The anatomic basis of pure alexia.

The behavioral and anatomic correlates of pure alexia were analyzed in 16 patients. Right homonymous hemianopia failed to appear in three patients, who had right achromatopsia instead. Color anomia and unilateral optic ataxia were seen in six patients. Memory defects were found in two patients. Visual agnosia was noted in two. No patient had visual disorientation. The crucial anatomic correlate of alexia was a lesion of the paraventricular white matter of the left occipital lobe, capable of compromising both interhemispheric and intrahemispheric visual pathways. The lesion associated with color anomia was in the mesial occipitotemporal junction of the left hemisphere.