Background and aimsIndividuals with gambling disorder display increased levels of risk-taking, but it is not known if it is associated with an altered subjective valuation of gains and/or losses, perception of their probabilities, or integration of these sources of information into expected value.MethodsParticipants with gambling disorder (n = 48) were compared with a healthy comparison group (n = 35) on a two-choice lottery task that involved either gains-only or losses-only gambles. 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.ResultsChoice 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.Discussion and ConclusionsOur 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.

Taken together, these findings suggest that the reduction in LPL activity, partly due to the decrease of plasma LPL concentration after TAC administration may be an explanation for hypertriglyceridemia observed in patients administered TAC.

Gambling has longstanding links with excitement and physiological arousal, but prior research has not considered (a) gamblers’ ability to detect internal physiological signals, or (b) markers of parasympathetic functioning. The present study measured interoception in individuals with gambling disorder, using self‐report measures and a heartbeat counting task administered at rest. Resting state respiratory sinus arrhythmia (RSA), an index of heart rate variability, was measured as a proxy for parasympathetic control and emotional regulation capacity. In a case‐control design, 50 individuals with gambling disorder were compared against 35 controls without gambling problems. Participants completed two self‐report measures of bodily awareness and a behavioral test of heartbeat counting. A resting state electrocardiogram (5 min) was used to calculate RSA. There were no significant differences on the self‐report or behavioral interoception probes. The group with gambling disorder displayed significantly reduced RSA, which at face value is consistent with reduced parasympathetic control. However, the group difference in RSA did not survive controlling for age and smoking status, as established predictors of heart rate variability. Our findings do not support any changes in interoceptive processing in people with gambling disorder, at least under resting conditions. Our observation that group differences in RSA are partly explained by smoking behavior highlights the importance of controlling for nicotine use in future research characterizing physiological functioning and emotional regulation in disordered gambling.

No abstract