scholarly journals Interaural Level Difference Cues Determine Sound Source Localization by Single-Sided Deaf Patients Fit with a Cochlear Implant

2015 ◽  
Vol 20 (3) ◽  
pp. 183-188 ◽  
Author(s):  
Michael F. Dorman ◽  
Daniel Zeitler ◽  
Sarah J. Cook ◽  
Louise Loiselle ◽  
William A. Yost ◽  
...  
Keyword(s):  
Cochlear Implant ◽  
Source Localization ◽  
Sound Source ◽  
Low Frequency ◽  
Normal Hearing ◽  
Sound Source Localization ◽  
Interaural Level Difference ◽  
Relative Localization ◽  
Normal Limits ◽  
Single Sided Deafness

In this report, we used filtered noise bands to constrain listeners' access to interaural level differences (ILDs) and interaural time differences (ITDs) in a sound source localization task. The samples of interest were listeners with single-sided deafness (SSD) who had been fit with a cochlear implant in the deafened ear (SSD-CI). The comparison samples included listeners with normal hearing and bimodal hearing, i.e. with a cochlear implant in 1 ear and low-frequency acoustic hearing in the other ear. The results indicated that (i) sound source localization was better in the SSD-CI condition than in the SSD condition, (ii) SSD-CI patients rely on ILD cues for sound source localization, (iii) SSD-CI patients show functional localization abilities within 1-3 months after device activation and (iv) SSD-CI patients show better sound source localization than bimodal CI patients but, on average, poorer localization than normal-hearing listeners. One SSD-CI patient showed a level of localization within normal limits. We provide an account for the relative localization abilities of the groups by reference to the differences in access to ILD cues.

scholarly journals Sound Source Localization by Normal-Hearing Listeners, Hearing-Impaired Listeners and Cochlear Implant Listeners

2016 ◽  
Vol 21 (3) ◽  
pp. 127-131 ◽  
Author(s):  
Michael F. Dorman ◽  
Louise H. Loiselle ◽  
Sarah J. Cook ◽  
William A. Yost ◽  
René H. Gifford
Keyword(s):  
Cochlear Implant ◽  
Source Localization ◽  
Hearing Aids ◽  
Sound Source ◽  
Hearing Preservation ◽  
Normal Hearing ◽  
Hearing Impaired ◽  
Sound Source Localization ◽  
Localization Accuracy ◽  
Rms Error

Objective: Our primary aim was to determine whether listeners in the following patient groups achieve localization accuracy within the 95th percentile of accuracy shown by younger or older normal-hearing (NH) listeners: (1) hearing impaired with bilateral hearing aids, (2) bimodal cochlear implant (CI), (3) bilateral CI, (4) hearing preservation CI, (5) single-sided deaf CI and (6) combined bilateral CI and bilateral hearing preservation. Design: The listeners included 57 young NH listeners, 12 older NH listeners, 17 listeners fit with hearing aids, 8 bimodal CI listeners, 32 bilateral CI listeners, 8 hearing preservation CI listeners, 13 single-sided deaf CI listeners and 3 listeners with bilateral CIs and bilateral hearing preservation. Sound source localization was assessed in a sound-deadened room with 13 loudspeakers arrayed in a 180-degree arc. Results: The root mean square (rms) error for the NH listeners was 6 degrees. The 95th percentile was 11 degrees. Nine of 16 listeners with bilateral hearing aids achieved scores within the 95th percentile of normal. Only 1 of 64 CI patients achieved a score within that range. Bimodal CI listeners scored at a level near chance, as did the listeners with a single CI or a single NH ear. Listeners with (1) bilateral CIs, (2) hearing preservation CIs, (3) single-sided deaf CIs and (4) both bilateral CIs and bilateral hearing preservation, all showed rms error scores within a similar range (mean scores between 20 and 30 degrees of error). Conclusion: Modern CIs do not restore a normal level of sound source localization for CI listeners with access to sound information from two ears.

scholarly journals Sound source localization of filtered noises by listeners with normal hearing: A statistical analysis

2013 ◽  
Vol 133 (5) ◽  
pp. 2876-2882 ◽  
Author(s):  
William A. Yost ◽  
Louise Loiselle ◽  
Michael Dorman ◽  
Jason Burns ◽  
Christopher A. Brown
Keyword(s):  
Statistical Analysis ◽  
Source Localization ◽  
Sound Source ◽  
Normal Hearing ◽  
Sound Source Localization

scholarly journals Sound Localization in Single-Sided Deaf Participants Provided With a Cochlear Implant

2021 ◽  
Vol 12 ◽  
Author(s):  
Alexandra Annemarie Ludwig ◽  
Sylvia Meuret ◽  
Rolf-Dieter Battmer ◽  
Marc Schönwiesner ◽  
Michael Fuchs ◽  
...  
Keyword(s):  
Cochlear Implant ◽  
Sound Localization ◽  
High Frequency ◽  
Real Life ◽  
Low Frequency ◽  
Normal Hearing ◽  
Frequency Noise ◽  
Speech Understanding ◽  
Speech Understanding In Noise ◽  
Single Sided Deafness

Spatial hearing is crucial in real life but deteriorates in participants with severe sensorineural hearing loss or single-sided deafness. This ability can potentially be improved with a unilateral cochlear implant (CI). The present study investigated measures of sound localization in participants with single-sided deafness provided with a CI. Sound localization was measured separately at eight loudspeaker positions (4°, 30°, 60°, and 90°) on the CI side and on the normal-hearing side. Low- and high-frequency noise bursts were used in the tests to investigate possible differences in the processing of interaural time and level differences. Data were compared to normal-hearing adults aged between 20 and 83. In addition, the benefit of the CI in speech understanding in noise was compared to the localization ability. Fifteen out of 18 participants were able to localize signals on the CI side and on the normal-hearing side, although performance was highly variable across participants. Three participants always pointed to the normal-hearing side, irrespective of the location of the signal. The comparison with control data showed that participants had particular difficulties localizing sounds at frontal locations and on the CI side. In contrast to most previous results, participants were able to localize low-frequency signals, although they localized high-frequency signals more accurately. Speech understanding in noise was better with the CI compared to testing without CI, but only at a position where the CI also improved sound localization. Our data suggest that a CI can, to a large extent, restore localization in participants with single-sided deafness. Difficulties may remain at frontal locations and on the CI side. However, speech understanding in noise improves when wearing the CI. The treatment with a CI in these participants might provide real-world benefits, such as improved orientation in traffic and speech understanding in difficult listening situations.

scholarly journals Sound Source Localization by Hearing Preservation Patients with and without Symmetrical Low-Frequency Acoustic Hearing

2015 ◽  
Vol 20 (3) ◽  
pp. 166-171 ◽  
Author(s):  
Louise H. Loiselle ◽  
Michael F. Dorman ◽  
William A. Yost ◽  
René H. Gifford
Keyword(s):  
Source Localization ◽  
Sound Source ◽  
Low Frequency ◽  
Hearing Preservation ◽  
Sound Source Localization ◽  
Localization Accuracy ◽  
Acoustic Hearing ◽  
Low Pass ◽  
Contralateral Ear ◽  
High Pass

The aim of this article was to study sound source localization by cochlear implant (CI) listeners with low-frequency (LF) acoustic hearing in both the operated ear and in the contralateral ear. Eight CI listeners had symmetrical LF acoustic hearing and 4 had asymmetrical LF acoustic hearing. The effects of two variables were assessed: (i) the symmetry of the LF thresholds in the two ears and (ii) the presence/absence of bilateral acoustic amplification. Stimuli consisted of low-pass, high-pass, and wideband noise bursts presented in the frontal horizontal plane. Localization accuracy was 23° of error for the symmetrical listeners and 76° of error for the asymmetrical listeners. The presence of a unilateral CI used in conjunction with bilateral LF acoustic hearing does not impair sound source localization accuracy, but amplification for acoustic hearing can be detrimental to sound source localization accuracy.

scholarly journals Effects of Head Movements on Sound-Source Localization in Single-Sided Deaf Patients With Their Cochlear Implant On Versus Off

Ear & Hearing ◽  
2020 ◽  
Vol 41 (6) ◽  
pp. 1660-1674
Author(s):  
M. Torben Pastore ◽  
Sarah J. Natale ◽  
Colton Clayton ◽  
Michael F. Dorman ◽  
William A. Yost ◽  
...  
Keyword(s):  
Cochlear Implant ◽  
Source Localization ◽  
Sound Source ◽  
Head Movements ◽  
Sound Source Localization

Sound source localization from tactile aids for unilateral cochlear implant users

2013 ◽  
Vol 134 (5) ◽  
pp. 4062-4062 ◽  
Author(s):  
Xuan Zhong ◽  
Shuai Wang ◽  
Michael Dorman ◽  
William Yost
Keyword(s):  
Cochlear Implant ◽  
Source Localization ◽  
Sound Source ◽  
Sound Source Localization ◽  
Tactile Aids

scholarly journals Reducing interaural tonotopic mismatch preserves binaural unmasking in cochlear implant simulations of single-sided deafness

2020 ◽  
Author(s):  
Elad Sagi ◽  
Mahan Azadpour ◽  
Jonathan Neukam ◽  
Nicole Hope Capach ◽  
Mario A. Svirsky
Keyword(s):  
Cochlear Implant ◽  
Low Frequency ◽  
Spatial Separation ◽  
Binaural Hearing ◽  
Normal Hearing ◽  
Input Frequency ◽  
Frequency Range ◽  
Speech Processor ◽  
Frequency Information ◽  
Single Sided Deafness

Binaural unmasking, a key feature of normal binaural hearing, refers to the improved intelligibility of masked speech by adding masking noise that facilities perceived spatial separation of target and masker. A question particularly relevant for cochlear implant users with single-sided deafness (SSD-CI) is whether binaural unmasking can still be achieved if the additional masking is distorted. Adding the CI restores some aspects of binaural hearing to these listeners, although binaural unmasking remains limited. Notably, these listeners may experience a mismatch between the frequency information perceived through the CI and that perceived by their normal hearing ear. Employing acoustic simulations of SSD-CI with normal hearing listeners, the present study confirms a previous simulation study that binaural unmasking is severely limited when interaural frequency mismatch between the input frequency range and simulated place of stimulation exceeds 1-2 mm. The present study also shows that binaural unmasking is largely retained when the input frequency range is adjusted to match simulated place of stimulation, even at the expense of removing low-frequency information. This result bears implication for the mechanisms driving the type of binaural unmasking of the present study, as well as for mapping the frequency range of the CI speech processor in SSD-CI users.

scholarly journals Interaural Level Differences and Sound Source Localization for Bilateral Cochlear Implant Patients

2014 ◽  
Vol 35 (6) ◽  
pp. 633-640 ◽  
Author(s):  
Michael F. Dorman ◽  
Louise Loiselle ◽  
Josh Stohl ◽  
William A. Yost ◽  
Anthony Spahr ◽  
...  
Keyword(s):  
Cochlear Implant ◽  
Source Localization ◽  
Sound Source ◽  
Sound Source Localization ◽  
Bilateral Cochlear Implant ◽  
Interaural Level Differences
Sign in / Sign up

Export Citation Format

Share Document