Dissociation between decision making under ambiguity and risk in patients with juvenile myoclonic epilepsy.

Introduction: Decision making (DM) is one aspect of impulsivity that can be defined by the ability to decide between two or more options in a given situation. To date, there are at least two types of DM that differ in the level of uncertainty, and how much information about consequences is provided. In this study, we aimed to evaluate the two domains of DM - under risk and ambiguous - with a comprehensive evaluation in a group of patients with juvenile myoclonic epilepsy (JME), and correlate with patients' characteristics, clinical variables, and neuropsychological evaluation for executive functions.

Methods: We evaluated 35 patients with JME and 39 healthy controls using the Iowa Gambling Task for DM under ambiguity and the Game Dice Task for DM under risk. We assessed the performance in Iowa Gambling Task and Game Dice Task through net scores, safe and risky choices, besides the type of decisions across time.

Results: Patients with JME had a higher number of risky choices compared to controls in the Game Dice Task. There was no significant difference between patients and controls in the Iowa Gambling Task. However, patients with higher seizure frequency had worse scores on decks C and D (safe choices) from the Iowa Gambling Task.

Conclusion: Patients with JME have worse performance on DM under risk. The same was not observed for DM under ambiguity. Epilepsy-related factors and the presence of psychiatric disorders, but not executive dysfunction, were associated with a lower tendency for safe choices. These findings showed a dissociation between DM processes in patients with JME and a tendency to make disadvantageous decisions with measurable risks.