Visual Context Influences Lateral Balance While Walking on Winding Paths

Effectively navigating daily environments necessitates achieving adaptability while maintaining stability. This requires integrating sensory feedback, primarily from the visual system, to maintain balance and maneuverability as we walk. This study examined the impact of visual information salience on lateral balance and stepping. Twenty-eight healthy adults (16F/12M; 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 outside designated path boundaries. We computed means ( <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mi>μ</mml:mi></mml:math> ) and standard deviations ( <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mi>σ</mml:mi></mml:math> ) of the minimum mediolateral margins of stability (<i>MoS</i> _<i>L</i> ), and we computed lateral Probability of Instability ( <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mi>P</mml:mi> <mml:mi>o</mml:mi> <mml:msub><mml:mrow><mml:mi>I</mml:mi></mml:mrow> <mml:mrow><mml:mi>L</mml:mi></mml:mrow> </mml:msub> </mml:math> ) to assess participants' risk of taking unstable (<i>MoS</i> _<i>L</i> < 0) steps. On Straight paths, participants made more stepping errors on Low (vs. High) contrast paths for both environments, and exhibited decreased <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mi>σ</mml:mi> <mml:mfenced><mml:mrow><mml:mi>M</mml:mi> <mml:mi>o</mml:mi> <mml:msub><mml:mrow><mml:mi>S</mml:mi></mml:mrow> <mml:mrow><mml:mi>L</mml:mi></mml:mrow> </mml:msub> </mml:mrow> </mml:mfenced> </mml:math> 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 <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mi>μ</mml:mi> <mml:mfenced><mml:mrow><mml:mi>M</mml:mi> <mml:mi>o</mml:mi> <mml:msub><mml:mrow><mml:mi>S</mml:mi></mml:mrow> <mml:mrow><mml:mi>L</mml:mi></mml:mrow> </mml:msub> </mml:mrow> </mml:mfenced> </mml:math> and exhibited higher <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mi>P</mml:mi> <mml:mi>o</mml:mi> <mml:msub><mml:mrow><mml:mi>I</mml:mi></mml:mrow> <mml:mrow><mml:mi>L</mml:mi></mml:mrow> </mml:msub> </mml:math> on Low Contrast paths in both environments, and they exhibited higher <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mi>P</mml:mi> <mml:mi>o</mml:mi> <mml:msub><mml:mrow><mml:mi>I</mml:mi></mml:mrow> <mml:mrow><mml:mi>L</mml:mi></mml:mrow> </mml:msub> </mml:math> in Sparse environments on paths of both visual contrasts. The effects of diminished visual information were far more pronounced on Winding paths (vs. Straight), hindering performance and balance maintenance, as these conditions challenged both mechanical and sensory mechanisms underlying balance control.