How spatial release from masking may fail to function in a highly directional auditory system

eLife

Andrew C Mason¹  Norman Lee¹ 

[1] Department of Biological Sciences, Integrative Behaviour and Neuroscience Group, University of Toronto Scarborough, Toronto, Canada;

关键词: Ormia ochracea;    cocktail-party-problem;    sound localization;    mechanically coupled pressure receiver;    song recognition;    spatial release from masking;   

DOI  :  10.7554/eLife.20731

来源: DOAJ

【 摘 要 】

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.

【 授权许可】

Unknown