Related Experiment Video
Updated: Nov 4, 2025
Cochlear Implant Surgery and Electrically-evoked Auditory Brainstem Response Recordings in C57BL/6 Mice
Published on: January 9, 2019
Using the electrically-evoked compound action potential (ECAP) interphase gap effect to select electrode stimulation
Kara C Schvartz-Leyzac1, Teresa A Zwolan2, Bryan E Pfingst3
1Kresge Hearing Research Institute, Department of Otolaryngology, Michigan Medicine, 1150 West Medical Center Drive, Ann Arbor, MI 48109-5616, United States; Hearing Rehabilitation Center, Department of Otolaryngology, Michigan Medicine, 475 W. Market Place, Building 1, Suite A, Ann Arbor, MI 48108, United States.
Selecting cochlear implant (CI) electrode sites using the interphase gap (IPG) effect improved speech recognition. Stimulating electrodes with a higher IPG effect enhanced performance, particularly in noisy conditions, suggesting a new optimization strategy for CI users.
Area of Science:
- Neuroscience
- Biomedical Engineering
- Audiology
Background:
- The interphase gap (IPG) effect in electrically evoked compound action potentials (ECAPs) correlates with spiral ganglion neuron (SGN) density in animal models.
- In cochlear implant (CI) users, ECAP IPG effect measures correlate with speech recognition performance.
Purpose of the Study:
- To investigate the efficacy of selecting CI electrode sites based on the ECAP IPG effect to enhance speech recognition.
- To compare speech recognition performance using electrode stimulation strategies based on high vs. low ECAP IPG effects.
Main Methods:
- ECAP IPG effect for peak amplitude was measured in 18 adult CI users.
- Experimental programs stimulated electrodes with highest or lowest ECAP IPG effects; a control program used all electrodes.
- Performance on sentences-in-noise and consonant recognition tasks was evaluated for each program.
Main Results:
- Speech recognition in noise was significantly better with electrodes selected for higher ECAP IPG effects compared to lower ones.
- Consonant place cue recognition showed a similar pattern, favoring higher IPG effect sites.
- Performance with optimized higher IPG effect sites was comparable to using all electrodes.
Conclusions:
- Electrode site selection based on the ECAP IPG effect can optimize CI performance, particularly for speech in noise.
- Scalar location (scala tympani vs. vestibuli) is a crucial factor to consider in ECAP-based electrode selection for CI optimization.
