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.