Abstract
[Purpose] The purpose of this study was to examine the center of pressure (COP) trajectory and response time when young adults initiate gait and step over an obstacle while simultaneously performing a secondary Stroop task. [Subjects] Twenty healthy young adults (ten males and ten females) participated in the study. [Methods] The subjects first completed a Stroop task while standing (baseline) and then initiated gait and stepped over an obstacle at a self-paced speed with and without a secondary Stroop task. The response times to the secondary task and the COP trajectory were measured. [Results] The Stroop task response time in the stepping condition was the longest, followed by the times for initiating gait and standing conditions (p<0.01). There were main effects for both the Stroop task and stepping conditions for the mediolateral (M-L) displacement of the COP and the length of the COP path for both feet (p<0.01, respectively). However, there were no significant differences among the tasks for the anteroposterior (A-P) displacement of the COP for both feet. [Conclusion] This study suggests that divided attention degrades the obstacle avoidance abilities of healthy young adults and the apparently greater demand of postural control may prove as difficult for populations that are at risk of falling.
