Acquired achromatopsia; Color agnosia; Color blindness; Cortical color blindness
Short Description or Definition
Following damage to the ventral medial region of the occipital lobe, known as the “color center” of the brain (Bartels and Zeki 2000), patients lose the ability to perceive color and therefore experience the world as varying shades of gray. This disorder is termed cerebral achromatopsia. The loss of color vision in these patients cannot be explained by the photoreceptors typically damaged or absent in patients with other types of color blindness.
Cerebral achromatopsia results from bilateral damage to the V4/V4α region of the color center. If patients experience complete ablation of V4, they lose color vision in their entire visual field. However, if patients experience unilateral damage to V4, hemi-achromatopsia ensues, where patients only lose color vision in the contralateral half of their visual field. In less extreme cases, known as...
References and Readings
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