Rapid mechanical stimulation of inner-ear hair cells by photonic pressure
Abstract
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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Rapid mechanical stimulation of inner-ear hair cells by photonic pressureDryad Digital Repository, doi:10.5061/dryad.76hdr7sww.
Article and author information
Author details
Funding
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.
Ethics
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).
Copyright
© 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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