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Measuring Sensitivity to Viewpoint Change with and without Stereoscopic Cues
Published on: December 4, 2013
Coarse-fine dichotomies in human stereopsis
Laurie M Wilcox1, Robert S Allison
1Department of Psychology, Centre for Vision Research, 4700 Keele St., North York Ontario, Canada M3J1P3. lwilcox@yorku.ca
Vision Research
|June 13, 2009
Summary
This review examines how the brain processes visual depth perception from different levels of image disparity. It explores whether distinct neural mechanisms handle small versus large disparities and first- versus second-order visual stimuli.
Area of Science:
- Neuroscience
- Vision Science
- Cognitive Psychology
Background:
- Depth perception from large disparities, even beyond the fusion limit, is a well-established phenomenon.
- Diplopic stimuli, or images seen as double, can reliably evoke depth percepts.
- Existing research suggests potential dichotomies in disparity processing based on magnitude (small vs. large) and stimulus order (1st vs. 2nd).
Purpose of the Study:
- To review the literature on depth perception across the full spectrum of visual disparity.
- To evaluate the congruence between proposed dichotomies in disparity processing.
- To identify outstanding questions and areas for future research in depth perception.
Main Methods:
- Comprehensive literature review of studies on visual disparity processing.
- Analysis of research investigating depth percepts from both small and large disparities.
- Examination of studies differentiating between first-order and second-order stimulus processing.
Main Results:
- Reliable depth percepts are achievable even with very large visual disparities.
- Evidence suggests distinct neural mechanisms may underlie the processing of small versus large disparities.
- A dichotomy between first- and second-order stimulus processing is also proposed in visual perception research.
Conclusions:
- The review aims to clarify how different proposed dichotomies in disparity processing relate to each other.
- Understanding these relationships is crucial for a unified model of depth perception.
- Further research is needed to resolve inconsistencies and fully elucidate the neural underpinnings of depth percepts.
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