Looking where you are going does not help path perception

Abstract

It has been mathematically shown that when travelling on a circular path and fixating a target on the future path, flow lines for environmental points on the path would be vertical. Here we test whether fixating a target on the future path helps path perception. Observers viewed displays (110°Hx94°V) simulating their traveling on a circular path over a textured ground (T=3 m/s, R=±3°/s or ±6°/s) for 1 s. Three display conditions were tested. In the path-fixation condition, the simulated gaze direction in the display pointed to a target along the path at 20° away from the starting position; in the non-path-fixation condition, the simulated gaze direction was on a target 10° inside or outside the path at the same distance; and in the heading-fixation condition, the simulated gaze pointed to the instantaneous heading (i.e., the tangent to the path). At the end of the trial, observers used a mouse to place the probe (10 m) on their perceived future path. We found that path perception largely depends on solving the translation and rotation problem in retinal flow, fixating a target on the future path does not help the perception of the path trajectory.