Cochlear Implant Electrophysiology Laboratory

Paul Abbas, Ph.D., Carolyn J Brown, Ph.D., Directors

The Human Electrophysiology Laboratory, located in the Pomerantz Family Pavilion, Department of Otolaryngology. Experiments in the laboratory focus on the measurement of electrically evoked potentials from the auditory system in patients who have a cochlear implant. Individuals with cochlear implants exhibit a wide range of performance with the device. Peripheral measures such as the electrically evoked compound action potential (ECAP) recorded using telemetry systems incorporated into commercial cochlear implants have become important tools for both initial programming and monitoring of young children. We are also doing studies measuring cortically evoked responses to stimulation through the implant. Our goal is to use the results of such studies to more fully characterize the differences we observe across individuals and use that information to assist with clinical decision making, inform candidate selection and influence the ways the speech processor is programmed in order to maximize performance for an individual user.

Our work has focused on the use of objective measures to program cochlear implants in pediatric populations. We have also done a number of studies examining issues such as channel interaction among stimulated electrodes as well as studies of adaptation or refractory properties in the neural response. We are studying the variations across individuals but also have focused on changes that occur over time with continued implant use in both pediatric as well as geriatric populations. Finally while much of our work is in patients who use standard cochlear implants, we also use these techniques in new populations of cochlear implant users such as those patients who use the Hybrid cochlear implant system and patients who receive bilateral cochlear implants.