Influence of cognitive abilities on literacy skills in a Korean-Japanese bilingual child with developmental dyslexia.

Some individuals with developmental dyslexia show dissociation in reading skills between languages. The occurrence of dissociation depends on differences in the orthographic characteristics and cognitive demands of languages. This article reports on a Korean-Japanese bilingual and biliterate boy, SJ, with developmental dyslexia (aged 11 years), who displayed dissociation between Korean and Japanese in reading and writing accuracy. This study aimed to discuss possible accounts for the profile of his literacy skills from orthographic and cognitive perspectives. To accomplish this aim, we measured SJ's literacy skills, receptive vocabulary, and cognitive abilities (i.e., phonological skills, naming speed, and visual skills) in both Korean and Japanese. Then, we compared his skills to those of monolingual and bilingual children. In terms of accuracy, his reading skills in Korean did not differ significantly from those of bilinguals, although they were lower than Korean monolinguals. His spelling skills were within the average range for Korean monolinguals and bilinguals. In contrast, his reading and writing accuracy levels in Japanese were low compared to both Japanese monolinguals and bilinguals. Moreover, his reading and writing deficits were more remarkable in Japanese kanji. However, his cognitive profile was similar between languages. Specifically, he showed deficits in phonological skills and naming speed in both languages, as well as deficits in visual skills. These results were explained by the facts that visual skills are one of the significant predictors of reading and writing accuracy in Japanese but not in Korean, and that visual skills are a key in learning kanji. Thus, our case, SJ, supports the cognitive account, namely, the idea that different cognitive demands on the development of literacy skills can cause dissociation in literacy skills (especially in terms of accuracy) in bilingual children.

The Influence of Orthographic Units Across Korean Children of Different Ages in Hangul Reading.

Using the dual-route reading model as a framework, this study investigated the following research questions on Hangul reading: Which orthographic units (e.g., letters, syllable blocks, and words) influence the reading performance of Korean-speaking children? In addition, do the influential units change as the children grow up? To answer these questions, we tested the effects of age, frequency, lexicality, and two types of length-the numbers of letters (letter length) and syllable blocks (syllable block length)-and the interactions of these factors in the reading performance of Korean-speaking preschool and primary school children from first to third grade. Regarding reading latencies, there was a significant three-way interaction of age × lexicality × length regardless of the type of length. This interaction indicated that, for words only, the interaction between age and length was significant. Accordingly, the length effect decreased as children's age increased. When reading latencies for words were analyzed with a mixed-effect model consisting of three factors-age, frequency, and length-neither a main effect of syllable block length nor an interaction of syllable block length with age was significant. In contrast, the interaction of age × letter length in word reading latencies remained significant. The length effect was smaller as children's age increased. In addition, the frequency effect was significant and interacted significantly with age. The frequency effect increased as children's age increased. In conclusion, significant frequency effects indicate that Korean-speaking children use the lexical process in addition to the non-lexical process when reading Hangul words. Importantly, as children grow up, a larger orthographic unit, that is, words, is more strongly related to reading performance, whereas the influence of the smaller orthographic unit, that is, letters, decreases.

A case of acquired phonological dyslexia with selective impairment of Kanji: analysis of reading impairment mechanism using cognitive neuropsychological models for reading.

We report a Japanese-speaking patient who showed acquired phonological dyslexia only in Kanji; difficulty in reading two-character Kanji nonwords despite her ability to read Kana nonwords, Kana words, and two-character Kanji inconsistent-atypical words; and inability to repeat reversal nonwords. We investigated the mechanism of nonword reading impairment using the dual-route cascaded model, it was likely that the reading deficit of Kanji nonwords with multiple pronunciations resulted from the dysfunction of the character-to-sound conversion rule system. The patient's reading performance on the dissociation of Kana and Kanji was considered to reflect the difference in the consistency of orthography-to-phonology mapping.

The effect of the position of atypical character-to-sound correspondences on reading kanji words aloud: Evidence for a sublexical serially operating kanji reading process.

In English, the size of the regularity effect on word reading-aloud latency decreases across position of irregularity. This has been explained by a sublexical serially operating reading mechanism. It is unclear whether sublexical serial processing occurs in reading two-character kanji words aloud. To investigate this issue, we studied how the position of atypical character-to-sound correspondences influenced reading performance. When participants read inconsistent-atypical words aloud mixed randomly with nonwords, reading latencies of words with an inconsistent-atypical correspondence in the initial position were significantly longer than words with an inconsistent-atypical correspondence in the second position. The significant difference of reading latencies for inconsistent-atypical words disappeared when inconsistent-atypical words were presented without nonwords. Moreover, reading latencies for words with an inconsistent-atypical correspondence in the first position were shorter than for words with a typical correspondence in the first position. This typicality effect was absent when the atypicality was in the second position. These position-of-atypicality effects suggest that sublexical processing of kanji occurs serially and that the phonology of two-character kanji words is generated from both a lexical parallel process and a sublexical serial process.

A patient with aphasia using the nonsemantic lexical route for Kanji reading.

We report a patient with aphasia, caused by cerebral hemorrhage, who probably used the nonsemantic lexical route when reading words aloud. To investigate the mechanisms underlying her reading dysfunction, we analyzed her reading abilities using the Dual-Route Cascaded Model. Language tests resulted in low correct percentages for both reading comprehension and reading nonwords aloud, suggesting problems in the semantic system and the nonlexical route. Conversely, the patient showed high scores on the reading words aloud task. Although she failed to understand many inconsistent-atypical words in the reading comprehension test, she correctly read most words aloud, suggesting that she used the nonsemantic lexical route. In addition, the lexical reading route was analyzed in detail by using inconsistent-atypical Kanji words as stimuli. Finally, we analyzed her reading dysfunction compared with previous cases.

An investigation into kana reading development in normal and dyslexic Japanese children using length and lexicality effects.

This is the first study to report differences between Japanese children with and without dyslexia in the way string-length and lexicality effects are manifested when reading Japanese kana. These children were asked to read kana words and non-words consisting of either two or five kana characters. The results showed that the error rates of the normal Preschoolers and Primary-School children with dyslexia were higher than those of the normal Primary-School children. Further, the reading latencies of the normal Preschoolers, First-graders and dyslexics were significantly longer than those of the normal Second, Third and Fifth/Sixth graders. Moreover, reading latencies became shorter as the age of the participants increased. Both normal and dyslexic children showed significant effects of length and lexicality on reading latencies. However, the interaction between the length and lexicality was only seen in normal children from the Second-grade onwards. These results suggest that (1) normal First-graders reach a ceiling in terms of reading accuracy and that (2) as Japanese normal children become older, they become better at lexical reading processes, which leads to fluent kana reading, but that (3) the dyslexics, even at Fifth/Sixth grades, have not developed sufficient lexical reading processes.