Limits...
Evidence against an ecological explanation of the jitter advantage for vection.

Palmisano S, Allison RS, Ash A, Nakamura S, Apthorp D - Front Psychol (2014)

Bottom Line: One possible explanation of this jitter advantage for vection is that jittering optic flows are more ecological than smooth displays.Despite the intuitive appeal of this idea, it has proven difficult to test.As expected, the (more naturalistic) treadmill walking and the (less naturalistic) walking in place were found to generate very different physical head jitters.

View Article: PubMed Central - PubMed

Affiliation: School of Psychology, University of Wollongong Wollongong, NSW, Australia.

ABSTRACT
Visual-vestibular conflicts have been traditionally used to explain both perceptions of self-motion and experiences of motion sickness. However, sensory conflict theories have been challenged by findings that adding simulated viewpoint jitter to inducing displays enhances (rather than reduces or destroys) visual illusions of self-motion experienced by stationary observers. One possible explanation of this jitter advantage for vection is that jittering optic flows are more ecological than smooth displays. Despite the intuitive appeal of this idea, it has proven difficult to test. Here we compared subjective experiences generated by jittering and smooth radial flows when observers were exposed to either visual-only or multisensory self-motion stimulations. The display jitter (if present) was generated in real-time by updating the virtual computer-graphics camera position to match the observer's tracked head motions when treadmill walking or walking in place, or was a playback of these head motions when standing still. As expected, the (more naturalistic) treadmill walking and the (less naturalistic) walking in place were found to generate very different physical head jitters. However, contrary to the ecological account of the phenomenon, playbacks of treadmill walking and walking in place display jitter both enhanced visually induced illusions of self-motion to a similar degree (compared to smooth displays).

No MeSH data available.


Related in: MedlinePlus

Effects of Walking Type (Treadmill Walking versus Walking in Place), display type (smooth versus jitter) and Simulated Speed (4 or 5 km/h) on the strength of the perceived self-motion in depth. Error bars represent SEMs.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4227477&req=5

Figure 8: Effects of Walking Type (Treadmill Walking versus Walking in Place), display type (smooth versus jitter) and Simulated Speed (4 or 5 km/h) on the strength of the perceived self-motion in depth. Error bars represent SEMs.

Mentions: A second repeated-measures ANOVA compared the multisensory perceptions of forward self-motion when participants viewed optic flow displays while treadmill walking and walking in place. The independent variables examined were walking type (treadmill walking and walking in place), display type (smooth and jittering) and simulated speed (4 and 5 km/h). We found no main effect of walking type (F1,18 = 0.04, p> 0.05), which indicated that ratings of the strength of forward self-motion were not significantly different during walking in place and treadmill walking conditions. We also found a significant main effect of simulated speed (F1,18 = 43.31, p < 0.0001), indicating that faster simulated speeds generated stronger ratings of forward self-motion (see Figure 8). Importantly we also found a significant main effect of display type (F1,18 = 25.27, p < 0.0001), which indicated that jittering displays produced stronger self-motion ratings than smooth displays (see Figure 8). The walking type by display type interaction was not significant (F1,18 = 1.84, p> 0.05), suggesting that treadmill-walking generated jitter and walking in place generated jitter produced very similar advantages/enhancements in terms of the rated experience of self-motion. No other two- or three-way interactions were significant (p > 0.05 in all cases).


Evidence against an ecological explanation of the jitter advantage for vection.

Palmisano S, Allison RS, Ash A, Nakamura S, Apthorp D - Front Psychol (2014)

Effects of Walking Type (Treadmill Walking versus Walking in Place), display type (smooth versus jitter) and Simulated Speed (4 or 5 km/h) on the strength of the perceived self-motion in depth. Error bars represent SEMs.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4227477&req=5

Figure 8: Effects of Walking Type (Treadmill Walking versus Walking in Place), display type (smooth versus jitter) and Simulated Speed (4 or 5 km/h) on the strength of the perceived self-motion in depth. Error bars represent SEMs.
Mentions: A second repeated-measures ANOVA compared the multisensory perceptions of forward self-motion when participants viewed optic flow displays while treadmill walking and walking in place. The independent variables examined were walking type (treadmill walking and walking in place), display type (smooth and jittering) and simulated speed (4 and 5 km/h). We found no main effect of walking type (F1,18 = 0.04, p> 0.05), which indicated that ratings of the strength of forward self-motion were not significantly different during walking in place and treadmill walking conditions. We also found a significant main effect of simulated speed (F1,18 = 43.31, p < 0.0001), indicating that faster simulated speeds generated stronger ratings of forward self-motion (see Figure 8). Importantly we also found a significant main effect of display type (F1,18 = 25.27, p < 0.0001), which indicated that jittering displays produced stronger self-motion ratings than smooth displays (see Figure 8). The walking type by display type interaction was not significant (F1,18 = 1.84, p> 0.05), suggesting that treadmill-walking generated jitter and walking in place generated jitter produced very similar advantages/enhancements in terms of the rated experience of self-motion. No other two- or three-way interactions were significant (p > 0.05 in all cases).

Bottom Line: One possible explanation of this jitter advantage for vection is that jittering optic flows are more ecological than smooth displays.Despite the intuitive appeal of this idea, it has proven difficult to test.As expected, the (more naturalistic) treadmill walking and the (less naturalistic) walking in place were found to generate very different physical head jitters.

View Article: PubMed Central - PubMed

Affiliation: School of Psychology, University of Wollongong Wollongong, NSW, Australia.

ABSTRACT
Visual-vestibular conflicts have been traditionally used to explain both perceptions of self-motion and experiences of motion sickness. However, sensory conflict theories have been challenged by findings that adding simulated viewpoint jitter to inducing displays enhances (rather than reduces or destroys) visual illusions of self-motion experienced by stationary observers. One possible explanation of this jitter advantage for vection is that jittering optic flows are more ecological than smooth displays. Despite the intuitive appeal of this idea, it has proven difficult to test. Here we compared subjective experiences generated by jittering and smooth radial flows when observers were exposed to either visual-only or multisensory self-motion stimulations. The display jitter (if present) was generated in real-time by updating the virtual computer-graphics camera position to match the observer's tracked head motions when treadmill walking or walking in place, or was a playback of these head motions when standing still. As expected, the (more naturalistic) treadmill walking and the (less naturalistic) walking in place were found to generate very different physical head jitters. However, contrary to the ecological account of the phenomenon, playbacks of treadmill walking and walking in place display jitter both enhanced visually induced illusions of self-motion to a similar degree (compared to smooth displays).

No MeSH data available.


Related in: MedlinePlus