Mammalian behavior and physiology converge to confirm sharper cochlear tuning in humans

Sumner, Christian J.; Wells, Toby; Bergevin, Christopher; Sollini, Joseph; Kreft, Heather; Palmer, Alan; Oxenham, Andrew; Shera, Christopher

Abstract

© 2018 National Academy of Sciences. All rights reserved. Frequency analysis of sound by the cochlea is the most fundamental property of the auditory system. Despite its importance, the resolution of this frequency analysis in humans remains controversial. The controversy persists because the methods used to estimate tuning in humans are indirect and have not all been independently validated in other species. Some data suggest that human cochlear tuning is considerably sharper than that of laboratory animals, while others suggest little or no difference between species. We show here in a single species (ferret) that behavioral estimates of tuning bandwidths obtained using perceptual masking methods, and objective estimates obtained using otoacoustic emissions, both also employed in humans, agree closely with direct physiological measurements from single auditory-nerve fibers. Combined with human behavioral data, this outcome indicates that the frequency analysis performed by the human cochlea is of significantly higher resolution than found in common laboratory animals. This finding raises important questions about the evolutionary origins of human cochlear tuning, its role in the emergence of speech communication, and the mechanisms underlying our ability to separate and process natural sounds in complex acoustic environments.

Citation

Sumner, C. J., Wells, T., Bergevin, C., Sollini, J., Kreft, H., Palmer, A., …Shera, C. (2018). Mammalian behavior and physiology converge to confirm sharper cochlear tuning in humans. Proceedings of the National Academy of Sciences, 115(44), 11322-11326. https://doi.org/10.1073/pnas.1810766115

• Journal Article Type: Article
• Acceptance Date: Sep 17, 2018
• Online Publication Date: Oct 15, 2018
• Publication Date: Oct 30, 2018
• Deposit Date: Oct 24, 2018
• Publicly Available Date: Oct 24, 2018
• Journal: Proceedings of the National Academy of Sciences
• Print ISSN: 0027-8424
• Electronic ISSN: 1091-6490
• Publisher: National Academy of Sciences
• Peer Reviewed: Peer Reviewed
• Volume: 115
• Issue: 44
• Pages: 11322-11326
• DOI: https://doi.org/10.1073/pnas.1810766115
• Keywords: Multidisciplinary
• Public URL: https://nottingham-repository.worktribe.com/output/1184573
• Publisher URL: http://www.pnas.org/content/early/2018/10/11/1810766115
• Contract Date: Oct 24, 2018