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How the auditory system encodes speech sounds is not well understood, and animal models have a lot to offer in investigating such questions. This study evaluated the representations of a variety of natural and synthetic sounds in both ferrets and humans, and reported that humans differed from ferrets in the manner in which speech and music were represented, despite controlling for the spectrotemporal content of the sounds. This work makes an important contribution to our understanding of how the coding of such sounds differs across species.
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Distinct higher-order representations of natural sounds in human and ferret auditory cortex
Little is known about how neural representations of natural sounds differ across species. For example, speech and music play a unique role in human hearing, yet it is unclear how auditory representations of speech and music differ between humans and other animals. Using functional ultrasound imaging, we measured responses in ferrets to a set of natural and spectrotemporally matched synthetic sounds previously tested in humans. Ferrets showed similar lower-level frequency and modulation tuning to that observed in humans. But while humans showed substantially larger responses to natural vs. synthetic speech and music in non-primary regions, ferret responses to natural and synthetic sounds were closely matched throughout primary and non-primary auditory cortex, even when tested with ferret vocalizations. This finding reveals that auditory representations in humans and ferrets diverge sharply at late stages of cortical processing, potentially driven by higher-order processing demands in speech and music.
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- Award ID(s):
- 2020624
- PAR ID:
- 10376895
- Date Published:
- Journal Name:
- eLife
- Volume:
- 10
- ISSN:
- 2050-084X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.7554/eLife.65566
