Natural Visual-Field Features Enhance Vection

Abstract

When a large optic-flow pattern is viewed, induced self-motion perception (vection) can result even for observers who are stationary relative to Earth. Vection is common in optokinetic drums, large-screen cinemas, vehicle simulators, and other virtual environments. However, not all optic-flow patterns are equally effective in producing vection. We hypothesized that visual-field characteristics that typically accompany self-motion are likely to facilitate vection. The two characteristics tested in the current study were color and global visual-field movement consistent with head bob and sway that occurs when a person walks or runs. Stationary observers viewed first-person perspective video clips on a rear-projection screen that depicted forward self-motion. Vection onset and magnitude were measured with a computer-interfaced slide device. In experiment 1, either a grayscale or color video was presented. In experiment 2, the video was shot either from a smooth rolling cart or with a hand-held camera that yielded gait information in addition to global expansion. Vection onset was found to be faster, and stronger in magnitude, when videos containing color and gait movements were viewed. These results suggest that visual-field features that are common during actual self-motion can enhance vection in a virtual environment, resulting in a more realistic experience for viewers.

Simulated Viewpoint Jitter Shakes Sensory Conflict Accounts of Vection

“…Research suggests that viewpoint jitter and oscillation improve the vection experience by tapping into specialized processes used to perceive self-motion from naturally occurring patterns of optic flow (Bubka and Bonato, 2010;. While some recent research suggests that simulated viewpoint oscillation may improve vection by increasing the perceived rigidity of the optic flow (Nakamura, 2010), other evidence suggests that the mechanisms underlying these jitter/oscillation based improvements may be increased retinal slip (Palmisano and Kim, 2009) or reduced adaptation.…”

“…Consistent with this notion, Lécuyer and colleagues (2006) have found that adding simulated head oscillation to their radial flow displays significantly increased reported sensations of walking by their subjects (relative to no-oscillation control displays). Similarly, a recent study by Bubka and Bonato (2010) has shown that first-person videos shot from a hand-held camera induce faster vection onsets and longer vection durations than comparable videos shot from a rolling cart.…”

Vection depends on perceived surface properties

“…These displays were not designed to simulate the reflectance properties of natural surfaces. Although a few studies have examined the vection induced by moving surfaces with complex reflectance profiles (e.g., by using computer-generated imagery in Riecke et al, 2006, or real-world image sequences in Bubka & Bonato, 2010), they were not designed to identify the relative contributions of diffuse and specular shading to selfmotion perception. By contrast, in Experiment 1 we used computer graphics to examine the independent effects of the diffuse and specular optic flow components on vection in depth.…”

Walking without optic flow reduces subsequent vection

“…A number of recent studies suggest that such visually-mediated self-motion perceptions can be facilitated by physically moving the observer in a manner consistent with the visual simulation (Berger et al 2010;Wong and Frost 1981;Wright, 2009;Bubka and Bonato 2010) or by incorporating active head motions of the observer directly into the self-motion display (Ash et al 2011a;Ash et al 2011b). 1 When taken together, such findings suggest that consistent multisensory stimulation may produce a more compelling overall experience of self-motion than visual self-motion stimulation alone.…”