Changes in cortical excitability differentiate generalized and focal epilepsy

Abstract

OBJECTIVE: Different pathophysiological mechanisms related to the balance of cortical excitatory and inhibitory influences may underlie focal and generalized epilepsies. We used transcranial magnetic stimulation to search for interictal excitability differences between patients with idiopathic generalized epilepsy (IGE) and focal epilepsy. METHODS: Sixty-two drug-naive patients with newly diagnosed epilepsy (35 IGE, 27 focal epilepsy) were studied. In the latter group, the seizure focus was not located in the motor cortex. Motor threshold at rest, cortical silent period threshold, recovery curve analysis using paired-pulse stimulation at a number of interstimulus intervals), and cortical sil..