Abstract
INTRODUCTION: Individuals attempt to equalize the amount of space between the shoulders and obstacles, by walking through an aperture's center. Path selection is determined by goal attraction, individuals walk through the center of an aperture because the attraction is pulling them there. However, it is unclear whether the attraction originates from the aperture's center or the end goal. The purpose of the current study was to decipher the possible location of the attracter, by evaluating crossing behaviour for multiple, misaligned apertures. METHODS: Participants were instructed to walk through three apertures towards an end goal. The first and last aperture widths were coupled and were either 0.9x or 1.7xSW, the second aperture was either 0.9, 1.3, or 1.7xSW and shifted 25, 50, or 75cm from the path's midline. RESULTS: Findings revealed that the attraction of the end goal, and not the middle of the aperture, guided crossing behaviour evident by the fact that the COM position at the time of crossing was closer to the obstacle nearest midline (F(2, 36) = 362.33, p< .001) and the space between the shoulder and obstacle closest to midline decreased as the shift magnitude increased (F(2, 36) = 52.47, p< .001). Furthermore, as the middle aperture shift increased, individuals rotated their shoulders more often (F(2, 36) = 11.25, p< .001) regardless of the aperture size. It is believed that rotations were produced in an attempt to keep one's trajectory as close to the midline as possible because rotations would not normally occur for all aperture sizes when it is aligned with goal. CONCLUSION: Not only does the attraction of the goal guide path trajectory, but individuals reduce the spatial margin and rotate the shoulders when walking through misaligned apertures, likely in attempt to maintain the straightest possible path.
Meeting abstract presented at VSS 2016