Cochlear Implants
Conditions
Keywords
speech audiometry, psychophysical tuning curve, electrophysiology, auditory brainstem response
Brief summary
The goal of this study is to take into account channel interaction in the cochlear implant (CI) fitting process. Designing a fast and accurate method of measurement would help to customize the fitting procedures to patients' specificities in order to maximize speech understanding in every day conditions especially in noise.
Interventions
Subjects will be asked to repeat lists of words played by speakers in a noisy environment generated by the same speakers. A percentage of correct recognition is calculated for each list.
OTHERPsychophysical tuning curves in forward masking
Sounds of variable center frequency are used as maskers, and a tone with a fixed frequency at a fixed level is the target. What is tested here is the level of masker that just masks the target.
OTHERElectrically-evoked Auditory Brainstem Response (EABR)
Channel interaction assessment using eABRs (auditory nerve responses). The method consists of two measurements: 1) eABR measurements with stimulation by a single electrode of the cochlear implant at 70% of the dynamic range (four different electrodes are tested); 2) Measurement of a single eABR with stimulation from all four electrodes at 70% of the dynamic range. A comparison of the eABRs obtained by these two measurements, indicates the electrical and neural interactions between the electrodes.
OTHERTonal audiometry
Tonal audiometry will be performed with headphones
OTHERAuditory canal examination
Otoscopic examination of external auditory canal and eardrum
Sponsors
Hospices Civils de Lyon
Study design
Allocation
NON_RANDOMIZED
Intervention model
PARALLEL
Primary purpose
BASIC_SCIENCE
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to 60 Years
Healthy volunteers
Yes
Inclusion criteria
* Fluent in French * Able to understand written instructions * Under French public medical insurance * Normal-hearing subjects only: * Adult between 18 and 50 years old * Without a remarkable otological medical history, for example: chronic otitis, trans-tympanic tubes and / or all ear surgeries; * Clear auditory canal and normal eardrum; * Average audiometric loss under 20 decibels Hearing Level (dB HL) * Cochlear implant users only: * Adult between 18 and 60 yo * Normal middle ear * Used the cochlear implant for more than a year * Wearing a device from the company Neurelec/Oticon Medical
Exclusion criteria
* Behavioral and/or neurological disorders * Proven psychological disorder * Use of psychotropic medication * People who experience migraine attacks on a regular basis * Use of ototoxic medication * Exposed to loud noises within the last 72 hours * Included in another clinical trial that uses medication
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Percentage of syllable correctly recognized during speech audiometry test | At inclusion | Subjects will be asked to repeat lists of words played by speakers in a noisy environment generated by the same speakers. A percentage of correct recognition is calculated for each list. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Sound masking threshold | At inclusion | Measurement of channel interaction by establishing psychophysical tuning curves in forward masking. Sounds of variable center frequency are used as a masker, and a tone with a fixed frequency at a fixed level is the target. What is tested here is the level of masker that just masks the target. |
| Electrically-evoked Auditory Brainstem Response (eABR) | Up to 12 months after inclusion | Channel interaction assessment using eABRs (auditory nerve responses). The method consists of two measurements: 1) eABR measurements with stimulation by a single electrode of the cochlear implant at 70% of the dynamic range (four different electrodes are tested); 2) Measurement of a single eABR with stimulation from all four electrodes at 70% of the dynamic range. A comparison of the eABRs obtained by these two measurements, indicates the electrical and neural interactions between the electrodes. |
Countries
France
Outcome results
None listed