Vection in Depth during Consistent and Inconsistent Multisensory Stimulation

Abstract

We examined vection induced during physical or simulated head oscillation along either the horizontal or depth axis. In the first two experiments, during active conditions, subjects viewed radial-flow displays which simulated viewpoint oscillation that was either in-phase or out-of-phase with their own tracked head movements. In passive conditions, stationary subjects viewed playbacks of displays generated in earlier active conditions. A third control, experiment was also conducted where physical and simulated fore ^ aft oscillation was added to a lamellar flow display. Consistent with ecology, when active in-phase horizontal oscillation was added to a radial-flow display it modestly improved vection compared to active out-of-phase and passive conditions. However, when active fore ^ aft head movements were added to either a radial-flow or a lamellarflow display, both in-phase and out-of-phase conditions produced very similar vection. Our research shows that consistent multisensory input can enhance the visual perception of self-motion in some situations. However, it is clear that multisensory stimulation does not have to be consistent (ie ecological) to generate compelling vection in depth. Disciplines

Vection and cybersickness generated by head-and-display motion in the Oculus Rift

“…Because their screens are small and close to the eyes, screen positions and orientations relative to the eyes become important (e.g., incorrect interocular separations and/or HMD alignment on the head can lead to visual display artefacts). Different types of software projection errors are also possible, such as exaggerating/minimising the visual consequences of the tracked head motions [53], applying the compensatory visual motion along the wrong axis [54] or in the wrong direction [3,55], and accidently switching the left and the right eyes views of a stereo 3D simulation [56]. All of these display calibration and software errors would be more salient when the head is moving -and thus their potential for inducing cybersickness would also be expected to increase.…”

“…Four SSQ scores were calculated for each subject using methods and weighting factors outlined in [53]: a total SSQ score and three sub-scores (nausea, oculomotor symptoms, and disorientation). In each case pre-scores were subtracted from the post-scores.…”

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.…”

“…However, several recent studies appear to show that visually induced vection is surprisingly tolerant to a number of so-called "sensory conflict" situations Ash et al 2011a;Ash et al 2011b;Palmisano 2008, 2010;Palmisano et al 2011). For example, we have found that compelling vection can still be induced even when visual and non-visual self-motion stimulations are 180 degrees out-of-phase or indicate self-motion along completely different axes .…”

Virtual Swimming — Breaststroke Body Movements Facilitate Vection

“…Recently, Ash et al (2011) found that vection in depth could be increased by subjects actively moving their heads from left-and-right while viewing radial flow. Consistent with the findings of the current experiment, congruent (in-phase) horizontal head-and-display movements increased vection more than incongruent (180º out-of-phase) horizontal head-and-display movements.…”