title: Pure agraphia in Romaji after left inferior frontal gyrus infarction: A case of selective deficit in syllable-to-grapheme conversion in Japanese.
abstract: The Japanese writing system employs two distinct categories of characters: Kana and Kanji. The difference between Kana and Kanji writing corresponds roughly to that between phonological and lexical systems in Western languages. When typing, most Japanese use alphabetical characters based purely on phonological rules. In particular, the Romaji system is used, in which a syllable consists of a single vowel, a consonant-vowel compound (e.g., ka, ki), or a sequence of consonant-y(semivowel)-vowel (e.g., kya, kyu). We describe a right-handed Japanese patient who developed pure agraphia that affected Romaji writing but preserved Kana and Kanji writing and who had a lesion in the left pars opercularis of the inferior frontal gyrus that extended to the anterior precentral gyrus. The patient demonstrated literal paragraphia in spelling Romaji across modalities. Our findings suggested that the patient's agraphia in Romaji after a confined left frontal infarction was manifested by a selective impairment in syllable-to-grapheme conversion.
authors: Department of Behavioral Neurology and Cognitive Neuroscience, Tohoku University Graduate School of Medicine, Sendai, Japan. Electronic address: ogura-kaeko@umin.ac.jp.
authors: Kaeko
authors: K
authors: Ogura
authors: Toshikatsu
authors: T
authors: Fujii
authors: Kyoko
authors: K
authors: Suzuki
authors: Etsuro
authors: E
authors: Mori
mesh_terms: D000381:Agraphia / Q000209:etiology* / Q000473:pathology / Q000503:physiopathology; D044466:Asian People; D002544:Cerebral Infarction / Q000150:complications* / Q000473:pathology / Q000503:physiopathology; D005625:Frontal Lobe / Q000473:pathology / Q000503:physiopathology*; D006801:Humans; D007564:Japan; D007802:Language; D008875:Middle Aged; D014956:Writing
keywords: Japanese writing system; Left frontal lobe; Pure agraphia; Romaji; Sound-to-letter conversion