Title: Restoration of Spatial Hearing in Adult Cochlear Implant Users with Single-Sided Deafness
Legend: Tinnitus Handicap Inventory – On a scale of 1-10, having a cochlear implant (CI) reduced tinnitus reports in some of the patients. Sound Localization – Root mean square (RMS) localization error values shown for each subject; Acoustic vs. Acoustic+CI conditions. For comparison, data from normal hearing (grey region) and bilateral CI participants (purple region).
Citation: Litovsky RY, Mous K, Godar S, Kan A, Misurelli S, Lee D (In Press). Restoration of Spatial Hearing in Adult Cochlear Implant Users with Single-Sided Deafness. Hearing Research.
Abstract: Study Motivation – Many people with single-sided deafness have tinnitus in the deaf ear (and normal hearing in the other ear). We are conducting a clinical trial in collaboration with surgeons at Harvard Medical School, to determine if a CI in the deaf ear provides: (A) relief from tinnitus due to the electrical stimulation, and (B) improved ability to localize sounds. Preliminary results from 9 subjects who received an implant and 6 subjects who are planning to be implanted are shown. Results – In about half of patients with a CI, tinnitus was reduced when using the CI compared to the acoustic ear alone (top panel). Sound localization errors were reduced with the addition of the CI in 7/9 patients.
About the Lab: Research in the Litovsky lab focuses on the ability of children and adults to hear in complex auditory environments (e.g., classrooms, restaurants, playgrounds, and “cocktail parties”). We are typically faced with the challenge of interpreting sounds as they reach the ears, learning to ignore echoes and other irrelevant, distracting signals. The brain has specialized circuits that compute sound location and separate important sounds from background noise. We study the contribution of binaural hearing and the limitations that are experienced by people with hearing loss. In particular, we focus on a unique population of people who are deaf and use cochlear implants. In addition to studying spatial hearing, such as sound localization skills and speech understanding in noise, we are interested in cognitive development and its implications for auditory processing. Another aspect of our research focuses on the effect that challenging listening situations has on listening effort, and the amount of cognitive load exerted during psychophysical testing. Finally, our reverse engineering approaches focus on possible ways in which bilateral cochlear implants can be improved by synchronizing the devices across the ears and utilizing novel strategies to stimulate electrodes in the cochlea that restore near-normal binaural hearing.