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PloS One 2022Past work has suggested that perception of object distances in natural scenes depends on the environmental surroundings, even when the physical object distance remains...
Past work has suggested that perception of object distances in natural scenes depends on the environmental surroundings, even when the physical object distance remains constant. The cue bases for such effects remain unclear and are difficult to study systematically in real-world settings, given the challenges in manipulating large environmental features reliably and efficiently. Here, we used rendered scenes and crowdsourced data collection to address these challenges. In 4 experiments involving 452 participants, we investigated the effect of room width and depth on egocentric distance judgments. Targets were placed at distances of 2-37 meters in rendered rooms that varied in width (1.5-40 meters) and depth (6-40 meters). We found large and reliable effects of room width: Average judgments for the farthest targets in a 40-meter-wide room were between 16-33% larger than for the same target distances seen in a 1.5-meter-wide hallway. Egocentric distance cues and focal length were constant across room widths, highlighting the role of environmental context in judging distances in natural scenes. Obscuring the fine-grained ground texture, per se, is not primarily responsible for the width effect, nor does linear perspective play a strong role. However, distance judgments tended to decrease when doors and/or walls obscured more distant regions of the scene. We discuss how environmental features may be used to calibrate relative distance cues for egocentric distance judgments.
Topics: Cues; Distance Perception; Environment; Female; Humans; Judgment; Male
PubMed: 35143537
DOI: 10.1371/journal.pone.0263497 -
Anatomical Record (Hoboken, N.J. : 2007) Mar 2022
From specialized skin to sensing whiskers to unique depth perception mechanisms to novel eyes and much, much more: The distinctive ways marine mammals interact with their world are explored in a Special Issue of the The Anatomical Record.
Topics: Animals; Cetacea; Depth Perception; Touch; Touch Perception; Vibrissae
PubMed: 35146950
DOI: 10.1002/ar.24866 -
Scientific Reports Jun 2023Knowing where objects are relative to us implies knowing where we are relative to the external world. Here, we investigated whether space perception can be influenced by...
Knowing where objects are relative to us implies knowing where we are relative to the external world. Here, we investigated whether space perception can be influenced by an experimentally induced change in perceived self-location. To dissociate real and apparent body positions, we used the full-body illusion. In this illusion, participants see a distant avatar being stroked in virtual reality while their own physical back is simultaneously stroked. After experiencing the discrepancy between the seen and the felt location of the stroking, participants report a forward drift in self-location toward the avatar. We wondered whether this illusion-induced forward drift in self-location would affect where we perceive objects in depth. We applied a psychometric measurement in which participants compared the position of a probe against a reference sphere in a two-alternative forced choice task. We found a significant improvement in task performance for the right visual field, indicated by lower just-noticeable differences, i.e., participants were better at judging the differences of the two spheres in depth. Our results suggest that the full-body illusion is able to facilitate depth perception at least unilaterally, implying that depth perception is influenced by perceived self-location.
Topics: Humans; Illusions; Differential Threshold; Emotions; Physical Examination; Stroke; Depth Perception
PubMed: 37386091
DOI: 10.1038/s41598-023-37715-8 -
Journal of Vision Mar 2021Motion perception is a critical function of the visual system. In a three-dimensional environment, multiple sensory cues carry information about an object's motion...
Motion perception is a critical function of the visual system. In a three-dimensional environment, multiple sensory cues carry information about an object's motion trajectory. Previous work has quantified the contribution of binocular motion cues, such as interocular velocity differences and changing disparities over time, as well as monocular motion cues, such as size and density changes. However, even when these cues are presented in concert, observers will systematically misreport the direction of motion-in-depth. Although in the majority of laboratory experiments head position is held fixed using a chin or head rest, an observer's head position is subject to involuntary small movements under real-world viewing conditions. Here, we considered the potential impact of such "head jitter" on motion-in-depth perception. We presented visual stimuli in a head-mounted virtual reality device that facilitated low latency head tracking and asked observers to judge 3D object motion. We found performance improved when we updated the visual display consistent with the small changes in head position. When we disrupted or delayed head movement-contingent updating of the visual display, the proportion of motion-in-depth misreports again increased, reflected in both a reduction in sensitivity and an increase in bias. Our findings identify a critical function of head jitter in visual motion perception, which has been obscured in most (head-fixed and non-head jitter contingent) laboratory experiments.
Topics: Cues; Depth Perception; Head Movements; Humans; Imaging, Three-Dimensional; Motion Perception; Virtual Reality; Vision, Binocular
PubMed: 33687429
DOI: 10.1167/jov.21.3.12 -
Journal of Vision Oct 2023Occlusion, or interposition, is one of the strongest and best-known pictorial cues to depth. Furthermore, the successive occlusions of previous objects by newly...
Occlusion, or interposition, is one of the strongest and best-known pictorial cues to depth. Furthermore, the successive occlusions of previous objects by newly presented objects produces an impression of increasing depth. Although the perceived motion associated with this illusion has been studied, the depth percept has not. To investigate, participants were presented with two piles of disks with one always static and the other either a static pile or a stacking pile where a new disk was added every 200 ms. We found static piles with equal number of disks appeared equal in height. In contrast, the successive presentation of disks in the stacking condition appeared to enhance the perceived height of the stack-fewer disks were needed to match the static pile. Surprisingly, participants were also more precise when comparing stacking versus static piles of disks. Reversing the stacking by removing rather than adding disks reversed the bias and degraded precision. In follow-up experiments, we used nonoverlapping static and dynamic configurations to show that the effects are not due to simple differences in perceived numerosity. In sum, our results show that successive occlusions generate a greater sense of height than occlusion alone, and we posit that dynamic occlusion may be an underappreciated source of depth information.
Topics: Humans; Depth Perception; Illusions; Cues; Motion Perception
PubMed: 37796523
DOI: 10.1167/jov.23.12.2 -
Vision Research Sep 2022Stereoscopic depth has a mixed record as a guiding attribute in visual attention. Visual search can be efficient if the target lies at a unique depth; whereas automatic...
Stereoscopic depth has a mixed record as a guiding attribute in visual attention. Visual search can be efficient if the target lies at a unique depth; whereas automatic segmentation of search arrays into different depth planes does not appear to be pre-attentive. These prior findings describe bottom-up, stimulus-driven depth guidance. Here, we ask about the top-down selection of depth information. To assess the ability to direct attention to specific depth planes, Experiment 1 used the centroid judgment paradigm which permits quantitative measures of selective processing of items of different depths or colors. Experiment 1 showed that a subset of observers could deploy specific attention filters for each of eight depth planes, suggesting that at least some observers can direct attention to a specific depth plane quite precisely. Experiment 2 used eight depth planes in a visual search experiment. Observers were encouraged to guide their attention to far or near depth planes with an informative but imperfect cue. The benefits of this probabilistic cue were small. However, this may not be a specific problem with guidance by stereoscopic depth. Equivalently poor results were obtained with color. To check and prove that depth guidance in search is possible, Experiment 3 presented items in only two depth planes. In this case, information about the target depth plane allows observers to search more efficiently, replicating earlier work. We conclude that top-down guidance by stereoscopic depth is possible but that it is hard to apply the full range of our stereoscopic ability in search.
Topics: Depth Perception; Humans; Judgment
PubMed: 35576843
DOI: 10.1016/j.visres.2022.108061 -
Vision Research Jan 2022In previous studies using VR, we found evidence that 3D shape estimation agrees to a superadditivity rule of depth-cue combination, by which adding depth cues leads to...
In previous studies using VR, we found evidence that 3D shape estimation agrees to a superadditivity rule of depth-cue combination, by which adding depth cues leads to greater perceived depth and, in principle, to depth overestimation. Superadditivity can be quantitatively accounted for by a normative theory of cue integration, via adapting a model termed Intrinsic Constraint (IC). As for its qualitative nature, it remains unclear whether superadditivity represents the genuine readout of depth-cue integration, as predicted by IC, or alternatively a byproduct of artificial virtual displays, because they carry flatness cues that can bias depth estimates in a Bayesian fashion, or even just a way for observers to express that a scene "looks deeper" with more depth cues by explicitly inflating their depth judgments. In the present study, we addressed this question by testing whether the IC model's prediction of superadditivity generalizes to real world settings. We asked participants to judge the perceived 3D shape of cardboard prisms through a matching task. To control for the potential interference of explicit reasoning, we also asked participants to reach-to-grasp the same objects and we analyzed the in-flight grip size throughout the reaching. We designed a novel technique to carefully control binocular and monocular 3D cues independently, allowing to add or remove depth information seamlessly. Even with real objects, participants exhibited a clear superadditivity effect in both tasks. Furthermore, the magnitude of this effect was accurately predicted by the IC model. These results confirm that superadditivity is an inherent feature of depth estimation.
Topics: Bayes Theorem; Bias; Cues; Depth Perception; Hand Strength; Humans; Vision, Binocular
PubMed: 34757304
DOI: 10.1016/j.visres.2021.107961 -
Perception Sep 2023The origin of depth in Panum's limiting case is unclear at present, so we investigated the depth perception mechanism using a triangle type of Panum's stimulus with a...
The origin of depth in Panum's limiting case is unclear at present, so we investigated the depth perception mechanism using a triangle type of Panum's stimulus with a slant effect and clear criterion. Experiment 1 explored whether participants can correctly perceive fixation and nonfixation features using the fixation point and quick representation of stimuli, then examined whether participants' depth judgments supported double fusion or single fusion. The results of Experiment 1 showed that participants could correctly perceive the depth of fixation and nonfixation features. That is, it supported double fusion. In Experiment 2, we examined whether the depth perceived by observers comes from depth contrast. The results of Experiment 2 showed that the depth of the two features perceived after binocular fusion did not originate from the depth contrast. The findings suggest that the depth perception mechanism of Panum's limiting case is more likely to be double fusion.
Topics: Depth Perception; Vision Disparity; Humans; Fixation, Ocular; Photic Stimulation; Models, Neurological; Reproducibility of Results; Male; Female; Young Adult; Adult; Analysis of Variance; Contrast Sensitivity
PubMed: 37408435
DOI: 10.1177/03010066231177513 -
Journal of Vision Dec 2022Individuals with macular degeneration typically lose vision in the central region of one or both eyes. A binocular scotoma occurs when vision loss occurs in overlapping...
Individuals with macular degeneration typically lose vision in the central region of one or both eyes. A binocular scotoma occurs when vision loss occurs in overlapping locations in both eyes, but stereopsis is impacted even in the non-overlapping region wherever the visual field in either eye is affected. We used a novel stereoperimetry protocol to measure local stereopsis across the visual field (up to 25° eccentricity) to determine how locations with functional stereopsis relate to the scotomata in the two eyes. Participants included those with monocular or binocular scotomata and age-matched controls with healthy vision. Targets (with or without depth information) were presented on a random dot background. Depth targets had true binocular disparity of 20' (crossed), whereas non-depth targets were defined by monocular cues such as contrast and dot density. Participants reported target location and whether it was in depth or flat. Local depth sensitivity (d') estimates were then combined to generate a stereopsis map. This stereopsis map was compared to the union of the monocular microperimetry estimates that mapped out the functional extent of the scotoma in each eye. The "union" prediction aligned with residual stereopsis, showing impaired stereopsis within this region and residual stereopsis outside this region. Importantly, the stereoblind region was typically more extensive than the binocular scotoma defined by the intersection (overlap) of the scotomata. This explains why individuals may have intact binocular visual fields but be severely compromised in tasks of daily living that benefit from stereopsis, such as eye-hand coordination and navigation.
Topics: Humans; Vision, Binocular; Scotoma; Depth Perception; Vision Disparity; Macular Degeneration
PubMed: 36580297
DOI: 10.1167/jov.22.13.7 -
Vision Research Aug 2024Rectangularity and perpendicularity of contours are important properties of 3D shape for the visual system and the visual system can use them asa prioriconstraints for... (Review)
Review
Rectangularity and perpendicularity of contours are important properties of 3D shape for the visual system and the visual system can use them asa prioriconstraints for perceivingshape veridically. The presentarticle provides a comprehensive review ofpriorstudiesofthe perception of rectangularity and perpendicularity anditdiscussestheir effects on3D shape perception from both theoretical and empiricalapproaches. It has been shown that the visual system is biased to perceive a rectangular 3D shape from a 2D image. We thought that this bias might be attributable to the likelihood of a rectangular interpretation but this hypothesis is not supported by the results of our psychophysical experiment. Note that the perception ofa rectangular shape cannot be explained solely on the basis of geometry. A rectangular shape is perceived from an image that is inconsistent with a rectangular interpretation. To address thisissue, we developed a computational model that can recover a rectangular shape from an image of a parallelopiped. The model allows the recovered shape to be slightly inconsistent so that the recovered shape satisfies the a priori constraints of maximum compactness and minimal surface area. This model captures someof thephenomenaassociated withthe perception of the rectangular shape that were reported inpriorstudies. This finding suggests that rectangularity works for shape perception by incorporatingitwith someadditionalconstraints.
Topics: Humans; Form Perception; Psychophysics; Depth Perception; Pattern Recognition, Visual; Photic Stimulation
PubMed: 38772272
DOI: 10.1016/j.visres.2024.108433