Purpose:
Walking demands controlling body segments based on sensory information. Experimental manipulation of sensory information provides insight about how it interacts in situations of occlusion or perturbation of such information. This study examined the effect of manipulation of visual and vestibular information on spatial perception during gait.

Methods:
Thirty-two participants aged between 19-34 years old walked straight ahead for 7 meters to reach the center point of the pathway. The authors measured the number of steps, movement time, and absolute error (deviation from the center of pathway end). They analyzed six experimental conditions: without spin with vision, without spin with visual occlusion, without spin with visual perturbation, with spin and vision, with spin and visual occlusion, and with spin and visual perturbation. Friedman's ANOVA test was used to compare the experimental conditions with a significance of 5% (p < 0.05).

Results:
Occlusion and perturbation of visual information, and the perturbation of vestibular information, both affected the spatial orientation. The more sources of information that were occluded and/or perturbed; the greater was the decline of spatial perception. However, participants were able to perform the task of walking in all conditions with the manipulation of sensory information.

Conclusions:
The authors suggest that there is a dynamic hierarchy in which the sensory sources can contribute in a particular way, due to the constraint imposed on the system.