Related Experiment Video
Updated: Sep 25, 2025
07:00
Electrically Evoked Stapedius Reflex Measurements in Cochlear Implantation and Its Application in the Postoperative Fitting Process
Published on: June 21, 2024
924
Electrically evoked auditory cortical responses elicited from individually fitted stimulation parameters in cochlear
María A Callejón-Leblic1,2, María M Barrios-Romero3, Alejandra Kontides4
1Department of Otolaryngology, Head and Neck Surgery, Virgen Macarena University Hospital, Seville, Spain.
International Journal of Audiology
|April 28, 2022
Summary
Electrically evoked auditory cortical responses (eACR) can be reliably elicited in cochlear implant (CI) users using direct intracochlear stimulation. Apical stimulation yielded the highest amplitudes, with the N1 potential being a consistent marker for auditory processing.
Area of Science:
- Neuroscience
- Audiology
- Biomedical Engineering
Background:
- Cochlear implants (CI) restore hearing by electrically stimulating the auditory nerve.
- Understanding electrically evoked auditory cortical responses (eACR) provides insights into central auditory processing in CI users.
- Individualized stimulation parameters are crucial for optimizing CI performance.
Purpose of the Study:
- To investigate electrically evoked auditory cortical responses (eACR) using individually fitted stimulation parameters in cochlear implant (CI) users.
- To evaluate the feasibility and characteristics of eACR elicited via direct intracochlear electrode stimulation.
- To identify which stimulation regions and parameters yield the most robust cortical responses.
Main Methods:
- Developed an eACR setup utilizing individually determined CI fitting parameters.
- Stimulated apical, medial, and basal electrodes with a 50-ms alternating biphasic pulse train.
- Recorded auditory cortical potentials (N1-P2 complex) in 14 adult CI users.
Main Results:
- eACR was successfully elicited in 71% of CI users via direct intracochlear stimulation.
- Apical and medial electrode stimulation resulted in higher N1-P2 amplitudes compared to basal stimulation.
- Earlier N1 latencies were observed in users with lower comfortable loudness levels and shorter phase durations during apical stimulation.
Conclusions:
- Direct intracochlear stimulation with individual CI parameters can effectively elicit eACR.
- The N1 cortical potential is a consistent and reliable indicator for assessing eACR and central auditory processing in CI users.
- Apical stimulation appears most effective for evoking strong cortical responses, suggesting its importance in CI programming.
