RESUMO
Optic ataxia is characterized by an impaired visual control of the direction of arm reaching to a visual target, accompanied by defective hand orientation and grip formation. In humans, optic ataxia is associated with lesions of the superior parietal lobule, which also affect visually guided saccades and other forms of eye-hand coordination. A 67-year-old woman presented with sudden, unilateral, direct optic ataxia in the right homonymous half field and saccadic abnormalities which consisted of prolonged latency, undershoot dysmetria, and decreased velocity. Brain MRI showed a left parieto-occipital watershed infarction. It is suggested that lesions of the superior parietal lobule and the adjacent parietal eye field are responsible for optic ataxia and saccadic abnormalities, respectively.