Physiological and behavioral assessments of an auditory pathway for processing spectral cues for sound localization

2001 ◽  
Vol 109 (5) ◽  
pp. 2407-2407
Author(s):  
Brad May
Keyword(s):  
Sound Localization ◽  
Auditory Pathway ◽  
Spectral Cues ◽  
Behavioral Assessments

Left-Right and Front-Back Spatial Hearing with Multiple Directional Microphone Configurations in Modern Hearing Aids

2014 ◽  
Vol 25 (09) ◽  
pp. 791-803 ◽  
Author(s):  
Evelyne Carette ◽  
Tim Van den Bogaert ◽  
Mark Laureyns ◽  
Jan Wouters
Keyword(s):  
Sound Localization ◽  
Hearing Aids ◽  
Hearing Aid ◽  
Performance Measure ◽  
Frequency Dependent ◽  
Binaural Cues ◽  
Directional Microphone ◽  
Spectral Cues ◽  
Localization Performance ◽  
Asymmetric Configuration

Background: Several studies have demonstrated negative effects of directional microphone configurations on left-right and front-back (FB) sound localization. New processing schemes, such as frequency-dependent directionality and front focus with wireless ear-to-ear communication in recent, commercial hearing aids may preserve the binaural cues necessary for left-right localization and may introduce useful spectral cues necessary for FB disambiguation. Purpose: In this study, two hearing aids with different processing schemes, which were both designed to preserve the ability to localize sounds in the horizontal plane (left-right and FB), were compared. Research Design: We compared horizontal (left-right and FB) sound localization performance of hearing aid users fitted with two types of behind-the-ear (BTE) devices. The first type of BTE device had four different programs that provided (1) no directionality, (2–3) symmetric frequency-dependent directionality, and (4) an asymmetric configuration. The second pair of BTE devices was evaluated in its omnidirectional setting. This setting automatically activates a soft forward-oriented directional scheme that mimics the pinna effect. Also, wireless communication between the hearing aids was present in this configuration (5). A broadband stimulus was used as a target signal. The directional hearing abilities of the listeners were also evaluated without hearing aids as a reference. Study Sample: A total of 12 listeners with moderate to severe hearing loss participated in this study. All were experienced hearing-aid users. As a reference, 11 listeners with normal hearing participated. Data Collection and Analysis: The participants were positioned in a 13-speaker array (left-right, –90°/+90°) or 7-speaker array (FB, 0–180°) and were asked to report the number of the loudspeaker located the closest to where the sound was perceived. The root mean square error was calculated for the left-right experiment, and the percentage of FB errors was used as a FB performance measure. Results were analyzed with repeated-measures analysis of variance. Results: For the left-right localization task, no significant differences could be proven between the unaided condition and both partial directional schemes and the omnidirectional scheme. The soft forward-oriented system and the asymmetric system did show a detrimental effect compared with the unaided condition. On average, localization was worst when users used the asymmetric condition. Analysis of the results of the FB experiment showed good performance, similar to unaided, with both the partial directional systems and the asymmetric configuration. Significantly worse performance was found with the omnidirectional and the omnidirectional soft forward-oriented BTE systems compared with the other hearing-aid systems. Conclusions: Bilaterally fitted partial directional systems preserve (part of) the binaural cues necessary for left-right localization and introduce, preserve, or enhance useful spectral cues that allow FB disambiguation. Omnidirectional systems, although good for left-right localization, do not provide the user with enough spectral information for an optimal FB localization performance.

The contribution of spectral cues to human sound localization

1999 ◽  
Vol 105 (2) ◽  
pp. 1036-1036 ◽  
Author(s):  
Erno H. Langendijk ◽  
Adelbert W. Bronkhorst
Keyword(s):  
Sound Localization ◽  
Spectral Cues

scholarly journals Prediction of Human's Ability in Sound Localization Based on the Statistical Properties of Spike Trains along the Brainstem Auditory Pathway

2014 ◽  
Vol 2014 ◽  
pp. 1-11
Author(s):  
Ram Krips ◽  
Miriam Furst
Keyword(s):  
Time Delay ◽  
Lower Bounds ◽  
Sound Localization ◽  
Human Performance ◽  
Acoustic Stimulus ◽  
Auditory Pathway ◽  
Superior Olivary Complex ◽  
Optimal Estimator ◽  
Interaural Time Delay ◽  
Interaural Level Differences

The minimum audible angle test which is commonly used for evaluating human localization ability depends on interaural time delay, interaural level differences, and spectral information about the acoustic stimulus. These physical properties are estimated at different stages along the brainstem auditory pathway. The interaural time delay is ambiguous at certain frequencies, thus confusion arises as to the source of these frequencies. It is assumed that in a typical minimum audible angle experiment, the brain acts as an unbiased optimal estimator and thus the human performance can be obtained by deriving optimal lower bounds. Two types of lower bounds are tested: the Cramer-Rao and the Barankin. The Cramer-Rao bound only takes into account the approximation of the true direction of the stimulus; the Barankin bound considers other possible directions that arise from the ambiguous phase information. These lower bounds are derived at the output of the auditory nerve and of the superior olivary complex where binaural cues are estimated. An agreement between human experimental data was obtained only when the superior olivary complex was considered and the Barankin lower bound was used. This result suggests that sound localization is estimated by the auditory nuclei using ambiguous binaural information.

Contribution of spectral cues to human sound localization

2002 ◽  
Vol 112 (4) ◽  
pp. 1583-1596 ◽  
Author(s):  
Erno H. A. Langendijk ◽  
Adelbert W. Bronkhorst
Keyword(s):  
Sound Localization ◽  
Spectral Cues

Spectral Cues for Robust Sound Localization with Pinnae

2006 ◽  
Author(s):  
Tomoko Shimoda ◽  
Toru Nakashima ◽  
Makoto Kumon ◽  
Ryuichi Kohzawa ◽  
Ikuro Mizumoto ◽  
...  
Keyword(s):  
Sound Localization ◽  
Spectral Cues

scholarly journals Object localization using a biosonar beam: how opening your mouth improves localization

2015 ◽  
Vol 2 (8) ◽  
pp. 150225 ◽  
Author(s):  
G. Arditi ◽  
A. J. Weiss ◽  
Y. Yovel
Keyword(s):  
Sound Localization ◽  
Sound Source ◽  
Spatial Information ◽  
Signal To Noise Ratio ◽  
Object Localization ◽  
Signal Design ◽  
Sound Beam ◽  
Spectral Cues ◽  
Passive Hearing ◽  
Echolocation Signal

Determining the location of a sound source is crucial for survival. Both predators and prey usually produce sound while moving, revealing valuable information about their presence and location. Animals have thus evolved morphological and neural adaptations allowing precise sound localization. Mammals rely on the temporal and amplitude differences between the sound signals arriving at their two ears, as well as on the spectral cues available in the signal arriving at a single ear to localize a sound source. Most mammals rely on passive hearing and are thus limited by the acoustic characteristics of the emitted sound. Echolocating bats emit sound to perceive their environment. They can, therefore, affect the frequency spectrum of the echoes they must localize. The biosonar sound beam of a bat is directional, spreading different frequencies into different directions. Here, we analyse mathematically the spatial information that is provided by the beam and could be used to improve sound localization. We hypothesize how bats could improve sound localization by altering their echolocation signal design or by increasing their mouth gape (the size of the sound emitter) as they, indeed, do in nature. Finally, we also reveal a trade-off according to which increasing the echolocation signal's frequency improves the accuracy of sound localization but might result in undesired large localization errors under low signal-to-noise ratio conditions.

Sign in / Sign up

Export Citation Format

Share Document