July 2013
Volume 13, Issue 9
Free
Vision Sciences Society Annual Meeting Abstract  |   July 2013
Accuracy of walking direction with and without visual feedback
Author Affiliations
  • Jeffrey Saunders
    Department of Psychology, University of Hong Kong
Journal of Vision July 2013, Vol.13, 953. doi:10.1167/13.9.953
  • Views
  • Share
  • Tools
    • Alerts
      ×
      This feature is available to Subscribers Only
      Sign In or Create an Account ×
    • Get Citation

      Jeffrey Saunders; Accuracy of walking direction with and without visual feedback. Journal of Vision 2013;13(9):953. doi: 10.1167/13.9.953.

      Download citation file:


      © ARVO (1962-2015); The Authors (2016-present)

      ×
  • Supplements
Abstract

Direction of self-motion during walking is indicated by multiple cues, including optic flow, non-visual sensory cues, and motor prediction. I measured the variability in walking direction with and without visual feedback, and tested whether visual and non-visual cues are weighted in an optimal manner. Open-loop walking in an immersive virtual environment was used to assess the accuracy of perceived walking direction. Observers walked toward a target 4m away either with no vision, or vision during the first 1m of walking. Three simulated environments were tested: target-only, target and textured ground, or target with textured ground and scattered posts. With no vision, variability in walking direction averaged 3°. Visual feedback during initial movement reduced variability to about 1.5°, regardless of visual environment. These results show that observers are capable of initiating movement toward a target with reasonable accuracy, but that even a limited amount of visual feedback significantly improves accuracy. Based on these measures, an optimal estimator would strongly weigh visual information. A second experiment measured the perceptual weighting of visual and non-visual cues. Optic flow specified a conflicting heading direction (±5°), and bias in walking direction was used to infer cue weights. Visual heading had a significant effect on walking direction, but the estimated visual weights were smaller than predicted (33-43% vs. 71%), and varied depending on the visual environment. Non-visual information appeared to have more influence than expected given the relative reliability of cues.

Meeting abstract presented at VSS 2013

×
×

This PDF is available to Subscribers Only

Sign in or purchase a subscription to access this content. ×

You must be signed into an individual account to use this feature.

×