A controversial issue in epilepsy research involves the effects of anticonvulsant drugs on cognitive function and behavior. The article by Dikmen and colleagues1 in this issue of The Journal is an important contribution to the subject, especially as it addresses the issue in nonepileptic subjects. Thus, one problem of much work in this area relates to experimental design when the illness in question contaminates the results of any study. Seizures thus impair cognition, and anticonvulsant drugs, by changing seizure frequency, can render interpretation of data difficult. There are several ways to tackle this; one relates to using nonepileptic populations.
An earlier attempt in this direction was made by Thompson and colleagues.2 They used healthy volunteers who were prescribed anticonvulsant drugs in clinically equivalent doses for 14 days, testing cognitive function in a double-blind crossover study against placebo. Phenytoin significantly impaired performance on a variety of tasks, and in