Peripheral visual cues affect minimum-foot-clearance during overground locomotion

• Published in: Gait & posture Vol. 30; no. 3; pp. 370 - 374
• Main Authors: Graci, Valentina, Elliott, David B., Buckley, John G.
• Format: Journal Article
• Language: English
• Published: England Elsevier B.V 01.10.2009
• Subjects: Adaptation, Physiological - physiology; Adult; Analysis of Variance; Biomechanical Phenomena; Cues; Environment; Eye Protective Devices; Female; Foot; Humans; Locomotion - physiology; Male; Minimum-foot-clearance; Online control; Orthopedics; Overground locomotion; Peripheral visual cues; Psychomotor Performance - physiology; Visual exproprioception; Visual Fields - physiology; Visual Perception - physiology; Walking - physiology; Online control; Peripheral visual cues; Overground locomotion; Visual exproprioception; Minimum-foot-clearance
• ISSN: 0966-6362; 1879-2219; 1879-2219
• DOI: 10.1016/j.gaitpost.2009.06.011

The importance of peripheral visual cues in the control of minimum-foot-clearance during overground locomotion on a clear path was investigated. Eleven subjects walked at their natural speed whilst wearing goggles providing four different visual conditions: upper occlusion, lower occlusion, circumferential–peripheral occlusion and full vision. Results showed that under circumferential–peripheral occlusion, subjects were more cautious and increased minimum-foot-clearance and decreased walking speed and step length. The minimum-foot-clearance increase can be interpreted as a motor control strategy aiming to safely clear the ground when online visual exproprioceptive cues from the body are not available. The lack of minimum-foot-clearance increase in lower occlusion suggests that the view of a clear pathway from beyond two steps combined with visual exproprioception and optic flow in the upper field were adequate to guide gait. A suggested accompanying safety strategy of reducing the amount of variability of minimum-foot-clearance under circumferential–peripheral occlusion conditions was not found, likely due to the lack of online visual exproprioceptive cues provided by the peripheral visual field for fine-tuning foot trajectory.