Although the term prosopagnosia recently is considered to refer only to “agnosia for well-known faces ” , almost all prosopagnosics have impairment of discrimination and learning of unknown faces. Only five exceptional cases of prosopagnosia with nomal discrimination of unknown faces have been reported until now. We report the sixth case of prosopagnosia with intact discrimination of unfamiliar faces.
    A 73-year-old right-handed female complained of disability to identify visually the faces of well-known persons following a slight attack of apoplexy. Perimetry revealed left homonymous hemianopsy. Neither hemiparesis nor hemihypesthesia was detected. Language and praxis were quite intact. Besides prosopagnosia, no visual agnosia was observed. Auditory and tactile agnosias were not detected.
    The patient was not able to identify visually her family members before they talk to her. She could recognize none of 20 photographs of famous personalities, which we used in order to assess facial identification. She also complained of loss of imagery of well-known faces. On the other hand, the patient showed quite normal performance on the tasks concerning discrimination and learning of unknown faces.
    By means of CT scan, occlusion of the lateral branch of the right posterior cerebral artery was considered to cause such prosopagnosic symptoms, in stead of occlusion of the main trunk of this artery which may be the ordinary cause of prosopagnosia.

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     A 68-year-old calligrapher developed difficulties in reading and writing confined to kanji characters. He was neither aphasic nor demented. Neurological examination revealed slight impairment of short-term memory and mild sensory impairment on the left half of the body.
    A computed tomographic scan showed a hypodense area in the inferior medial aspect of the right temporal lobe. This lesion was also detected by magnetic resonance imaging.
    The subject was thought to be incompletely right-handed from the evidence that he occasionally uses his left limbs in various daily activities, such as eating with a spoon, combing his hair, kicking a ball, etc.
    As the patterns of his errors in reading and writing kanji characters were not uniform, it was difficult to explain the mechanism of this specific type of alexia and agraphia only as a disturbance of semantic function in reading and writing kanji characters.

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