Background Navigating daily environments necessitates adapting to ever-changing conditions while maintaining stability. This requires integrating sensory feedback, primarily from vision, to maintain balance and maneuverability as we walk. Research Question What is the impact of diminished visual information salience on lateral balance and stepping? Methods Twenty-eight healthy adults (16 F/12 M; 26.16 ± 4.23 years) participated. Participants walked along each of two virtual paths (Straight vs. Winding), having each of two path color contrasts (High vs. Low), in each of two environments with differing visual richness (Rich vs. Sparse). We quantified stepping errors as the percentage of steps landing off the designated path. We computed means (μ) and standard deviations (σ) of minimum mediolateral margins of stability (MoSL). We computed lateral Probability of Instability (PoIL) to quantify participants’ risk of taking unstable (MoSL < 0) steps. Results On Straight paths, participants made more stepping errors on Low (vs. High) contrast paths for both environments, and exhibited decreased σ(MoSL) in Sparse (vs. Rich) environments on paths of both visual contrasts. On Winding paths, participants made the most stepping errors on Low Contrast paths in Sparse environments. They walked with smaller μ(MoSL) and exhibited higher PoIL on Low Contrast paths in both environments, and they exhibited higher PoIL in Sparse environments on paths of both visual contrasts. Effects of diminished visual information were far more pronounced on Winding vs. Straight paths. Significance Diminished visual information salience hinders stepping performance and lateral balance, especially when walking conditions challenge both mechanical and sensory mechanisms underlying balance control.
