Achromatopsia, color vision, and cortex

Brain damage can result in several disorders in color processing, one of which, cerebral achromatopsia, refers to the complete loss of color vision. Cerebral achromatopsia has been interpreted as a loss of color constancy as a consequence of damage to the color center, revealed by neuroimaging. The color center has been identified, probably erroneously, with cortical area V4 of the monkey brain. Patients with cerebral achromatopsia nevertheless can retain the ability to extract other attributes from the visual scene on the basis of pure color variation, notably form and motion. The pattern and variability of color impairments reflect multiple areas that are implicated in chromatic processing in the primate brain.