Influence of head orientation and viewpoint oscillation on linear vection¹

Issue title: 8th Symposium on the Role of the Vestibular Organs in Space Exploration April 8–10, 2011, Houston, TX, USA

Guest editors: Charles M. Oman

Article type: Research Article

Authors: Guterman, Pearl S.^{a; *} | Allison, Robert S.^a | Palmisano, Stephen^b | Zacher, James E.^a

Affiliations: [a] Centre for Vision Research, York University, Toronto, ON, Canada | [b] School of Psychology, University of Wollongong, Wollongong, NSW, Australia | Man Vehicle Laboratory, Massachusetts Institute of Technology, Cambridge, MA, USA

Correspondence: [*] Corresponding author: Pearl S. Guterman, Centre for Vision Research, York University, 4700 Keele Street, Toronto, ON, M3J 1P3, Canada. Tel.: +1 416 736 2100 x20192, Fax: +1 416 736 5872; E-mail: [email protected]

Note: [1] This paper was presented at the Session: Poster at the 8th Symposium on the Role of the Vestibular Organs in Space Exploration, April 8–10, 2011, Houston, TX, USA

Abstract: Sensory conflict theories predict that adding simulated viewpoint oscillation to self-motion displays should generate significant and sustained visual-vestibular conflict and reduce the likelihood of illusory self-motion (vection). However, research shows that viewpoint oscillation enhances vection in upright observers. This study examined whether the oscillation advantage for vection depends on head orientation with respect to gravity. Displays that simulated forward/backward self-motion with/without horizontal and vertical viewpoint oscillation were presented to observers in upright (seated and standing) and lying (supine, prone, and left side down) body postures. Viewpoint oscillation was found to enhance vection for all of the body postures tested. Vection also tended to be stronger in upright postures than in lying postures. Changing the orientation of the head with respect to gravity was expected to alter the degree/saliency of the sensory conflict, which may explain the overall posture-based differences in vection strength. However, this does not explain why the oscillation advantage for vection persisted for all postures. Thus, the current postural and oscillation based vection findings appear to be better explained by ecology: Upright postures and oscillating flow (that are the norm during self-motion) improved vection, whereas lying postures and smooth optic flows (which are less common) impaired vection.

Keywords: Vection, sensory conflict, head orientation, posture, optic flow, linear, oscillation

DOI: 10.3233/VES-2012-0448

Journal: Journal of Vestibular Research, vol. 22, no. 2-3, pp. 105-116, 2012