# Capacitive Pressure/Velocity Probe for Acoustic Measurements in the Human Ear Canal

> **NIH NIH R01** · STATE UNIVERSITY OF NY,BINGHAMTON · 2022 · $321,147

## Abstract

The aim of this research is to create a miniature acoustic velocity sensor which, when combined with a
conventional miniature pressure microphone will enable accurate measurements of otoacoustic
emissions and wideband middle-ear reflectance within the human ear canal. These quantities reveal
important information about the functional status of the peripheral auditory system.
Existing methods of making acoustic measurements within the ear canal using sound pressure
microphones suffer from the strong dependence of pressure on the measurement location. This
research will enable the detection of acoustic particle velocity simultaneously with sound pressure
providing a much more repeatable and reliable measure of otoacoustic emissions than existing
methods.
Existing methods for measuring physiologically relevant sounds in the ear canal also suffer because
these sounds are often very quiet, close to the noise floors of the miniature microphones employed in
state-of-the-art systems for measuring otoacoustic emissions. The proposed effort will enable the
detection of otoacoustic emissions at levels at least 10 dB lower than currently feasible. Lowering the
measurement noise floor will reduce the averaging time necessary to extract these signals from noise
and enable the detection of much quieter otoacoustic emissions, which can be important in subjects
with hearing loss. Extending our ability to measure these important sounds in the human ear canal will
lead to new discoveries of middle and inner ear function and will provide greatly improved clinical tools
for the hearing impaired.
This research comprises an extension of a recent discovery by the investigators that nanoscale fibers can
be driven by viscous forces such that their sound-induced vibrations can be nearly identical to that of
the air in a sound field. The motion of air velocity-driven electrodes will be detected using their new
approach to capacitive sensing that is appropriate for highly compliant structures such as those used
here.
The novel acoustic velocity sensor will then be incorporated with a low-noise miniature hearing aid
microphone in a measurement device. Acoustic measurements in human ear canals obtained using this
low-noise and robust system will then be compared to those obtained using existing methods.

## Key facts

- **NIH application ID:** 10359702
- **Project number:** 5R01DC017720-04
- **Recipient organization:** STATE UNIVERSITY OF NY,BINGHAMTON
- **Principal Investigator:** RONALD N MILES
- **Activity code:** R01 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2022
- **Award amount:** $321,147
- **Award type:** 5
- **Project period:** 2019-03-02 → 2024-02-29

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10359702

## Citation

> US National Institutes of Health, RePORTER application 10359702, Capacitive Pressure/Velocity Probe for Acoustic Measurements in the Human Ear Canal (5R01DC017720-04). Retrieved via AI Analytics 2026-05-23 from https://api.ai-analytics.org/grant/nih/10359702. Licensed CC0.

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