Auditory Prosthesis with a Penetrating Nerve Array

Wednesday, June 13, 2007 - 7:00 p.m. to Thursday, June 14, 2007 - 7:55 p.m.

Grand Rounds – Sponsored by the Department of Otolaryngology - Head and Neck Surgery

Featuring John Middlebrooks, Ph.D.
Professor, Otolaryngology and Biomedical Engineering
MedicineSchool and College of Engineering
The University of Michigan at Ann Arbor

Location: UC Irvine Medical Center Building 33 - Dugan-Brauel Conference Room

Questions can be directed to Abby Copeland at or 949.824.9107

A conventional cochlear implant lies within a volume of electrically conductive fluid, separated from auditory neurons by a bony wall. Not surprisingly, thresholds for nerve activation are high and access to frequency-specific nerve-fiber populations is blunted. We are evaluating in an animal model an alternative mode of auditory prosthesis: a multi-electrode array inserted across the trunk of the auditory nerve. Early results are promising. Compared to a conventional cochlear implant, intra-neural stimulation provides more frequency-specific stimulation across the entire frequency range of hearing, as much as 50-fold lower thresholds, substantially reduced between-channel interaction, and enhanced preservation of residual hearing. We are taking initial steps toward translating this approach to human trials.