On each trial, two lotteries were displayed, showing the associated probability and magnitude of the possible outcome for each. On each trial, participants chose one of the two lotteries, and the outcome was revealed. Choice behaviour was highly sensitive to the expected value of the two gambles in both the gain and loss domains. This sensitivity to expected value was attenuated in the group with gambling disorder.
The group with gambling disorder used both probability and magnitude information less, and this impairment was greater for probability information. By contrast, they used prior feedback win vs loss to inform their next choice, despite the independence of each trial.
Within the gambling disorder group, problem gambling severity and trait gambling-related cognitions independently predicted reduced sensitivity to expected value. The majority of observed effects were consistent across both gain and loss domains. Our results provide a thorough characterization of decision processes in gain and loss domains in gambling disorder, and place these problems in the context of theoretical constructs from behavioural economics.
All forms of gambling entail integrating information about the probability and magnitude of rewards in order to decide whether and how much to gamble. This information may be explicit e. The first has found that groups with disordered gambling make suboptimal i. In the Cambridge Gamble Task, where participants choose between two probabilities, and are therefore not required to integrate magnitude information, participants with gambling disorder also make more suboptimal choices Limbrick-Oldfield et al.
Much of the research investigating risky decision-making in gambling disorder has employed mixed gambles i. Aversive processing has received less attention, despite the recognition that altered processing of loss and negative consequences could contribute to gambling disorder Brunborg et al.
