Effects of antiepileptic drugs on reaction time, attention, and impulsivity in children.

Abstract

Simple, choice, and complex reaction times, attention (variability of responses and omission errors), and impulsivity (commission and wrong-hand errors on choice and complex reaction time) were repeatedly measured in 111 epileptic children, aged 5 to 13 years, tested a total of 232 times. Antiepileptic drugs (AEDs) were started, stopped, and adjusted throughout the study period, for a variety of clinical indications, and AED serum levels were monitored. The relationship of performance to AED serum level was examined. Overall the nonspecific effect of AEDs was minimal: higher total serum levels of AEDs correlated with more impulsive errors on complex reaction time testing only. In contrast, in 54 children receiving carbamazepine monotherapy, we found a dose-related beneficial effect upon reaction time, with higher serum levels associated with faster responses and fewer omission errors, particularly on complex reaction time. Phenobarbital caused minimal dose-related effects: only variability and impulsive errors increased with increasing serum levels, and only on one segment of the test (73 subjects).