Implantable Neural Sensors for Brain Machine Interface

Implantable neural sensors are the enabling devices for neural prosthesis that has the potential to restore lost functions in neurologically impaired humans. Movement loss due to a neurological disability is devastating, and has produced a large patient population for whom there are limited available therapeutic options. Permanently implanted cortical microelectrodes measure signals from regions of the brain that are directly related to intended movements. In conjunction with newly developed decoding techniques using probabilistic analysis, good correlation has been achieved for the arm movement of a non-human primate between the signals recorded directly from the brain and the real physical action by the animal. A recent culmination of research into brain sensor development has been human clinical trials where intention-driven neuronal ensemble activity has been converted into a control signal that enables a patient with tetraplegia to perform useful tasks. In this chapter, we describe the recent progress in the development of advanced brain implantable microsystems for the brain machine interface (BMI) that includes not only the optimal system architecture with ultracompact low power electronics, but also new technologies for a broad-band neural data transmission as well as an efficient power delivery to the brain implantable active electronics.