Study of an External Responsive Neurostimulator System on Epileptiform Activity

Inclusion Criteria: Subject is undergoing evaluation for epilepsy surgery in a manner consistent with the Surgery for Epilepsy, NIH Consensus Statement, 1990 Mar 19-21; 8(2); 1-20. Subject is implanted with intracranial electrodes. Subject is under constant medical supervision while implanted with the intracranial electrodes. Subject is twelve (12) years of age or older. Exclusion Criteria: Subject is pregnant. Subject has a clinically significant or unstable medical condition that, in the opinion of the investigator, would make it inadvisable for the individual to participate. Subject has a progressive central nervous system disease or serious acute or ongoing systemic illnesses. Subject has an active psychosis, severe depression, suicidal ideation or psychiatric conditions associated with impaired judgment. Subject is considered at high risk, for any reason, by any of the investigators. Subject is implanted with a medical device that might interfere with the eRNS. (This includes, but is not limited to direct brain neurostimulators, pacemakers, implantable cardiac defibrillators, spinal cord stimulators, vagal nerve stimulators, cochlear implants)