Bio Dr. Professor Kevin D. Brown is the Vice Chair and Joseph P. Riddle Distinguished Professor of Otolaryngology at the University of North Carolina School of Medicine. He is also the Chief of the Division of Otology and Neurotology and Executive Director of the Children's Cochlear Implant Center.
Summary Variability in cochlear implant design, including length of electrode and position within the cochlea (lateral wall or perimodiolar), coupled with variability in cochlea anatomy contributes to variable electrode location within the cochlea. This variability in turn impacts the frequency region neighboring a given electrode, termed the place-pitch relationship. Default manufacturer settings assign frequency to electrodes on the array without consideration of electrode location. As frequency presented by the electrode deviates from the place frequency at that location in the cochlea, variable degrees of mismatch can occur. We wished to determine the effect that frequency place-pitch mismatch has on speech perception outcomes. We utilized subjects with single-sided deafness to isolate this effect on speech perception in both quiet and noise. While there was only a modest effect of mismatch on speech perception in quiet, a significant negative effect of mismatch was seen on a subject’s ability to perceive speech in noise, persisting out to at least one year. This suggests that distortion of binaural cues by an inappropriate place-pitch location precludes optimal binaural processing necessary for speech perception in noise.