Interaural Frequency and Loudness Mismatch in SSD CI Users
Effects of Interaural Frequency and Loudness Mismatch on SSD-CI Performance
1 other identifier
interventional
45
1 country
1
Brief Summary
Interaural loudness and pitch mismatch in single-sided deaf cochlear implant (SSD-CI) recipients reduces binaural processing cues and contributes to performance outcomes, specifically speech understanding in noise and localization. The study aims to improve binaural cues through speech processor program modifications that reduce interaural mismatches.
Trial Health
Trial Health Score
Automated assessment based on enrollment pace, timeline, and geographic reach
participants targeted
Target at P25-P50 for not_applicable
Started Aug 2022
Typical duration for not_applicable
1 active site
Health score is calculated from publicly available data and should be used for screening purposes only.
Trial Relationships
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Study Timeline
Key milestones and dates
First Submitted
Initial submission to the registry
August 8, 2022
CompletedFirst Posted
Study publicly available on registry
August 10, 2022
CompletedStudy Start
First participant enrolled
August 12, 2022
CompletedPrimary Completion
Last participant's last visit for primary outcome
July 30, 2024
CompletedResults Posted
Study results publicly available
July 1, 2025
CompletedStudy Completion
Last participant's last visit for all outcomes
August 1, 2025
CompletedMarch 23, 2026
March 1, 2026
2 years
August 8, 2022
March 17, 2025
March 9, 2026
Conditions
Outcome Measures
Primary Outcomes (1)
Speech Understanding in Noise, Measured With the R-Space Test Environment. The R-Space Test Environment Simulates Speech Understanding in a Noisy Restaurant.
Participants speech understanding was evaluated in the R-Space test environment with two speech processor programs, an everyday or default program and a modified program. The modified program was created to reduce interaural frequency or loudness mismatch between participants' CI ear and normal hearing ear. The R-Space simulates listening in a noisy restaurant, a real-world listening situation. The score is a signal-to-noise ratio that reflects 50% speech understanding in noise. Participants are surrounded by 8 loudspeakers with restaurant noise from all 8. A sentence is presented from the front loudspeaker. Participants repeat back what they hear. The noise is adjusted adaptively. For a correct response, the noise is increased; it is decreased for an incorrect response. This provides signal-to-noise ratio (SNR) for 50% speech understanding. The average score for participants with normal hearing is -5 dB SNR. A lower number represents better performance than a higher number.
Participants were tested in the R-Space twice with each speech processor program, e.g., everyday or default program and modified program. The testing was carried out within a 2-3 month time period, and after using each program for at least 6 weeks.
Study Arms (3)
Period 1: Study 1
EXPERIMENTALCI speech processor programming in experienced cochlear implant (CI) recipients with single sided deafness. Program changes were made to decrease the interaural frequency mismatch between the CI ear and the contralateral ear.
Period 2: Study 2
EXPERIMENTALCI speech processor programming in newly implanted cochlear implant (CI) recipients with single sided deafness. Program changes were made to decrease the interaural frequency mismatch between the CI ear and the contralateral ear.
Period 3: study 3
EXPERIMENTALCI speech processor programming in experienced cochlear implant (CI) recipients with single sided deafness. Program changes were made to decrease the interaural loudness mismatch between the CI ear and the contralateral ear.
Interventions
We will modify the CI speech processor program to reduce interaural loudness mismatch between the CI ear and the contralateral ear in experienced CI recipients with SSD.
We will modify the CI speech processor program to reduce interaural frequency mismatch between the CI ear and the contralateral ear in newly implanted CI recipients with SSD.
We will modify the CI speech processor program to reduce interaural frequency mismatch between the CI ear and the contralateral ear in experienced CI recipients with SSD.
Eligibility Criteria
You may qualify if:
- Participants for the proposed study will be adults with single-sided deafness. Participants will have at least 6 months experience with their cochlear implant or will be newly implanted with the cochlear implant.
- years of age and older
- Postlingual onset of SSD
- Pure tone average (PTA) at 500, 1000, and 2000 Hz of less than or equal to 30 dB HL in the contralateral ear, known as the normal hearing ear
- Implanted with or chosen to be implanted with a Nucleus cochlear implant
- Full insertion of electrode array
Contact the study team to confirm eligibility.
Sponsors & Collaborators
- Cochlearcollaborator
- Washington University School of Medicinelead
Study Sites (1)
Washington University School of Medicine
St Louis, Missouri, 63110, United States
Limitations and Caveats
One of the limitations was the small number of SSD participants in the trial.
Results Point of Contact
- Title
- Jill B Firszt, PhD
- Organization
- Washington University School of Medicine
Study Officials
- PRINCIPAL INVESTIGATOR
Jill B Firszt, PhD
Washington University School of Medicine
Publication Agreements
- PI is Sponsor Employee
- No
- Restrictive Agreement
- No
Study Design
- Study Type
- interventional
- Phase
- not applicable
- Allocation
- NON RANDOMIZED
- Masking
- NONE
- Purpose
- TREATMENT
- Intervention Model
- SINGLE GROUP
- Sponsor Type
- OTHER
- Responsible Party
- PRINCIPAL INVESTIGATOR
- PI Title
- Professor
Study Record Dates
First Submitted
August 8, 2022
First Posted
August 10, 2022
Study Start
August 12, 2022
Primary Completion
July 30, 2024
Study Completion
August 1, 2025
Last Updated
March 23, 2026
Results First Posted
July 1, 2025
Record last verified: 2026-03