Seamless interfacing with the human nervous system is likely to have signiﬁcant implications for enhanced understanding of its function, as well as exciting therapeutic potential. However, it is important to recognize the biological landscape setting the design criteria for any engineering interface to the nervous system. The nervous system of mammalian species is incredibly complex, but can be divided into two basic parts, central and peripheral. The central nervous system (CNS) is composed of the brain and spinal cord, while the peripheral system (PNS) consists of sensory, motor, and pain ﬁbers that connect the body’s extremities to the spinal cord and the brain. Therefore there exists a neuroanatomical map that is intricate as well as a neurochemical map that has great, micron level topographical speciﬁcity that any sensor would have to accommodate. Essentially, the brain has a high cell density and particular regions of the cortex are responsible for speciﬁc functions.