Doctor of Philosophy (PhD)


Communication Sciences and Disorders

Document Type



The overall purpose of this study was to evaluate the effects of unilateral vestibular disorders and aging on functional performances of activities of daily living and vestibular rehabilitation exercises by examining the correlations among actual and perceived functional measures, the kinematic measurement differences among young healthy adults, older healthy adults, and older adults with unilateral vestibular deficits, and the correlations between kinematic and functional measures. Perceived and actual functional abilities and kinematic variables were compared for young controls, older healthy controls, and patients with unilateral vestibular hypofunction with no previous vestibular rehabilitation. In older adults, better strength, balance, coordination, and endurance during activities of daily living were associated with better perceived ambulation and reduction in perceived functional handicap. Older adults had difficulties stabilizing their heads relative to the environment during eye exercises and moved their heads more when the exercise required head stabilization relative to the body, probably due to alterations in performance of the exercises. Patients, who were also older adults, were able to suppress some of these movements, likely to prevent dizziness. Both older groups often reduced their head movements and/or moved differently from the young when movements were self-selected and not externally driven by a visual cue. When patients were forced to make greater horizontal head movements with intermittent gaze stabilization, they also made greater head movements orthogonal to the plane of motion for seated exercises. These findings show that some patient differences are linked to declines of normal aging and not that of the disorder. In addition patients took more steps at a slower pace for the gait with head movement exercise. The group differences in exercise kinematics guided the correlations between kinematics and functional data, so that the subject differences in correlations between actual function and head excursion kinematics differed from those for perceived function and head excursion kinematics. These data add to the limited findings on associations between kinematic measurements and functional performances in vestibular patients and are the first to show relationships exist between these measures for healthy young adults, healthy older adults and vestibular patients.



Document Availability at the Time of Submission

Release the entire work immediately for access worldwide.

Committee Chair

Hoffman, Paul