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Date of Award


Degree Type

Thesis (On-Campus Access Only)

Degree Name

Master of Physical Therapy (MPT)

First Advisor

Daiva Banaltis, PhD, PT

Second Advisor

Ann Williams, PhD, PT


The study was designed to examine the effects of decreased peripheral vision on postural sway under three different conditions. Thirty-nine healthy subjects (33 women, 6 men, from 40 to 84 years of age) participated in this study. Subjects were divided into four different age categories (40-49, 50-59, 60-69, and 70 & up). Postural sway was measured under static, dynamic and reduced somatosensation conditions as peripheral vision was artificially reduced by increments of 30 degrees initially beginning from normal peripheral vision. Postural sway area was measured with normal vision and with 90, 60, and 30 degrees of peripheral vision using a computerized force plate system. One factorial analysis of variance was used to analyze the effects of decreased peripheral vision on the three conditions for each age group. Under the static condition, decreased peripheral vision did not effect postural sway. Under' dynamic conditions, as peripheral vision was decreased postural sway area increased, although the overall amount of sway declined with age. Finally, under reduced somatosensory conditions there was a subtle increase in postural sway as peripheral vision was decreased.


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