ORCID Profile
0000-0002-9140-5681
Current Organisation
University of Wollongong
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In Research Link Australia (RLA), "Research Topics" refer to ANZSRC FOR and SEO codes. These topics are either sourced from ANZSRC FOR and SEO codes listed in researchers' related grants or generated by a large language model (LLM) based on their publications.
Psychology | Sensory Processes, Perception And Performance | Sensory Processes, Perception and Performance | Virtual Reality and Related Simulation | Transport Engineering | Sensory processes perception and performance | Autonomous Vehicles | Mechanical Engineering | Virtual and mixed reality | Computer-Human Interaction
Behavioural and cognitive sciences | Expanding Knowledge in Psychology and Cognitive Sciences | Road Safety | Application Tools and System Utilities | Computer Gaming Software | Automotive Equipment | Air transport | Expanding Knowledge in Technology |
Publisher: Springer Science and Business Media LLC
Date: 16-09-2021
Publisher: SAGE Publications
Date: 08-2004
DOI: 10.1068/P5242
Abstract: Both coherent perspective jitter and explicit changing-size cues have been shown to improve the vection induced by radially expanding optic flow. We examined whether these stimulus-based vection advantages could be modified by altering cognitions and/or 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 Perception24 435–449), we found that identical visual displays were less likely to induce vection in ‘object-motion-bias’ conditions than in ‘self-motion bias’ conditions. However, significant jitter and size advantages for vection were still found in both cognitive conditions (cognitive bias effects were greatest for non-jittering same-size control displays). The current results suggest that if a sufficiently large vection advantage can be produced when participants are expecting to experience self-motion, it is likely to persist in object-motion-bias conditions.
Publisher: Elsevier BV
Date: 2006
DOI: 10.1016/J.VISRES.2005.10.005
Abstract: Three experiments examined the effects of image decorrelation on the stereoscopic detection of sinusoidal depth gratings in static and dynamic random-dot stereograms (RDS). Detection was found to tolerate greater levels of image decorrelation as: (i) density increased from 23 to 676 dots/deg2 (ii) spatial frequency decreased from 0.88 to 0.22 cpd (iii) litude increased above 0.5 arcmin and (iv) dot lifetime decreased from 1.6s (static RDS) to 80 ms (dynamic RDS). In each case, the specific pattern of tolerance to decorrelation could be explained by its consequences for image s ling, filtering, and the influence of depth noise.
Publisher: Association for Research in Vision and Ophthalmology (ARVO)
Date: 09-10-2014
DOI: 10.1167/14.12.5
Abstract: Compelling illusions of self-motion, known as vection, can be produced in a stationary observer by visual stimulation alone. The role of binocular vision and stereopsis in these illusions was explored in a series of three experiments. Previous research had provided evidence of stereoscopic enhancements for linear vection in depth (e.g., Palmisano, 1996, 2002). Here we examined for the first time the effects of binocular vision and stereopsis on linear vertical vection. Vertical vection was induced by the upward or downward translation of large stereoscopic surfaces. These surfaces were horizontally oriented depth corrugations produced by disparity modulation of patterns of persistent or short lifetime dot elements. We found that binocular viewing of such surfaces significantly increased the magnitudes and decreased the onset delays of vertical vection. Experiments utilizing short lifetime dot stereograms demonstrated that these particular binocular enhancements of vection were due to the motion of stereoscopically defined features.
Publisher: Springer Science and Business Media LLC
Date: 18-09-2022
Publisher: Association for Research in Vision and Ophthalmology (ARVO)
Date: 26-11-2012
DOI: 10.1167/12.12.15
Abstract: 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 perceived scene rigidity or motion adaptation. Our findings also provided little support for the notion that pursuit eye-movements were essential for the simulated viewpoint oscillation advantage for vection (since observers successfully fixated a stationary, centrally- placed target during these conditions in the current experiments). The strongest support was found for the proposal that fixation point oscillation and simulated viewpoint oscillation both improve vection by increasing the observer's global retinal motion.
Publisher: Informa UK Limited
Date: 19-03-2008
Publisher: Elsevier BV
Date: 12-2019
Publisher: SAGE Publications
Date: 2008
DOI: 10.1068/P5806
Abstract: 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 the optic flow. These results are incompatible with the notion that constant-velocity displays produce optimal vection. Rather, they indicate that displays simulating self-acceleration can often produce more compelling experiences of self-motion in depth.
Publisher: Public Library of Science (PLoS)
Date: 23-05-2018
Publisher: SAGE Publications
Date: 2003
DOI: 10.1068/P3468
Abstract: Palmisano et al (2000 Perception29 57–67) found that adding coherent perspective jitter to constant-velocity radial flow improved visually induced illusions of self-motion (vection). This was a surprising finding, because unlike pure radial flow, this jittering radial flow should have generated sustained visual–vestibular conflicts—previously thought to always reduce/impair vection. We attempted to ascertain the essential stimulus features for this jitter advantage for vection by examining three novel types of jitter display. While adding incoherent jitter to radial flow was found to impair vection, adding coherent non-perspective jitter had little effect on this subjective experience (contrary to the notion that jitter improves vection by reducing adaptation to radial flow). Importantly, we found that coherent perspective jitter not only improves the vection induced by radial flow, but it also appears to induce modest vection by itself (demonstrating that vection can still occur when there is an extreme mismatch between actual and expected vestibular activity). These results suggest that the previously demonstrated advantage for coherent perspective jitter was due (in part at least) to jittering vection combining with forwards vection in depth to produce a more compelling overall vection experience.
Publisher: Brill
Date: 2017
DOI: 10.1163/22134808-00002593
Abstract: Behavioural studies have consistently found stronger vection responses for oscillating, compared to smooth/constant, patterns of radial flow (the simulated viewpoint oscillation advantage for vection). Traditional accounts predict that simulated viewpoint oscillation should impair vection by increasing visual–vestibular conflicts in stationary observers (as this visual oscillation simulates self-accelerations that should strongly stimulate the vestibular apparatus). However, support for increased vestibular activity during accelerating vection has been mixed in the brain imaging literature. This fMRI study examined BOLD activity in visual (cingulate sulcus visual area — CSv medial temporal complex — MT+ V6 precuneus motion area — PcM) and vestibular regions (parieto-insular vestibular cortex — PIVC osterior insular cortex — PIC ventral intraparietal region — VIP) when stationary observers were exposed to vection-inducing optic flow (i.e., globally coherent oscillating and smooth self-motion displays) as well as two suitable control displays. In line with earlier studies in which no vection occurred, CSv and PIVC/PIC both showed significantly increased BOLD activity during oscillating global motion compared to the other motion conditions (although this effect was found for fewer subjects in PIVC/PIC). The increase in BOLD activity in PIVC/PIC during prolonged exposure to the oscillating (compared to smooth) patterns of global optical flow appears consistent with vestibular facilitation.
Publisher: Springer Science and Business Media LLC
Date: 22-01-2014
DOI: 10.1007/S00221-014-3835-Y
Abstract: This study asked whether in idual differences in the influence of vision on postural stability could be used to predict the strength of subsequently induced visual illusions of self-motion (vection). In the experiment, we first measured spontaneous postural sway while subjects stood erect for 60 s with their eyes both open and both closed. We then showed our subjects two types of self-motion display: radially expanding optic flow (simulating constant velocity forwards self-motion) and vertically oscillating radially expanding optic flow (simulating constant velocity forwards self-motion combined with vertical head oscillation). As expected, subjects swayed more with their eyes closed (compared to open) and experienced more compelling illusions of self-motion with vertically oscillating (as opposed to smooth) radial flow. The extent to which participants relied on vision for postural stability-measured as the ratio of sway with eyes closed compared to that with eyes open-was found to predict vection strength. However, this was only the case for displays representing smooth self-motion. It seems that for oscillating displays, other factors, such as visual-vestibular interactions, may be more important.
Publisher: Springer Science and Business Media LLC
Date: 02-11-2020
Publisher: Frontiers Media SA
Date: 11-11-2014
Publisher: Frontiers Media SA
Date: 26-02-2021
DOI: 10.3389/FRVIR.2021.627333
Abstract: This paper discusses results from two successive rounds of virtual mines rescue training. The first round was conducted in a surround projection environment (360-VR), and the second round was conducted in desktop virtual reality (Desktop-VR). In the 360-VR condition, trainees participated as groups, making collective decisions. In the Desktop-VR condition, trainees could control their avatars in idually. Overall, 372 participants took part in this study, including 284 mines rescuers who took part in 360-VR, and 243 in Desktop-VR. (155 rescuers experienced both.) Each rescuer who trained in 360-VR completed a battery of pre- and post-training questionnaires. Those who attended the Desktop-VR session only completed the post-training questionnaire. We performed principal components analysis on the questionnaire data, followed by a multiple regression analysis, the results of which suggest that the chief factor contributing to positive learning outcome was Learning Context, which extracted information about the quality of the learning content, the trainers, and their feedback. Subjective feedback from the Desktop-VR participants indicated that they preferred Desktop-VR to 360-VR for this training activity, which highlights the importance of choosing an appropriate platform for training applications, and links back to the importance of Learning Context. Overall, we conclude the following: 1) it is possible to train effectively using a variety of technologies but technology that is well-suited to the training task is more useful than technology that is “more advanced,” and 2) factors that have always been important in training, such as the quality of human trainers, remain critical for virtual reality training.
Publisher: SAGE Publications
Date: 09-2007
DOI: 10.1068/P5637
Abstract: Previous research into the effects of viewpoint change on face recognition has typically dealt with rotations around the head's vertical axis (yaw). Another common, although less studied, source of viewpoint variation in faces is rotation around the head's horizontal pitch axis (pitch). In the current study we used both a sequential matching task and an old/new recognition task to examine the effect of viewpoint change following rotation about both pitch and yaw axes on human face recognition. The results of both tasks showed that recognition performance was better for faces rotated about yaw compared to pitch. Further, recognition performance for faces rotated upwards on the pitch axis was better than for faces rotated downwards. Thus, equivalent angular rotations about pitch and yaw do not produce equivalent viewpoint-dependent declines in recognition performance.
Publisher: Springer Science and Business Media LLC
Date: 05-2010
DOI: 10.3758/APP.72.4.999
Publisher: Springer Science and Business Media LLC
Date: 12-08-2021
Publisher: SAGE Publications
Date: 2000
DOI: 10.1068/P2990
Abstract: 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 and temporal frequencies examined. On the basis of these findings, it would appear that purely radial patterns of optic flow are not the optimal inducing stimuli for vection. Rather, flow patterns which contain both regular and random-oscillating components appear to produce the most compelling subjective experiences of self-motion.
Publisher: Public Library of Science (PLoS)
Date: 20-03-2014
Publisher: Brill
Date: 2013
DOI: 10.1163/22134808-00002402
Abstract: Visually induced illusory self-motion (vection) was facilitated by active breaststroke arm and body movements. Optic flow was generated by having the standing observer make these arm movements, which were detected by Kinect and incorporated into the display. When generated, this optic flow was either expanding (i.e. congruent with the observer’s head motion) or contracting (i.e. incongruent with his/her head motion). Optic flow generated during these active movement conditions was also later played back to the observer during passive viewing conditions. On each of these trials, we recorded vection strength (latency, duration and magnitude). We found that: (i) both congruent and incongruent breaststroke movements increased vection (i.e. compared to passive viewing conditions) and (ii) congruent breaststroke movements increased vection more than incongruent ones. We name the enhancement provided by this type of active movement ‘virtual swimming’. This demonstration shows that even unusual body movements can function as a self-motion signal.
Publisher: SAGE Publications
Date: 2012
DOI: 10.1068/I0518SAS
Abstract: 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.
Publisher: American Psychological Association (APA)
Date: 2008
DOI: 10.1037/A0012659
Abstract: This study examined three visual strategies for timing the initiation of the landing flare based on perceptions of either: (a) a critical height above ground level (b) a critical runway width angle (Psi) or (c) a critical time-to-contact (TTC) with the runway. Visual displays simulated landing approaches with trial-to-trial variations in glideslope, lighting, and scene detail. Twenty-four participants (8 private pilots, 8 student pilots, and 8 nonpilots) were instructed to initiate the flare when they perceived that their TTC with the runway (30 m wide by 840 m long) had reached a critical value of 2 seconds. Our results demonstrated a significant effect of flight experience on flare timing accuracy and dominance of the height-based strategy over the runway-width-angle and TTC-based strategies.
Publisher: Elsevier BV
Date: 12-2008
DOI: 10.1016/J.BRAINRESBULL.2008.09.011
Abstract: Recent studies have shown that the vection in depth experienced by stationary observers viewing constant velocity radial flow can be enhanced by adding simulated viewpoint jitter/oscillation. This study examined the effect of manipulating visual-vestibular conflict on the perceived strength and speed of vection in depth. Four conditions were examined: (i) radial flow without viewpoint jitter viewed by stationary observers (consistent visual-vestibular inputs) (ii) radial flow with viewpoint jitter synchronized to lateral head oscillation (consistent inputs) (iii) radial flow with viewpoint jitter viewed by stationary observers (inconsistent inputs) (iv) radial flow without viewpoint jitter viewed during head oscillation (inconsistent inputs). We found that the strength and perceived speed of vection in depth was always greater when simulated viewpoint jitter was introduced. No further vection enhancement was found when this jitter was generated by active head oscillation-even though passive jitter conditions should have generated significant sensory conflicts, whereas active jitter conditions would not. Active head oscillation without display jitter also had little effect, producing similar vection strength/speed ratings to stationary observation of non-jittering optic flow. Horizontal eye tracking suggested that retinal stimulation was similar between comparable active and passive viewing conditions. This stabilization of the retinal image across active and passive conditions appeared to be due to cooperative engagement of the translational vestibuloocular reflex and the visually driven ocular following response. Rather than providing evidence for synergistic integration of self-motion perception, these findings obtained with low-frequency sensory stimuli suggest that self-motion perception is dominated by visual processing centres.
Publisher: SAGE Publications
Date: 04-2018
Publisher: Springer International Publishing
Date: 2017
Publisher: Association for Research in Vision and Ophthalmology (ARVO)
Date: 07-10-2010
DOI: 10.1167/10.12.7
Abstract: This study examined the role of eccentric gaze dynamics in the generation of visual illusions of self-motion (i.e., vection). In Experiment 1, observers maintained their gaze either upward, downward, leftward, or rightward with respect to the center of a radially expanding optic flow pattern, which simulated forward self-motion in depth through a 3D cloud of objects. Real-time vection strength ratings and changes in horizontal and vertical eye positions were recorded simultaneously. Vection strength was found to increase progressively over the course of each 30-s presentation of radial flow. Eye tracking revealed strong optokinetic responses, consistent with ocular following responses (OFRs). Reported increases in vection strength in all four gaze conditions were typically preceded by reductions in slow-phase eye velocity. Similar results were found in Experiment 2, where displays simulated self-motion over a ground plane, which provided superior perspective. We conclude in both cases that enhancements of vection strength over time were temporally contingent upon the changing character of OFR while viewing these displays.
Publisher: Elsevier BV
Date: 04-2020
Publisher: Elsevier BV
Date: 04-2002
Publisher: SAGE Publications
Date: 04-2002
DOI: 10.1068/P3321
Abstract: Previous research found that adding stereoscopic information to radially expanding optic flow decreased vection onsets and increased vection durations (Palmisano, 1996 Perception & Psychophysics58 1168–1176). In the current experiments, stereoscopic cues were also found to increase perceptions of vection speed 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 vection speed, which resulted in faster/more compelling illusions of self-motion in depth.
Publisher: SAGE Publications
Date: 2012
DOI: 10.1068/P7246
Abstract: We measured the strength of the hollow-face illusion—the ‘flipping distance’ at which perception changes between convex and concave—as a function of a lens-induced 3 dioptre refractive error and monocular/binocular viewing. Refractive error and closing one eye both strengthened the illusion to approximately the same extent. The illusion was weakest viewed binocularly without refractive error and strongest viewed monocularly with it. This suggests binocular cues disambiguate the illusion at greater distances than monocular cues, but that both are disrupted by refractive error. We argue that refractive error leaves the ambiguous low-spatial-frequency shading information critical to the illusion largely unaffected while disrupting other, potentially disambiguating, depth/distance cues.
Publisher: Springer Science and Business Media LLC
Date: 07-03-2016
DOI: 10.3758/S13414-016-1076-9
Abstract: Optic flow provides important information for the perception of self-motion and can be generated by both diffuse and specular reflectance. Previous self-motion research using virtual environments has primarily considered the properties of diffuse optic flow, but not of specular flow. We used graphical simulations to examine the extent to which visually induced self-motion (vection) is robust against the variations in optic flow generated by different surface optics. We found that specular flow alone was capable of generating vection that was equivalent in strength to that generated by diffuse flow (Exp. 1). To test whether this specularly induced vection depends on midlevel visual processing, we measured vection strengths under conditions in which the luminance polarity of specular highlights was inverted. We found that inverting the luminance of specular reflections impaired vection strength, as compared with the vection generated by conditions with ecologically correct diffuse and/or specular flow (Exp. 2). We also found these variations in vection strength were correlated with the perceived relief heights of the surfaces depicted in the image sequences. These findings together suggest that vection can be induced by pure specular flow and that it requires processing beyond the computation of retinal motion velocities-most likely, processes involved in the recovery of 3-D surface shape.
Publisher: Springer Science and Business Media LLC
Date: 11-11-2019
DOI: 10.1007/S00221-019-05674-0
Abstract: This study examined the contributions of low-, mid- and high-level visual motion information to vection. We compared the vection experiences induced by hand-drawn and computer-generated animation clips to those induced by versions of these movies that contained only their pure optic flow. While the original movies were found to induce longer and stronger vection experiences than the pure optic flow, vection onsets were not significantly altered by removing the mid- and high-level information. We conclude that low-level visual motion information appears to be important for vection induction, whereas mid- and higher-level display information appears to be important for sustaining and strengthening this vection after its initial induction.
Publisher: Brill
Date: 2012
Publisher: Association for Research in Vision and Ophthalmology (ARVO)
Date: 11-2009
DOI: 10.1167/9.12.1
Publisher: SAGE Publications
Date: 07-2016
Abstract: Adding simulated viewpoint jitter or oscillation to displays enhances visually induced illusions of self-motion (vection). The cause of this enhancement is yet to be fully understood. Here, we conducted psychophysical experiments to investigate the effects of different types of simulated oscillation on vertical vection. Observers viewed horizontally oscillating and nonoscillating optic flow fields simulating downward self-motion through an aperture. The aperture was visually simulated to be nearer to the observer and was stationary or oscillating in-phase or counter-phase to the direction of background horizontal oscillations of optic flow. Results showed that vection strength was modulated by the oscillation of the aperture relative to the background optic flow. Vertical vection strength increased as the relative oscillatory horizontal motion between the flow and the aperture increased. However, such increases in vection were only generated when the added oscillations were orthogonal to the principal direction of the optic flow pattern, and not when they occurred in the same direction. The oscillation effects observed in this investigation could not be explained by motion adaptation or different (motion parallax based) effects on depth perception. Instead, these results suggest that the oscillation advantage for vection depends on relative visual motion.
Publisher: Springer Science and Business Media LLC
Date: 08-1996
DOI: 10.3758/BF03207550
Abstract: During self-motions, different patterns of optic flow are presented to the left and right eyes. Previous research has, however, focused mainly on the self-motion information contained in a single pattern of optic flow. The present experiments investigated the role that binocular disparity plays in the visual perception of self-motion, showing that the addition of stereoscopic cues to optic flow significantly improves forward linear vection in central vision. Improvements were also achieved by adding changing-size cues to sparse (but not dense) flow patterns. These findings showed that assumptions in the heading literature that stereoscopic cues facilitate self-motion only when the optic flow has ambiguous depth ordering do not apply to vection. Rather, it was concluded that both stereoscopic and changing-size cues provide additional motion-in-depth information that is used in perceiving self-motion.
Publisher: Springer Science and Business Media LLC
Date: 11-2009
Publisher: Elsevier BV
Date: 2017
Publisher: Springer Science and Business Media LLC
Date: 25-07-2017
DOI: 10.1007/S00221-017-5033-1
Abstract: Sounds are thought to contribute to the perceptions of self-motion, often via higher-level, cognitive mechanisms. This study examined whether illusory self-motion (i.e. vection) could be induced by auditory metaphorical motion stimulation (without providing any spatialized or low-level sensory information consistent with self-motion). Five different types of auditory stimuli were presented in mono to our 20 blindfolded, stationary participants (via a loud speaker array): (1) an ascending Shepard-Risset glissando (2) a descending Shepard-Risset glissando (3) a combined Shepard-Risset glissando (4) a combined-adjusted (loudness-controlled) Shepard-Risset glissando and (5) a white-noise control stimulus. We found that auditory vection was consistently induced by all four Shepard-Risset glissandi compared to the white-noise control. This metaphorical auditory vection appeared similar in strength to the vection induced by the visual reference stimulus simulating vertical self-motion. Replicating past visual vection findings, we also found that in idual differences in postural instability appeared to significantly predict auditory vection strength ratings. These findings are consistent with the notion that auditory contributions to self-motion perception may be predominantly due to higher-level cognitive factors.
Publisher: SPIE
Date: 27-04-2007
DOI: 10.1117/12.719892
Publisher: Public Library of Science (PLoS)
Date: 02-12-2014
Publisher: Springer New York
Date: 2010
Publisher: ACM
Date: 12-11-2019
Publisher: MIT Press - Journals
Date: 06-2008
Abstract: 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 min of viewing using the Simulator Sickness Questionnaire. In a second experiment employing the same stimuli, vection onset and magnitude were measured using a computer-interfaced slide indicator. The steadily expanding flow pattern, compared to the expanding and contracting pattern, led to: 1) significantly less SS, 2) lower subscores for nausea, oculomotor, and disorientation symptoms, 3) more overall vection magnitude, and 4) less changing vection. Collectively, these results suggest that changing vection exacerbates SS.
Publisher: Public Library of Science (PLoS)
Date: 28-12-2018
Publisher: Brill
Date: 2011
Abstract: 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 sickness, and relate them to recent behavioural and neurophysiological findings. It is shown that jitter research provides important insights into the role that sensory interaction plays in self-motion perception.
Publisher: SAGE Publications
Date: 2013
DOI: 10.1068/P7511
Abstract: Ilusory self-motion (vection) can be induced by large areas of visual motion stimulation. Here we demonstrate for the first time that illusory expansion can induce vection in the absence of any physical display motion.
Publisher: SAGE Publications
Date: 2012
DOI: 10.1068/P7226
Abstract: 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.
Publisher: Springer Science and Business Media LLC
Date: 19-12-2022
Publisher: Springer Science and Business Media LLC
Date: 02-10-2012
DOI: 10.1007/S00221-012-3275-5
Abstract: Successful adaptation to the microgravity environment of space and readaptation to gravity on earth requires recalibration of visual and vestibular signals. Recently, we have shown that adding simulated viewpoint oscillation to visual self-motion displays produces more compelling vection (despite the expected increase in visual-vestibular conflict experienced by stationary observers). Currently, it is unclear what role adaptation to gravity might play in this oscillation-based vection advantage. The vection elicited by optic flow displays simulating either smooth forward motion or forward motion perturbed by viewpoint oscillation was assessed before, during and after microgravity exposure in parabolic flight. During normal 1-g conditions subjects experienced significantly stronger vection for oscillating compared to smooth radial optic flow. The magnitude of this oscillation enhancement was reduced during short-term microgravity exposure, more so for simulated interaural (as opposed to spinal) axis viewpoint oscillation. We also noted a small overall reduction in vection sensitivity post-flight. A supplementary experiment found that 1-g vection responses did not vary significantly across multiple testing sessions. These findings: (i) demonstrate that the oscillation advantage for vection is very stable and repeatable during 1-g conditions and (ii) imply that adaptation or conditioned responses played a role in the post-flight vection reductions. The effects observed in microgravity are discussed in terms of the ecology of terrestrial locomotion and the nature of movement in microgravity.
Publisher: SAGE Publications
Date: 09-1998
DOI: 10.1068/P271067
Abstract: While early research suggested that peripheral vision dominates the perception of self-motion, 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 into related motion about a single axis. For ex le, far-peripheral exposure to this high-spatial-frequency pattern caused many subjects to organise the optic flow into independent local regions of motion (a situation which clearly favoured the perception of object motion not self-motion). It is concluded that both high-spatial-frequency and low-spatial-frequency mechanisms are involved in the visual perception of self-motion—with their activities depending on the nature and eccentricity of the motion stimulation.
Publisher: Brill
Date: 09-2022
DOI: 10.1163/22134808-BJA10081
Abstract: This study investigated claims of disrupted equilibrium when listening to the Shepard–Risset glissando (which creates an auditory illusion of perpetually ascending/descending pitch). During each trial, 23 participants stood quietly on a force plate for 90 s with their eyes either open or closed (30 s pre-sound, 30 s of sound and 30 s post-sound). Their centre of foot pressure (CoP) was continuously recorded during the trial and a verbal measure of illusory self-motion (i.e., vection) was obtained directly afterwards. As expected, vection was stronger during Shepard–Risset glissandi than during white noise or phase-scrambled auditory control stimuli. In idual differences in auditorily evoked postural sway (observed during sound) were also found to predict the strength of this vection. Importantly, the patterns of sway induced by Shepard–Risset glissandi differed significantly from those during our auditory control stimuli — but only in terms of their temporal dynamics. Since significant sound type differences were not seen in terms of sway magnitude, this stresses the importance of investigating the temporal dynamics of sound–posture interactions.
Publisher: Aerospace Medical Association
Date: 11-2009
Abstract: Stationary subjects who perceive visually induced illusions of self-motion, or vection, in virtual reality (VR) often experience cybersickness, the symptoms of which are similar to those experienced during motion sickness. An experiment was conducted to test the effects of single and dual-axis rotation of a virtual environment on cybersickness. It was predicted that VR displays which induced illusory dual-axis (as opposed to single-axis) self-rotations in stationary subjects would generate more sensory conflict and subsequently more cybersickness. There were 19 in iduals (5 men, 14 women, mean age = 19.8 yr) who viewed the interior of a virtual cube that steadily rotated (at 60 degrees x s(-1)) about either the pitch axis or both the pitch and roll axes simultaneously. Subjects completed the Simulator Sickness Questionnaire (SSQ) before a trial and after 5 min of stimulus viewing. Post-treatment total SSQ scores and subscores for nausea, oculomotor, and disorientation were significantly higher in the dual-axis condition. These results support the hypothesis that a vection-inducing VR stimulus that rotates about two axes generates more cybersickness compared to aVR stimulus that rotates about only one. In the single-axis condition, sensory conflict and pseudo-Coriolis effects may have led to symptoms. However, in the dual-axis condition, not only was perceived self-motion more complex (two axes compared to one), the inducing stimulus was consistent with twice as much self-motion. Hence, the increased likelihood/magnitude of sensory conflict and pseudo-Coriolis effects may have subsequently resulted in a higher degree of cybersickness in the dual-axis condition.
Publisher: Frontiers Media SA
Date: 29-04-2021
DOI: 10.3389/FRVIR.2021.582156
Abstract: Humans rely on multiple senses to perceive their self-motion in the real world. For ex le, a sideways linear head translation can be sensed either by lamellar optic flow of the visual scene projected on the retina of the eye or by stimulation of vestibular hair cell receptors found in the otolith macula of the inner ear. Mismatches in visual and vestibular information can induce cybersickness during head-mounted display (HMD) based virtual reality (VR). In this pilot study, participants were immersed in a virtual environment using two recent consumer-grade HMDs: the Oculus Go (3DOF angular only head tracking) and the Oculus Quest (6DOF angular and linear head tracking). On each trial they generated horizontal linear head oscillations along the interaural axis at a rate of 0.5 Hz. This head movement should generate greater sensory conflict when viewing the virtual environment on the Oculus Go (compared to the Quest) due to the absence of linear tracking. We found that perceived scene instability always increased with the degree of linear visual-vestibular conflict. However, cybersickness was not experienced by 7/14 participants, but was experienced by the remaining participants in at least one of the stereoscopic viewing conditions (six of whom also reported cybersickness in monoscopic viewing conditions). No statistical difference in spatial presence was found across conditions, suggesting that participants could tolerate considerable scene instability while retaining the feeling of being there in the virtual environment. Levels of perceived scene instability, spatial presence and cybersickness were found to be similar between the Oculus Go and the Oculus Quest with linear tracking disabled. The limited effect of linear coupling on cybersickness, compared with its strong effect on perceived scene instability, suggests that perceived scene instability may not always be associated with cybersickness. However, perceived scene instability does appear to provide explanatory power over the cybersickness observed in stereoscopic viewing conditions.
Publisher: Elsevier BV
Date: 11-2001
DOI: 10.1016/S0042-6989(01)00183-3
Abstract: Stereoscopic corrugation detection in the presence of horizontal- and vertical- additive disparity noise was examined using a signal detection paradigm. Random-dot stereograms either represented a 3-D square-wave surface with various amounts of Gaussian-distributed additive disparity noise or had the same disparity values randomly redistributed. Stereoscopic detection of 2 arcmin peak litude corrugations was found to tolerate significantly greater litudes of vertical-disparity noise than horizontal-disparity noise--irrespective of whether the corrugations were horizontally or vertically oriented. However, this directional difference in tolerance to disparity noise was found to reverse when the corrugation and noise litudes were increased (so as to produce equivalent signal-to-noise ratios). These results suggest that horizontal- and vertical-disparity noise pose different problems for dot-matching and post-matching surface reconstruction as corrugation and noise litudes increase.
Publisher: ACM
Date: 12-11-2019
Publisher: Elsevier BV
Date: 11-2006
DOI: 10.1016/J.VISRES.2006.07.020
Abstract: We report a novel illusory distortion of the visual scene, which became apparent during both: (i) observer rotation inside a furnished stationary room and (ii) room rotation about the stationary observer. While this distortion had several manifestations, the most common experience was that scenery near fixation appeared to sometimes lead and other times lag more peripheral scenery. Across a series of experiments, we eliminated explanations based on eye-movements, distance misperception, peripheral aliasing, differential motion sensitivity and adaptation. We found that these illusory scene distortions occurred only when the observer perceived (real or illusory) changes in self-tilt and maintained a stable fixation.
Publisher: SAGE Publications
Date: 20-01-2016
Abstract: Interchanging the left and right eye views of a scene (pseudoscopic viewing) has been reported to produce vivid stereoscopic effects under certain conditions. In two separate field studies, we examined the experiences of 124 observers (76 in Study 1 and 48 in Study 2) while pseudoscopically viewing a distant natural outdoor scene. We found large in idual differences in both the nature and the timing of their pseudoscopic experiences. While some observers failed to notice anything unusual about the pseudoscopic scene, most experienced multiple pseudoscopic phenomena, including apparent scene depth reversals, apparent object shape reversals, apparent size and flatness changes, apparent reversals of border ownership, and even complex illusory foreground surfaces. When multiple effects were experienced, patterns of co-occurrence suggested possible causal relationships between apparent scene depth reversals and several other pseudoscopic phenomena. The latency for experiencing pseudoscopic phenomena was found to correlate significantly with observer visual acuity, but not stereoacuity, in both studies.
Publisher: SAGE Publications
Date: 2012
DOI: 10.1068/P7187
Abstract: Evidence suggests that experiencing the hollow-face illusion involves perceptual reversal of the binocular disparities associated with the face even though the rest of the scene appears unchanged. This suggests stereoscopic processing of object shape may be independent of scene-based processing of the layout of objects in depth. We investigated the effects of global scene-based and local object-based disparity on the compellingness of the perceived convexity of the face. We took stereoscopic photographs of people in scenes, and independently reversed the binocular disparities associated with the head and scene. Participants rated perceived convexity of a natural disparity (“convex”) or reversed disparity (“concave”) face shown either in its original context with reversed or natural disparities or against a black background. Faces with natural disparity were rated as more convincingly convex independent of the background, showing that the local disparities can affect perceived convexity independent of disparities across the rest of the image. However, the apparent convexity of the faces was also greater in natural disparity scenes compared to either a reversed disparity scene or a zero disparity black background. This independent effect of natural scene disparity suggests that the ‘solidity’ associated with natural scene disparities spread to enhance the perceived convexity of the face itself. Together, these findings suggest that global and local disparity exert independent and additive effects upon the perceived convexity of the face.
Publisher: Brill
Date: 07-2020
DOI: 10.1163/22134808-20191450
Abstract: We recently showed that auditory illusions of self-motion can be induced in the absence of physically accurate spatial cues (Mursic et al. , 2017). The current study was aimed at identifying which features of this auditory stimulus (the Shepard–Risset glissando) were responsible for this metaphorical auditory vection, as well as confirming anecdotal reports of motion sickness for this stimulus. Five different types of auditory stimuli were presented to 31 blindfolded, stationary participants through a loudspeaker array: (1) a descending Shepard–Risset glissando (2) a descending discrete Shepard scale (3) a descending sweep signal (4) a phase-scrambled version of (1) (auditory control type 1) and (5) white noise (auditory control type 2). We found that the auditory vection induced by the Shepard–Risset glissando was stronger than both types of auditory control, and the discrete Shepard scale stimulus. However, vection strength was not found to differ between the Shepard–Risset glissando and the sweep signal. This suggests that the continuous, gliding structure of both these auditory stimuli was integral to the induction of vection. Consistent with anecdotal reports that the Shepard–Risset glissando is also capable of generating motion sickness (as measured by the Fast Motion Sickness Scale and the Simulator Sickness Questionnaire), the likelihood and severity of sickness for these stimuli was found to increase with the strength of the auditory vection.
Publisher: Association for Research in Vision and Ophthalmology (ARVO)
Date: 24-06-2010
DOI: 10.1167/10.6.19
Abstract: There has been no direct examination of stereoscopic depth perception at very large observation distances and depths. We measured perceptions of depth magnitude at distances where it is frequently reported without evidence that stereopsis is non-functional. We adapted methods pioneered at distances up to 9 m by R. S. Allison, B. J. Gillam, and E. Vecellio (2009) for use in a 381-m-long railway tunnel. Pairs of Light Emitting Diode (LED) targets were presented either in complete darkness or with the environment lit as far as the nearest LED (the observation distance). We found that binocular, but not monocular, estimates of the depth between pairs of LEDs increased with their physical depths up to the maximum depth separation tested (248 m). Binocular estimates of depth were much larger with a lit foreground than in darkness and increased as the observation distance increased from 20 to 40 m, indicating that binocular disparity can be scaled for much larger distances than previously realized. Since these observation distances were well beyond the range of vertical disparity and oculomotor cues, this scaling must rely on perspective cues. We also ran control experiments at smaller distances, which showed that estimates of depth and distance correlate poorly and that our metric estimation method gives similar results to a comparison method under the same conditions.
Publisher: ACM
Date: 28-11-2018
Publisher: Springer International Publishing
Date: 2018
Publisher: Springer International Publishing
Date: 27-06-2019
Publisher: Springer Science and Business Media LLC
Date: 30-12-2010
DOI: 10.1007/S00221-009-2137-2
Abstract: Eye movements help capture optic-flow information necessary to perceive visually our self motion. Visual and vestibular systems control compensatory eye movements that serve to stabilize the retinal images we capture. We examined the role that these eye movements may play in generating visual illusions of self motion (or vection). Observers viewed radially expanding optic-flow displays while performing lateral translational head oscillations at 1 Hz. Simulated viewpoint changes in these displays were synchronized with head movements, either in an ipsilateral (minimal sensory conflict) or a contralateral (high sensory conflict) direction. In control conditions, the observer viewed purely radial displays. Vection-onset latency and overall vection strength ratings were recorded, as well as horizontal eye movements. Vection onsets and strength ratings were significantly greater when the observer's head movements were incorporated into the visual displays. However, vection strength ratings were very similar for both ipsilateral and contralateral active display oscillation. Surprisingly, the non-ecological contralateral viewpoint oscillation actually induced vection earlier, despite the relatively small eye-in-head rotations coordinating gaze in these conditions. Our results support the view that compensatory eye movements are controlled through cooperative visual and vestibular interactions, and show that linear vection is highly robust against large sensory conflicts.
Publisher: Elsevier BV
Date: 12-2020
Publisher: Springer Science and Business Media LLC
Date: 24-03-2021
Publisher: Springer Science and Business Media LLC
Date: 02-10-2014
DOI: 10.1007/S00221-014-4109-4
Abstract: This experiment investigated the effect of walking without optic flow on subsequent vection induction and strength. Two groups of participants walked for 5 min (either wearing Ganzfeld goggles or with normal vision) prior to exposure to a vection-inducing stimulus. We then measured the onset latency and strength of vection induced by a radially expanding pattern of optic flow. The results showed that walking without optic flow transiently yielded later vection onsets and reduced vection strength. We propose that walking without optic flow triggered a sensory readjustment, which reduced the ability of optic flow to induce self-motion perception.
Publisher: Springer Science and Business Media LLC
Date: 03-01-2020
DOI: 10.3758/S13414-019-01886-2
Abstract: Research has shown that consistent stereoscopic information improves the vection (i.e. illusions of self-motion) induced in stationary observers. This study investigates the effects of placing stereoscopic information into direct conflict with monocular motion signals by swapping the observer's left and right eye views to reverse disparity. Experiments compared the vection induced by stereo-consistent, stereo-reversed and flat-stereo patterns of: (1) same-size optic flow, which contained monocular motion perspective information about self-motion, and (2) changing-size optic flow, which provided additional monocular information about motion-in-depth based on local changes in object image sizes. As expected, consistent stereoscopic information improved the vection-in-depth induced by both changing-size and same-size patterns of optic flow. Unexpectedly, stereo-reversed patterns of same-size optic flow also induced stronger vection-in-depth than flat-stereo patterns of same-size optic flow. The effects of stereo-consistent and stereo-reversed information on vection strength were found to correlate reliably with their effects on perceived motion-in-depth and motion after-effect durations, but not with their effects on perceived scene depth. This suggests that stereo-consistent and stereo-reversed advantages for vection were both due to effects on perceived motion-in-depth. The current findings clearly demonstrate that stereoscopic information does not need to be consistent with monocular motion signals in order to improve vection. When taken together with past findings, they suggest that stereoscopic information only needs to be dynamic (as opposed to static) in order to improve vection-in-depth.
Publisher: Frontiers Media SA
Date: 27-02-2015
Publisher: ACM
Date: 12-11-2019
Publisher: Springer Science and Business Media LLC
Date: 08-03-2022
DOI: 10.1007/S10055-022-00634-6
Abstract: While head-mounted display (HMD) based gaming is often limited by cybersickness, research suggests that repeated exposure to virtual reality (VR) can reduce the severity of these symptoms. This study was therefore aimed at: (1) examining the exposure conditions required to reduce cybersickness during HMD VR and (2) learning whether such reductions generalise from one HMD VR game to another. Our participants played two commercially-available HMD VR video games over two consecutive days. Their first exposure to HMD VR on both days was always to a 15-min virtual rollercoaster ride. On Day 1, half of our participants also played a virtual climbing game for 15-min, while the rest of them finished testing early. Participants in the latter group were only exposed to the climbing game late on Day 2. We found that sickness was significantly reduced for our participants on their second exposure to the virtual rollercoaster. However, sickness to the rollercoaster on Day 2 was unaffected by whether they had played the climbing game on Day 1. Sickness during virtual climbing was also unaffected by group differences in exposure to the virtual rollercoaster. This convergent evidence suggested that the reductions in cybersickness produced by repeated exposure to HMD VR were game- specific . While these benefits did not generalise to the second game, two 15-min exposures to the same HMD VR game was sufficient to significantly reduce cybersickness in this study.
Publisher: Elsevier BV
Date: 04-2021
Publisher: Springer Science and Business Media LLC
Date: 11-05-2022
DOI: 10.1038/S41598-022-11755-Y
Abstract: Inconsistencies have been found in the relationship between ambient lighting conditions and frequency-dependence in transcranial electric stimulation (tES) induced phosphenes. Using a within-subjects design across lighting condition (dark, mesopic [dim], photopic [bright]) and tES stimulation frequency (10, 13, 16, 18, 20 Hz), this study determined phosphene detection thresholds in 24 subjects receiving tES using an FPz-Cz montage. Minima phosphene thresholds were found at 16 Hz in mesopic, 10 Hz in dark and 20 Hz in photopic lighting conditions, with these thresholds being substantially lower for mesopic than both dark (60% reduction) and photopic (56% reduction), conditions. Further, whereas the phosphene threshold-stimulation frequency relation increased with frequency in the dark and decreased with frequency in the photopic conditions, in the mesopic condition it followed the dark condition relation from 10 to 16 Hz, and photopic condition relation from 16 to 20 Hz. The results clearly demonstrate that ambient lighting is an important factor in the detection of tES-induced phosphenes, and that mesopic conditions are most suitable for obtaining overall phosphene thresholds.
Publisher: Springer Science and Business Media LLC
Date: 27-11-2018
DOI: 10.1007/S00221-017-5130-1
Abstract: Evidence is mounting that differences in postural instability can be used to predict who will experience strong illusory self-motions (vection) and become sick when exposed to global patterns of optical flow (e.g., Apthorp et al., PLoS One 9(12):e113897, 2014 Stoffregen and Smart, Brain Res Bull 47:437-448, 1998). This study compared the predictive ability of traditional and recurrence quantification analysis (RQA) based measures of postural activity. We initially measured spontaneous fluctuations in the centre of foot pressure (CoP) of our subjects as they stood quietly with their eyes open and closed. They were then repeatedly exposed to two different types of self-motion display. As expected, the oscillating self-motion displays were found to induce stronger vection and greater sickness than the smooth self-motion displays. RQA based measures of spontaneous postural activity proved to be superior predictors of both vection strength and visually induced motion sickness (VIMS). Participants who had displayed lower CoP recurrence rates when standing quietly were more likely to later report stronger vection and VIMS when exposed to both types of optical flow. Vection strength (but not VIMS) was also found to correlate significantly with three other RQA based measures of postural activity (determinism, entropy, and average diagonal line length). We propose that these RQA based measures of spontaneous postural activity could serve as useful diagnostic tools for evaluating who will benefit the most/least from exposure to virtual environments.
Publisher: Informa UK Limited
Date: 03-2006
Publisher: ACM
Date: 08-12-2021
Publisher: SAGE Publications
Date: 2012
DOI: 10.1068/P7206
Abstract: 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”.
Publisher: SAGE Publications
Date: 2008
DOI: 10.1068/P5781
Abstract: 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 were measured for 30 s with a computer-interfaced slide device. Vection onset was significantly faster, and vection magnitude stronger, when a contracting pattern was viewed. We propose that our extensive experience with forward self-motion may form a neural expectancy (exposure-history) about the sensory inputs which typically accompany expanding flow. However, since backward self-motion is less common, there may be a weaker exposure-history for contracting flow, and as a result these patterns generate less salient sensory conflict and subsequently less vection.
Publisher: Wiley
Date: 23-07-2019
DOI: 10.1002/BEM.22209
Abstract: It is well known that applying transcranial alternating current stimulation (tACS) to the scalp can generate artefactual visual perceptions of flashing or shimmering light known as phosphenes. The thresholds for generating these phosphenes have been used by international standards bodies to provide conservative estimates of the field strength required to interfere with human neural functioning and set safety limits accordingly. However, the precise relationship between electric currents and phosphene perception thresholds remains uncertain. The present study used tACS to systematically investigate the effects of the location and the frequency of stimulation on phosphene perception thresholds. These thresholds were obtained from 24 participants using a within-subject design as a function of scalp stimulation sites (FPz-Cz versus Oz-Cz) and stimulation frequency (2-30 Hz in steps of 2 Hz). Phosphene perception thresholds were consistently lower for FPz-Cz stimulation, and regardless of tACS location were lowest for 16 Hz stimulation. Threshold variation between participants was very small, which is meaningful when setting standards based on phosphenes. Bioelectromagnetics. 2019 :365-374. © 2019 Bioelectromagnetics Society.
Publisher: Elsevier BV
Date: 07-2014
DOI: 10.1016/J.VISRES.2014.04.012
Abstract: Gradients of absolute binocular disparity across a slanted surface are often considered the basis for stereoscopic slant perception. However, perceived stereo slant around a vertical axis is usually slow and significantly under-estimated for isolated surfaces. Perceived slant is enhanced when surrounding surfaces provide a relative disparity gradient or depth step at the edges of the slanted surface, and also in the presence of monocular occlusion regions (sidebands). Here we investigate how different kinds of depth information at surface edges enhance stereo slant about a vertical axis. In Experiment 1, perceived slant decreased with increasing surface width, suggesting that the relative disparity between the left and right edges was used to judge slant. Adding monocular sidebands increased perceived slant for all surface widths. In Experiment 2, observers matched the slant of surfaces that were isolated or had a context of either monocular or binocular sidebands in the frontal plane. Both types of sidebands significantly increased perceived slant, but the effect was greater with binocular sidebands. These results were replicated in a second paradigm in which observers matched the depth of two probe dots positioned in front of slanted surfaces (Experiment 3). A large bias occurred for the surface without sidebands, yet this bias was reduced when monocular sidebands were present, and was nearly eliminated with binocular sidebands. Our results provide evidence for the importance of edges in stereo slant perception, and show that depth from monocular occlusion geometry and binocular disparity may interact to resolve complex 3D scenes.
Publisher: Elsevier BV
Date: 12-2011
DOI: 10.1016/J.VISRES.2011.10.007
Abstract: We added simulated vertical viewpoint jitter and oscillation to radial optic flow displays designed to induce forward vection. Display jitter and oscillation were both found to increase vection strength during, and reduce motion aftereffects (MAE) following, exposure to the optic flow (compared to no-jitter controls). Display jitter, which induced the strongest vection of all the conditions tested, was also found to increase the duration of vection aftereffects (VAE).
Publisher: Association for Research in Vision and Ophthalmology (ARVO)
Date: 10-11-2016
DOI: 10.1167/16.14.7
Abstract: Although observer motions project different patterns of optic flow to our left and right eyes, there has been surprisingly little research into potential stereoscopic contributions to self-motion perception. This study investigated whether visually induced illusory self-motion (i.e., vection) is influenced by the addition of consistent stereoscopic information to radial, circular, and spiral (i.e., combined radial + circular) patterns of optic flow. Stereoscopic vection advantages were found for radial and spiral (but not circular) flows when monocular motion signals were strong. Under these conditions, stereoscopic benefits were greater for spiral flow than for radial flow. These effects can be explained by differences in the motion aftereffects generated by these displays, which suggest that the circular motion component in spiral flow selectively reduced adaptation to stereoscopic motion-in-depth. Stereoscopic vection advantages were not observed for circular flow when monocular motion signals were strong, but emerged when monocular motion signals were weakened. These findings show that stereoscopic information can contribute to visual self-motion perception in multiple ways.
Publisher: SAGE Publications
Date: 2012
DOI: 10.1068/P6919
Abstract: 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 of simulated head oscillation significantly reduced vection onset latencies relative to pure radial flow. Simultaneous eye-movement recordings showed that slow-phase ocular following responses (OFRs) were induced in both linear and angular viewpoint oscillation conditions. Vection strength was significantly reduced by active central fixation when viewing displays which simulated angular, but not linear, head oscillation. When these displays with angular oscillation were viewed without stable fixation, vection strength was found to increase with the velocity and regularity of the OFR. We conclude that vection improvements observed during central viewing of displays with angular viewpoint oscillation depend on the generation of eye movements.
Publisher: Elsevier BV
Date: 08-2020
Publisher: American Psychological Association (APA)
Date: 2005
Publisher: SAGE Publications
Date: 2011
DOI: 10.1068/P6915
Abstract: The hollow-face illusion involves a misperception of depth order: our perception follows our top–down knowledge that faces are convex, even though bottom–up depth information reflects the actual concave surface structure. While pictorial cues can be ambiguous, stereopsis should unambiguously indicate the actual depth order. We used computer-generated stereo images to investigate how, if at all, the sign and magnitude of binocular disparities affect the perceived depth of the illusory convex face. In experiment 1 participants adjusted the disparity of a convex comparison face until it matched a reference face. The reference face was either convex or hollow and had binocular disparities consistent with an average face or had disparities exaggerated, consistent with a face stretched in depth. We observed that apparent depth increased with disparity magnitude, even when the hollow faces were seen as convex (ie when perceived depth order was inconsistent with disparity sign). As expected, concave faces appeared flatter than convex faces, suggesting that disparity sign also affects perceived depth. In experiment 2, participants were presented with pairs of real and illusory convex faces. In each case, their task was to judge which of the two stimuli appeared to have the greater depth. Hollow faces with exaggerated disparities were again perceived as deeper.
Publisher: SAGE Publications
Date: 2011
DOI: 10.1068/P6878
Abstract: We directly compared recognition for faces following 0° – 75° viewpoint rotation about the yaw, pitch, and roll axes. The aim was to determine the extent to which configural and featural information supported face recognition following rotations about each of these axes. Experiment 1 showed that performance on a sequential-matching task was viewpoint-dependent for all three types of rotation. The best face-recognition accuracy and shortest reaction time was found for roll rotations, then for yaw rotations, and finally the worst accuracy and slowest reaction time was found for pitch rotations. Directional differences in recognition were found for pitch rotations, but not for roll or yaw. Experiment 2 provided evidence that, in all three cases, viewpoint-dependent declines in recognition were primarily driven by the loss of configural information. However, it also appeared that significant featural information was lost following yaw and pitch (but not roll) rotations. Together, these findings show that unfamiliar-face recognition is viewpoint-dependent following rotation about each axis (and in each direction), and that performance is based on the availability of configural and, to a lesser extent, featural information.
Publisher: Frontiers Media SA
Date: 13-04-2022
DOI: 10.3389/FRVIR.2022.860919
Abstract: Visually induced illusions of self-motion (vection) are thought to cause cybersickness during head-mounted display based virtual reality (HMD VR). However, the empirical support for this widespread belief is rather mixed. Our exploratory study examined the possibility that only unexpected experiences of vection provoke cybersickness. Fifteen males and 15 females played an HMD VR game (Mission: ISS) for up to 14 min with: 1) their experiences of vection and cybersickness assessed every 2 minutes and 2) the game being terminated whenever they reported feeling sick. Of the 30 participants tested, 17 reported feeling sick and 13 remained well. Sick and well participants did not differ in terms of the strength of their vection experiences. However, the sick participants were significantly more likely to report unexpected/uncontrolled vection. When these data were subjected to machine learning analysis, unexpected vection was found to be the most important predictor of cybersickness. These preliminary findings suggest that vection can be used to safely enhance experiences in HMD VR–as long as developers ensure that any simulated self-motions are expected and perceived to be under the user’s control.
Publisher: Association for Research in Vision and Ophthalmology (ARVO)
Date: 03-02-2021
DOI: 10.1167/IOVS.62.2.4
Publisher: Aerospace Medical Association
Date: 10-2007
Abstract: The current study investigated the effects that vertical display oscillation had on the development of both vection and simulator sickness. There were 16 subjects who were exposed to optic flow displays which simulated either: 1) constant velocity forward self-motion (pure radial flow) or 2) 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 eight symptoms listed on the Subjective Symptoms of Motion Sickness (SSMS) scale at 2-min intervals. Subjects also completed the Simulator Sickness Questionnaire (SSQ) designed by Kennedy and colleagues before and after each trial, which generated a total SSQ score and three SSQ subscores (nausea, oculomotor symptoms, and disorientation). Vertically oscillating displays (mean = 5.51 SD = 2.5) were found to produce significantly stronger vection ratings than non-oscillating displays (mean = 3.56 SD = 2.1). Vertically oscillating displays (mean = 58.18 SD = 32.2) were also found to produce significantly more severe sickness (as rated by total SSQ scores) than non-oscillating displays (mean = 29.67 SD = 24.7). Both vection and sickness symptoms increased in magnitude with prolonged exposure to optic flow. Our findings appear to represent a special case in visual self-motion perception where high-frequency vertical oscillation both enhances vection and increases simulator sickness when it is incorporated into an optic flow display simulating constant velocity self-motion in depth.
Publisher: Elsevier BV
Date: 07-2019
Publisher: ACM
Date: 17-11-2019
Publisher: SAGE Publications
Date: 2015
DOI: 10.1068/P7717
Abstract: Investigations of change detection consistently reveal an effect of change magnitude: changes involving more object parts are detected more easily than those involving fewer parts. Whether large changes improve detection by providing stronger preattentive signals to the change location is subject to debate. We report a cued object change detection experiment that tested this hypothesis while controlling for stimulus familiarity, semantic knowledge, and change type (addition versus deletion). We found strong magnitude effects regardless of whether trials were validly or invalidly cued. The size of the cueing effects, which were exhibited for all the change magnitudes examined, did not decrease with the number of parts changing. These findings provide little support for a preattentive guidance hypothesis and instead support the thesis that change detection requires attention.
Publisher: Wiley
Date: 13-01-2021
DOI: 10.1002/BEM.22317
Publisher: Springer Science and Business Media LLC
Date: 11-2006
DOI: 10.3758/BF03193725
Abstract: Although traditionally there has been a debate over whether object recognition involves 3-D structural descriptions or 2-D views, most current approaches to object recognition include the representation of object structure in some form. An advantage for the processing of structural or configural information in objects has been recently demonstrated using a change detection task (Keane, Hayward, and Burke, 2003). We report two experiments that extend this finding and show that configural information dominates change detection performance regardless of an object's orientation. Experiment 1 demonstrated the advantage that configural information has over shape and part arrangement information in change detection across four different object rotations in depth. Experiment 2 showed that this advantage occurs for both categorical and coordinate configural changes. These results are consistent with the hypothesis that configural information is a critical feature of object representations and that this information is utilized effectively in object recognition across changes in viewpoint.
Publisher: Springer Science and Business Media LLC
Date: 02-02-2016
DOI: 10.1007/S00221-016-4564-1
Abstract: When a single light cue is given in the visual field, our eyes orient towards it with an average latency of 200 ms. If a second cue is presented at or around the time of the response to the first, a secondary eye movement occurs that represents a reorientation to the new target. While studies have shown that eye movement latencies to 'single-step' targets may or may not be lengthened with age, secondary eye movements (during 'double-step' displacements) are significantly delayed with increasing age. The aim of this study was to investigate whether the postural challenge posed simply by standing (as opposed to sitting) results in significantly longer eye movement latencies in older adults compared to the young. Ten young ( 65 years) participated in the study. They were required to fixate upon a central target and move their eyes in response to 2 types of stimuli: (1) a single-step perturbation of target position either 15° to the right or left and (2) a double-step target displacement incorporating an initial target jump to the right or left by 15°, followed after 200 ms, by a shift of target position to the opposite side (e.g. +15° then -15°). All target displacement conditions were executed in sit and stand positions with the participant at the same distance from the targets. Eye movements were recorded using electro-oculography. Older adults did not show significantly longer eye movement latencies than the younger adults for single-step target displacements, and postural configuration (stand compared to sit) had no effect upon latencies for either group. We categorised double-step trials into those during which the second light changed after or before the onset of the eye shift to the first light. For the former category, young participants showed faster secondary eye shifts to the second light in the standing position, while the older adults did not. For the latter category of double-step trial, young participants showed no significant difference between sit and stand secondary eye movement latencies, but older adults were significantly longer standing compared to sitting. The older adults were significantly longer than the younger adults across both postural conditions, regardless of when the second light change occurred during the eye shift to the first light. We suggest that older adults require greater time and perhaps attentional processes to execute eye movements to unexpected changes in target position when faced with the need to maintain standing balance.
Publisher: Aerospace Medical Association
Date: 09-2013
Abstract: When we ride on a roller coaster, our experience of self-motion is accompanied by salient changes in gravitoinertial force. Here we examined whether a similar relationship exists between visually induced self-motion (vection) and perceived gravitoinertial force. There were 15 stationary subjects, each wearing a weight jacket, who were exposed to visual displays simulating upward, backward, or no self-motion. At the end of each 30-s display exposure, subjects: 1) rated the strength of their vection experience and 2) had the experimenter add/remove weights from their weight jackets to recreate their perceived weight during exposure to the stimulus display. We found that upward vection increased and downward vection decreased perceived weight. Importantly, the size of these perceived weight changes depended on the strength of the vection experience. We conclude that the observed strong relationship between vection and perceived weight stems from the brain's attempt to reconcile the inputs from the different self-motion senses. The current findings have important implications for all simulated self-motions either in virtual reality or in vehicle simulators (particularly fixed-base flight and driving simulators).
Publisher: Frontiers Media SA
Date: 12-11-2020
Publisher: Frontiers Media SA
Date: 13-03-2015
Publisher: Springer Science and Business Media LLC
Date: 23-10-2019
DOI: 10.3758/S13414-018-1609-5
Abstract: Research has previously shown that adding consistent stereoscopic information to self-motion displays can improve the vection in depth induced in physically stationary observers. In some past studies, the simulated eye-separation was always close to the observer's actual eye-separation, as the aim was to examine vection under ecological viewing conditions that provided consistent binocular and monocular self-motion information. The present study investigated whether large discrepancies between the observer's simulated and physical eye-separations would alter the vection-inducing potential of stereoscopic optic flow (either helping, hindering, or preventing the induction of vection). Our self-motion displays simulated eye-separations of 0 cm (the non-stereoscopic control), 3.25 cm (reduced from normal), 6.5 cm (approximately normal), and 13 cm (exaggerated relative to normal). The rated strength of vection in depth was found to increase systematically with the simulated eye-separation. While vection was the strongest in the 13-cm condition (stronger than even the 6.5-cm condition), the 3.25-cm condition still produced superior vection to the 0-cm control (i.e., it had significantly stronger vection ratings and shorter onset latencies). Perceptions of scene depth and object motion-in-depth speed were also found to increase with the simulated eye-separation. As expected based on the findings of previous studies, correlational analyses suggested that the stereoscopic advantage for vection (found for all of our non-zero eye-separation conditions) was due to the increase in perceived motion-in-depth.
Publisher: SAGE Publications
Date: 24-11-2017
Publisher: SAGE Publications
Date: 2011
DOI: 10.1068/P6868
Abstract: Static and dynamic observers provided binocular and monocular estimates of the depths between real objects lying well beyond interaction space. On each trial, pairs of LEDs were presented inside a dark railway tunnel. The nearest LED was always 40 m from the observer, with the depth separation between LED pairs ranging from 0 up to 248 m. Dynamic binocular viewing was found to produce the greatest (ie most veridical) estimates of depth magnitude, followed next by static binocular viewing, and then by dynamic monocular viewing. (No significant depth was seen with static monocular viewing.) We found evidence that both binocular and monocular dynamic estimates of depth were scaled for the observation distance when the ground plane and walls of the tunnel were visible up to the nearest LED. We conclude that both motion parallax and stereopsis provide useful long-distance depth information and that motion-parallax information can enhance the degree of stereoscopic depth seen.
Publisher: Frontiers Media SA
Date: 10-08-2016
Publisher: Frontiers Media SA
Date: 2012
Start Date: 2021
End Date: 2024
Funder: Australian Research Council
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End Date: 2024
Funder: Australian Research Council
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End Date: 2010
Funder: Australian Research Council
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End Date: 2009
Funder: Australian Research Council
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End Date: 2013
Funder: Australian Research Council
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Funder: Australian Research Council
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End Date: 12-2024
Amount: $199,000.00
Funder: Australian Research Council
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Funder: Australian Research Council
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Funder: Australian Research Council
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End Date: 12-2009
Amount: $135,000.00
Funder: Australian Research Council
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End Date: 05-2026
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Funder: Australian Research Council
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Funder: Australian Research Council
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End Date: 06-2024
Amount: $548,940.00
Funder: Australian Research Council
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