Related Experiment Video
Updated: Jun 25, 2026

Systematic Hearing Performance Evaluation Process for Adolescents with Cochlear Implantation at Early Ages
Published on: March 24, 2023
Simultaneous bilateral cochlear implantation: prospective study in adults
Dawn Burton Koch1, Sigfrid D Soli, Mark Downing
1House Ear Institute, Los Angeles, California, United States.
Abstract:
Normal-hearing listeners gain important everyday benefits from having two ears, particularly for determining where sounds come from and for understanding speech in noisy environments. Users of two cochlear implants may have the opportunity to experience some of these bilateral advantages. The primary aim of this study was to document bilateral versus unilateral listening benefit in 15 postlinguistically deafened adults implanted simultaneously with two Harmony(®) (HiRes 90K(®)) cochlear implants. Speech perception (in quiet and in noise) and localization accuracy were assessed for each ear alone and both ears together. Subjects showed improved sound localization and better speech perception in quiet and in noise when using two implants compared with using one implant alone.
