Date of Award
College of Arts & Sciences
Falls are a major source of morbidity and mortality among the growing elderly population. Better understanding of the reasons for falls could help identify those likely to fall and design effective interventions to reduce their risk. Maintaining balance requires the integration of sensory inputs from the visual, vestibular, proprioceptive, and auditory systems, but they are complicated by different arrival times to the brain. This difference presents as a measurable “perceptual lag” on the order of milliseconds and is called the point of subjective simultaneity. The brain compensates by allowing stimuli that arrive within a certain length of time, called the “temporal binding window,” to be perceived as occurring simultaneously. Previous literature has shown that older adults have wider temporal binding windows than younger people. Its duration for stimulus pairs involving visual and auditory stimuli has been shown to shorten with increasing stimulus intensity. Changing the characteristics of balance-related sensory signals could normalize the length of the temporal binding window and improve balance function. On the other hand, point of subjective simultaneity is known to be more variable across individuals. It is hypothesized that increasing the volume of the sound stimulus would decrease the duration of its temporal binding window and the length of the perceptual lag when combining with a vestibular stimulus.
Dr. Timothy Hullar
Advisor/Committee Chair's Department
Washington University School of Medicine, Otolaryngology Department
Chen, Angela M., "Auditory Intensity Effects on Audiovestibular Integration in Young Adults" (2012). Undergraduate Theses—Restricted. 31.