Jong-Hoon Nam
University of Rochester, NY·Biomedical Engineering
Hearing depends on a tiny, fragile machine inside the cochlea, the snail-shaped part of the inner ear that turns sound into nerve signals. Hearing loss affects a large share of adults, and much of it starts with damage to this machine or to the sealed fluids that bathe it.
- Fields
Biomedical Engineering
Biophysics
Neuroscience
- Topics
cochlea
inner ear
hearing loss
- Grants
- 2 known grants, through Nov 2027
What they work on
- Measure how length changes in outer hair cells deflect the stereocilia, the hair-like sensors on hair cells, using in vitro cochlear preparations where individual outer hair cells are controlled electrically, chemically and mechanically.
- Quantify the mechanical properties of the tectorial membrane and Deiters cells, the structures mechanically in series with outer hair cells, to learn how they shape force transmission through the organ of Corti.
- Determine the range of stereocilia deflection needed to saturate hair-cell mechano-transduction, the conversion of bending into electrical signal, and use these measurements to validate the Virtual Cochlea computer models.
- Test with the validated Virtual Cochlea models whether the organ of Corti must be as compliant as the outer hair cells themselves for those cells to generate power for cochlear amplification.
- Characterize in live gerbils how sound exposure and outer-hair-cell motility change the transport of an applied neurotoxin along the length of the cochlear duct.
- Characterize the peristaltic, wave-like vibrations of the organ of Corti produced by outer-hair-cell motility, using excised cochlear tissue implanted in a new microfluidic chamber.
- Build biophysical computer models that simulate drug delivery along the cochlea by integrating the live-animal transport data with the tissue-level vibration measurements.
More about the research
Two linked questions drive this research. How do outer hair cells, cells that change length to amplify faint sounds, deliver mechanical power to the tissue around them? And could that same motion help move substances, such as drugs, through inner-ear fluids? Both projects pair experiments on animal cochlear tissue with biophysical computer models.
Why it matters
About one in five U.S. adults has some degree of hearing loss, and many hereditary, age-related and noise-induced forms trace back to damaged outer hair cells or disturbed inner-ear fluids. Clarifying how outer hair cells amplify sound could explain losses of 40–60 dB. A sound-assisted way to spread drugs or genes through the cochlea could, in the longer term, support less invasive treatments for fluid-related hearing disorders without surgical openings in the skull.
Known grants
From NIH and NSF research grants. Labs often have other funding we can't see.
Closest labs
Karl Grosh
University of Michigan, MI·Biomedical Engineering
Design and fabricate a multi-resonant piezoelectric MEMS accelerometer co-designed with an application-specific integrated circuit, and reach a 5-milligram packaged implantable sound sensor using flip-chip packaging that eliminates printed circuit board mounting.
Joseph Santos-Sacchi
Yale University, CT·Biophysics
Determine the cryo-EM structure of prestin, the outer hair cell motor protein behind cochlear amplification, in the expanded state that voltage brings about, complementing the known contracted-state structure.
Su-Hua Sha
Medical University of South Carolina, SC·Neuroscience
Test whether prolonged activation of AMPKα, an energy-sensing enzyme, by CaMKK2, LKB1 or reactive oxygen species triggers outer hair cell death after noise exposure in adult mice, using virus-delivered shRNA to silence these genes.
The school
University of Rochester: 38 labs on PI Pages, $492M a year on research, 308 research doctorates a year.
Reach out
A start for your email. Fill in the brackets.