Date of Award


Degree Type


Degree Name

Master of Science in Vision Science

Committee Chair

Bradley Coffey

Second Advisor

Alan W. Reichow


Certain functions of the visual system may be affected by sustained cognitive demand tasks which are common in non-dynamic sports such as pistol shooting, diving, golf and others. 31 undergraduate and 9 graduate students from Pacific University were visually evaluated before and after a thirty-minute period of intense cognitive activity. The test battery consisted of four visual evaluation areas: Contrast sensitivity, stereosensitivity, fixation disparity, and a perceptual speed task. A set of 480 simple addition and subtraction equations were used as a cognitive task to induce fatigue. Data analysis revealed significant differences in post-fatigue trials in all areas evaluated except contrast sensitivity. It was found in post-fatigue trials that fixation disparity became less exo, perceptual abilities on a speed task improved, and stereosensitivity decreased. These changes were attributed to a heightened cognitive level secondary to the mental task. It was the goal of this study to simulate non-dynamic sport conditions by inducing mental fatigue. The visual changes found in this study may contribute to inconsistent performance in non-dynamic sports which emphasize concentration that induces mental fatigue.

Included in

Optometry Commons