Bilateral cochlear implantation in children is becoming increasingly popular in an effort to improve the ability to localize sound sources and understand speech in the presence of interfering stimuli. However, compared to the performance of normally hearing listeners, the binaural advantages that listeners with bilateral cochlear implants receive are limited. Sources of limitations in binaural hearing are currently poorly understood but may include limitations with cochlear implant devices and limitations in auditory system processing of listeners. Stimulation through bilateral cochlear implants provides degraded binaural information relative to the original acoustic signal and may fail to foster binaural hearig in children. Improving knowledge on the sensitivity of children with cochlear implants to binaural cues is necessary for improving technology and treatment of children with cochlear implants. Binaural masking level differences of children with bilateral cochlear implants will be examined using direct electrical stimulation to bypass the clinical cochlear implants and present bilaterall coordinated stimuli. Binaural sensitivity of children with bilateral cochlear implants will be examined relative to adults with bilateral cochlear implants and children with normal hearing. In addition, binaural sensitivity of children with normal hearing will be examined relative to adults with normal hearing. Binaural masking level differences are a measure of the binaural advantage for signal detection in noise. Examination of binaural masking level differences is important as it will improve understanding of limitations in the binaural advantage for segregating speech from noise. This study will further the understanding of binaural sensitivity of children with bilateral cochlear implants by examining binaural masking level differences under stimulus conditions which are relevant to real-world auditory stimuli.
Aim 1 will examine the effect of stimulus bandwidth on binaural masking level differences using a single pair of left-right electrodes.
Aim 2 will examine the effect of distance between electrodes using two pairs of left-right electrodes. Findings from this study will be informative for advancing cochlear implant technology in ways such that children receive benefits and will improve understanding of the development of the auditory system.

Public Health Relevance

The goal of this research is to further understanding of binaural sensitivity of children with cochlear implants. Specifically, this work will improve understanding of the ability of children with cochlear implants to use binaural hearing for improved signal detection. Findings will inform on the potential of children with cochlear implants to benefit from binaural hearing through advances in technology and will inform on the development of the human auditory system.

Agency
National Institute of Health (NIH)
Institute
National Institute on Deafness and Other Communication Disorders (NIDCD)
Type
Predoctoral Individual National Research Service Award (F31)
Project #
1F31DC013238-01A1
Application #
8598337
Study Section
Special Emphasis Panel (ZDC1-SRB-Z (24))
Program Officer
Sklare, Dan
Project Start
2013-07-01
Project End
2016-06-30
Budget Start
2013-07-01
Budget End
2014-06-30
Support Year
1
Fiscal Year
2013
Total Cost
$30,550
Indirect Cost
Name
University of Wisconsin Madison
Department
Psychology
Type
Schools of Arts and Sciences
DUNS #
161202122
City
Madison
State
WI
Country
United States
Zip Code
53715
Todd, Ann E; Goupell, Matthew J; Litovsky, Ruth Y (2017) The Relationship Between Intensity Coding and Binaural Sensitivity in Adults With Cochlear Implants. Ear Hear 38:e128-e141
Todd, Ann E; Goupell, Matthew J; Litovsky, Ruth Y (2016) Binaural release from masking with single- and multi-electrode stimulation in children with cochlear implants. J Acoust Soc Am 140:59