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Neurons in primary auditory cortex represent sound source location in a cue-invariant manner.

ABSTRACT: Auditory cortex is required for sound localisation, but how neural firing in auditory cortex underlies our perception of sound sources in space remains unclear. Specifically, whether neurons in auditory cortex represent spatial cues or an integrated representation of auditory space across cues is not known. Here, we measured the spatial receptive fields of neurons in primary auditory cortex (A1) while ferrets performed a relative localisation task. Manipulating the availability of binaural and spectral localisation cues had little impact on ferrets' performance, or on neural spatial tuning. A subpopulation of neurons encoded spatial position consistently across localisation cue type. Furthermore, neural firing pattern decoders outperformed two-channel model decoders using population activity. Together, these observations suggest that A1 encodes the location of sound sources, as opposed to spatial cue values.

SUBMITTER: Wood KC

PROVIDER: S-EPMC6616358 | biostudies-literature | 2019 Jul

REPOSITORIES: biostudies-literature

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Neurons in primary auditory cortex represent sound source location in a cue-invariant manner.

Wood Katherine C KC Town Stephen M SM Bizley Jennifer K JK

Nature communications 20190709 1

Auditory cortex is required for sound localisation, but how neural firing in auditory cortex underlies our perception of sound sources in space remains unclear. Specifically, whether neurons in auditory cortex represent spatial cues or an integrated representation of auditory space across cues is not known. Here, we measured the spatial receptive fields of neurons in primary auditory cortex (A1) while ferrets performed a relative localisation task. Manipulating the availability of binaural and s ...[more]

PMID: 31289272

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