We reported a case of selective alexia for Kana and selective agraphia for Kanji due to left temporo-parietal subcortical hematoma. The subject was a 74-year-old right-handed man who exhibited difficulty in Kana reading and Kanji writing. His abilities at kanji reading and Kana writing were well preserved. Kinesthetic facilitation was effective in Kana reading. Characteristics of Kana alexia were similar to pure alexia. The subject was able to copy both Kana and Kanji letters. On admission he showed disability in word finding and auditory comprehension, but one month later these aphasic symptoms improved.
    The Japanese language is seen to have four individual neural pathways for reading and writing : for Kana reading, Kanji reading, kana writing and Kanji writing. Difficulty in Kana reading can be caused by disconnection of the pathway between the occipital cortex, which is respo nsible for the visual image of Kana letters, and Wernicke's area by way of the angular gyrus. Difficulty in Kanji writing can be caused by disconnection of the pathway from Wernicke's area to part of the motor area via the occipital lobe. In the present case the two pathways of Kana reading and Kanji writing were selectively impaired, and a CT scan disclosed a subcortical hematoma in the left temporo-parietal junctional area. These findings support our speculation that the two neural pathways of Kana reading and Kanji writing can be selectively disconnected by a left temporo-parietal subcortical lesion.

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