How spatial release from masking may fail to function in a highly directional auditory system
Abstract
Spatial release from masking (SRM) occurs when spatial separation between a signal and masker decreases masked thresholds. The mechanically-coupled ears of Ormia ochracea are specialized for hyperacute directional hearing, but the possible role of SRM, or whether such specializations exhibit limitations for sound source segregation, is unknown. We recorded phonotaxis to a cricket song masked by band-limited noise. With a masker, response thresholds increased and localization was diverted away from the signal and masker. Increased separation from 6° to 90° did not decrease response thresholds or improve localization accuracy, thus SRM does not operate in this range of spatial separations. Tympanal vibrations and auditory nerve responses reveal that localization errors were consistent with changes in peripheral coding of signal location and flies localized towards the ear with better signal detection. Our results demonstrate that, in a mechanically coupled auditory system, specialization for directional hearing does not contribute to source segregation.
Data availability
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Data from: How spatial release from masking may fail to function in a highly directional auditory systemAvailable at Dryad Digital Repository under a CC0 Public Domain Dedication.
Article and author information
Author details
Funding
Natural Sciences and Engineering Research Council of Canada (Discovery Grant)
- Andrew C Mason
Natural Sciences and Engineering Research Council of Canada (PGS D3)
- Norman Lee
Ontario Graduate Scholarship
- Norman Lee
Society for Integrative and Comparative Biology grants-in-aid of research
- Norman Lee
Animal Behavior Society Student Grant
- Norman Lee
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Catherine Emily Carr, University of Maryland, United States
Version history
- Received: August 17, 2016
- Accepted: April 19, 2017
- Accepted Manuscript published: April 20, 2017 (version 1)
- Accepted Manuscript updated: April 24, 2017 (version 2)
- Accepted Manuscript updated: April 25, 2017 (version 3)
- Version of Record published: May 24, 2017 (version 4)
Copyright
© 2017, Lee & Mason
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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