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Effects of Source-to-listener Distance and Masking on Perception of Cochlear Implant Processed Speech in Reverberant Rooms

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Journal J Acoust Soc Am
Date 2009 Nov 10
PMID 19894835
Citations 8
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Abstract

Two experiments examined the effects of source-to-listener distance (SLD) on sentence recognition in simulations of cochlear implant usage in noisy, reverberant rooms. Experiment 1 tested sentence recognition for three locations in the reverberant field of a small classroom (volume=79.2 m(3)). Subjects listened to sentences mixed with speech-spectrum noise that were processed with simulated reverberation followed by either vocoding (6, 12, or 24 spectral channels) or no further processing. Results indicated that changes in SLD within a small room produced only minor changes in recognition performance, a finding likely related to the listener remaining in the reverberant field. Experiment 2 tested sentence recognition for a simulated six-channel implant in a larger classroom (volume=175.9 m(3)) with varying levels of reverberation that could place the three listening locations in either the direct or reverberant field of the room. Results indicated that reducing SLD did improve performance, particularly when direct sound dominated the signal, but did not completely eliminate the effects of reverberation. Scores for both experiments were predicted accurately from speech transmission index values that modeled the effects of SLD, reverberation, and noise in terms of their effects on modulations of the speech envelope. Such models may prove to be a useful predictive tool for evaluating the quality of listening environments for cochlear implant users.

Citing Articles

Impact of Reverberation on Speech Perception in Noise in Bimodal/Bilateral Cochlear Implant Users with and without Residual Hearing.

Konig C, Baumann U, Stover T, Weissgerber T J Clin Med. 2024; 13(17).

PMID: 39274482 PMC: 11396047. DOI: 10.3390/jcm13175269.


Speech Intelligibility and Spatial Release From Masking Improvements Using Spatial Noise Reduction Algorithms in Bimodal Cochlear Implant Users.

Zedan A, Jurgens T, Williges B, Kollmeier B, Wiebe K, Galindo J Trends Hear. 2021; 25:23312165211005931.

PMID: 33926327 PMC: 8113364. DOI: 10.1177/23312165211005931.


Evaluation of a spectral subtraction strategy to suppress reverberant energy in cochlear implant devices.

Kokkinakis K, Runge C, Tahmina Q, Hu Y J Acoust Soc Am. 2015; 138(1):115-24.

PMID: 26233012 PMC: 5392068. DOI: 10.1121/1.4922331.


Use of amplitude modulation cues recovered from frequency modulation for cochlear implant users when original speech cues are severely degraded.

Won J, Shim H, Lorenzi C, Rubinstein J J Assoc Res Otolaryngol. 2014; 15(3):423-39.

PMID: 24532186 PMC: 4010597. DOI: 10.1007/s10162-014-0444-1.


Reverberation suppression in cochlear implants using a blind channel-selection strategy.

Hazrati O, Loizou P J Acoust Soc Am. 2013; 133(6):4188-96.

PMID: 23742370 PMC: 3689789. DOI: 10.1121/1.4804313.


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