Vestibular Magnetism: A Noninvasive Probe of the Organ of Balance

The human balance mechanism plays an important role in the performance of Air Force personnel in flight operations. Research is needed to better understand and predict the susceptibility of individuals to flight related balance and motion disorders. Existing balance tests, based solely on the observation of reflex responses, are difficult to quantify and rely on stimuli that are usually much greater than those involved in normal function. Moreover, in many instances, they do not distinguish disorders in the central nervous system from those in the vestibular apparatus itself. Recent experiments suggest that superconducting magnetometers, or SQUIDs, can detect magnetic signals from the organ of balance. Such measurements may probe vestibular function directly, without complicating effects from the central nervous system. The magnetic signals may also provide a quantitative measure of vestibular response over the full range of stimuli. Such information is potentially useful in basic research, and may ultimately be used in the training and selection process of Air Force personnel. During Phase I, we propose to verify that the observed magnetic effects actually arise from the organ of balance. In Phase II, we will develop new instrumentation and demonstrate the potential of this new technique for application in research, clinical diagnois, and air and space flight.