The Effect of a Concomitant Cognitive Task on One’s Unperceived Displacement and Knee Height in Stepping in Place Without Vision: A Kinematic Study

Abstract

While stepping in place without vision, individuals displace linearly and rotate, without perceiving these displacements. The aims of this study were to evaluate the effect of a concomitant cognitive task and the influence of knee height on these displacements in stepping in place for 50 steps. Sixteen adults (mean age = 22 years) performed four conditions of stepping: normal knee height and high knee height with and without a cognitive task. Antero-posterior (AP) displacement was significantly smaller in dual task than in single task at normal knee height, and AP and medio-lateral displacements were significantly larger at high than at normal knee height for single and dual task. No changes in body rotation were found. These findings suggest that automaticity is involved in the control of stepping in place with a concurrent cognitive task and that one’s attentional capacity is exceeded when stepping in place with high knees and a cognitive task.