Advances in Hearing

FRom CIHear

Message: 20
Date: Thu, 3 Feb 2005 20:17:55 -0500
From: "Robert MacPherson"
Subject: Press Release: U-M Scientists Develop First Micro-Machined
Cochlea

The University of Michigan news service, Feb. 2, 2005
-----------------


U-M scientists develop first micro-machined mechanical cochlea

ANN ARBOR, Mich.—Scientists at U-M have developed the first
micro-machined, life-sized, mechanical
cochlea, the tiny organ responsible for converting acoustic vibrations
into electrical signals for
the brain to "read" and interpret as different sounds.

Most people with hearing loss have lost the ability to translate
acoustic sound waves into
electrical signals for the brain, so developing a device capable of
simulating this function is an
important step in the effort to help at least some of the estimated 560
million people who will
experience hearing loss by this year. While the U-M system is not yet
ready for use as an implant,
the 3-centimeter device could potentially be used as part of a cochlear
implant. More immediate
applications include a low-power sensor for military or commercial
applications, said College of
Engineering associate professor Karl Grosh.

The three advantages of the mechanical cochlea built at U-M are its
life-sized dimensions, its
suitability for mass production, and its use of a unique low-power
mechanical method to do acoustic
signal processing, Grosh said. The human cochlea is a snail-shaped
organ measuring about a cubic
centimeter in the inner ear. If you unwind the spiral, it would equal
the length of the U-M
mechanical cochlea. Researchers micro-machined the device using a
technique similar to those used to
make integrated circuits, which means it can be mass produced.

The mechanical cochlea works in the same way as its biological
counterpart. In the biological
cochlea, the basilar membrane, which winds along the cochlear spiral,
is stiffer at the base and
becomes softer as it approaches the center. In the engineered cochlea
developed by Grosh and
doctoral student Robert White, a fluid-filled duct etched onto a chip
acts as the cochlear spiral.
When sound waves enter the mechanical cochlea's input membrane, a wave
is created, which travels
down the duct, interacting with a tapered micro-machined membrane,
analogous to the basilar
membrane. This process allows the device to separate different
frequency tones. In the biological
cochlea, sensory hair cells in the spiral detect the sound waves
traveling through the fluid, and
translate the sound waves into electrical signals, which the auditory
nerve carries to the brain.
The ear hears different sounds depending on where the wave vibrates in
the cochlea.

The goal is to use the mechanical cochlea as a sensitive microphone,
perhaps in tandem with a
cochlear implant, Grosh said, the same way an external microphone, a
microprocessor and an antenna
work together in present implants. Cochlear implants work by sending
signals for different
frequencies to electrodes implanted in the cochlear spiral. The
auditory nerves then transport these
signals to the brain. Researchers are adding arrays of sensors to the
mechanical cochlea, which
would make it possible to use the new device to drive the electrodes in
a cochlear implant.

Grosh and White co-authored a paper "Microengineered Hydromechanical
Cochlear Model," which appeared
in the Proceedings of the National Academy of Sciences, Feb. 1, 2005.

The work is primarily funded by the National Science Foundation and the
Office of Naval Research.

The University of Michigan College of Engineering is ranked among the
top engineering schools in the
country. Michigan Engineering boasts one of the largest research
budgets of any public university,
at $135 million for 2004. Michigan Engineering has 11 departments and
two NSF Engineering Research
Centers. Within those departments and centers, there is a special
emphasis on research in three
emerging industries: Nanotechnology and integrated microsystems;
cellular and molecular
biotechnology; and information technology. The College is seeking to
raise $110 million for capital
building projects and program support in these areas to further
research discovery. The CoE's goal
is to advance academic scholarship and market cutting edge research to
improve public heath and
well-being.

News from Overseas

The Tartan Online

Waldron to aid elderly
By Noelle Selb
nselb@radford.edu

February 01, 2005

It is easy to take for granted the resonating call of the Muse clock alerting students when they are late for class, the unmistakable whistle of the train passing through Radford at night, the voice of the waitress asking for an order. However, for many elderly in the New River Valley, these sounds are silenced.

In an attempt to reach out to the community to ease this problem and other health issues affecting older adults in the area, the Carlot Endowment recently awarded Waldron College of Health and Human Services over $12,694 to aid the lower-income adults in Southwestern Virginia.

The endowment was created in memory of the late professor of emeritus of design, Fernande Gard, by her mother Fernande Carlot Gard and her grandfather Albert Carlot, and is dispensed by the RU Foundation.

The money was apportioned to three programs that professors from Waldron College supported. These programs include Dr. Ken Cox’s “Hearing Healthcare services for the Needy Elderly in Southwest Virginia,” Dr. Mary Hope Gibson’s “Chronic Illness Clinic,” and Dr. Virginia Burgraff and Grace Shortt’s “Case Management and Assessment of Rural Elderly (CARE) Project.”

In an effort to serve the uninsured and underinsured adults over 55 years old, the CARE program will use case management to serve older adults in the Dublin, Pulaski and Radford City areas. Burgraff describes case management as an overall process where the care providers look at the patient as a whole and try to meet his or her needs, in addition to performing a functional assessment.

In her piece of the grant, Burgraff is using graduate student Sarah Gilbert, to implement the functional assessment of patients, as well as looking at other aspects of health, such as depression, sleep and eating.

“Functional assessment means I can perform activities of daily living, which include cooking, bathing, toileting. Advanced activities of daily living include going to the store to buy food, preparing my meals, using the telephone. If I can’t do these things, then are there resources in the community that can assist me?” Burgraff explained.

Gilbert, a Registered Nurse who graduated from RU in 1980 with a degree in nursing, mentioned that the types of assessments the patients will undergo will include a standard assessment, which encompasses information about their living situation, the availability of transportation, as well as the patient’s ability to perform the functions of everyday living, such as grocery shopping.

Cox’s program provides an important service to the elderly in the community yet focuses more on a physical need than a functional need. For the two and a half years since funding to provide hearing aids for the local Lion’s Club was discontinued, Cox has been trying to re-establish the grant to provide hearing aids for Southwest Virginia.

Since most insurance companies do not pay for hearing aids and others only pay a portion of the cost, many of the individuals on the waiting list to receive hearing aids have done without any sort of hearing device for over two years. The Carlot Endowment is set up to provide money to purchase hearing aids from the Starkey Hear Now Foundation, which provides assistance to those with financial need.

Cox’s “Hearing Healthcare Services for the Needy Elderly in Southwest Virginia” program will provide 20 hearing aids over the course of the next six months to a year for those who qualify based on financial need as well as who meet the age requirements.

Graduate students who participate in the audiology clinic within the RU clinics will participate in the counseling, fitting and follow-up of the eligible older adults involved in the program. They will work with audiologist Joanne Dillon, an RU graduate and a licensed audiologist and hearing aid specialist.

Cox has also submitted a large grant for the Lions of Virginia Foundation which is in the process of being reviewed. If the money is granted, Cox says that it would help a lot more people in the community.

Gibson’s “Hearing Healthcare Services for the Needy Elderly in Southwest Virginia” received $4,594 to assist primary health care services in RU Clinics for older adults. The aspiration of Gibson’s project is to prevent complications which could arise from existing health conditions and to prevent contracting new illnesses among clients unable to afford health services in other locations.

Through the Carlot Endowment, students and their professors implementing these programs can follow through to the mission statement of the RU School of Nursing and fellow departments within Waldron College, helping a generation that comprises 11 to 17 percent of the population in the NRV.