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Cochlear efferent feedback balances interaural sensitivity.

Keith N Darrow·Stéphane F Maison·M Charles Liberman
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Abstract

Neurons in the lateral superior olive (LSO) compute sound location based on differences in interaural intensity, coded in ascending signals from the two cochleas. Unilateral destruction of the neuronal feedback from the LSO to the cochlea, the lateral olivocochlear efferents, disrupted the normal interaural correlation in response amplitudes to sounds of equal intensity. Thus, lateral olivocochlear feedback maintains the binaural balance in neural excitability required for accurate localization of sounds in space.

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Acoustic StimulationAnalysis of VarianceAnimalsAuditory PathwaysCochleaCochlear NerveDominance, CerebralEfferent PathwaysFeedback, PsychologicalMiceNerve Fibers, UnmyelinatedOlivary NucleusSound LocalizationJournal ArticleResearch Support, N.I.H., Extramural

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Keith N Darrow, Stéphane F Maison, M Charles Liberman. 2006-11-19. Cochlear efferent feedback balances interaural sensitivity.. https://doi.org/10.1038/nn1807

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