A Mixed-Rate Strategy on a Bilaterally-Synchronized Cochlear Implant Processor Offering the Opportunity to Provide...

Area of Science:

• Audiology
• Neuroscience
• Biomedical Engineering

Background:

• Bilateral cochlear implant (CI) users often lack access to interaural time differences (ITDs), crucial for sound localization and speech comprehension in noise.
• Current CI processors face challenges in simultaneously encoding ITDs (best at low stimulation rates) and speech information (best at high stimulation rates).

Purpose of the Study:

• To develop and evaluate a novel
• mixed-rate
• sound coding strategy for bilaterally implanted CI users.
• To assess the impact of this strategy on speech understanding and sound localization abilities.

Main Methods:

• Implemented a mixed-rate strategy using a bilaterally synchronized research processor (CCi-MOBILE).
• Encoded ITD information on some channels at low stimulation rates and speech information on other channels at high rates.
• Tested nine bilateral CI users on speech understanding and sound localization tasks.

Main Results:

• Performance in speech understanding and sound localization tasks was comparable between the new mixed-rate strategy and a control strategy.
• The study demonstrated the feasibility of the mixed-rate approach in a practical setting.

Conclusions:

• The mixed-rate sound coding strategy shows potential for improving auditory perception in bilateral CI users.
• Further discussion on the benefits, drawbacks, and guidelines for utilizing synchronized processors in CI strategy development is provided.