Cortical adaptation to sound reverberation
Abstract
In almost every natural environment, sounds are reflected by nearby objects, producing many delayed and distorted copies of the original sound, known as reverberation. Our brains usually cope well with reverberation, allowing us to recognize sound sources regardless of their environments. In contrast, reverberation can cause severe difficulties for speech recognition algorithms and hearing-impaired people. The present study examines how the auditory system copes with reverberation. We trained a linear model to recover a rich set of natural, anechoic sounds from their simulated reverberant counterparts. The model neurons achieved this by extending the inhibitory component of their receptive filters for more reverberant spaces, and did so in a frequency-dependent manner. These predicted effects were observed in the responses of auditory cortical neurons of ferrets in the same simulated reverberant environments. Together, these results suggest that auditory cortical neurons adapt to reverberation by adjusting their filtering properties in a manner consistent with dereverberation.
Data availability
We have provided our Matlab scripts for generating our model and figures on Github: https://github.com/PhantomSpike/DeReverb.
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Cortical adaptation to sound reverberationGitHub, PhantomSpike/DeReverb.
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Cortical adaptation to sound reverberationDryad Digital Repository, doi:10.5061/dryad.1c59zw3xv.
Article and author information
Author details
Funding
Wellcome Trust (WT108369/Z/2015/Z)
- Andrew J King
Biotechnology and Biological Sciences Research Council (BB/M010929/1)
- Kerry MM Walker
Oxford University Press (Christopher Welch Scholarship)
- Aleksandar Z Ivanov
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: Animal experimentation: The animal procedures were approved by the University of Oxford Committee on Animal Care and Ethical Review and were carried out under license from the UK Home Office, in accordance with the Animals (Scientific Procedures) Act 1986 and in line with the 3Rs. Project licence PPL 30/3181 and PIL l23DD2122. All surgery was performed under general anesthesia (ketamine/medetomidine) and every effort was made to minimize suffering.
Copyright
© 2022, Ivanov et al.
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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