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Rapid mechanical stimulation of inner-ear hair cells by photonic pressure

  1. Sanjeewa Abeytunge
  2. Francesco Gianoli
  3. A James Hudspeth  Is a corresponding author
  4. Andrei Kozlov  Is a corresponding author
  1. Imperial College London, United Kingdom
  2. Howard Hughes Medical Institute, The Rockefeller University, United States
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Cite this article as: eLife 2021;10:e65930 doi: 10.7554/eLife.65930


Hair cells, the receptors of the inner ear, detect sounds by transducing mechanical vibrations into electrical signals. From the top surface of each hair cell protrudes a mechanical antenna, the hair bundle, which the cell uses to detect and amplify auditory stimuli, thus sharpening frequency selectivity and providing a broad dynamic range. Current methods for mechanically stimulating hair bundles are too slow to encompass the frequency range of mammalian hearing and are plagued by inconsistencies. To overcome these challenges, we have developed a method to move individual hair bundles with photonic force. This technique uses an optical fiber whose tip is tapered to a diameter of a few micrometers and endowed with a ball lens to minimize divergence of the light beam. Here we describe the fabrication, characterization, and application of this optical system and demonstrate the rapid application of photonic force to vestibular and cochlear hair cells.

Data availability

All source data can be found on Dryad:CitationAbeytunge, Sanjeewa; Gianoli, Francesco; Hudspeth, A. James; Kozlov, Andrei S. (2021), Rapid mechanical stimulation of inner-ear hair cells by photonic pressure, Dryad, Dataset, https://doi.org/10.5061/dryad.76hdr7sww

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Article and author information

Author details

  1. Sanjeewa Abeytunge

    Bioengineering, Imperial College London, London, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
  2. Francesco Gianoli

    Bioengineering, Imperial College London, London, United Kingdom
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-4876-7978
  3. A James Hudspeth

    Laboratory of Sensory Neuroscience, Howard Hughes Medical Institute, The Rockefeller University, New York, United States
    For correspondence
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-0295-1323
  4. Andrei Kozlov

    Bioengineering, Imperial College London, London, United Kingdom
    For correspondence
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-1993-8341


Howard Hughes Medical Institute

  • A James Hudspeth

Wellcome Trust (108034/Z/15/Z)

  • Andrei Kozlov

Wellcome Trust (214234/Z/18/Z)

  • Andrei Kozlov

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.


Animal experimentation: All procedures were conducted according to the rules and regulations of the homeinstitution. At The Rockefeller University the procedures were approved by theInstitutional Animal Care and Use Committee. At Imperial College London, theprocedures were carried out in accordance with the U.K. Home Office Animals(Scientific Procedures) Act (1986).

Reviewing Editor

  1. Fred Rieke, University of Washington, United States

Publication history

  1. Received: December 18, 2020
  2. Accepted: July 2, 2021
  3. Accepted Manuscript published: July 6, 2021 (version 1)


© 2021, Abeytunge et al.

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.


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