ArticleProceedings of the National Academy of Sciences of the United States of America2011
The human visual system's assumption that light comes from above is weak.
Article in Proceedings of the National Academy of Sciences of the United States of America, 2011. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 24 papers.
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Who cites it
24 citing papers in PubMed.
- Gaze perception under vertical asymmetries in illumination.Scientific reports · 2026Article
- A Kinetic Ecological Approach to Beauty Perception: A Perspective Review on the Case of Symmetry and the Golden Ratio.The European journal of neuroscience · 2025Review
- Faces in shadows: silhouette light, underlight and toplight elicit increased early posterior negativity.Frontiers in neuroscience · 2025Article
- High-level aftereffects reveal the role of statistical features in visual shape encoding.Current biology : CB · 2024Article
- Detection of Mooney faces is robust to image asymmetries produced by illumination.Journal of vision · 2023Article
- Color and gloss constancy under diverse lighting environments.Journal of vision · 2023Article
- A dolphin-inspired compact sonar for underwater acoustic imaging.Communications engineering · 2022Article
- From boundaries to bumps: When closed (extremal) contours are critical.Journal of vision · 2021Article
- Scaling depth from shadow offset.Journal of vision · 2021Article
- Distinct processes of lighting priors for lightness and 3-D shape perception.Journal of vision · 2021Article
- Hyperspectral environmental illumination maps: characterizing directional spectral variation in natural environments.Optics express · 2019Article
- Illumination discrimination in the absence of a fixed surface-reflectance layout.Journal of vision · 2018Article
- Article
- The light-from-above prior is intact in autistic children.Journal of experimental child psychology · 2017Article
- Reference Frames and 3-D Shape Perception of Pictured Objects: On Verticality and Viewpoint-From-Above.i-Perception · 2016Article
- Perception and Reality: Why a Wholly Empirical Paradigm is Needed to Understand Vision.Frontiers in systems neuroscience · 2015Article
- Human vision is attuned to the diffuseness of natural light.Journal of vision · 2014Article
- Article
- Learning what to expect (in visual perception).Frontiers in human neuroscience · 2013Review
- A Bayesian model of lightness perception that incorporates spatial variation in the illumination.Journal of vision · 2013Article
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3 authors.
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Abstract
Every biological or artificial visual system faces the problem that images are highly ambiguous, in the sense that every image depicts an infinite number of possible 3D arrangements of shapes, surface colors, and light sources. When estimating 3D shape from shading, the human visual system partly resolves this ambiguity by relying on the light-from-above prior, an assumption that light comes from overhead. However, light comes from overhead only on average, and most images contain visual information that contradicts the light-from-above prior, such as shadows indicating oblique lighting. How does the human visual system perceive 3D shape when there are contradictions between what it assumes and what it sees? Here we show that the visual system combines the light-from-above prior with visual lighting cues using an efficient statistical strategy that assigns a weight to the prior and to the cues and finds a maximum-likelihood lighting direction estimate that is a compromise between the two. The prior receives surprisingly little weight and can be overridden by lighting cues that are barely perceptible. Thus, the light-from-above prior plays a much more limited role in shape perception than previously thought, and instead human vision relies heavily on lighting cues to recover 3D shape. These findings also support the notion that the visual system efficiently integrates priors with cues to solve the difficult problem of recovering 3D shape from 2D images.
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