Discrimination of cone contrast changes as evidence for colour constancy in cerebral achromatopsia

  title={Discrimination of cone contrast changes as evidence for colour constancy in cerebral achromatopsia},
  author={Anya C. Hurlbert and D. I. Bramwell and Charles A. Heywood and Alan Cowey},
  journal={Experimental Brain Research},
Abstract One proposed mechanism for underpinning colour constancy is computation of the relative activity of cones within one class – cone ratios, or cone contrasts – between surfaces in a fixed scene undergoing a change in illuminant. Although there is evidence that cone ratios do determine colour appearance under many conditions, the site or sites of their computation is unknown. Here, we report that a cerebrally achromatopsic observer, MS, displayed evidence of colour constancy in asymmetric… 

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