-
Psychological Review Apr 2014Humans can obtain an unambiguous perception of depth and 3-dimensionality with 1 eye or when viewing a pictorial image of a 3-dimensional scene. However, the perception... (Review)
Review
Humans can obtain an unambiguous perception of depth and 3-dimensionality with 1 eye or when viewing a pictorial image of a 3-dimensional scene. However, the perception of depth when viewing a real scene with both eyes is qualitatively different: There is a vivid impression of tangible solid form and immersive negative space. This perceptual phenomenon, referred to as "stereopsis," has been among the central puzzles of perception since the time of da Vinci. After Wheatstone's invention of the stereoscope in 1838, stereopsis has conventionally been explained as a byproduct of binocular vision or visual parallax. However, this explanation is challenged by the observation that the impression of stereopsis can be induced in single pictures under monocular viewing. Here I propose an alternative hypothesis that stereopsis is a qualitative visual experience related to the perception of egocentric spatial scale. Specifically, the primary phenomenal characteristic of stereopsis (the impression of "real" separation in depth) is proposed to be linked to the precision with which egocentrically scaled depth (absolute depth) is derived. Since conscious awareness of this precision could help guide the planning of motor action, the hypothesis provides a functional account for the important secondary phenomenal characteristics associated with stereopsis: the impression of interactability and realness. By linking stereopsis to a generic perceptual attribute, rather than a specific cue, it provides a potentially more unified account of the variation of stereopsis in real scenes and pictures and a basis for understanding why we can perceive depth in pictures despite conflicting visual signals.
Topics: Awareness; Depth Perception; Distance Perception; Humans; Optical Illusions; Orientation; Pattern Recognition, Visual; Psychological Theory; Psychophysics; Vision Disparity
PubMed: 24730596
DOI: 10.1037/a0035233 -
Neuron Dec 1999Physiological, computational, and psychophysical studies of stereopsis have assumed that the perceived surface structure of binocularly viewed images is primarily... (Clinical Trial)
Clinical Trial Randomized Controlled Trial
Physiological, computational, and psychophysical studies of stereopsis have assumed that the perceived surface structure of binocularly viewed images is primarily specified by the pattern of binocular disparities in the two eyes' views. A novel set of stereoscopic phenomena are reported that demonstrate the insufficiency of this view. It is shown that the visual system computes the contrast relationships along depth discontinuities to infer the depth, lightness, and opacity of stereoscopically viewed surfaces. A novel theoretical framework is introduced to explain these results. It is argued that the visual system contains mechanisms that enforce two principles of scene interpretation: a generic view principle that determines qualitative scene geometry, and anchoring principles that determine how image data are quantitatively partitioned between different surface attributes.
Topics: Algorithms; Brain Mapping; Depth Perception; Humans; Photic Stimulation; Vision Disparity; Vision, Monocular; Visual Perception
PubMed: 10624955
DOI: 10.1016/s0896-6273(00)81039-9 -
PloS One 2014Images projected onto the retinas of our two eyes come from slightly different directions in the real world, constituting binocular disparity that serves as an important...
Images projected onto the retinas of our two eyes come from slightly different directions in the real world, constituting binocular disparity that serves as an important source for depth perception - the ability to see the world in three dimensions. It remains unclear whether the integration of disparity cues into visual perception depends on the conscious representation of stereoscopic depth. Here we report evidence that, even without inducing discernible perceptual representations, the disparity-defined depth information could still modulate the visual processing of 3D objects in depth-irrelevant aspects. Specifically, observers who could not discriminate disparity-defined in-depth facing orientations of biological motions (i.e., approaching vs. receding) due to an excessive perceptual bias nevertheless exhibited a robust perceptual asymmetry in response to the indistinguishable facing orientations, similar to those who could consciously discriminate such 3D information. These results clearly demonstrate that the visual processing of biological motion engages the disparity cues independent of observers' depth awareness. The extraction and utilization of binocular depth signals thus can be dissociable from the conscious representation of 3D structure in high-level visual perception.
Topics: Depth Perception; Female; Form Perception; Humans; Male; Motion Perception; Orientation; Photic Stimulation; Vision Disparity; Vision, Binocular; Young Adult
PubMed: 24586622
DOI: 10.1371/journal.pone.0089238 -
Perception 2009
Topics: Depth Perception; History, 19th Century; Humans; Optical Illusions; Paintings; Vision Disparity
PubMed: 19662939
DOI: 10.1068/p3805ed -
Human Factors Dec 1992This paper reviews much of the basic literature on stereopsis for the purpose of providing information about the ability of humans to utilize stereoscopic information... (Review)
Review
This paper reviews much of the basic literature on stereopsis for the purpose of providing information about the ability of humans to utilize stereoscopic information under operational conditions. This review is organized around five functional topics that may be important for the design of many stereoscopic display systems: geometry of stereoscopic depth perception, visual persistence, perceptual interaction among stereoscopic stimuli, neurophysiology of stereopsis, and theoretical considerations. The paper concludes with the presentation of several basic ideas related to the design of stereoscopic displays.
Topics: Animals; Depth Perception; Humans; Neurons; Retina; Vision Disparity; Vision, Binocular; Visual Cortex; Visual Pathways
PubMed: 1292991
DOI: 10.1177/001872089203400603 -
Nature Nov 1995The view of the world from different perspectives provided by the two eyes is used by the human visual system to compute the relative distances and solid shapes of...
The view of the world from different perspectives provided by the two eyes is used by the human visual system to compute the relative distances and solid shapes of objects. However, the traditional theory of binocular disparity takes little account of the fact that a moving target will stimulate many different sets of disparate points in the two eyes with a range of temporal delays. Here we show that stereoacuity for periodic grating is not degraded by velocities of up to 640 degrees s-1 provided that they do not move at a greater rate than 30 cycles s-1. The minimum detectable spatial phase difference between the eyes was equivalent to a spatial phase difference of about 5 degrees and an interocular temporal delay as small as 450 microseconds. We suggest that stereopsis for moving targets is accomplished by neurons having a spatial-temporal phase shift in their receptive fields between the eyes.
Topics: Depth Perception; Differential Threshold; Humans; Motion Perception
PubMed: 7477373
DOI: 10.1038/378380a0 -
Eye (London, England) May 2024
Topics: Humans; Lenses, Intraocular; Lens Implantation, Intraocular; Depth Perception; Prosthesis Design
PubMed: 38580744
DOI: 10.1038/s41433-024-03045-w -
Vision Research Jul 2010Previous research (Brooks & Gillam, 2006) has found that temporal interocular unmatched (IOUM) features generate a perception of subjective contours and can result in a...
Previous research (Brooks & Gillam, 2006) has found that temporal interocular unmatched (IOUM) features generate a perception of subjective contours and can result in a perception of quantitative depth. In the present study we examine in detail the factors important for quantitative depth perception from IOUM features. In Experiments 1 and 2 observers were shown temporal IOUM features based on three dots that disappeared behind an implicit surface. Subjects reported a perception of a subjective surface and were able to perceive qualitative depth. In Experiments 3 and 4 metrical depth was perceived when binocular disparity features were added to the display. These results suggest that quantitative depth from IOUM information is perceived when binocular matched information is present in regions adjacent to the surface. In addition, the perceived depth of the subjective surface decreased with an increase in the width of the subjective surface suggesting a limitation in the propagation of quantitative depth to surface regions where qualitative depth information is available.
Topics: Depth Perception; Humans; Photic Stimulation; Vision Disparity; Vision, Binocular
PubMed: 20493899
DOI: 10.1016/j.visres.2010.05.017 -
Vision Research Apr 2021Luminance contrast is one of the key factors in the visibility of objects in the world around us. Previous work has shown that the perceived depth from binocular...
Luminance contrast is one of the key factors in the visibility of objects in the world around us. Previous work has shown that the perceived depth from binocular disparity depends profoundly on the luminance contrast of the image. This dependence cannot be explained by existing disparity models, such as the well-established disparity energy model, because they predict no effect of luminance contrast on depth perception. Here, we develop a model for disparity processing that incorporates contrast normalization of the neural response into the disparity energy model to account for the contrast dependence of perceived depth from disparity. Our model contains an array of disparity channels, each with a different disparity selectivity. The binocular images are first processed by the left- and right-eye receptive fields of each channel. The outputs of the two receptive fields are combined linearly as the excitatory disparity sensitivity and then fed into a nonlinear contrast gain control mechanism. The perceived depth is determined by the weighted average of all the disparity channels that respond to the binocular images. This model provides the first analytic account of how luminance contrast affects perceived depth from disparity.
Topics: Depth Perception; Humans; Vision Disparity; Vision, Binocular
PubMed: 33556821
DOI: 10.1016/j.visres.2020.12.008 -
Journal of Vision Aug 2013A key goal of visual processing is to develop an understanding of the three-dimensional layout of the objects in our immediate vicinity from the variety of incomplete...
A key goal of visual processing is to develop an understanding of the three-dimensional layout of the objects in our immediate vicinity from the variety of incomplete and noisy depth cues available to the eyes. Binocular disparity is one of the dominant depth cues, but it is often sparse, being definable only at the edges of uniform surface regions, and visually resolvable only where the edges have a horizontal disparity component. To understand the full 3D structure of visual objects, our visual system has to perform substantial surface interpolation across unstructured visual space. This interpolation process was studied in an eight-spoke depth spreading configuration corresponding to that used in the neon color spreading effect, which generates a strong percept of a sharp contour extending through empty space from the disparity edges within the spokes. Four hypotheses were developed for the form of the depth surface induced by disparity in the spokes defining an incomplete disk in depth: low-level local (isotropic) depth propagation, mid-level linear (anisotropic) depth-contour interpolation or extrapolation, and high-level (anisotropic) figural depth propagation of a disk figure in depth. Data for both perceived depth and position of the perceived contour clearly rejected the first three hypotheses and were consistent with the high-level figural hypothesis in both uniform disparity and slanted disk configurations. We conclude that depth spreading through empty visual space is an accurately quantifiable perceptual process that propagates depth contours anisotropically along their length and is governed by high-level figural properties of 3D object structure.
Topics: Cues; Depth Perception; Form Perception; Humans; Imaging, Three-Dimensional; Photic Stimulation; Space Perception; Vision Disparity
PubMed: 23946433
DOI: 10.1167/13.10.7