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Cochlear synaptopathy: new findings in animal and human research

  • Cristian Aedo and Enzo Aguilar EMAIL logo


In animal models, prolonged exposure (2 h) to high-level noise causes an irreparable damage to the synapses between the inner hair cells and auditory nerve fibers within the cochlea. Nevertheless, this injury does not necessarily alter the hearing threshold. Similar findings have been observed as part of typical aging in animals. This type of cochlear synaptopathy, popularly called “hidden hearing loss,” has been a significant issue in neuroscience research and clinical audiology scientists. The results obtained in different investigations are inconclusive in their diagnosis and suggest new strategies for both prognosis and treatment of cochlear synaptopathy. Here we review the major physiological findings regarding cochlear synaptopathy in animals and humans and discuss mathematical models. We also analyze the potential impact of these results on clinical practice and therapeutic options.

Corresponding author: Enzo Aguilar, Laboratorio de Audiología y Percepción Auditiva, Facultad de Medicina, Universidad de Chile, Santiago, Chile; Departamento de Tecnología Médica, Facultad de Medicina, Universidad de Chile, Santiago, 9786060, Chile, E-mail:

Funding source: Universidad de Chile

Award Identifier / Grant number: U-inicia 10/16

  1. Author contribution: All the authors have accepted responsibility for the entire content of this submitted manuscript and approved submission.CA and EA wrote the paper; EA interacted with reviewers.

  2. Research funding: Work supported by a grant of the University of Chile (UI-10/16) to EA.

  3. Conflict of interest statement: The authors declare no conflicts of interest regarding this article.


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Received: 2020-01-07
Accepted: 2020-04-25
Published Online: 2020-07-20
Published in Print: 2020-08-27

© 2020 Walter de Gruyter GmbH, Berlin/Boston

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