The effects of varying the number of cochlear implant electrodes on speech perception

The purpose of this investigation was to evaluate the speech perception of a patient fitted with a multichannel processor under different electrode conditions. The subject was evaluated with the speech processor programmed with electrode arrays varying in number from one to nineteen. The results suggested that with an increased number of programmed electrodes, the subject's speech perception improved. Comparisons were also made among three speech processing strategies. The processor was programmed with: (1) one electrode pair that provided fundamental frequency information; (2) nineteen electrode paris that provided fundamental frequency plus second formant information (F0/F2); and (3) nineteen electrode paris that provided fundamental frequency plus first and second formant information (F0/F1F2). The subject did better with the F0/F2 strategy compared to the F0 strategy and best with the F0/F1F2 strategy.