ArticleProceedings of the National Academy of Sciences of the United States of America1999
The neurological basis of conscious color perception in a blind patient.
Article in Proceedings of the National Academy of Sciences of the United States of America, 1999. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 18 papers.
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18 citing papers in PubMed, 102 citations in OpenAlex.
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- Neural basis of the interaction between alerting and executive control.Frontiers in psychology · 2025Article
- Color discrimination in fixed saturation level of patients with acute traumatic injury.Frontiers in neurology · 2024Article
- Dimensional bias and adaptive adjustments in inhibitory control of monkeys.Animal cognition · 2021Article
- Visual Functions of Primate Area V4.Annual review of vision science · 2020Review
- Effects of word-evoked object size on covert numerosity estimations.Frontiers in psychology · 2015Article
- Contributions of magno- and parvocellular channels to conscious and non-conscious vision.Philosophical transactions of the Royal Society of London. Series B, Biological sciences · 2014Article
- Prestimulus oscillatory power and connectivity patterns predispose conscious somatosensory perception.Proceedings of the National Academy of Sciences of the United States of America · 2014Article
- Roles of contour and surface processing in microgenesis of object perception and visual consciousness.Advances in cognitive psychology · 2011Article
- In praise of subjective truths.The Journal of physiology · 2009Article
- The common magnitude code underlying numerical and size processing for action but not for perception.Experimental brain research · 2009Article
- fMR-adaptation reveals separate processing regions for the perception of form and texture in the human ventral stream.Experimental brain research · 2009Article
- Metacontrast masking and the cortical representation of surface color: dynamical aspects of edge integration and contrast gain control.Advances in cognitive psychology · 2008Article
- Spatial and temporal properties of cone signals in alert macaque primary visual cortex.The Journal of neuroscience : the official journal of the Society for Neuroscience · 2006Article
- The Ferrier Lecture 1995 behind the seen: the functional specialization of the brain in space and time.Philosophical transactions of the Royal Society of London. Series B, Biological sciences · 2005Article
- Sensory, computational and cognitive components of human colour constancy.Philosophical transactions of the Royal Society of London. Series B, Biological sciences · 2005Review
- Visual command hallucinations in a patient with pure alexia.Journal of neurology, neurosurgery, and psychiatry · 2004Article
- How does the cortex construct color?Proceedings of the National Academy of Sciences of the United States of America · 1999Article
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4 authors at 2 institutions in 1 country.
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Abstract
We have studied patient PB, who, after an electric shock that led to vascular insufficiency, became virtually blind, although he retained a capacity to see colors consciously. For our psychophysical studies, we used a simplified version of the Land experiments [Land, E. (1974) Proc. R. Inst. G. B. 47, 23-58] to learn whether color constancy mechanisms are intact in him, which amounts to learning whether he can assign a constant color to a surface in spite of changes in the precise wavelength composition of the light reflected from that surface. We supplemented our psychophysical studies with imaging ones, using functional magnetic resonance, to learn something about the location of areas that are active in his brain when he perceives colors. The psychophysical results suggested that color constancy mechanisms are severely defective in PB and that his color vision is wavelength-based. The imaging results showed that, when he viewed and recognized colors, significant increases in activity were restricted mainly to V1-V2. We conclude that a partly defective color system operating on its own in a severely damaged brain is able to mediate a conscious experience of color in the virtually total absence of other visual abilities.
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