Reducing the Device Delay Mismatch Can Improve Sound Localization in Bimodal Cochlear Implant/Hearing-Aid Users.
Stefan Zirn, Julian Angermeier, Susan Arndt and 2 others
PMID 31018790WHAT IT FOUND
Adding a programmed delay to the cochlear implant in bimodal listeners improved sound localization accuracy by an average of 4.9 degrees.
All nine participants performed better or the same after one hour of acclimatization. This suggests synchronizing device timing can help users locate sounds more effectively.
Key findings
01Minimizing the device delay mismatch by delaying the CI signal significantly improved localization accuracy across all bimodal listeners, with a mean improvement of 4.9 degrees (12.1%).
02All nine bimodal participants either improved or maintained their localization performance when the CI delay was applied; none performed worse.
03Normal-hearing listeners could not compensate for a 7 ms unilateral delay even after one hour of training, indicating that the auditory system has limited plasticity for large timing mismatches.
STILL TO COME
How it was doneWhat they foundWhat it means for SLPs
Read the rest of this summary
You get three full summaries a month, free, and we do not ask for a card. Search, the TL;DRs and your library stay unlimited either way.
What it does not show
The study used a custom hardware delay line rather than a commercially available clinical solution, so the findings describe a potential benefit of a technology that may not yet be accessible. The sample size of nine bimodal participants is small. The delay applied was a fixed average based on the hearing aid's processing time, not a precise frequency-specific match. Acclimatization was limited to one hour, which may not reflect long-term adaptation or the full benefit of the intervention.
Declared interests
The work was funded by MED-EL Elektromedizinische Geräte Gesellschaft m.b.H., a manufacturer of cochlear implant systems.
The easy way to misread this
Do not assume that all bimodal patients will experience a large clinical benefit from delay compensation. The average improvement was 4.9 degrees, which is statistically significant but may be subtle in daily life, and individual responses varied from no change to a 9.8-degree improvement.