Magnetic stimulation of the brain in generalized epilepsy: Reversal of cortical hyperexcitability by anticonvulsants

Abstract

Observations on experimental models suggest that diffuse cortical hyperexcitability is an important abnormality in the generalized epilepsies. We used the threshold for transcranial magnetic stimulation as an index of motor cortical excitability in 89 neurologically normal control subjects and 56 patients with idiopathic generalized epilepsy (20 untreated and 36 chronically treated with anticonvulsants). Magnetic stimulation was repeated in 10 patients after valproate monotherapy had been commenced and in 23 control subjects. The threshold intensity was significantly lower in the untreated patients (46 ± 5% [mean ± 95% confidence interval]) than in the control subjects (56 ± 2%). Treated pat..