Walsh & Hoyt: Symptoms, Anatomy and Pathology

Cerebral achromatopsia. Deficits in color perception after cerebral lesions have been described for over a hundred years. Achromatopsic patients are always symptomatic, complaining that the world appears in shades of gray, like a black-and-white movie. Some also feel that the world appears less bright or has a ""dirty gray"" tinge. Less frequently, patients note abnormal color to their vision. Some find the world tinged with a hue, as if peering through a colored filter. Others see illusions of the residual colors perceived spreading beyond the boundaries of the objects from which they emanate, a type of visual perseveration. These positive color phenomena may occur transiently as the syndrome evolves after the acute lesion. For achromatopsic patients, daily activities that use color discrimination are impaired, such as distinguishing coins, stamps, or traffic lights; a good account of the experience of an achromatopsic artist exists