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Vision Research Jan 2021To calibrate stereoscopic depth from disparity our visual system must compensate for an object's egocentric location. Ideally, the perceived three-dimensional shape and...
To calibrate stereoscopic depth from disparity our visual system must compensate for an object's egocentric location. Ideally, the perceived three-dimensional shape and size of objects in visual space should be invariant with their location such that rigid objects have a consistent identity and shape. These percepts should be accurate enough to support both perceptual judgments and visually-guided interaction. This theoretical note reviews the relationship of stereoscopic depth constancy to the geometry of stereoscopic space and seemingly esoteric concepts like the horopter. We argue that to encompass the full scope of stereoscopic depth constancy, researchers need to consider not just distance but also direction, that is 3D egocentric location in space. Judgements of surface orientation need to take into account the shape of the horopter and the computation of metric depth (when tasks depend on it) must compensate for direction as well as distance to calibrate disparities. We show that the concept of the horopter underlies these considerations and that the relationship between depth constancy and the horopter should be more explicit in the literature.
Topics: Depth Perception; Humans; Judgment; Mathematics; Vision Disparity
PubMed: 33161145
DOI: 10.1016/j.visres.2020.10.003 -
Vision Research Apr 1999Many similarities exist between the perception of depth from binocular stereopsis and that from motion parallax. Moreover, Rogers (1984, cited in, Howard, I. P., &...
Many similarities exist between the perception of depth from binocular stereopsis and that from motion parallax. Moreover, Rogers (1984, cited in, Howard, I. P., & Rogers, B. J. (1995). Binocular vision and stereopsis. Oxford Claridon, New York.) suggests a relationship between an observer's ability to use disparity information and motion parallax information in a depth perception task. To more closely investigate this relationship, depth perception was studied in normal observers and amblyopic observers with poor stereo vision. As expected, amblyopic observers performed much worse than normal observers on depth discriminations requiring use of binocular disparity. However, amblyopic observers also performed much worse than normal observers on depth discriminations based on motion parallax. This result provides supporting evidence for a psychoanatomical link between the perception of depth from motion and the perception of depth from binocular disparity.
Topics: Amblyopia; Cues; Depth Perception; Humans; Motion Perception; Sensory Thresholds; Vision Disparity
PubMed: 10343851
DOI: 10.1016/s0042-6989(98)00235-1 -
Journal of Experimental Psychology.... Aug 1986The results of three experiments demonstrated that the visual system calibrates motion parallax according to absolute-distance information in processing depth. The...
The results of three experiments demonstrated that the visual system calibrates motion parallax according to absolute-distance information in processing depth. The parallax was created by yoking the relative movement of random dots displayed on a cathode-ray tube to the movements of the head. In Experiment 1, at viewing distances of 40 cm and 80 cm, observers reported the apparent depth produced by motion parallax equivalent to a binocular disparity of 0.47 degree. The mean apparent depth at 80 cm was 2.6 times larger than at 40 cm. In Experiment 2, again at viewing distances of 40 cm and 80 cm, observers adjusted the extent of parallax so that the apparent depth was 7.0 cm. The mean extent of parallax at 80 cm was 31% of that at 40 cm. In Experiment 3, distances ranged from 40 cm to 320 cm, and a wide range of parallax was used. As distance and parallax increased, the perception of a rigid three-dimensional surface was accompanied by rocking motion; perception of depth was replaced by perception of motion in some trials at 320 cm. Moreover, the mean apparent depths were proportional to the viewing distance at 40 cm and 80 cm but not at 160 cm and 320 cm.
Topics: Cues; Depth Perception; Humans; Motion Perception; Retina
PubMed: 2943861
DOI: 10.1037//0096-1523.12.3.331 -
Optometry and Vision Science : Official... Oct 1998To test the hypothesis that extraretinal cues related to vergence angle and lens accommodation are used to scale horizontal disparities for fixation distance.
PURPOSE
To test the hypothesis that extraretinal cues related to vergence angle and lens accommodation are used to scale horizontal disparities for fixation distance.
METHODS
Depth perception of random dot stereograms was studied in 10 healthy adult subjects with normal visual acuity by modifying retinal disparity, fixation distance, vergence angle, and accommodation. Statistical analysis was used to compare the data.
RESULTS
Depth perception increased with fixation distance. The increment of depth perception persisted even when horizontal retinal disparity was kept constant. The magnitude of depth perception was independent of vergence angle. Depth perception did not vary with changes in accommodation.
CONCLUSIONS
Extraretinal cues related to vergence angle and accommodation seem to be not necessary to scale horizontal disparities for viewing distance.
Topics: Accommodation, Ocular; Adult; Convergence, Ocular; Depth Perception; Humans; Reference Values; Vision Disparity; Vision Tests
PubMed: 9798214
DOI: 10.1097/00006324-199810000-00019 -
Current Biology : CB Jun 2017How does our brain use differences between the images in our two eyes, binocular disparities, to generate depth perception? New work shows that a type of neural network...
How does our brain use differences between the images in our two eyes, binocular disparities, to generate depth perception? New work shows that a type of neural network trained on natural binocular images can learn parameters that match key properties of visual cortex. Most information is conveyed by cells which sense differences between the two eyes' images.
Topics: Depth Perception; Vision Disparity; Vision, Binocular; Visual Cortex; Visual Perception
PubMed: 28633028
DOI: 10.1016/j.cub.2017.05.013 -
Cognitive Neuropsychiatry 2012Impaired depth perception, a fundamental aspect of early visual processing, has been shown in patients with schizophrenia suggesting a disturbance to magnocellular and...
INTRODUCTION
Impaired depth perception, a fundamental aspect of early visual processing, has been shown in patients with schizophrenia suggesting a disturbance to magnocellular and possibly parvocellular pathways. Despite some evidence showing visual-perceptive deficits in people with schizotypal personality traits (SPT), depth perception has not been evaluated in these subjects.
METHODS
12 clinically healthy schizotypy and 17 control participants were examined using a novel stereoscopic depth perception task. A mixed ANOVA design considered the Group (SPT/control) as independent factor, and trial Block (BD/BD+/BD-) and target Condition (SDSS/SDDS/DDSS/DDDS) were considered as repeated measures.
RESULTS
Schizotypal participants were not significantly different to controls on simple judgements of depth but demonstrated a subtle impairment in perceiving binocular depth when performing high difficulty judgements.
CONCLUSIONS
The presence of subtle depth perception problems in schizotypal subjects, similar but less marked than those of schizophrenia patients, may suggest a less pervasive disturbance of early information processing. If so, such deficits could be considered as innate neurological changes that may occur in people vulnerable for schizophrenia, thus with the potential to be a novel intermediate phenotype.
Topics: Adolescent; Depth Perception; Female; Humans; Judgment; Male; Neuropsychological Tests; Psychiatric Status Rating Scales; Schizophrenic Psychology; Schizotypal Personality Disorder; Young Adult
PubMed: 21722047
DOI: 10.1080/13546805.2011.576864 -
Journal of Vision Oct 2017Binocular disparity is represented by interocular cross-correlation of visual images in the striate and some extrastriate cortices. This correlation-based representation...
Binocular disparity is represented by interocular cross-correlation of visual images in the striate and some extrastriate cortices. This correlation-based representation produces reversed depth perception in a binocularly anticorrelated random-dot stereogram (aRDS) when it is accompanied by an adjacent correlated RDS (cRDS). Removal of the cRDS or spatial separation between the aRDS and cRDS abolishes reversed depth perception. However, how an immediate plane supports reversed depth perception is unclear. One possible explanation is that the correlation-based representation generates reversed depth based on the relative disparity between the aRDS and cRDS rather than the absolute disparity of the aRDS. Here, we psychophysically tested this hypothesis. We found that participants perceived reversed depth in an aRDS with zero absolute disparity when it was surrounded by a cRDS with nonzero absolute disparity (i.e., nonzero relative disparity), suggesting a role of relative disparity on the depth reversal. In addition, manipulation of the absolute disparities of the central aRDS and surrounding cRDS caused depth perception to reverse with respect to the depth of the surround. Further, depth reversal persisted after swapping the locations of the two RDSs. A model of relative-disparity encoding explains all these results. We conclude that reversed depth perception in aRDSs occurs in a relative frame of reference and suggest that the visual system contains correlation-based representation that encodes relative disparity.
Topics: Adult; Depth Perception; Female; Humans; Male; Photic Stimulation; Psychophysics; Reference Values; Vision Disparity; Vision, Binocular
PubMed: 29071354
DOI: 10.1167/17.12.17 -
Current Biology : CB Mar 2012A new study shows that, in vision, object blur can be a more accurate depth cue than stereo disparity.
A new study shows that, in vision, object blur can be a more accurate depth cue than stereo disparity.
Topics: Depth Perception; Fixation, Ocular; Humans; Male; Vision, Binocular
PubMed: 22401898
DOI: 10.1016/j.cub.2012.01.048 -
Perception 1993The plasticity of binocular depth perception was investigated. Six subjects wore left-right reversing spectacles continuously for 10 or 11 days. On looking through the...
The plasticity of binocular depth perception was investigated. Six subjects wore left-right reversing spectacles continuously for 10 or 11 days. On looking through the spectacles, the relation between the direction of physical depth (convex or concave) and the direction of binocular disparity (crossed or uncrossed) was reversed, but other depth cues did not change. When subjects observed stereograms through a haploscope and were asked to judge the direction of perceived depth, the directional relation between perceived depth and disparity was reversed both in the two line-contoured stereograms and in the random-dot stereogram in the middle of the wearing period, but the normal relation often returned late in the wearing period. When subjects observed two objects while wearing the spectacles and were asked which appeared the nearer, veridical depth perception increased as the wearing-time passed. These results indicate that the visual transformation reversing the direction of binocular disparity causes changes both in binocular stereopsis and in processes integrating different depth cues.
Topics: Depth Perception; Eyeglasses; Humans; Male; Photic Stimulation; Retina; Stereognosis; Vision Disparity; Vision, Binocular
PubMed: 8190599
DOI: 10.1068/p220971 -
First- and second-order contributions to depth perception in anti-correlated random dot stereograms.Scientific Reports Sep 2018The binocular energy model of neural responses predicts that depth from binocular disparity might be perceived in the reversed direction when the contrast of dots...
The binocular energy model of neural responses predicts that depth from binocular disparity might be perceived in the reversed direction when the contrast of dots presented to one eye is reversed. While reversed-depth has been found using anti-correlated random-dot stereograms (ACRDS) the findings are inconsistent across studies. The mixed findings may be accounted for by the presence of a gap between the target and surround, or as a result of overlap of dots around the vertical edges of the stimuli. To test this, we assessed whether (1) the gap size (0, 19.2 or 38.4 arc min) (2) the correlation of dots or (3) the border orientation (circular target, or horizontal or vertical edge) affected the perception of depth. Reversed-depth from ACRDS (circular no-gap condition) was seen by a minority of participants, but this effect reduced as the gap size increased. Depth was mostly perceived in the correct direction for ACRDS edge stimuli, with the effect increasing with the gap size. The inconsistency across conditions can be accounted for by the relative reliability of first- and second-order depth detection mechanisms, and the coarse spatial resolution of the latter.
Topics: Adolescent; Adult; Attention; Depth Perception; Female; Humans; Male; Models, Biological; Photic Stimulation; Vision Disparity; Vision, Binocular; Young Adult
PubMed: 30237535
DOI: 10.1038/s41598-018-32500-4