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Vection During Conflicting Multisensory Information About The Axis, Magnitude And Direction Of Self-Motion, April Ash, Stephen Palmisano
Vection During Conflicting Multisensory Information About The Axis, Magnitude And Direction Of Self-Motion, April Ash, Stephen Palmisano
Faculty of Health and Behavioural Sciences - Papers (Archive)
We examined the vection induced by consistent and conflicting multisensory information about self-motion. Observers viewed displays simulating constant-velocity self-motion in depth while physically oscillating their heads left ^ right or back ^ forth in time with a metronome. Their tracked head movements were either ignored or incorporated directly into the self-motion display (as an added simulated self-acceleration). When this head oscillation was updated into displays, sensory conflict was generated by simulating oscillation along: (i) an orthogonal axis to the head movement; or (ii) the same axis, but in a non-ecological direction. Simulated head oscillation always produced stronger vection than `no …
Simulated Angular Head Oscillation Enhances Vection In Depth, Juno Kim, Stephen Palmisano, Frederick Bonato
Simulated Angular Head Oscillation Enhances Vection In Depth, Juno Kim, Stephen Palmisano, Frederick Bonato
Faculty of Health and Behavioural Sciences - Papers (Archive)
Research has shown that adding simulated linear head oscillation to radial optic flow displays enhances the illusion of self-motion in depth (ie linear vection). We examined whether this oscillation advantage for vection was due to either the added motion parallax or retinal slip generated by insufficient compensatory eye movement during display oscillation. We constructed radial flow displays which simulated 1 Hz horizontal linear head oscillation (generates motion parallax) or angular head oscillation in yaw (generates no motion parallax).We found that adding simulated angular or linear head oscillation to radial flow increased the strength of linear vection in depth. Neither type …
Influence Of Head Orientation And Viewpoint Oscillation On Linear Vection, Pearl S. Guterman, Robert S. Allison, Stephen Palmisano, James E. Zacher
Influence Of Head Orientation And Viewpoint Oscillation On Linear Vection, Pearl S. Guterman, Robert S. Allison, Stephen Palmisano, James E. Zacher
Faculty of Health and Behavioural Sciences - Papers (Archive)
Sensory conRict !.heories predict thai adding simulatcd viewpoint oscillUlion to sclf-motion displays should generate significant and sustained visual-vestibul ar conniet and reduce !.he likelihood of itlusory self· motion (vccl ion). However. research sh.ows th.at viewpoinl oscillation enhances vectioil in uprigh.t observers. This study examined whclh.cr the oscil lation advantage for veclion depends on head orientalion with respect to gravily. Displays that simulated forwardlbackward self-motion wi th/Without horizontal and vertical viewpoint oscillation were presented to observers in uprigh.t (sealed and standing) and lying (supine. prone. and len side down) body postures. Viewpoint oscillation was found to enhance vection for 0111 oflhe …
Perceived Display Speed Helps Account For The 'Jitter Advantage' In Vection, D Apthorp, S Palmisano
Perceived Display Speed Helps Account For The 'Jitter Advantage' In Vection, D Apthorp, S Palmisano
Faculty of Health and Behavioural Sciences - Papers (Archive)
Illusions of self-motion in depth ('vection') are strongly enhanced when coherent viewpoint oscillation or jitter is added to the inducing optic flow displays (Palmisano et al, 2010 Perception2957-67). The underlying cause of this "jitter advantage" is still unknown. Here we investigate the possibility that perceived speed plays a role, since other manipulations that increase perceived speed (adding stereo, using contracting rather than expanding flow) also increase vection in depth, and reducing perceived speed reduces vection. First, in a 2AFC procedure, we measured PSEs for smooth and vertically oscillating motion-in-depth displays; oscillating displays were uniformly perceived as faster. Then we used …
Directionless Vection: A New Illusory Self-Motion Perception, Takeharu Seno, Y Yamada, Stephen A. Palmisano
Directionless Vection: A New Illusory Self-Motion Perception, Takeharu Seno, Y Yamada, Stephen A. Palmisano
Faculty of Health and Behavioural Sciences - Papers (Archive)
We report a new visual illusion, "directionless vection." When expanding and contracting optic flows are simultaneously presented in the same depth plane, observers can perceive illusory self-motion (vection) without direction
Hunger Enhances Vertical Vection, Takeharu Seno, Hiroyuki Ito, Shoji Sunaga, Stephen Palmisano
Hunger Enhances Vertical Vection, Takeharu Seno, Hiroyuki Ito, Shoji Sunaga, Stephen Palmisano
Faculty of Health and Behavioural Sciences - Papers (Archive)
Hunger was found to facilitate visually induced illusory upward and downward self-motions (vertical vection), but not illusory self-motion in depth (vection in depth). We propose that the origin of this hunger effect lies in the possibility that vertical self-motions (both real and illusory) are more likely to induce changes in visceral state.
Horizontal Fixation Point Oscillation And Simulated Viewpoint Oscillation Both Increase Vection In Depth, Stephen Palmisano, Juno Kim, Tom C. A Freeman
Horizontal Fixation Point Oscillation And Simulated Viewpoint Oscillation Both Increase Vection In Depth, Stephen Palmisano, Juno Kim, Tom C. A Freeman
Faculty of Health and Behavioural Sciences - Papers (Archive)
Previous research has shown that vection can be enhanced by adding horizontal simulated viewpoint oscillation to radial flow. Adding a horizontally oscillating fixation target to purely radial flow induces a superficially similar illusion of self-motion, where the observer's perceived heading oscillates left and right as their eyes pursue the moving target. This study directly compared the vection induced by these two conditions for the first time. Adding fixation point oscillation and simulated viewpoint oscillation to radial flow were both found to improve vection (relative to no oscillation control displays). Neither vection advantage could be explained in terms of differences in …
Vection Can Be Induced Without Global-Motion Awareness, Takeharu Seno, Stephen A. Palmisano, Hiroyuki Ito, Shoji Sunaga
Vection Can Be Induced Without Global-Motion Awareness, Takeharu Seno, Stephen A. Palmisano, Hiroyuki Ito, Shoji Sunaga
Faculty of Health and Behavioural Sciences - Papers (Archive)
A new vection illusion is reported. Vection was induced even though there was no consciously perceived global display motion corresponding to the self-motion. The resulting experience can be summarised as: ``I feel that I am moving but I do not know why''.
Simulated Viewpoint Jitter Shakes Sensory Conflict Accounts Of Vection, Stephen A. Palmisano, Robert S Allison, Juno Kim, Frederick Bonato
Simulated Viewpoint Jitter Shakes Sensory Conflict Accounts Of Vection, Stephen A. Palmisano, Robert S Allison, Juno Kim, Frederick Bonato
Faculty of Health and Behavioural Sciences - Papers (Archive)
Sensory conflict has been used to explain the way we perceive and control our self-motion, as well as the aetiology of motion sickness. However, recent research on simulated viewpoint jitter provides a strong challenge to one core prediction of these theories — that increasing sensory conflict should always impair visually induced illusions of self-motion (known as vection). These studies show that jittering self-motion displays (thought to generate significant and sustained visual–vestibular conflict) actually induce superior vection to comparable non-jittering displays (thought to generate only minimal/transient sensory conflict). Here we review viewpoint jitter effects on vection, postural sway, eye-movements and motion …
Effects Of Gaze On Vection From Jittering, Oscillating, And Purely Radial Optic Flow, Stephen A. Palmisano, Juno Kim
Effects Of Gaze On Vection From Jittering, Oscillating, And Purely Radial Optic Flow, Stephen A. Palmisano, Juno Kim
Faculty of Health and Behavioural Sciences - Papers (Archive)
In this study, we examined the effects of different gaze types (stationary fixation, directed looking, or gaze shifting) and gaze eccentricities (central or peripheral) on the vection induced by jittering, oscillating, and purely radial optic flow. Contrary to proposals of eccentricity independence for vection (e.g., Post, 1988), we found that peripheral directed looking improved vection and peripheral stationary fixation impaired vection induced by purely radial flow (relative to central gaze). Adding simulated horizontal or vertical viewpoint oscillation to radial flow always improved vection, irrespective of whether instructions were to fixate, or look at, the center or periphery of the self-motion …
Vection Change Exacerbates Simulator Sickness In Virtual Environments, Frederick Bonato, Andrea Bubka, Stephen A. Palmisano, Danielle Phillip, Giselle Moreno
Vection Change Exacerbates Simulator Sickness In Virtual Environments, Frederick Bonato, Andrea Bubka, Stephen A. Palmisano, Danielle Phillip, Giselle Moreno
Faculty of Health and Behavioural Sciences - Papers (Archive)
The optic flow patterns generated by virtual reality (VR) systems typically produce visually induced experiences of self-motion (vection). While this vection can enhance presence in VR, it is often accompanied by a variant of motion sickness called simulator sickness (SS). However, not all vection experiences are the same. In terms of perceived heading and/or speed, visually simulated self-motion can be either steady or changing. It was hypothesized that changing vection would lead to more SS. Participants viewed an optic flow pattern that either steadily expanded or alternately expanded and contracted. In one experiment, SS was measured pretreatment and after 5 …
Expanding And Contracting Optic-Flow Patterns And Vection, Andrea Bubka, Frederick Bonato, Stephen A. Palmisano
Expanding And Contracting Optic-Flow Patterns And Vection, Andrea Bubka, Frederick Bonato, Stephen A. Palmisano
Faculty of Health and Behavioural Sciences - Papers (Archive)
When stationary observers view an optic-flow pattern, visually induced self-motion perception (vection) and a form of motion sickness known as simulator sickness (SS), can result. Previous results suggest that an expanding flow pattern leads to more SS than a contracting pattern. Sensory conflict, a possible cause of SS, may be more salient when an expanding optic-flow pattern is viewed. An experiment was conducted to test if a more salient sensory conflict accompanying expanding flow patterns might inhibit vection. Participants (n=15) viewed a pattern of blue squares, either steadily expanded or contracted, on a large rear-projection screen. Vection onset and magnitude …
Accelerating Self-Motion Displays Produce More Compelling Vection In Depth, Stephen A. Palmisano, Robert S Allison, Fiona Pekin
Accelerating Self-Motion Displays Produce More Compelling Vection In Depth, Stephen A. Palmisano, Robert S Allison, Fiona Pekin
Faculty of Health and Behavioural Sciences - Papers (Archive)
We examined the vection in depth induced when simulated random self-accelerations (jitter) and periodic self-accelerations (oscillation) were added to radial expanding optic flow (simulating constant-velocity forward self-motion). Contrary to the predictions of sensory-conflict theory frontal-plane jitter and oscillation were both found to significantly decrease the onsets and increase the speeds of vection in depth. Depth jitter and oscillation had lesser, but still significant, effects on the speed of vection in depth. A control experiment demonstrated that adding global perspective motion which simulated a constant-velocity frontal-plane self-motion had no significant effect on vection in depth induced by the radial component of …
Vertical Display Oscillation Effects On Forward Vection And Simulator Sickness, Stephen A. Palmisano, Andrea Bubka, Frederick Bonato, John Folder
Vertical Display Oscillation Effects On Forward Vection And Simulator Sickness, Stephen A. Palmisano, Andrea Bubka, Frederick Bonato, John Folder
Faculty of Health and Behavioural Sciences - Papers (Archive)
Background: The current study investigated the effects that vertical display oscillation had on the development of both vection and simulator sickness. Methods: Sixteen subjects were exposed to optic flow displays, which simulated either: (i) constant velocity forward self-motion (pure radial flow); or (ii) combined constant velocity forward and vertically oscillating self-motion (radial flow with vertical oscillation at one of three frequencies: 1.8, 3.7 or 7.4 Hz). During each 10-min display exposure, subjects rated the strength of their vection and 8 symptoms listed on the Subjective Symptoms of Motion Sickness (SSMS) scale at 2-min intervals. Subjects also completed the Simulator Sickness …
Jitter And Size Effects On Vection Are Immune To Experimental Instructions And Demands, Stephen A. Palmisano, Amy Y. Chan
Jitter And Size Effects On Vection Are Immune To Experimental Instructions And Demands, Stephen A. Palmisano, Amy Y. Chan
Faculty of Health and Behavioural Sciences - Papers (Archive)
Both coherent perspective jitter and explicit changing-size cues have been shown to improve the vection induced by radially expanding optic flow. The current study examined whether these stimulus-based vection advantages could be modified by altering cognitions/expectations about both the likelihood of self-motion perception and the purpose of the experiment. In the main experiment, participants were randomly assigned into two groups – one where the cognitive conditions biased participants towards self-motion perception and another where the cognitive conditions biased them towards object motion perception. Contrary to earlier findings by Lepecq et al (1995), we found that identical visual displays were less …
Consistent Stereoscopic Information Increases The Perceived Speed Of Vection In Depth, Stephen A. Palmisano
Consistent Stereoscopic Information Increases The Perceived Speed Of Vection In Depth, Stephen A. Palmisano
Faculty of Health and Behavioural Sciences - Papers (Archive)
Previous research found that adding stereoscopic information to radially expanding optic flow decreased vection onsets and increased vection durations (Palmisano S, 1996 Perception & Psychophysics 58 1168-1176). In the current experiments, stereoscopic cues were also found to increase perceptions of egospeed and self-displacement during vection in depth - but only when these cues were consistent with monocularly-available information about self-motion. Stereoscopic information did not appear to be improving vection by increasing the perceived maximum extent of displays or by making displays appear more three-dimensional. Rather, it appeared that consistent patterns of stereoscopic optic flow provided extra, purely binocular information about …
Global-Perspective Jitter Improves Vection In Central Vision, Stephen A. Palmisano, Barbara Gillam, Shane Blackburn
Global-Perspective Jitter Improves Vection In Central Vision, Stephen A. Palmisano, Barbara Gillam, Shane Blackburn
Faculty of Health and Behavioural Sciences - Papers (Archive)
Previous vection research has tended to minimise visual - vestibular conflict by using optic-flow patterns which simulate self-motions of constant velocity. Here, experiments are reported on the effect of adding 'global-perspective jitter' to these displays -- simulating forward motion of the observer on a platform oscillating in horizontal and/or vertical dimensions. Unlike non-jittering displays, jittering displays produced a situation of sustained visual - vestibular conflict. Contrary to the prevailing notion that visual - vestibular conflict impairs vection, jittering optic flow was found to produce shorter vection onsets and longer vection durations than non-jittering optic flow for all of jitter magnitudes …
Stimulus Eccentricity And Spatial Frequency Interact To Determine Circular Vection, Stephen A. Palmisano, Barbara Gillam
Stimulus Eccentricity And Spatial Frequency Interact To Determine Circular Vection, Stephen A. Palmisano, Barbara Gillam
Faculty of Health and Behavioural Sciences - Papers (Archive)
While early research suggested that peripheral vision dominates the perception of selfmotion, subsequent studies found little or no effect of stimulus eccentricity. In contradiction to these broad notions of 'peripheral dominance' and 'eccentricity independence', the present experiments showed that the spatial frequency of optic flow interacts with its eccentricity to determine circular vection magnitude—central stimulation producing the most compelling vection for high-spatial-frequency stimuli and peripheral stimulation producing the most compelling vection for lower-spatial-frequency stimuli. This interaction appeared to be due, in part at least, to the effect that the higher-spatial-frequency moving pattern had on subjects' ability to organise optic flow …