Veering re-visited: noise and posture cues in walking without sight

Effects of sound and posture cues on veering from the straight-ahead were t ested with young blind children in an unfamiliar space that lacked orientin g cues. In a pre-test with a previously heard target sound, all subjects wa lked straight to the target. A recording device, which sampled the locomoto r trajectories automatically, showed that, without prior cues from target l ocations, subjects tended to veer more to the side from which they heard a brief, irrelevant noise. Carrying a load on one side produced more veering to the opposite side. The detailed samples showed that, underlying the main trajectories, were alternating concave and convex (left and right) movemen ts, suggesting stepwise changes in body position. It is argued that the sam e external and body-centred cues that contribute to reference-frame orienta tion for locomotion when they converge and concur, influence the direction of veering when the cues occur in isolation in environments that lack conve rging reference information.