Objective: This protocol will test the hypothesis that the 3-Hz spike-wave discharges seen in absence epilepsy originate in the thalamus. We will use an emerging modality, magnetoencephalograpy (MEG), to test this hypothesis. Study Population: 33 patients with absence seizures. Design: This is a non-invasive imaging study that involves a 275-channel whole head MEG recording and a structural MRI for co-registration of MEG data. Outcome Measure: The primary outcome measure is the source localization of spike-wave discharges on magnetoencephalography.
- INCLUSION CRITERIA: 1. Age 7-35 2. Absence of seizures based on clinical and electroenecephalography data. Patients who have other seizure types (myoclonic, generalized tonic-clonic) in addition to absence seizures may be included. 3. Patients who have other neurologic disorders may be included, as long as they are able to consent/assent. EXCLUSION CRITERIA: 1. Contraindications to MEG studies (Dental braces, permanent retainers, metal dental caps/crowns/fillings) 2. Contraindications to MRI studies (such as pacemakers, cochlear devices, surgical clips, metallic implants, orthopedic pins, shrapnel, permanent eyeliner, vagus nerve stimulator) 3. Claustrophobia or anxiety disorders exacerbated by MRI 4. Pregnancy 5. Inability to provide consent/assent