Abstract
We have investigated the characteristic deficits in two cases of pure agraphia due to left parietal infarction. The patients were both right-handed males, 66 and 50 years of age, respectively. Study was made of the number of correct responses using the same words (for kanji) and the same letters (for kana) in repeated tests over 18 months. Analysis of the nature of the errors made in the writing of kanji and kana showed that: (1) there were deficits in the writing of both kanji and kana, both of which improved similarly over time. (2) The errors in response to kanji were often the production of non-existent kanji which were similar to actual kanji, whereas the errors in response to kana were often transpositions of the correct kana. Analysis of the errors showed that most responses to both kanji and kana were orthographically similar to the correct answer. These findings in two cases of pure agraphia due to parietal lesions suggest that, in addition to auditoryvisual disconnexion and auditory-somesthetic disconnexion, there are also deficits in the production of the appropriate writing movements from somesthetic images, that is, somesthetic-somatomotor disconnexion.
