Dynamic sound field audiometry: static and dynamic spatial hearing tests in the full horizontal plane

ABSTRACTAlthough spatial hearing is of great importance in everyday life, today’s routine audiological test batteries and static test setups assess sound localization, discrimination and tracking abilities rudimentarily and thus provide only a limited interpretation of treatment outcomes regarding spatial hearing performance. To address this limitation, we designed a dynamic sound field test setup and evaluated the sound localization, discrimination and tracking performance of 12 normal-hearing subjects. During testing, participants provided feedback either through a touchpad or through eye tracking. In addition, the influence of head movement on sound-tracking performance was investigated. Our results show that tracking and discrimination performance was significantly better in the frontal azimuth than in the dorsal azimuth. Particularly good performance was observed in the backward direction across localization, discrimination and tracking tests. As expected, free head movement improved sound-tracking abilities. Furthermore, feedback via gaze detection led to larger tracking errors than feedback via the touchpad. We found statistically significant correlations between the static and dynamic tests, which favor the snapshot theory for auditory motion perception.

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Pinna-Imitating Microphone Directionality Improves Sound Localization and Discrimination in Bilateral Cochlear Implant Users

10.1101/2020.03.05.20023937 ◽

2020 ◽

Cited By ~ 1

Author(s):

Tim Fischer ◽

Christoph Schmid ◽

Martin Kompis ◽

Georgios Mantokoudis ◽

Marco Caversaccio ◽

...

Keyword(s):

Cochlear Implant ◽

Sound Localization ◽

Sound Field ◽

Spatial Hearing ◽

Sound Sources ◽

Static Tests ◽

Tracking Ability ◽

Bilateral Cochlear Implant ◽

Moving Stimulus ◽

The Subject

AbstractObjectivesTo compare the sound-source localization, discrimination and tracking performance of bilateral cochlear implant users with omnidirectional (OMNI) and pinna-imitating (PI) microphone directionality modes.DesignTwelve experienced bilateral cochlear implant users participated in the study. Their audio processors were fitted with two different programs featuring either the OMNI or PI mode. Each subject performed static and dynamic sound field spatial hearing tests in the horizontal plane. The static tests consisted of an absolute sound localization test and a minimum audible angle (MAA) test, which was measured at 8 azimuth directions. Dynamic sound tracking ability was evaluated by the subject correctly indicating the direction of a moving stimulus along two circular paths around the subject.ResultsPI mode led to statistically significant sound localization and discrimination improvements. For static sound localization, the greatest benefit was a reduction in the number of front-back confusions. The front-back confusion rate was reduced from 47% with OMNI mode to 35% with PI mode (p = 0.03). The ability to discriminate sound sources at the sides was only possible with PI mode. The MAA value for the sides decreased from a 75.5 to a 37.7-degree angle when PI mode was used (p < 0.001). Furthermore, a non-significant trend towards an improvement in the ability to track sound sources was observed for both trajectories tested (p = 0.34 and p = 0.27).ConclusionsOur results demonstrate that PI mode can lead to improved spatial hearing performance in bilateral cochlear implant users, mainly as a consequence of improved front-back discrimination with PI mode.

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Effects of head movement on front-back error in sound localization

Acoustical Science and Technology ◽

10.1250/ast.24.322 ◽

2003 ◽

Vol 24 (5) ◽

pp. 322-324 ◽

Cited By ~ 36

Author(s):

Yukio Iwaya ◽

Yôiti Suzuki ◽

Daisuke Kimura

Keyword(s):

Sound Localization ◽

Head Movement

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Amount of Frequency Compression in Bimodal Cochlear Implant Users Is a Poor Predictor for Audibility and Spatial Hearing

Journal of Speech Language and Hearing Research ◽

10.1044/2021_jslhr-20-00653 ◽

2021 ◽

pp. 1-14

Author(s):

Snandan Sharma ◽

Waldo Nogueira ◽

A. John van Opstal ◽

Josef Chalupper ◽

Lucas H. M. Mens ◽

...

Keyword(s):

Speech Recognition ◽

Cochlear Implant ◽

Sound Localization ◽

High Frequency ◽

Hearing Aid ◽

Spatial Hearing ◽

Meaningful Improvement ◽

Frequency Compression ◽

Knee Point ◽

Localization Performance

Purpose Speech understanding in noise and horizontal sound localization is poor in most cochlear implant (CI) users with a hearing aid (bimodal stimulation). This study investigated the effect of static and less-extreme adaptive frequency compression in hearing aids on spatial hearing. By means of frequency compression, we aimed to restore high-frequency audibility, and thus improve sound localization and spatial speech recognition. Method Sound-detection thresholds, sound localization, and spatial speech recognition were measured in eight bimodal CI users, with and without frequency compression. We tested two compression algorithms: a static algorithm, which compressed frequencies beyond the compression knee point (160 or 480 Hz), and an adaptive algorithm, which aimed to compress only consonants leaving vowels unaffected (adaptive knee-point frequencies from 736 to 2946 Hz). Results Compression yielded a strong audibility benefit (high-frequency thresholds improved by 40 and 24 dB for static and adaptive compression, respectively), no meaningful improvement in localization performance (errors remained > 30 deg), and spatial speech recognition across all participants. Localization biases without compression (toward the hearing-aid and implant side for low- and high-frequency sounds, respectively) disappeared or reversed with compression. The audibility benefits provided to each bimodal user partially explained any individual improvements in localization performance; shifts in bias; and, for six out of eight participants, benefits in spatial speech recognition. Conclusions We speculate that limiting factors such as a persistent hearing asymmetry and mismatch in spectral overlap prevent compression in bimodal users from improving sound localization. Therefore, the benefit in spatial release from masking by compression is likely due to a shift of attention to the ear with the better signal-to-noise ratio facilitated by compression, rather than an improved spatial selectivity. Supplemental Material https://doi.org/10.23641/asha.16869485

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Tracking Control of a Nonholonomic Mobile Robot Using Neural Network

Advances in Computational Intelligence and Robotics - Handbook of Research on Advancements in Robotics and Mechatronics ◽

10.4018/978-1-4666-7387-8.ch020 ◽

2015 ◽

pp. 631-661 ◽

Cited By ~ 2

Author(s):

Şahin Yildirim ◽

Sertaç Savaş

Keyword(s):

Neural Networks ◽

Mobile Robot ◽

Tracking Error ◽

Back Propagation ◽

Open Loop ◽

Tracking Performance ◽

Back Propagation Algorithm ◽

Tracking Errors ◽

Nonholonomic Mobile Robot ◽

Feed Forward Neural Networks

The goal of this chapter is to enable a nonholonomic mobile robot to track a specified trajectory with minimum tracking error. Towards that end, an adaptive P controller is designed whose gain parameters are tuned by using two feed-forward neural networks. Back-propagation algorithm is chosen for online learning process and posture-tracking errors are considered as error values for adjusting weights of neural networks. The tracking performance of the controller is illustrated for different trajectories with computer simulation using Matlab/Simulink. In addition, open-loop response of an experimental mobile robot is investigated for these different trajectories. Finally, the performance of the proposed controller is compared to a standard PID controller. The simulation results show that “adaptive P controller using neural networks” has superior tracking performance at adapting large disturbances for the mobile robot.

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