4 patients with prosopagnosia are described. They presented associated neuropsychological deficits (achromatopsia, topographical disorientation) and visual field defects. In 1 case, gross pathological examination revealed bilateral symmetrical infero-medial occipito-temporal infarcts. In 2 other cases, computer tomography (CT) demonstrated bilateral inferior temporo-occipital infarction. In 1 case CT showed only occipital infarctions in the occipital lobes. This brings to 16 the number of anatomically studied cases of prosopagnosia (8 by necropsy, 8 by CT). In contrast to clinical localization, which often indicates only a right cerebral lesion, all anatomically verified cases of prosopagnosia exhibit bilateral lesions in the posterior cerebral artery distribution.