TY  - JOUR
U1  - Zeitschriftenartikel, wissenschaftlich - begutachtet (reviewed)
A1  - Angermeier, Julian
A1  - Hemmert, Werner
A1  - Zirn, Stefan
T1  - Sound Localization Bias and Error in Bimodal Listeners Improve Instantaneously When the Device Delay Mismatch Is Reduced
JF  - Trends in Hearing
N2  - Users of a cochlear implant (CI) in one ear, who are provided with a hearing aid (HA) in the contralateral ear, so-called bimodal listeners, are typically affected by a constant and relatively large interaural time delay offset due to differences in signal processing and differences in stimulation. For HA stimulation, the cochlear travelling wave delay is added to the processing delay, while for CI stimulation, the auditory nerve fibers are stimulated directly. In case of MED-EL CI systems in combination with different HA types, the CI stimulation precedes the acoustic HA stimulation by 3 to 10 ms. A self-designed, battery-powered, portable, and programmable delay line was applied to the CI to reduce the device delay mismatch in nine bimodal listeners. We used an A-B-B-A test design and determined if sound source localization improves when the device delay mismatch is reduced by delaying the CI stimulation by the HA processing delay (τ HA ). Results revealed that every subject in our group of nine bimodal listeners benefited from the approach. The root-mean-square error of sound localization improved significantly from 52.6° to 37.9°. The signed bias also improved significantly from 25.2° to 10.5°, with positive values indicating a bias toward the CI. Furthermore, two other delay values (τ HA –1 ms and τ HA +1 ms) were applied, and with the latter value, the signed bias was further reduced in some test subjects. We conclude that sound source localization accuracy in bimodal listeners improves instantaneously and sustainably when the device delay mismatch is reduced.
KW  - bimodal hearing
KW  - sound localization
KW  - interaural stimulation timing
KW  - cochlear implant
KW  - hearing aid
Y1  - 2021
UN  - https://nbn-resolving.org/urn:nbn:de:bsz:ofb1-opus4-48279
SN  - 2331-2165
SS  - 2331-2165
U6  - https://doi.org/10.1177/23312165211016165
DO  - https://doi.org/10.1177/23312165211016165
VL  - 25
SP  - 1
EP  - 11
PB  - SAGE Publications
ER  -