Multiple studies have demonstrated that antiepileptic drug therapy may have consequences on cognitive function. Topiramate (TPM) is a new antiepileptic drug characterized by several mechanisms of action, which has proved to be clinically effective in the reduction of the quantity of crisis in epileptic patients. Clinical studies frequently report subjective cognitive complains, inconsistently sustained. The main objective of this study was to assess neuropsychological effects attributable to the addition of TPM to the current antiepileptic therapy, in patients with refractory partial epilepsy.