Effects of Conflict-Induced Cognitive Load on Reactive Turning Strategies and Postural Control Timing

Reactive turning requires considerable cognitive resources and precise motor control to maintain dynamic balance. Increased cognitive load can impair motor performance and alter turning behavior. This study examined how cognitive load and cue timing influence reactive turning strategies and postural control timing. Nineteen healthy young adults performed 90° contralateral and ipsilateral reactive turns while walking and completing a flanker task under varying cue timings and conflict conditions. Turning strategies and temporal parameters (head/pelvis rotation and center of mass deceleration times) were analyzed using linear mixed models; sensitivity analyses additionally adjusted for turning strategy. Under conflict, participants maintained near-perfect directional accuracy; however, temporal parameters were significantly delayed. These delays persisted after accounting for strategy switching, suggesting that cognitive interference influenced the temporal organization of reactive turning. Turning strategy selection was primarily associated with cue timing, with no significant effect of cognitive conflict. Furthermore, when temporal constraints limited the feasibility of a prompt second-step turn, contralateral turns shifted toward a mechanically stable third-step reorganization, whereas ipsilateral turns relied on a less stable alternative. Overall, these findings suggest that cognitive load modulates the temporal coordination of postural control during reactive turning without altering the selected turning strategy.