Bilateral Cochlear Implant Processing of Coding Strategies With CCi-MOBILE, an Open-Source Research Platform

Area of Science:

• Audiology and Hearing Science
• Biomedical Engineering
• Neuroscience

Background:

• Cochlear implant (CI) users often struggle with sound localization and speaker identification, despite effective speech understanding in quiet.
• Bilateral and bimodal hearing strategies are increasingly adopted to enhance residual hearing and speech intelligibility in CI users.
• Accurate bilateral processing requires precise synchronization and fitting of algorithms between left and right cochlear implant channels to utilize interaural time and level difference (ITD and ILD) cues.

Purpose of the Study:

• To demonstrate and validate a custom-made CI research platform, CCi-MOBILE, for processing bilateral cochlear implant algorithms.
• To assess the platform's capability in capturing precise source localization information.
• To enable real-time testing of bilateral CI processing in naturalistic environments.

Main Methods:

• Development of the CCi-MOBILE custom-made CI research platform.
• Implementation of bilateral implant algorithm processing.
• Conducting simulation-based, objective, and subjective testing to validate platform accuracy.
• Evaluating source localization performance using subjective tests.

Main Results:

• The CCi-MOBILE platform successfully demonstrated bilateral implant algorithm processing.
• Subjective testing yielded a root mean square (RMS) error of ±8.66° for sound source localization.
• The platform's source localization accuracy was found to be comparable to commercial cochlear implant processors.

Conclusions:

• The CCi-MOBILE platform is a validated tool for researching bilateral cochlear implant processing.
• The platform accurately captures source localization, offering potential for improved speech intelligibility and spatial hearing for CI users.
• This research facilitates the development and testing of advanced bilateral CI strategies in realistic settings.