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Abstract
Concussions are a growing public health concern, with rising incidence across all levels of sport and age groups. Among the many consequences of concussion, visual dysfunction is both highly prevalent and underexamined despite over half of the brain being dedicated to visual processing. Most clinical assessments emphasize oculomotor control, often neglecting sensory and perceptual components that may be more sensitive to lingering post-concussion deficits. Additionally, few studies have explored how visual disturbances affect gait performance, particularly under real-world visual stressors like glare. This dissertation aimed to evaluate visual performance in individuals with and without a history of concussion using a novel psychophysical battery, and to examine how glare exposure influences gait performance across simple and complex gait tasks. Thirty-one participants (16 with a concussion history, 15 matched controls) completed assessments of macular pigment optical density, temporal contrast sensitivity, critical flicker fusion threshold, and glare sensitivity/discomfort. Gait was assessed during straight path walking and planned/unplanned gait termination, with and without glare exposure administered via mobile glare goggles. There were no significant group differences in visual or gait outcomes. However, glare significantly altered gait in all participants, reducing stride length and velocity and increasing gait termination time specifically during unplanned gait termination. These findings suggest that even in asymptomatic individuals, visual stressors like glare can affect motor control. Although group differences were not detected, this study introduces novel tools that may have the ability to uncover subtle impairments overlooked by standard clinical measures. The integration of gait analysis under glare conditions offers a promising framework for advancing concussion assessment within everyday scenarios. These findings emphasize the importance of considering visual disturbances in post-concussion care and highlight the need for more comprehensive, real-world evaluations to inform recovery and return-to-activity decisions.