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Journal articles on the topic 'Perception of Occlusion'

Author: Grafiati

Published: 4 June 2021

Last updated: 1 February 2022

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1

Nakashima, Ryoichi, and Takatsune Kumada. "Peripersonal versus extrapersonal visual scene information for egocentric direction and position perception." Quarterly Journal of Experimental Psychology 71, no. 5 (January 1, 2018): 1090–99. http://dx.doi.org/10.1080/17470218.2017.1310267.

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When perceiving the visual environment, people simultaneously perceive their own direction and position in the environment (i.e., egocentric spatial perception). This study investigated what visual information in a scene is necessary for egocentric spatial perceptions. In two perception tasks (the egocentric direction and position perception tasks), observers viewed two static road images presented sequentially. In Experiment 1, the critical manipulation involved an occluded region in the road image, an extrapersonal region (far-occlusion) and a peripersonal region (near-occlusion). Egocentric direction perception was worse in the far-occlusion condition than in the no-occlusion condition, and egocentric position perceptions were worse in the far- and near-occlusion conditions than in the no-occlusion condition. In Experiment 2, we conducted the same tasks manipulating the observers’ gaze location in a scene—an extrapersonal region (far-gaze), a peripersonal region (near-gaze) and the intermediate region between the former two (middle-gaze). Egocentric direction perception performance was the best in the far-gaze condition, and egocentric position perception performances were not different among gaze location conditions. These results suggest that egocentric direction perception is based on fine visual information about the extrapersonal region in a road landscape, and egocentric position perception is based on information about the entire visual scene.

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2

Xu, Jie, Hanyuan Wang, Mingzhu Xu, Fan Yang, Yifei Zhou, and Xiaolong Yang. "Feature-Enhanced Occlusion Perception Object Detection for Smart Cities." Wireless Communications and Mobile Computing 2021 (March 29, 2021): 1–14. http://dx.doi.org/10.1155/2021/5544194.

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Object detection is used widely in smart cities including safety monitoring, traffic control, and car driving. However, in the smart city scenario, many objects will have occlusion problems. Moreover, most popular object detectors are often sensitive to various real-world occlusions. This paper proposes a feature-enhanced occlusion perception object detector by simultaneously detecting occluded objects and fully utilizing spatial information. To generate hard examples with occlusions, a mask generator localizes and masks discriminated regions with weakly supervised methods. To obtain enriched feature representation, we design a multiscale representation fusion module to combine hierarchical feature maps. Moreover, this method exploits contextual information by heaping up representations from different regions in feature maps. The model is trained end-to-end learning by minimizing the multitask loss. Our model obtains superior performance compared to previous object detectors, 77.4% mAP and 74.3% mAP on PASCAL VOC 2007 and PASCAL VOC 2012, respectively. It also achieves 24.6% mAP on MS COCO. Experiments demonstrate that the proposed method is useful to improve the effectiveness of object detection, making it highly suitable for smart cities application that need to discover key objects with occlusions.

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3

Lee, Abigail, Robert Allison, and Laurie Wilcox. "Depth perception from successive occlusion." Journal of Vision 21, no. 9 (September 27, 2021): 1963. http://dx.doi.org/10.1167/jov.21.9.1963.

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4

Palmer, E. M., and P. J. Kellman. "(Mis)Perception of motion and form after occlusion: Anorthoscopic perception revisited." Journal of Vision 3, no. 9 (March 16, 2010): 251. http://dx.doi.org/10.1167/3.9.251.

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5

Ramachandran, V. S., V. Inada, and G. Kiama. "Perception of illusory occlusion in apparent motion." Vision Research 26, no. 10 (January 1986): 1741–49. http://dx.doi.org/10.1016/0042-6989(86)90061-1.

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6

Vallortigara, Giorgio, and Paola Bressan. "Occlusion and the perception of coherent motion." Vision Research 31, no. 11 (January 1991): 1967–78. http://dx.doi.org/10.1016/0042-6989(91)90191-7.

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7

Häkkinen, Jukka, and Göte Nyman. "Occlusion Constraints and Stereoscopic Slant." Perception 26, no. 1 (January 1997): 29–38. http://dx.doi.org/10.1068/p260029.

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In binocular vision horizontal magnification of one retinal image leads to a percept of three-dimensional slant around a vertical axis. It is demonstrated that the perception of slant is diminished when an occlusion interpretation is possible. A frontoparallel plane located in the immediate vicinity of a slanted surface in a location which allows a perception of occlusion reduces the magnitude of perceived slant significantly. When the same plane is placed on the other side, the slant perception is normal because there is no alternative occlusion interpretation. The results indicate that a common border between the occluder and a slanted surface is not a necessary condition for the reduction effect. If the edges are displaced and the edge of the slanted surface is placed in a location in which it could be occluded, the effect still appears.

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8

Ono, Hiroshi, Brian J. Rogers, Masao Ohmi, and Mika E. Ono. "Dynamic Occlusion and Motion Parallax in Depth Perception." Perception 17, no. 2 (April 1988): 255–66. http://dx.doi.org/10.1068/p170255.

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Random-dot techniques were used to examine the interactions between the depth cues of dynamic occlusion and motion parallax in the perception of three-dimensional (3-D) structures, in two different situations: (a) when an observer moved laterally with respect to a rigid 3-D structure, and (b) when surfaces at different distances moved with respect to a stationary observer. In condition (a), the extent of accretion/deletion (dynamic occlusion) and the amount of relative motion (motion parallax) were both linked to the motion of the observer. When the two cues specified opposite, and therefore contradictory, depth orders, the perceived order in depth of the simulated surfaces was dependent on the magnitude of the depth separation. For small depth separations, motion parallax determined the perceived order, whereas for large separations it was determined by dynamic occlusion. In condition (b), where the motion parallax cues for depth order were inherently ambiguous, depth order was determined principally by the unambiguous occlusion information.

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9

Andersen, George J., and James M. Cortese. "2-D contour perception resulting from kinetic occlusion." Perception & Psychophysics 46, no. 1 (January 1989): 49–55. http://dx.doi.org/10.3758/bf03208073.

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10

Gillam, B. "Shape and meaning in the perception of occlusion." Journal of Vision 7, no. 9 (March 23, 2010): 608. http://dx.doi.org/10.1167/7.9.608.

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11

Gordon, Michael S., and Lawrence D. Rosenblum. "Perception of acoustic occlusion using body‐scaled judgments." Journal of the Acoustical Society of America 107, no. 5 (May 2000): 2851. http://dx.doi.org/10.1121/1.429222.

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12

Jutras, Benoît, Antonia Lüönd, Flurin Honegger, Christof Stieger, Thomas Hummel, and Antje Welge-Lüssen. "Influence of external ear occlusion on food perception." European Archives of Oto-Rhino-Laryngology 276, no. 3 (February 18, 2019): 889–95. http://dx.doi.org/10.1007/s00405-019-05296-w.

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13

Boselie, Frans. "Local and Global Factors in Visual Occlusion." Perception 23, no. 5 (May 1994): 517–28. http://dx.doi.org/10.1068/p230517.

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Although interest in the phenomenon of visual occlusion is of very long standing, only a small number of experimental studies have been reported, and available theories fail to give satisfactory explanations of the data. In this paper the efficacy of local factors in organising the perception of globally regular occlusion patterns is explored. Three experiments are reported in which the relative contribution of local and global factors to the salience of percepts is investigated. It is demonstrated that local factors play a very important role in the perception of these kinds of patterns.

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14

Zhou, Shuren, Jie Wu, Fan Zhang, and Paramjit Sehdev. "Depth occlusion perception feature analysis for person re-identification." Pattern Recognition Letters 138 (October 2020): 617–23. http://dx.doi.org/10.1016/j.patrec.2020.09.009.

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15

Brenton, John, Sean Müller, Robbie Rhodes, and Brad Finch. "Automated vision occlusion-timing instrument for perception–action research." Behavior Research Methods 50, no. 1 (February 23, 2017): 228–35. http://dx.doi.org/10.3758/s13428-017-0864-z.

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16

Bremner, J. Gavin, Alan M. Slater, Uschi C. Mason, Jo Spring, and Scott P. Johnson. "Perception of occlusion by young infants: Must the occlusion event be congruent with the occluder?" Infant Behavior and Development 44 (August 2016): 240–48. http://dx.doi.org/10.1016/j.infbeh.2016.07.007.

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17

Wu, Jing-Long, and Kazuyoshi Tsukamoto. "Quantitative Measurement of Human Visual Characteristic on Depth Perception with Using Random-Dot Stimulus." Proceedings of the Human Factors and Ergonomics Society Annual Meeting 44, no. 21 (July 2000): 3–500. http://dx.doi.org/10.1177/154193120004402138.

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Human interactive characteristic between the binocular disparity and the occlusion for depth perception is measured with using random-dot stimulus. The experimental results suggested that if the binocular disparity is set at a proper value, the depth information is mainly obtained from the cue of the binocular disparity, and if the occlusion ratio is larger than some constant value the depth information is obtained from the cue of the occlusion. Based on the experimental results, we can find a method to make images with depth information in the Head Mounted Display (HMD) when the cues of the binocular disparity and the occlusion are concurrently used.

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18

Moreno, Francisco J., Vicente Luis, Francisco Salgado, Juan A. García, and Raúl Reina. "Visual Behavior and Perception of Trajectories of Moving Objects with Visual Occlusion." Perceptual and Motor Skills 101, no. 1 (August 2005): 13–20. http://dx.doi.org/10.2466/pms.101.1.13-20.

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Experienced athletes in sports with moving objects have shown greater skill when using visual information to anticipate the direction of a moving object than nonexperienced athletes of those sports. Studies have shown that expert athletes are more effective than novices in occlusion situations in the first stages of the sports sequence. In this study, 12 athletes with different competitive experience in sports with moving objects viewed a sequence of tennis ball launches with and without visual occlusion, launched by a ball-shooting machine toward different areas with respect to the participant's position. The relation among visual behavior, occlusion time, and the precision of the task is reviewed. The spot where the balls bounced was analysed by a digital camera and visual behavior by an Eye Tracking System. Analysis showed that the nonexperienced athletes made significantly more errors and were more variable in visual occlusion conditions. Participants had a stable visual search strategy.

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19

MENG Bo, 孟勃, 韩广良 HAN Guang-liang, and 毛雯蓓 MAO Wen-bei. "Grid Feature and Visualizition for Occlusion Perception in Object Tracking." ACTA PHOTONICA SINICA 42, no. 1 (2013): 98–103. http://dx.doi.org/10.3788/gzxb20134201.0098.

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20

Johnson, Scott P., J. Gavin Bremner, Alan M. Slater, Uschi C. Mason, and Kirsty Foster. "Young Infants' Perception of Unity and Form in Occlusion Displays." Journal of Experimental Child Psychology 81, no. 3 (March 2002): 358–74. http://dx.doi.org/10.1006/jecp.2002.2657.

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21

Vermeer, Jop, Leonardo Scandolo, and Elmar Eisemann. "Stochastic-Depth Ambient Occlusion." Proceedings of the ACM on Computer Graphics and Interactive Techniques 4, no. 1 (April 26, 2021): 1–15. http://dx.doi.org/10.1145/3451268.

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Ambient occlusion (AO) is a popular rendering technique that enhances depth perception and realism by darkening locations that are less exposed to ambient light (e.g., corners and creases). In real-time applications, screen-space variants, relying on the depth buffer, are used due to their high performance and good visual quality. However, these only take visible surfaces into account, resulting in inconsistencies, especially during motion. Stochastic-Depth Ambient Occlusion is a novel AO algorithm that accounts for occluded geometry by relying on a stochastic depth map, capturing multiple scene layers per pixel at random. Hereby, we efficiently gather missing information in order to improve upon the accuracy and spatial stability of conventional screen-space approximations, while maintaining real-time performance. Our approach integrates well into existing rendering pipelines and improves the robustness of many different AO techniques, including multi-view solutions.

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22

Stappers, P. J. "Forms Can Be Recognized from Dynamic Occlusion Alone." Perceptual and Motor Skills 68, no. 1 (February 1989): 243–51. http://dx.doi.org/10.2466/pms.1989.68.1.243.

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Direct and indirect theories of perception differ on whether form perception depends on higher order invariants or on features in the retinal image. The present paper describes a demonstration that an object can be recognized through a higher order pattern (dynamic occlusion) without any of the object's features being displayed. Stimuli consist of computer simulations of black wireframe objects moving in front of, and occluding, a random layout of point lights on a black background. In this way, no single videoframe of the stimuli displays any of the object's features, and motion of the amodal object in front of the light points is necessary for the form to become visible. The forms can also be recognized when isoluminous colours are used for background and point lights. Finally, it is noted that, if the observer can actively control the motion of the object, e.g., by moving a computer mouse, recognition is enhanced as in Gibson's (1962) experiment on active touch.

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23

Gillam, Barbara J. "Figure-Ground and Occlusion Depiction in Early Australian Aboriginal Bark Paintings." Leonardo 50, no. 3 (June 2017): 255–67. http://dx.doi.org/10.1162/leon_a_01423.

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Aboriginal painting has been largely treated as conceptual rather than perceptual and its visual impact little examined. In this article the author shows the perceptual skill and innovation demonstrated by Aboriginal bark painters in depicting figure-ground and occlusion. This has heuristic value for studying occlusion perception and adds visual meaning to the conceptual meaning of the paintings.

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24

Giaschi, Deborah, Christine Chapman, Kimberly Meier, Sathyasri Narasimhan, and David Regan. "The effect of occlusion therapy on motion perception deficits in amblyopia." Vision Research 114 (September 2015): 122–34. http://dx.doi.org/10.1016/j.visres.2015.05.015.

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25

Lin, Y., G. J. Andersen, and A. Saidpour. "A bayesian analysis of kinetic occlusion for 2-D shape perception." Journal of Vision 4, no. 8 (August 1, 2004): 664. http://dx.doi.org/10.1167/4.8.664.

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26

Liu, B., and C. M. Schor. "The effect of occlusion on amodal completion and surface slant perception." Journal of Vision 5, no. 8 (March 17, 2010): 576. http://dx.doi.org/10.1167/5.8.576.

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27

Mitchell, Donald E., Maurice Ptito, and Franco Lepore. "Depth Perception in Monocularly Deprived Cats Following Part-time Reverse Occlusion." European Journal of Neuroscience 6, no. 6 (June 1994): 967–72. http://dx.doi.org/10.1111/j.1460-9568.1994.tb00591.x.

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28

Liu, Fei, Shubo Zhou, Yunlong Wang, Guangqi Hou, Zhenan Sun, and Tieniu Tan. "Binocular Light-Field: Imaging Theory and Occlusion-Robust Depth Perception Application." IEEE Transactions on Image Processing 29 (2020): 1628–40. http://dx.doi.org/10.1109/tip.2019.2943019.

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29

Nagasaka, Yasuo, Koji Hori, and Yoshihisa Osada. "Perceptual Grouping in Pigeons." Perception 34, no. 5 (May 2005): 625–32. http://dx.doi.org/10.1068/p5402.

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Animal studies reveal that many species perceive partially occluded objects in the same way as do humans. Pigeons have been a notable exception. We re-investigated this anomaly of pigeon perception using a different approach from previous studies. With our method, we show that pigeons perceive occluded objects in the same manner as do other species. In addition, we report that pigeons can recognize perceptually transparent surfaces when the effect is induced by the same perceptual mechanisms as occlusion. These results give behavioral evidence that the perception of both occlusion and transparency is a common visual function shared by pigeons and humans, despite the structural differences between their visual systems.

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30

Subedi, S., and C. Shrestha. "Branch Retinal Arterial Occlusion." Kathmandu University Medical Journal 8, no. 4 (June 5, 2012): 423–25. http://dx.doi.org/10.3126/kumj.v8i4.6244.

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Retinal arterial occlusion is an ocular emergency in which visual prognosis is poor mostly due to late presentation of the patient and macular involvement. The casee described, in this report is ane incidence of Branch Retinal Arterial Occlusion in a 22 year old female with grade II Mitral Regurgitation. The patiente presented witha complaint of painless, diminution of vision in the right eyn. She alsod presented with perception of black shadow in the superior visual fiel n of the same eye5 for five days. There was no significant systemic ord personal history. Her visual acuity at presentation was 6/60 and 6/6 in the right and left eyes,y which did not improve with glasses or pin-hole. Anterior segment including papillary reaction was normal in both eyes while Fundus examination of the right eye revealed retinal whitening inside the inferotemporal vascular arcade that was encroaching foveolar avascular zone. Visual field defect was detected at superonasally inside arhade but Fundus Fluorescence Angiography was normal. An echoycardiograph revealed grade II Mitral Regurgitation. The patient was kept on observation and after two2 days of follow-up, vision in the right eye was improved to 6/6 unaided but visual field defect was remained same.http://dx.doi.org/10.3126/kumj.v8i4.6244 Kathmandu Univ Med J 2010;8(4):423-5

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31

Shuwairi, Sarah M., Clayton E. Curtis, and Scott P. Johnson. "Neural Substrates of Dynamic Object Occlusion." Journal of Cognitive Neuroscience 19, no. 8 (August 2007): 1275–85. http://dx.doi.org/10.1162/jocn.2007.19.8.1275.

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In everyday environments, objects frequently go out of sight as they move and our view of them becomes obstructed by nearer objects, yet we perceive these objects as continuous and enduring entities. Here, we used functional magnetic resonance imaging with an attentive tracking paradigm to clarify the nature of perceptual and cognitive mechanisms subserving this ability to fill in the gaps in perception of dynamic object occlusion. Imaging data revealed distinct regions of cortex showing increased activity during periods of occlusion relative to full visibility. These regions may support active maintenance of a representation of the target's spatiotemporal properties ensuring that the object is perceived as a persisting entity when occluded. Our findings may shed light on the neural substrates involved in object tracking that give rise to the phenomenon of object permanence.

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32

Cheng, Xiaohong, and Masanori Idesawa. "With occlusion by proximal surfaces, even without self-occlusion, continuously appearing and disappearing parts bring volume perception from motion." Optical Review 18, no. 4 (July 2011): 297–300. http://dx.doi.org/10.1007/s10043-011-0058-3.

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33

Navarro, Richard. "Effects of Ear Canal Occlusion and Masking on the Perception of Voice." Perceptual and Motor Skills 82, no. 1 (February 1996): 199–208. http://dx.doi.org/10.2466/pms.1996.82.1.199.

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This study examined the effect of ear canal occlusion and masking noise on four parameters of voice: (1) average fundamental frequency, (2) intensity in decibel (dB), (3) maximum fundamental frequency observed in a given sample (max), and (4) minimum fundamental frequency observed in a given sample (min). 12 normal hearing undergraduates produced the vowel /i/ ten times under conditions of unoccluded ear canal, ear canal occluded with a sound attenuating earplug, or masking noise. Other than a small (.73 dB) decrease in intensity, analysis showed no significant changes under the occluded condition; however, the masking condition showed statistically significant increases in the fundamental frequency, the intensity, and the maximum and minimum frequency as well as an increased range of frequencies.

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34

Brown, James M., and Christopher Koch. "Influences of closure, occlusion, and size on the perception of fragmented pictures." Perception & Psychophysics 53, no. 4 (July 1993): 436–42. http://dx.doi.org/10.3758/bf03206787.

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35

Brown, James M., and Christopher Koch. "Influences of Occlusion, Color, and Luminance on the Perception of Fragmented Pictures." Perceptual and Motor Skills 90, no. 3 (June 2000): 1033–44. http://dx.doi.org/10.2466/pms.2000.90.3.1033.

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36

Stein, J., and S. Fowler. "EFFECT OF MONOCULAR OCCLUSION ON VISUOMOTOR PERCEPTION AND READING IN DYSLEXIC CHILDREN." Lancet 326, no. 8446 (July 1985): 69–73. http://dx.doi.org/10.1016/s0140-6736(85)90179-5.

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37

Fiser, J., B. J. Scholl, and R. N. Aslin. "Perception of object trajectories during occlusion constrains statistical learning of visual features." Journal of Vision 4, no. 8 (August 1, 2004): 189. http://dx.doi.org/10.1167/4.8.189.

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38

MORENO, FRANCISCO J. "VISUAL BEHAVIOR AND PERCEPTION OF TRAJECTORIES OF MOVING OBJECTS WITH VISUAL OCCLUSION." Perceptual and Motor Skills 101, no. 5 (2005): 13. http://dx.doi.org/10.2466/pms.101.5.13-20.

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39

Tsirlin, I., L. M. Wilcox, and R. S. Allison. "Combining occlusion and disparity information: a computational model of stereoscopic depth perception." Journal of Vision 13, no. 9 (July 25, 2013): 1177. http://dx.doi.org/10.1167/13.9.1177.

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40

Strickland, Brent, and Brian J. Scholl. "Visual perception involves event-type representations: The case of containment versus occlusion." Journal of Experimental Psychology: General 144, no. 3 (2015): 570–80. http://dx.doi.org/10.1037/a0037750.

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41

Teichmann, Klaus D. "20/20 Vision After Central Retinal Artery Occlusion with No Light Perception." Annals Of Ophthalmology 35, no. 2 (2003): 138–40. http://dx.doi.org/10.1385/ao:35:2:138.

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42

Anderson, Barton L. "The role of occlusion in the perception of depth, lightness, and opacity." Psychological Review 110, no. 4 (2003): 785–801. http://dx.doi.org/10.1037/0033-295x.110.4.785.

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43

Sajko, Robert, and Zeljka Mihajlovic. "Fast Image-Based Ambient Occlusion IBAO." International Journal of Virtual Reality 10, no. 4 (January 1, 2011): 61–65. http://dx.doi.org/10.20870/ijvr.2011.10.4.2830.

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The quality of computer rendering and perception of realism greatly depend on the shading method used to implement the interaction of light with the surfaces of objects in a scene. Ambient occlusion (AO) enhances the realistic impression of rendered objects and scenes. Properties that make Screen Space Ambient Occlusion (SSAO) interesting for real-time graphics are scene complexity independence, and support for fully dynamic scenes. However, there are also important issues with current approaches: poor texture cache use, introduction of noise, and performance swings. In this paper, a straightforward solution is presented. Instead of a traditional, geometry-based sampling method, a novel, image-based sampling method is developed, coupled with a revised heuristic function for computing occlusion. Proposed algorithm harnessing GPU power improves texture cache use and reduces aliasing artifacts. Two implementations are developed, traditional and novel, and their comparison reveals improved performance and quality of the proposed algorithm.

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44

Lira, Ana de Lourdes Sá de, Joyce Pires Barros da Cunha, Rebeca Maria Vieira Pereira, Alice Rodrigues Santos, Maria Karen Vasconcelos Fontenele, and Ronaldo Carvalho Pinto de Almeida. "Association between maloclusion and self-perception of oral aesthetics in adolescents." Brazilian Journal of Oral Sciences 19 (May 5, 2020): e206711. http://dx.doi.org/10.20396/bjos.v19i0.8656711.

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Aim: To evaluate the aesthetic self-perception capacity of adolescents from public schools regarding the presence of oral alterations from malocclusions. Methods: Cross-sectional and quantitative study with 374 adolescents between 16 and 18 years old, belonging to public schools in the city of Parnaíba, Piauí. The adolescents were separated by gender (male and female) and examined for malocclusions. The problem identified for each participant was recorded for later comparison of the influence of its presence with aesthetic self-perception. Then, all adolescents, including those who demonstrated normal occlusion during the clinical evaluation, answered a questionnaire containing eight questions about their perception of their own smile and its impact on their interpersonal relationships. Self-perception was also analyzed by comparing the responses of those with normal occlusion with that of malocclusion individuals. Student's t-tests were used to verify if there was a difference between the groups. Results: The most prevalent malocclusions after clinical examination were midline deviations, crowding and diastemas, and the ones that most scored in the adolescents' perception were crowding, misalignment and diastemas. Conclusion: The adolescents were able to perceive the aesthetic alterations resulting from malocclusions, being determinants of dissatisfaction when smiling. They were not ashamed to smile, did not consider that the ideal smile would improve their self-esteem and that misaligned teeth would not interfere with flirting and interpersonal relationships.

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45

Davenport, P. W., W. A. Friedman, F. J. Thompson, and O. Franzen. "Respiratory-related cortical potentials evoked by inspiratory occlusion in humans." Journal of Applied Physiology 60, no. 6 (June 1, 1986): 1843–48. http://dx.doi.org/10.1152/jappl.1986.60.6.1843.

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It has long been recognized that humans can perceive respiratory loads. There have been several studies on the detection and psychophysical quantification of mechanical load perception. This investigation was designed to record cortical sensory neurogenic activity related to inspiratory mechanical loading in humans. Inspiration was periodically occluded in human subjects while the electroencephalographic (EEG) activity in the somatosensory region of the cerebral cortex was recorded. The onset of inspiratory mouth pressure (Pm) was used to initiate signal averaging of the EEG signals. Cortical evoked potentials elicited by inspiratory occlusions were observed when C3 and C alpha were referenced to CZ. This evoked potential was not observed with the control (unoccluded) breaths. There was considerable subject variability in the peak latencies that was related to the differences in the inspiratory drive, as measured by occlusion pressure (P0.1). The results of this study demonstrate that neurogenic activity can be recorded in the somatosensory region of the cortex that is related to inspiratory occlusions. The peak latencies are longer than analogous somatosensory evoked potentials elicited by stimulation of the hand and foot. It is hypothesized that a portion of this latency difference is related to the time required for the subject to generate sufficient inspiratory force to activate the afferents mediating the cortical response.

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Zhang, Qi, Masanori Idesawa, and Yutaka Sakaguchi. "Pantomime Effect and Sustaining Cues in the Perception of a 3-D Illusory Transparent Object with Binocular Viewing." Journal of Robotics and Mechatronics 9, no. 1 (February 20, 1997): 79–82. http://dx.doi.org/10.20965/jrm.1997.p0079.

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A new visual effect --- ""pantomime"" effect has been found in transparent object perception with binocular viewing. It is induced by the visual stimuli sustaining cues arranged in suitable relations. Sustaining cues played different roles in this effect according to their positions, they can be classified into three types: font-, side-, and back- sustaining cues. It was also found that this effect was closely related to occlusion perception; front-sustaining cues can be regarded as a kind of bulky occusion cues in opaque object perception. In addition, we show that several kinds of sustaining cues induce the perception of different kinds of illusory transparent objects.

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47

Liu, Lei, Scott B. Stevenson, and Clifton M. Schor. "Vergence Eye Movements Elicited by Stimuli without Corresponding Features." Perception 27, no. 1 (January 1998): 7–20. http://dx.doi.org/10.1068/p270007.

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We have observed quantitative depth perception with a dichoptic stimulus which possessed no contrast-defined binocular corresponding features (phantom stereogram). The depth perception can be the result of appreciation of a partial-occlusion situation depicted by the stimulus, or the result of activities of low-level disparity detectors which are capable of combining dissimilar local features in the stimulus. Although both mechanisms predict similar depth perception, they predict different vergence eye-movement outputs, especially in the vertical dimension. To identify the underlying mechanisms of the phantom stereopsis, we recorded vergence tracking eye movements to four types of dichoptic stimuli: (a) conventional stereogram with horizontal disparity (HD); (b) horizontal phantom stereogram (HP); (c) conventional stereogram with vertical disparity (VD); and (d) vertical phantom stereogram (VP). We found that HD, HP, and VD stimuli could elicit robust vergence tracking eye movements but VP stimulus could not. While the success of HP stimulus in eliciting vergence tracking may be explained by proximal vergence, the failure of VP stimulus in eliciting vergence tracking clearly indicates that phantom stereogram could not elicit coherent responses among low-level disparity detectors. Partial occlusion, therefore, has to play an important role in the depth perception from the phantom stereogram.

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48

Li, François-Xavier, and Michel Laurent. "Occlusion Rate of Ball Texture as a Source of Velocity Information." Perceptual and Motor Skills 81, no. 3 (December 1995): 871–80. http://dx.doi.org/10.2466/pms.1995.81.3.871.

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When a ball is rolling on the ground toward an observer, its elements of texture are successively occluded. The number of the elements of texture occluded per unit of time determines the occlusion rate. The aim of this study was to examine the role of the occlusion rate of ball texture and the velocity of the ball in the perception of the time remaining before the arrival. If the occlusion rate is used to perceive the time to arrival, then timing the initiation of movement should depend on occlusion rate. On the other hand, if the optical variable tau is exclusively used, then no variation is expected. 20 subjects were required to avoid balls rolling directly toward them. Three different ball textures and five ball velocities were used, leading to 10 different occlusion rates. The results showed that the timing of the initiation of the movement was not modified by variations of occlusion rate. However, the velocity of the avoidance movement increased with occlusion rate. The role of timing initiation and movement velocity in the control of the action are discussed, and it is suggested that occlusion rate is perceived and taken into account in the control of avoidance movements.

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Kollegger, Gerrit, Josef Wiemeyer, Marco Ewerton, and Jan Peters. "Perception and prediction of the putting distance of robot putting movements under different visual/viewing conditions." PLOS ONE 16, no. 4 (April 23, 2021): e0249518. http://dx.doi.org/10.1371/journal.pone.0249518.

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The purpose of this paper is to examine, whether and under which conditions humans are able to predict the putting distance of a robotic device. Based on the “flash-lag effect” (FLE) it was expected that the prediction errors increase with increasing putting velocity. Furthermore, we hypothesized that the predictions are more accurate and more confident if human observers operate under full vision (F-RCHB) compared to either temporal occlusion (I-RCHB) or spatial occlusion (invisible ball, F-RHC, or club, F-B). In two experiments, 48 video sequences of putt movements performed by a BioRob robot arm were presented to thirty-nine students (age: 24.49±3.20 years). In the experiments, video sequences included six putting distances (1.5, 2.0, 2.5, 3.0, 3.5, and 4.0 m; experiment 1) under full versus incomplete vision (F-RCHB versus I-RCHB) and three putting distances (2. 0, 3.0, and 4.0 m; experiment 2) under the four visual conditions (F-RCHB, I-RCHB, F-RCH, and F-B). After the presentation of each video sequence, the participants estimated the putting distance on a scale from 0 to 6 m and provided their confidence of prediction on a 5-point scale. Both experiments show comparable results for the respective dependent variables (error and confidence measures). The participants consistently overestimated the putting distance under the full vision conditions; however, the experiments did not show a pattern that was consistent with the FLE. Under the temporal occlusion condition, a prediction was not possible; rather a random estimation pattern was found around the centre of the prediction scale (3 m). Spatial occlusion did not affect errors and confidence of prediction. The experiments indicate that temporal constraints seem to be more critical than spatial constraints. The FLE may not apply to distance prediction compared to location estimation.

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Lindsey, David H., Bhavna Shroff, Caroline K. Carrico, James Dodd, and Steven J. Lindauer. "Orthodontists' and parents’ perception of finished occlusion and willingness to extend treatment time." American Journal of Orthodontics and Dentofacial Orthopedics 158, no. 6 (December 2020): 799–806. http://dx.doi.org/10.1016/j.ajodo.2019.10.022.

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