Colloque

Development of Cochlear Implants: Optimization of Spatiotemporally Patterned Electrical Stimulation

M.M. Merzenich

Membre a labase

M.M. Merzenich

Résumé du colloque

One important approach in the development of cochlear implants has been the attempt to simulate normal distributions of auditory nerve representations of inner ear-derived speech by a spatiotemporally patterned electrical stimulation. There are at least five important factors that underlie optimization of this simulation approach (and must be achieved simultaneously). a) Electrodes must provide discrete spatial stimulation control. b) Electrode arrays must concentrate and an adequate number of stimulating, discrete elements across an adequate number of cochleotopically related stimulations sites. c) Stimulus waveform control and/or the multiple channel coding strategy must be used to generate at least local reproduction of auditory spectral detail. d) Current information and other temporal interaction effects severely limit simplifications of temporal detail. e) Simulation control must be achieved by the use of electrode arrays whose stimulating elements can be accurately (and non-traumatically) positioned. One largely overlooked aspect of this simulation approach has been the consideration of the specific relevance of spatiotemporal nerve array representational details for the self-organizing speech-representation machinery of the central auditory nervous system. In fact, these understood central nervous system factors obviously largely determine the utility of a given nervous system stimulation strategy. We have studied these five issues of multiple-channel electrode development, as well as the nature of self-organizing speech representational constructs in the central auditory nervous system.