Progressive aphasia and surface Alexia in Japanese

We report the reading performance of a patient, NK, with selective left-temporal atrophy and progressive aphasia. NK showed surface alexlc reading with the following pattern: flawless oral reading of kana words; a deficit in reading of two-character kanji words that was particularly severe for lower frequency words with an unpredictable correspondence between the component characters and their pronunciations; a predominance of kanji-word reading errors In which characters were assigned pronunciations appropriate to other words containing these characters. These features were predicted and are interpreted on the basis of (a) recent studies of patients with progressive aphasia in English, (b) recent analyses of surface alexia in terms of an interaction between word frequency and neighbourhood-based consistency of spelling-sound correspondences, and (c) characteristics of the Japanese kana and kanji writing systems.