wins compared to their absence. The present study was arranged to evaluate how a visual stimulus paired with winning outcomes, and presented on some losing outcomes, would influence risky choice in rats using a probability-discounting paradigm. A choice between a smaller, certain outcome and a larger, uncertain outcome (with changing probabilities) was presented. A visual cue was always presented with winning outcomes and was systematically implemented on a proportion of outcomes where a choice was made for the uncertain alternative, but no food reinforcement was delivered. Increases in risky choice were found when the win-associated stimulus was presented on half of all losing outcomes, relative to when it was omitted. Increases in risky choice were observable when choice was between relatively equal value choices and when the value of the smaller, certain alternative was only slightly higher than that of the larger, uncertain alternative. Risky choices were also more likely following a losing trial with the presentation of the win-paired cue than following a win or a loss without the win-paired cue. Implications in electronic gambling machines are discussed.