Cognitive processes underlying impaired decision-making under uncertainty in gambling disorder

Objective: Pathological gamblers display at the Iowa Gambling Task (IGT) a strong preference for choices featuring high immediate rewards, but higher unpredictable and more delayed losses. The present study aimed, by applying the Expectancy-Valence (EV) model to the IGT, at identifying impaired components of decision-making under uncertainty in pathological gamblers. Methods: Twenty pathological gamblers and 20 non-gamblers performed the IGT. The EV model breaks down IGT performance into three cognitive processes: (i) the subjective weight that the individual assigns to gains versus losses (gain/loss parameter), (ii) the degree of prominence given to recently-obtained information, compared to past experience (recency parameter), and (iii) the consistency between learning and responding (consistency parameter). Results: Pathological gamblers obtained higher scores on the gain/loss parameter as compared to controls, indicating higher sensitivity to monetary gains. This measure was also correlated with the degree of gambling dependence severity. No between-group difference was observed in the recency and the consistency parameters. Conclusion: These findings suggest that pathological gamblers' strong preference for choices featuring high rewards but higher losses during the IGT is due to hypersensitivity for large monetary gains, which might reflect a hypersensitivity in their reward systems. In contrast, we found in pathological gamblers no evidence of inability to integrate information across time, a function that has been shown previously to be linked to damage in the prefrontal cortex. Published by Elsevier Ltd.