Perceived Rigidity Significantly Affects Visually Induced Self-Motion Perception (Vection)

Perception ◽  
2019 ◽  
Vol 48 (5) ◽  
pp. 386-401 ◽  
Author(s):  
Shinji Nakamura
Keyword(s):  
Motion Perception ◽  
Visual Stimulus ◽  
Wave Amplitude ◽  
Sine Wave ◽  
Psychophysical Experiment ◽  
Stimulus Motion ◽  
Lower Amplitude ◽  
Self Motion ◽  
Perceived Speed

When an observer sees a uniformly moving visual stimulus, he or she typically perceives an illusory motion of his or her body in the opposite direction (vection). In this study, the effects of the visual inducer’s perceived rigidity were examined using a horizontal sine wave-like line stimulus moving horizontally. Lowering the sine wave amplitude resulted in the perception of a less rigid visual stimulus motion, although the stimulus was always set to move completely rigidly. The psychophysical experiment revealed that visual self-motion perception was weaker in the lower amplitude condition where the visual stimulus was perceived as less rigid. The follow-up experiments showed that the effects of sine wave amplitude manipulation were unrelated to the modulation of the perceived speed. Furthermore, small gaps inserted into the sine waves effectively increased the perceived rigidity and resulted in a strong self-motion perception even in the lower amplitude condition. The current investigation, together with previous studies, clearly demonstrated that perceived features, in addition to the physical ones, play a key role in visual self-motion perception. Visual stimuli, perceived as more rigid, provide a more reliable frame of reference in the observers’ spatial orientation, determining their self-motion perception.

Separate Presentation of Additional Accelerating Motion Does not Enhance Visually Induced Self-Motion Perception

2013 ◽  
Vol 26 (3) ◽  
pp. 277-285 ◽  
Author(s):  
Shinji Nakamura
Keyword(s):  
Motion Perception ◽  
Visual Motion ◽  
Main Axis ◽  
Psychophysical Experiment ◽  
Simple Hypothesis ◽  
Expansion Pattern ◽  
Perception Of Self ◽  
Oscillating Motion ◽  
Self Motion ◽  
Perceptual Mechanism

It has been repeatedly reported that visual stimuli containing a jittering/oscillating motion component can induce self-motion perception more strongly than a pure radial expansion pattern. A psychophysical experiment with 11 observers revealed that the additional accelerating components of the visual motion have to be convoluted with the motion of the main-axis to facilitate self-motion perception; additional motion presented in an isolated fashion impairs the perception of self-motion. These results are inconsistent with a simple hypothesis about the perceptual mechanism underlying the advantage of jitter/oscillation, which assumes that the accelerating component induces an additional self-motion independently of the main motion at the first stage, and then the two self-motions induced by the main motion and the additional component become integrated.

Color effects on self-motion perception

2006 ◽  
Author(s):  
Frederick Bonato ◽  
Andrea Bubka
Keyword(s):  
Motion Perception ◽  
Self Motion

Disruption of self-motion perception without vestibular reflex alteration in ménière’s disease

2021 ◽  
pp. 1-11
Author(s):  
Mario Faralli ◽  
Michele Ori ◽  
Giampietro Ricci ◽  
Mauro Roscini ◽  
Roberto Panichi ◽  
...  
Keyword(s):  
Motion Perception ◽  
Meniere’S Disease ◽  
Menière’S Disease ◽  
Whole Body ◽  
Meniere's Disease ◽  
Ménière’S Disease ◽  
Menière's Disease ◽  
Ocular Reflex ◽  
Ménière's Disease ◽  
Self Motion

BACKGROUND: Self-motion misperception has been observed in vestibular patients during asymmetric body oscillations. This misperception is correlated with the patient’s vestibular discomfort. OBJECTIVE: To investigate whether or not self-motion misperception persists in post-ictal patients with Ménière’s disease (MD). METHODS: Twenty-eight MD patients were investigated while in the post-ictal interval. Self-motion perception was studied by examining the displacement of a memorized visual target after sequences of opposite directed fast-slow asymmetric whole body rotations in the dark. The difference in target representation was analyzed and correlated with the Dizziness Handicap Inventory (DHI) score. The vestibulo-ocular reflex (VOR) and clinical tests for ocular reflex were also evaluated. RESULTS: All MD patients showed a noticeable difference in target representation after asymmetric rotation depending on the direction of the fast/slow rotations. This side difference suggests disruption of motion perception. The DHI score was correlated with the amount of motion misperception. In contrast, VOR and clinical trials were altered in only half of these patients. CONCLUSIONS: Asymmetric rotation reveals disruption of self-motion perception in MD patients during the post-ictal interval, even in the absence of ocular reflex impairment. Motion misperception may cause persistent vestibular discomfort in these patients.

Cognitive factors can influence self-motion perception (vection) in virtual reality

2006 ◽  
Vol 3 (3) ◽  
pp. 194-216 ◽  
Author(s):  
Bernhard E. Riecke ◽  
Jörg Schulte-Pelkum ◽  
Marios N. Avraamides ◽  
Markus Von Der Heyde ◽  
Heinrich H. Bülthoff
Keyword(s):  
Virtual Reality ◽  
Motion Perception ◽  
Cognitive Factors ◽  
Self Motion

Electrical characteristics of pacing different portions of the His bundle in bradycardia patients

EP Europace ◽  
2020 ◽  
Vol 22 (Supplement_2) ◽  
pp. ii27-ii35
Author(s):  
Yiran Hu ◽  
Min Gu ◽  
Wei Hua ◽  
Hongxia Niu ◽  
Hui Li ◽  
...  
Keyword(s):  
Wave Amplitude ◽  
Electrical Characteristics ◽  
Normal Range ◽  
Tricuspid Valve Regurgitation ◽  
His Bundle ◽  
His Bundle Pacing ◽  
Pacing Mode ◽  
Echocardiographic Assessment ◽  
R Wave Amplitude

Abstract Aims His-bundle pacing (HBP) can be achieved in either atrial-side HBP (aHBP) or ventricular-side HBP (vHBP). The study compared the pacing parameters and electrophysiological characteristics between aHBP and vHBP in bradycardia patients. Methods and results Fifty patients undergoing HBP implantation assisted by visualization of the tricuspid valvular annulus (TVA) were enrolled. The HBP lead position was identified by TVA angiography. Twenty-five patients were assigned to undergo aHBP and compared with 25 patients who underwent vHBP primarily in a prospective and randomized fashion. Pacing parameters and echocardiography were routinely assessed at implant and 3-month follow-up. His-bundle pacing was successfully performed in 45 patients (90% success rate with 44.4% aHBP and 55.6% vHBP). The capture threshold was lower in vHBP than aHBP at implant (vHBP: 1.1 ± 0.5 vs. aHBP: 1.4 ± 0.4 V/1.0 ms, P = 0.014) and 3-month follow-up (vHBP: 0.8 ± 0.4 vs. aHBP: 1.7 ± 0.8 V/0.4 ms, P < 0.001). The R-wave amplitude was higher in vHBP than in aHBP at implant (vHBP: 4.5 ± 1.4 vs. aHBP: 2.0 ± 0.8 mV, P < 0.001) and at 3-month follow-up (vHBP: 4.4 ± 1.5 vs. aHBP: 1.8 ± 0.7 mV, P < 0.001). No procedure-related complications and aggravation of tricuspid valve regurgitation were observed in most patients and echocardiographic assessment of cardiac function remained in the normal range in all patients during the follow-up. Conclusion This study demonstrates that vHBP features a low and stable pacing capture threshold and high R-wave amplitude, suggesting better pacing mode management and battery longevity can be achieved by HBP in the ventricular side.

Self-motion perception: Assessment by computer-generated animations

1998 ◽  
Vol 42 (1-8) ◽  
pp. 273-280 ◽  
Author(s):  
D.E Parker ◽  
D.L Harm ◽  
G.R Sandoz ◽  
N.C Skinner
Keyword(s):  
Motion Perception ◽  
Self Motion

Perceived self-motion in two visual contexts: Dissociable mechanisms underlie perception

2006 ◽  
Vol 16 (1-2) ◽  
pp. 23-28 ◽  
Author(s):  
W. Geoffrey Wright ◽  
Paul DiZio ◽  
James R. Lackner
Keyword(s):  
Motion Perception ◽  
Path Integration ◽  
Visual Input ◽  
Visual Scene ◽  
Spatial Context ◽  
Immersive Virtual Environment ◽  
Physical Context ◽  
The Subject ◽  
Self Motion ◽  
Visual Acceleration

We evaluated the influence of moving visual scenes and knowledge of spatial and physical context on visually induced self-motion perception in an immersive virtual environment. A sinusoidal, vertically oscillating visual stimulus induced perceptions of self-motion that matched changes in visual acceleration. Subjects reported peaks of perceived self-motion in synchrony with peaks of visual acceleration and opposite in direction to visual scene motion. Spatial context was manipulated by testing subjects in the environment that matched the room in the visual scene or by testing them in a separate chamber. Physical context was manipulated by testing the subject while seated in a stable, earth-fixed desk chair or in an apparatus capable of large linear motions, however, in both conditions no actual motion occurred. The compellingness of perceived self-motion was increased significantly when the spatial context matched the visual input and actual body displacement was possible, however, the latency and amplitude of perceived self-motion were unaffected by the spatial or physical context. We propose that two dissociable processes are involved in self-motion perception: one process, primarily driven by visual input, affects vection latency and path integration, the other process, receiving cognitive input, drives the compellingness of perceived self-motion.

Abstract 062: Aortic Stiffness, Blood Pressure Progression and Incident Hypertension: The Framingham Heart Study

Circulation ◽  
2012 ◽  
Vol 125 (suppl_10) ◽  
Author(s):  
Bernhard M Kaess ◽  
Jian Rong ◽  
Martin G Larson ◽  
Naomi M Hamburg ◽  
Joseph A Vita ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Brachial Artery ◽  
Aortic Stiffness ◽  
Wave Amplitude ◽  
Augmentation Index ◽  
Vascular Stiffness ◽  
Flow Mediated Dilation ◽  
Forward Wave ◽  
Incident Hypertension

Background: Increased vascular stiffness and excessive blood pressure (BP) pulsatility are important risk factors for age-related morbidity. Vascular stiffness and BP pulsatility are related, with a prevailing view that hypertension antedates and contributes to premature vascular aging and a secondary increase in vascular stiffness. However, temporal relations between comprehensive vascular measures and BP elevation have not been fully delineated in a large community-based sample. Methods: We examined longitudinal relations of BP and 3 measures of vascular stiffness and pressure pulsatility derived from arterial tonometry (carotid-femoral pulse wave velocity [CFPWV], forward wave amplitude and augmentation index) over a 7-year period in 1,898 Framingham Offspring participants (mean age 60 yrs, 1,057 women). We also examined relations between measures of microvascular and endothelial function derived from brachial artery Doppler and future progression of BP or vascular stiffness. Results: In multivariable-adjusted regression models, baseline tonometry measures were separately and jointly associated with higher systolic and pulse pressure and incident hypertension ( Table ). Conversely, higher baseline BP was associated with higher forward wave amplitude and augmentation index (all p<0.05) but not CFPWV at follow-up. Higher baseline resting brachial artery flow and lower flow-mediated dilation were associated with incident hypertension in models that included BP and tonometry measures ( Table ). Conclusion: Higher aortic stiffness (CFPWV), pressure pulsatility (forward wave amplitude), and wave reflection (augmentation index) and lower flow-mediated dilation are associated with blood pressure progression and incident hypertension. Our findings support the notion of aortic stiffness as a precursor of hypertension and further suggest a vicious cycle of increasing pressure pulsatility with advancing age. Table. Correlates of incident hypertension. Predictor Variables (baseline) OR 95% CI P Systolic BP 3.24 (2.17; 4.84) <0.0001 Diastolic BP 1.47 (1.13; 1.92) 0.0042 CFPWV 1.30 (1.02; 1.67) 0.037 Forward wave amplitude 1.66 (1.32; 2.09) <0.0001 Augmentation index 1.78 (1.45; 2.17) <0.0001 Brachial artery baseline flow 1.23 (1.05; 1.45) 0.013 Flow-mediated dilation 0.83 (0.70; 0.98) 0.029 Results of a single multivariable model that further adjusted for age,sex, BMI, height and triglycerides in 1,019 participants free of hypertension at baseline who experienced 337 cases of incident hypertension during follow-up. OR expressed per 1 SD of the independent variable.

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