Cerebral achromatopsia is a medical disorder characterized by the inability to perceive color and to achieve satisfactory visual acuity in high light levels. Congenital achromatopsia is characterized the same way, however it is genetic, while Cerebral Achromatopsia occurs as a result of damage to certain parts of the brain. One part of the brain that is particularly integral to color discrimination is the inferior temporal gyrus. A 1995 study conducted by Heywood et al. was meant to highlight the parts of the brain that are important in achromatopsia in monkeys, however, it obviously sheds light on the areas of the brain related to achromatopsia in humans. In the study, one group of monkeys (group AT) received lesions in the temporal lobe anterior to V4 and the other group (group MOT) received lesions to the occipito-temporal area that corresponds in cranial location to the lesion that produces cerebral achromatopsia in humans. The study concluded that group MOT had no impairment of their color vision while the subjects in group AT all had severe impairments to their color vision, consistent with humans diagnosed with cerebral achromatopsia. This study shows that temporal lobe areas anterior to V4, which includes the inferior temporal gyrus, play a large role in patients with Cerebral Achromatopsia.
