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Published on: January 29, 2020
Perceiving surface reflectance requires attention
Erin Goddard1,2, Kavita Paul Remician1,3
1School of Psychology, University of New South Wales, Sydney, Australia.
Journal of Vision
|July 23, 2026
Summary
Perceptual color constancy, distinguishing surface properties from lighting, requires attention. Separating surface reflectance from illuminant properties is slow and attention-based, unlike simple color value searches.
Area of Science:
- Visual perception
- Cognitive neuroscience
- Computational vision
Background:
- Color constancy is the brain's ability to perceive stable surface properties despite changing illumination.
- The computational mechanisms underlying color constancy remain largely unknown.
- Understanding how the brain separates surface reflectance from illuminant properties is crucial.
Purpose of the Study:
- To investigate whether attention is necessary for the perceptual separation of surface reflectance from illuminant/filter properties.
- To compare the attentional requirements for searching surface reflectance versus local tristimulus value.
Main Methods:
- Visual search tasks were employed to measure search times.
- Participants searched for targets defined by surface reflectance.
- Participants also searched for targets defined by local tristimulus value.
Main Results:
- Visual search for color defined by tristimulus value was fast and near-parallel.
- Visual search for surface reflectance was slow and suggested serial attentional deployment.
- These findings indicate a difference in attentional requirements for processing surface reflectance versus illuminant properties.
Conclusions:
- The perceptual separation of surface reflectance from illuminant/filter properties likely requires attention.
- This process may involve attention-based mechanisms similar to feature binding.
- This study provides insights into the neural sequence underlying color constancy.
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