Related Experiment Video
Updated: May 13, 2026
06:04
Systematic Hearing Performance Evaluation Process for Adolescents with Cochlear Implantation at Early Ages
Published on: March 24, 2023
471
Simulation of unilateral and bilateral cochlear implants on spatial speech-in-noise tasks
Mengchao Zhang1, Christine du Plessis1
1Audiology Department, College of Health and Life Sciences, Aston University, Birmingham, B4 7ET, United Kingdom.
The Journal of the Acoustical Society of America
|September 2, 2025
Summary
This study simulated bilateral cochlear implants (CI) and found binaural benefits in noise, but only when masking was energetic or modulated, not informational. Results differed from real CI users, highlighting the need for further research.
Area of Science:
- Auditory Neuroscience
- Speech Processing
- Hearing Technology
Background:
- Cochlear implants (CI) aim to restore hearing but often result in reduced speech understanding in noisy environments.
- Binaural hearing provides significant advantages for speech perception in noise, but these benefits are often diminished in CI users.
- Understanding the factors limiting binaural benefits in CI users is crucial for improving hearing device performance.
Purpose of the Study:
- To simulate bilateral and unilateral cochlear implant (CI) processing in normal-hearing listeners using the SPIRAL vocoder.
- To investigate the impact of different masker types (energetic, modulated, informational) and locations on spatial speech recognition.
- To evaluate the presence and extent of binaural benefits (summation, squelch) under simulated CI conditions.
Main Methods:
- 13 normal-hearing listeners participated in the study.
- A channel vocoder with dense tonal carriers (SPIRAL) simulated CI processing.
- Spatial speech-in-noise recognition was tested with varying masker types and locations (0°, +90°, -90°).
Main Results:
- Simulated bilateral CI users demonstrated binaural benefits in energetic and modulated maskers.
- Binaural benefits were not observed in the presence of language-based informational masking.
- The simulated binaural benefits did not consistently align with findings from studies on actual CI users.
Conclusions:
- The SPIRAL vocoder is a valuable tool for simulating CI processing and investigating binaural hearing.
- Binaural benefits in simulated CI users are dependent on the masker's energetic and informational components.
- Further research using this simulation approach is needed to identify specific factors influencing binaural benefits in bilateral CIs.
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