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Author Spotlight: Advancements in Cultivating Mouse Hair Cells for Auditory Research
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Hair cell and neural contributions to the cochlear summating potential
Andrew K Pappa1, Kendall A Hutson1, William C Scott1
1Department of Otolaryngology and Head and Neck Surgery, University of North Carolina at Chapel Hill , Chapel Hill, North Carolina.
Journal of Neurophysiology
|April 4, 2019
Summary
The cochlear summating potential (SP) arises from outer hair cells, inner hair cells, and the auditory nerve, each contributing differently. This explains the SP
Area of Science:
- Auditory Neuroscience
- Otoacoustic Emissions
- Cochlear Physiology
Background:
- The cochlear summating potential (SP) is an enigmatic electrophysiological response.
- Its origins and variable characteristics across frequency and intensity remain unclear.
Purpose of the Study:
- To pharmacologically isolate and characterize the contributions of different cochlear sources to the SP.
- To elucidate the complex origins of the SP in the gerbil cochlea.
Main Methods:
- Utilized pharmacological agents (furosemide, kanamycin, kainic acid) to selectively eliminate hair cells and neurons.
- Recorded electrophysiological responses from the gerbil cochlea before and after toxin application.
- Employed subtraction techniques to isolate contributions from outer hair cells (OHCs), inner hair cells (IHCs), and the auditory nerve.
Main Results:
- Outer hair cells (OHCs) contributed negatively to the SP.
- Inner hair cells (IHCs) and the auditory nerve contributed positively to the SP.
- The overall SP is a summation of these distinct, polarity- and magnitude-varying sources.
Conclusions:
- The enigmatic nature of the SP is explained by the complex summation of contributions from OHCs, IHCs, and the auditory nerve.
- A significant neural contribution to the SP was confirmed in human cochlear implant subjects, mirroring findings in gerbils.
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