Executive deficits in generalized and extrafrontal partial epilepsy: long versus short seizure-free periods

Abstract

Objective: The goal of this study was to examine the influence of seizure freedom on executive function in outpatients with generalized epilepsy and extrafrontal partial epilepsy. Recent investigations of cognitive function in epilepsy have revealed executive deficits in persons with focal temporal as well as generalized epilepsies. Additional studies have suggested an influence of seizure freedom on cognitive function.

Methods: Thirty-five consecutive outpatients were divided into seizure free <or= 3 months (n=18) and seizure free >3 months (n=17). The neuropsychological tests administered included: verbal fluency tasks, the Cognitive Estimation Test, the Hayling and Brixton Test, and the Behavioural Assessment of the Dysexecutive Syndrome (BADS) battery. Both patient groups were compared with matched healthy controls (n=16).

Results: The extensive testing revealed significant differences between patients with shorter seizure-free periods and healthy controls with respect to overall errors and phonemic verbal fluency, response suppression, and BADS overall profile scores. Subjects seizure free >3 months exhibited a trend toward impairment in the phonemic fluency task only.

Conclusions: The results suggest that deficits in executive function were present in patients with extrafrontal partial epilepsy and generalized epilepsy, indicating the potential influence of epileptic activity on the ability to focus on relevant information and switch attention to other relevant information, to plan tasks and subtasks, and to check on and encode working memory content. The results also suggest that those deficits may be more pronounced in patients with relatively short seizure-free periods.