In an embodiment, the invention relates to neural prosthetic devices in which control signals are based on the cognitive activity of the prosthetic user. The control signals may be used to control an array of external devices, such as prosthetics, computer systems, and speech synthesizers. Data obtained from a 4×4 mm patch of the posterial parietal cortex illustrated that a single neural recording array could decoded movements of a large extent of the body. Cognitive activity is functionally segregated between body parts.
