Selective Kana agraphia: a case report.

We present a Japanese man with selective Kana (phonogram) agraphia as a sequela of two cerebral infarctions in a part of the left angular gyrus and its adjoining posterior superior temporal gyrus and the left corona radiata. The agraphia of this patient showed the following features: (1) His writing difficulty was greater for Kana than for Kanji (ideogram) when a word was polysyllabic. (2) Kana errors consisted of perseveration and substitution with another letter, resulting in jargon agraphia. (3) This jargon agraphia often contained a correct number of letters for a target word. Based on these findings, we speculate that the basic defect of this agraphia lies in the process of converting an acoustic word image into a Kana motor grapheme sequence.