"Should've known better": Counterfactual processing in disordered gambling.

Counterfactual thinking is a component of human decision-making that entails "if only" thinking about unselected choices and outcomes. It is associated with strong emotional responses of regret (when the obtained outcome is inferior to the counterfactual) and relief (vice versa). Counterfactual thinking may play a role in various cognitive phenomena in disordered gambling, such as the effects of near-misses. This study compared individuals with gambling disorder (n = 46) and healthy controls (n = 25) on a behavioural economic choice task that entailed choosing between two gambles, designed to measure counterfactual thinking. Participants provided affect ratings following both the obtained and the non-obtained outcomes. Choices were analyzed using a computational model that derived parameters reflecting sensitivity to expected value, risk variance, and anticipated regret. In the computational choice model, the group with gambling disorder showed increased sensitivity to anticipated regret, reduced sensitivity to expected value, and increased preference for high risk-variance gambles. On the affect ratings, the group with gambling disorder displayed blunted emotional sensitivity to obtained and counterfactual outcomes. Effect sizes of the group differences were modest. Participants with gambling disorder show wide-ranging alterations in decision-making processes and emotional reactivity to choice outcomes. Altered sensitivity to anticipatory regret in gambling disorder may contribute to the development of gambling-related cognitive distortions, and the influences of gambling marketing.

Gambling disorder is associated with reduced sensitivity to expected value during risky choice.

BACKGROUND AND AIMS: Individuals 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. METHODS: Participants 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. RESULTS: 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. DISCUSSION AND CONCLUSIONS: 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.

Interoception and respiratory sinus arrhythmia in gambling disorder.

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.

Tacrolimus-induced elevation in plasma triglyceride concentrations after administration to renal transplant patients is partially due to a decrease in lipoprotein lipase activity and plasma concentrations.

BACKGROUND: Hyperlipidemia is a frequent and persistent complication in solid organ transplant recipients, leading to the high occurrence of cardiovascular disease in this patient population. Lipid abnormalities including increased total cholesterol, triglycerides (TG), and low-density lipoprotein-cholesterol have been reported frequently in transplantation patients and a variety of immunosuppressive therapies seem to be one of the main factors that influence posttransplant lipidemic profiles. For many years, tacrolimus (TAC) has been used as an immunosuppressive drug in transplantation. The aim of our investigation was to determine the effect of TAC administration on the plasma lipid profile and some key regulatory proteins of plasma lipid metabolism including cholesterol ester transfer protein, hepatic lipase and lipoprotein lipase (LPL) within renal transplant patients. METHODS: Twenty-five renal transplant patients were recruited and received TAC therapy, of which nine of these patients were treated with statin therapy for dyslipidemia. The effects of TAC on plasma total cholesterol, TG, HDL-C, low-density lipoprotein-cholesterol, cholesterol ester transfer protein, hepatic lipase and LPL concentration and activity were determined from patients plasma samples collected before the transplant surgery (baseline), and weekly for four consecutive weeks after surgery and TAC administration. RESULTS: We observed that TAC significantly increases plasma TG concentrations and reduces LPL plasma concentration and activity in renal transplant patients, independent of any lipid lowering drug treatment patients received. CONCLUSIONS: 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.