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Updated: Jul 6, 2026
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Systematic Hearing Performance Evaluation Process for Adolescents with Cochlear Implantation at Early Ages
Published on: March 24, 2023
Effect of frequency boundary assignment on speech recognition with the Nucleus 24 ACE speech coding strategy
Marios S Fourakis1, John W Hawks, Laura K Holden
1Department of Communicative Disorders, University of Wisconsin-Madison, 1975 Willow Drive, Madison, WI 53706, USA. fourakis@wisc.edu
Journal of the American Academy of Audiology
|March 11, 2008
Summary
Optimizing cochlear implant (CI) frequency maps can improve speech perception. This study found a specific electrode allocation strategy, with more channels below 3000 Hz, enhances CI performance.
Area of Science:
- Audiology
- Neuroscience
- Biomedical Engineering
Background:
- Cochlear implant (CI) frequency allocation impacts speech perception in adults.
- Previous technological limits restricted exploring new frequency assignments.
- The SPEAR3 research processor enables novel frequency assignment investigations.
Purpose of the Study:
- To evaluate four distinct frequency assignments for CI analysis channels.
- To determine optimal electrode allocation for improved speech perception.
- To assess participant accommodation to CI frequency map changes.
Main Methods:
- Four different frequency assignments were tested using various speech stimuli.
- Adult CI recipients participated in the study.
- Participant speech perception performance was measured across assignments.
Main Results:
- No single frequency assignment was significantly preferred by all participants.
- Participants generally accommodated to changes in frequency assignments.
- Optimal performance was linked to allocating 7-8 electrodes below 1000 Hz, most remaining between 1100-3000 Hz, and 1-3 electrodes above 3 kHz.
Conclusions:
- Frequency assignment flexibility in cochlear implants can enhance speech perception.
- A strategy emphasizing lower and mid-frequency representation is beneficial.
- Clinical availability of flexible frequency assignments is recommended for CI users.
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