The major treatment problems facing patients with epilepsy are resistance to drugs and unwanted side effects. Targeting treatment to a specific area of the brain immediately prior to and during a seizure would present a significant advancement. The goal of this project, which melds biology and engineering, is to develop a novel, cell-based neural prosthetic to electrically detect a seizure before it occurs and respond by stimulating transplanted cells to rapidly release GABA (a critical therapeutic target in epilepsy), thereby preventing the seizure.