Vestibular Prosthetics: A Series of Multi-Species Investigations
Professor Dan Merfield1
Director of Jenks Vestibular Physiology Laboratory,
Mass. Eye and Ear Infirmary, Boston MA,
Associate Professor of Otology and Laryngology,
Harvard Medical School,
243 Charles Street, Boston MA
Disorders of the peripheral vestibular system are relatively common and often result in severely impaired mobility, blurred vision and debilitating attacks of vertigo and motion sickness. Presently, little can be done to resolve these symptoms when they are chronically present. While data are limited, prevalence of profound vestibular problems appears about the same as profound hearing loss. Early research in the area of vestibular neuroprosthetics, alongside the success of the cochlear implant, provides hope that providing motion cues via electrical stimulation may eventually help some patients suffering severe vestibular impairment. Conceptually, vestibular prostheses are similar to cochlear implants and consist of 4 principal elements: a power source, motion sensors, a microcontroller, and an electrode. We have developed and tested a vestibular prosthesis that senses yaw angular head velocity and uses this information to modulate the rate of current pulses applied to the vestibular nerve via an electrode chronically. This device has been tested in three species.
Daniel M. Merfeld received a Bachelors of Science in Mechanical Engineering (B.S.M.E.) from the University of Wisconsin – Madison in 1982. He then earned a Masters of Science in Engineering (M.S.E.) from Princeton University in 1985 and a Ph.D. from the Massachusetts Institute of Technology (MIT), Cambridge MA, in 1990. Shortly after his graduation, he joined the Research Staff at MIT and directed the vestibular research activities on two Spacelab Life Sciences (SLS) missions – SLS-1 and SLS-2; he was the Acting PI for the international team performing vestibular investigations on the SLS-2 mission. In 1995, he was named the Whitaker Young Investigator by the Biomedical Engineering Society and began working as a Scientist at the Neurological Sciences Institute in Portland OR. In 1999, he joined the Harvard Medical School faculty as an Associate Professor of Otology and Laryngology and founded the Jenks Vestibular Physiology Laboratory at the Massachusetts Eye and Ear Infirmary, which he now directs.