The control of visual attention by the demands of locomotion – implications for movement disorders and their clinical diagnosis

For sighted individuals, normal everyday activities such as walking down a busy street or through a crowded grocery store are based on using vision to identify not just where one is headed, but what obstacles and hazards need to be avoided as well. While this ability to visually guide our actions may appear effortless, the task requires a complex coupling between the visual and motor systems. When disease or brain injury compromises these links between the visual and motor systems it becomes acutely obvious how much the brain is doing behind the scenes to promote normal motor behaviour. Most research on visual attention and its role in normal cognitive function has long centered on describing how it helps to recognize and identify objects in the visual world. Dr. Todd Handy’s research examines the reverse: the effect movements and locomotion have on vision, which is a previously unexplored facet of visual-motor interactions. Using a system that provides video-simulated motion and measurements of brain activity, Dr. Handy is studying how visual attention automatically responds to the many perceptual demands of locomotion - keeping track of the direction one is heading, recognizing stationary obstacles that may be looming in the path, and noticing moving objects in the periphery that may ultimately be on a collision course without conscious attention to these elements. Dr. Handy hopes his research will contribute to a better understanding of these visual-motor interactions and may provide a promising new method of diagnosing clinical motor disorders.