Bilateral EABR stimulating mode testing bilateral CI patients refecting binaural integration:a preliminary study

Area of Science:

• Neuroscience
• Audiology
• Biomedical Engineering

Background:

• Bilateral cochlear implantation (CI) aims to improve hearing in both ears.
• Assessing binaural integration is crucial for understanding CI efficacy.
• Electrically evoked auditory brainstem response (EABR) is a tool to evaluate auditory pathway function.

Purpose of the Study:

• To introduce and validate a new EABR stimulation mode for analyzing binaural integration.
• To reflect cochlear function in individuals with bilateral cochlear implants.
• To correlate objective EABR measures with subjective hearing outcomes.

Main Methods:

• EABR was measured with contralateral processors closed (monaural) and then open (binaural).
• Objective measures included eV latencies and amplitudes.
• Subjective assessments used the Speech, Spatial, and Qualities of Hearing Scale (SSQ), Categories of Auditory Performance (CAP), and Speech Intelligibility Rating (SIR).
• Fifteen subjects with bilateral CI participated.

Main Results:

• The new EABR mode yielded good quality measurements for all participants.
• Binaural stimulation (both processors open) significantly reduced eV latency and increased eV amplitude compared to monaural stimulation.
• Objective EABR results showed strong consistency with subjective speech perception and auditory ability scores (SSQ, CAP, SIR).

Conclusions:

• EABR accurately reflects auditory pathway maturation and development post-CI.
• Objective EABR findings align with subjective speech and hearing performance.
• Bilateral CI enhances binaural integration and auditory brainstem plasticity.