Effect of Pictorial Depth Cues, Binocular Disparity Cues and Motion Parallax Depth Cues on Lightness Perception in Three-Dimensional Virtual Scenes

Disparity tuning in visual cortex has been shown using a variety of stimulus types that contain stereoscopic depth cues. It is not known whether different stimuli yield similar disparity tuning curves. We studied whether cells in visual area V4 of the macaque show similar disparity tuning profiles when the same set of disparity values were tested using bars or dynamic random dot stereograms, which are among the most commonly used stimuli for this purpose. In a majority of V4 cells (61%), the shape of the disparity tuning profile differed significantly for the two stimulus types. The two sets of stimuli yielded statistically indistinguishable disparity tuning profiles for only a small minority (6%) of V4 cells. These results indicate that disparity tuning in V4 is stimulus-dependent. Given the fact that bar stimuli contain two-dimensional (2-D) shape cues, and the random dot stereograms do not, our results also indicate that V4 cells represent 2-D shape and binocular disparity in an interdependent fashion, revealing an unexpected complexity in the analysis of depth and three-dimensional shape.

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Border-ownership-dependent tilt aftereffect for shape defined by binocular disparity and motion parallax

10.1101/472076 ◽

2018 ◽

Author(s):

Reuben Rideaux ◽

William J Harrison

Keyword(s):

Binocular Disparity ◽

Motion Parallax ◽

Neural Systems ◽

Visual Object ◽

Access To Information ◽

Tilt Aftereffect ◽

Critical Function ◽

Depth Order ◽

Depth Cues ◽

Ground Segmentation

ABSTRACTDiscerning objects from their surrounds (i.e., figure-ground segmentation) in a way that guides adaptive behaviours is a fundamental task of the brain. Neurophysiological work has revealed a class of cells in the macaque visual cortex that may be ideally suited to support this neural computation: border-ownership cells (Zhou, Friedman, & von der Heydt, 2000). These orientation-tuned cells appear to respond conditionally to the borders of objects. A behavioural correlate supporting the existence of these cells in humans was demonstrated using two-dimensional luminance defined objects (von der Heydt, Macuda, & Qiu, 2005). However, objects in our natural visual environments are often signalled by complex cues, such as motion and depth order. Thus, for border-ownership systems to effectively support figure-ground segmentation and object depth ordering, they must have access to information from multiple depth cues with strict depth order selectivity. Here we measure in humans (of both sexes) border-ownership-dependent tilt aftereffects after adapting to figures defined by either motion parallax or binocular disparity. We find that both depth cues produce a tilt aftereffect that is selective for figure-ground depth order. Further, we find the effects of adaptation are transferable between cues, suggesting that these systems may combine depth cues to reduce uncertainty (Bülthoff & Mallot, 1988). These results suggest that border-ownership mechanisms have strict depth order selectivity and access to multiple depth cues that are jointly encoded, providing compelling psychophysical support for their role in figure-ground segmentation in natural visual environments.SIGNIFICANCE STATEMENTSegmenting a visual object from its surrounds is a critical function that may be supported by “border-ownership” neural systems that conditionally respond to object borders. Psychophysical work indicates these systems are sensitive to objects defined by luminance contrast. To effectively support figure-ground segmentation, however, neural systems supporting border-ownership must have access to information from multiple depth cues and depth order selectivity. We measured border-ownership-dependent tilt aftereffects to figures defined by either motion parallax or binocular disparity and found aftereffects for both depth cues. These effects were transferable between cues, but selective for figure-ground depth order. Our results suggest that the neural systems supporting figure-ground segmentation have strict depth order selectivity and access to multiple depth cues that are jointly encoded.

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Integration of texture and disparity cues to surface slant in dorsal visual cortex

Journal of Neurophysiology ◽

10.1152/jn.01055.2012 ◽

2013 ◽

Vol 110 (1) ◽

pp. 190-203 ◽

Cited By ~ 26

Author(s):

Aidan P. Murphy ◽

Hiroshi Ban ◽

Andrew E. Welchman

Keyword(s):

Single Neuron ◽

Binocular Disparity ◽

Three Dimensional ◽

Surface Orientation ◽

Cortical Circuits ◽

Depth Cues ◽

3D Objects ◽

Surface Slant ◽

Cortical Responses ◽

Multivariate Pattern

Reliable estimation of three-dimensional (3D) surface orientation is critical for recognizing and interacting with complex 3D objects in our environment. Human observers maximize the reliability of their estimates of surface slant by integrating multiple depth cues. Texture and binocular disparity are two such cues, but they are qualitatively very different. Existing evidence suggests that representations of surface tilt from each of these cues coincide at the single-neuron level in higher cortical areas. However, the cortical circuits responsible for 1) integration of such qualitatively distinct cues and 2) encoding the slant component of surface orientation have not been assessed. We tested for cortical responses related to slanted plane stimuli that were defined independently by texture, disparity, and combinations of these two cues. We analyzed the discriminability of functional MRI responses to two slant angles using multivariate pattern classification. Responses in visual area V3B/KO to stimuli containing congruent cues were more discriminable than those elicited by single cues, in line with predictions based on the fusion of slant estimates from component cues. This improvement was specific to congruent combinations of cues: incongruent cues yielded lower decoding accuracies, which suggests the robust use of individual cues in cases of large cue conflicts. These data suggest that area V3B/KO is intricately involved in the integration of qualitatively dissimilar depth cues.

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Dynamic Occlusion and Motion Parallax in Depth Perception

Perception ◽

10.1068/p170255 ◽

1988 ◽

Vol 17 (2) ◽

pp. 255-266 ◽

Cited By ~ 26

Author(s):

Hiroshi Ono ◽

Brian J Rogers ◽

Masao Ohmi ◽

Mika E Ono

Keyword(s):

Relative Motion ◽

Depth Perception ◽

Motion Parallax ◽

Three Dimensional ◽

Depth Order ◽

Depth Cues ◽

Small Depth ◽

Stationary Observer ◽

Depth Separation ◽

Condition B

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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Ambiguous Pictorial Depth Cues and Perceptions of Nonrigid Motion in the Three-Loop Figure

Perception ◽

10.1068/p231049 ◽

1994 ◽

Vol 23 (9) ◽

pp. 1049-1062

Author(s):

Jack Broerse ◽

Rongxin Li ◽

Roderick Ashton

Keyword(s):

Three Dimensional ◽

Nonrigid Motion ◽

Rigid Transformation ◽

Shape Constancy ◽

Depth Cues ◽

Pictorial Depth ◽

Rigidity Constraint ◽

Invariance Hypothesis ◽

Special Instance ◽

Classical Size

The three-loop figure is a two-dimensional (2-D) pattern that generates (mis)perceptions of nonrigid three-dimensional (3-D) structure when rotated about its centre. Such observations have been described as counterexamples to the principle whereby a moving object is presumed to be rigid, provided that a rigid interpretation is possible (ie the ‘rigidity constraint’). In the present investigation we demonstrated that stationary three-loop figures exhibit many of the classic properties of multistable/ambiguous figures, with any one of several possible 3-D configurations being reported at any one instant. Further investigation revealed that perceived nonrigidity during rotation was markedly reduced (and rigidity enhanced) when the figure was modified with static pictorial depth cues (eg shading, interposition). These cues had no effect on the overall proportion of time that observers reported 3-D organisations in stationary versions of the figure, but significantly reduced the frequency of perceptual reorganisation, and increased the duration for reporting a particular organisation. Since each of the perceived 3-D structures in a stationary ambiguous 2-D figure has a unique kinetic counterpart (ie rigid transformation), we attribute the nonrigid structure perceived when the figure rotates to the integration of these otherwise inconsistent kinetic components; and have further illustrated this with modified versions of a Penrose impossible triangle. Under kinetic versions of the classical size/distance invariance hypothesis, the rigidity constraint may be considered to represent a special instance of size/shape constancy, in which case counterexamples involving (mis)perceptions of nonrigid structure are comparable to other well-known exceptions to such principles of minimum object change (eg classical illusions).

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Human temporal coordination of visual and auditory events in virtual reality

Seeing and Perceiving ◽

10.1163/187847612x646532 ◽

2012 ◽

Vol 25 (0) ◽

pp. 31

Author(s):

Michiteru Kitazaki

Keyword(s):

Virtual Reality ◽

Temporal Order ◽

Binocular Disparity ◽

Color Change ◽

Motion Parallax ◽

Near Field ◽

Auditory Stimuli ◽

Visual Depth ◽

Virtual Reality Environment ◽

Depth Cues

Since the speed of sound is much slower than light, we sometimes hear a sound later than an accompanying light event (e.g., thunder and lightning at a far distance). However, Sugita and Suzuki (2003) reported that our brain coordinates a sound and its accompanying light to be perceived simultaneously within 20 m distance. Thus, the light accompanied with physically delayed sound is perceived simultaneously with the sound in near field. We aimed to test if this sound–light coordination occurs in a virtual-reality environment and investigate effects of binocular disparity and motion parallax. Six naive participants observed visual stimuli on a 120-inch screen in a darkroom and heard auditory stimuli from a headphone. A ball was presented in a textured corridor and its distance from the participant was varied from 3–20 m. The ball changed to be in red before or after a short (10 ms) white noise (time difference: −120, −60, −30, 0, +30, +60, +120 ms), and participants judged temporal order of the color-change and the sound. We varied visual depth cues (binocular disparity and motion parallax) in the virtual-reality environment, and measured the physical delay at which visual and auditory events were perceived simultaneously. In terms of the results, we did not find sound–light coordination without binocular disparity or motion parallax, but found it with both cues. These results suggest that binocular disparity and motion parallax are effective for sound–light coordination in virtual-reality environment, and richness of depth cues are important for the coordination.

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Judgments of Azimuth and Elevation as a Function of Monoscopic and Binocular Depth Cues Using a Perspective Display

Human Factors The Journal of the Human Factors and Ergonomics Society ◽

10.1518/001872095779049453 ◽

1995 ◽

Vol 37 (1) ◽

pp. 173-181 ◽

Cited By ~ 34

Author(s):

Woodrow Barfield ◽

Craig Rosenberg

Keyword(s):

Spatial Information ◽

Binocular Disparity ◽

Three Dimensional ◽

Stereoscopic Display ◽

Absolute Value ◽

Depth Cues ◽

Depth Cue ◽

Three Dimensional Display ◽

The Difference ◽

Binocular Depth

The purpose of this study was to investigate the use of three-dimensional display formats for judgments of spatial information using an exocentric frame of reference. Eight subjects judged the azimuth and elevation that separated two computer-generated objects using either a perspective or stereoscopic display. Errors, which consisted of the difference in absolute value between the estimated and actual azimuth or elevation, were analyzed as the response variable. The data indicated that the stereoscopic display resulted in more accurate estimates of elevation, especially for images aligned approximately orthogonally to the viewing vector. However, estimates of relative azimuth direction were not improved by use of the stereoscopic display. Furthermore, it was shown that the effect of compression resulting from a 45--deg computer graphics eye point elevation produced a response bias that was symmetrical around the horizontal plane of the reference cube, and that the depth cue of binocular disparity provided by the stereoscopic display reduced the magnitude of the compression errors. Implications of the results for the design of spatial displays are discussed.

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Simultaneous and Successive Contrast Effects in the Perception of Depth from Motion-Parallax and Stereoscopic Information

Perception ◽

10.1068/p110247 ◽

1982 ◽

Vol 11 (3) ◽

pp. 247-262 ◽

Cited By ~ 67

Author(s):

Maureen Graham ◽

Brian Rogers

Keyword(s):

Contrast Effect ◽

Binocular Disparity ◽

Motion Parallax ◽

Three Dimensional ◽

Vertical Surface ◽

Test Surface ◽

Depth Information ◽

Apparent Depth ◽

Contrast Effects ◽

Inducing Surface

Prolonged inspection of a three-dimensional corrugated surface resulted in a successive contrast effect, or aftereffect, of depth, whereby a subsequently-viewed physically-flat test surface appeared to be corrugated in depth with the opposite phase to the adapting surface. The aftereffect occurred both when the depth was specified by motion parallax, in the absence of all other sources of depth information, and when it was specified solely by stereoscopic information. The depth aftereffect was measured by ‘nulling’ the apparent depth in the test surface with physical relative motion or binocular disparity until the test surface appeared flat. Up to 70% of the depth in the adapting surface was necessary to null the aftereffect. Simultaneous contrast effects in the perception of three-dimensional surfaces were used to investigate the spatial interactions that exist in the processing of motion-parallax and stereoscopic information. A physically vertical surface appeared to slope in depth in the opposite direction to the slope of a surrounding surface. In this case up to 50% of the slope of the inducing surface was necessary to null the contrast effect. Similar results were again obtained for motion-parallax and stereoscopic depth.

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