NEURAL ENCODING OF ELECTRICAL SIGNALS a

Research on the cochlear prosthesis is increasingly concerned with the nature of sounds that we encounter and how we might encode them for introduction through a cochlear prosthesis. As we progressively define the physiological and technical limitations on extracting, transforming, and introducing information from these sounds in electrical form, the rules relating the electrical waveforms used to drive a prosthesis and afferent neural activity become a central concern to prosthesis operation. These rules act at the interface between local electrical events and the response of neural membranes, giving rise to questions about stimulus encoding as well as the central processing leading to perception and responses. This is a selective review of published and ongoing research on some topics especially relevant to the encoding of signals presented through a cochlear prosthesis. Its purpose is to summarize in an organized manner information that we view as important for understanding and optimizing prosthesis operation. Data from our laboratories on animal and mathematical models form much of the matrix for the discussion that follows.