Agnosia for familiar faces and odors in a patient with right temporal lobe dysfunction.

The authors studied a 53-year-old man with progressive prosopagnosia and inability to recognize his favorite foods by smell. He could not identify pictures of familiar faces, but he could match unfamiliar faces and distinguish them from familiar ones. He could not identify familiar odors, but he could detect them and could perceive them as pleasant or familiar. Neuroimaging revealed temporal lobe changes, especially on the right. Right temporal lesions may produce face and odor agnosia by preventing perceptual familiarity units from accessing semantic associations.