Different interhemispheric transfer of kanji and kana writing evidenced by a case with left unilateral agraphia without apraxia.

Recent neuropsychological studies have revealed that the processing of kanji (the Japanese morphograms) and kana (the Japanese syllabograms) involves different intrahemispheric mechanisms. We describe a patient showing left unilateral agraphia without apraxia for kanji, but not for kana, who was diagnosed by magnetic resonance imaging as having a lesion of the posterior body of the corpus callosum. This patient indicates that different neural pathways are used for kanji and kana not only intrahemispherically, but also interhemispherically.