Nature: An implant developed by neuroscientists at the New York University School of Medicine was able to reduce the duration of petit mal epileptic seizures in rats by 60%. The implant, which uses transcranial electrical stimulation, targets the brain’s outermost layer of neurons, which is highly excited during seizures. The implant differs in two respects from similar devices that are already coming to market. First, its electrodes do not penetrate the brain. Second, by monitoring brain and muscle activity, the implant does not have to apply therapeutic stimulation continually; it intervenes only when it detects a seizure.