Contents I. Introduction
Interest has grown recently in emerging prosthetic therapies for conventionally-untreatable neurological conditions, such as epilepsy [1], Parkinson's disease [2], depression [3], and motor impairments [4]. Researchers are exploring the brain–machine interface to translate physiological activity and neuromodulation into machine language for therapeutic purposes. Brain signal monitoring, clinical state analysis and low-power dissipation in prosthetic devices for long-term treatment are key challenges for emerging prosthetic therapies. Epilepsy, which affects approximately 60 million people worldwide, is the second most common chronic neurological condition. It is characterized by a predisposition to unprovoked recurrent seizures. Despite the existence of a number of anticonvulsants, of patients continue to have disabling seizures. Half of them may benefit from epilepsy surgery if the epileptogenic zone (EZ) can be identified and resected without harm. Others, however, are not good surgical candidates. Due to the limited spatial or temporal resolution of currently available noninvasive localization techniques, accurate delineation of the EZ may sometimes be arduous, particularly in patients with nonlesional refractory epilepsy [5], [6]. Moreover, many patients have an extensive area of epileptogenicity, multifocal epileptic foci, or an EZ overlying eloquent areas (language, primary motor or visual regions) that cannot be resected without permanent sequelae [6]. Hence, there is a need for alternative treatment modalities.
