Abstract
Locomotion requires some degree of cognitive demand and involvement of executive functions including inhibition, updating, and task switching. Secondary tasks that require cognitive demand can impact our walking performance. Online visual information and executive functions coordinate how we navigate and progress safely through our environment, for example, avoiding ice in the winter or stopping at a cross walk. This study explored how inhibition, updating, and task switching are used during a visually guided targeted stepping and obstacle avoidance task. Participants walked along a straight walkway and stepped on or over a colour changing rectangular obstacle (42x20x5cm). The obstacle would change from white to red or green during approach. Instructions given to the participant coupled with the light change would result in a specific response: Preliminary instructions (green=on, red=over); Switched Instructions (green=over, red=on). It was expected that the switched instructions would pose an increased cognitive demand and subsequently result in a decrease in performance. The following gait measures were analyzed 1) Foot placement accuracy 2) maximum head tilt angle 3) Center of mass (COM) velocity. To date, our preliminary data for young adults (N=6) have shown that foot placement was most accurate in medial lateral direction (<1cm error) compared to anterior-posterior (AP). In the AP direction, foot placement accuracy was highest for the preliminary instructions with green lights (on) and least accurate in the switched instructions with green lights (over). This suggests that with increased cognitive demand, there is a decrease in motor accuracy. Data analyses and collection are ongoing. These findings will help further our understanding about the impact of complex visual cues on targeted stepping and obstacle avoidance tasks.