Lauren Hoare¹, Krista Kelly¹; ¹School of Optometry and Vision Science, University of Waterloo

Introduction: Eye-body coordination is important for locomotion, with children shifting from relying largely on vision to integrating vestibular and sensorimotor cues around 7-9 years of age. Compared to adults, children 2-6 years slow down, look down more often, and move their eyes more while walking on uneven ground (Schroer & Hayhoe, 2025 VSS meeting). Here, we examine eye-body coordination during walking in conditions of increasing complexity in children 7-13 years. Methods: 28 typically-developing children were enrolled (13 younger, 7-9 years; 15 older, 10-13 years). Children completed 3 walking conditions: 1) Straight Walk (SW): walk on mat, 2) Isolated Target Walk (IT): walk and step on two-dimensional (2D) targets, and 3) Distractor Target Walk (DT): walk and step on 2D targets while avoiding 2D distractors. Gait outcomes recorded with the GAITRite pressure-sensitive walkway were normalized velocity, stepping accuracy, and coefficient of variability (COV). Eye movement outcomes recorded with the Tobii Glasses 2 were looking time and average number of fixations in areas of interest on the mat (nothing, target, distractor). Results: Younger children walked faster than older children in all 3 conditions (ps<0.001), and had higher COV (i.e., more variability) for normalized velocity (p=0.012) and step width (p=0.016) in the SW condition only. Younger children were also less accurate at stepping on the far target (p=0.012), but not the near target or distractors (ps>0.057). During walking, younger children looked more (p=0.042) and made more fixations (p=0.019) in areas with targets or distractors compared to older children. Conclusion: Compared to older children, younger children walked faster, were more variable and less accurate, and made more fixations to targets and distractors in their path. This pattern of eye-body coordination may reflect more reliance on visual feedback during the development of walking as younger children build strategies for more efficient planning and execution.

Acknowledgements: NSERC Discovery Grant RGPIN-2024-03992 (KK), Canadian Optometric Education Trust Fund (LH)