Caversaccio, M. | bioRxiv Science

bioRxiv2020

A Front-Back Confusion Metric in Horizontal Sound Localization: The FBC Score

In sound localization experiments, currently used metrics for front-back confusion (FBC) analysis weight the occurring FBCs equally, regardless of their deviation from the cone of confusion. To overcome this limitation, we introduce the FBC Score. A sound localization experiment in the horizontal plane with 12 bilaterally implanted cochlear implants (CI) users and 12 normal hearing subjects was performed to validate the method with real clinical data. The overall FBC Rate of the CI users was twice as high as the FBC Score. For the control group, the FBC Rate was 4 times higher than the FBC Score. The results indicate that the FBC Rate is inflated by FBCs that show a considerable deviation from the corresponding value on the cone of confusion.

neuroscience↗

bioRxiv2019

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

Although spatial hearing is of great importance in everyday life, todays 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.

bioengineering↗