Abstract
Purpose :
Visual perception of object-motion and self-motion is critical for safe mobility. However, the risks of accidents and falls during mobility increase with age, presumably due to functional vision loss. We used head-mounted display (HMD) virtual reality (VR) as a tool to understand how the visual perception of self-motion and presence (the feeling of being “there”) varies with age.
Methods :
Eighty-six (86) healthy participants aged 18 to 77 (37 females) with normal or corrected to normal visual acuities and normal visual fields were recruited for this study. We measured illusory self-motion perception (vection) and presence when participants viewed radially expanding patterns of optic flow. Optic flow was generated using a HMD VR (Oculus Rift CV1) to simulated different speeds of self-motion. Viewing was performed with the head stationary (passive condition) or with lateral-sway head movements (active conditions).
Results :
Presence increased with age (F 2,83 = 5.44, p < 0.01). Vection did not significantly change with age (F 2,83 = 1.82, p = 0.17). However, head movements had a significant impact on perceived vection (F 2,166 = 19.84, p < 0.001). A significant interaction was also found between age and viewing condition (F 4,166 = 3.60, p < 0.01). Main effects of simulated speed on perceived vection (F 3,249 = 367.89, p < 0.001) and presence (F 3,249 = 112.64, p < 0.001) were also found. These results show vection increases with the speed of simulated self-motion, but generally decreases with increasing age (Figure 1).
Conclusions :
This study shows there are age-related changes in the perception of self-motion and spatial presence in HMD VR. Our findings suggest that the experience of self-motion perception decreases with age, particularly at slow speeds consistent with normal walking. This may provide further clues to why the elderly have increased risk of accidents and falls.
This is a 2021 ARVO Annual Meeting abstract.