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.
View Article and Find Full Text PDFUsing 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.
View Article and Find Full Text PDFSeveral studies have reported a strong association between semantic system impairment and LARC error production. However, our patient with a left temporal lobe contusion, including the fusiform gyrus, showed LARC errors even in two-Kanji compound words, the meanings of which the patient understood. Also, the poor results of lexical decision and picture naming suggested problems in orthographic and phonological retrieval.
View Article and Find Full Text PDFMany studies have confirmed a brain dysfunction in people with developmental dyslexia (DD) in certain brain regions, including the left superior temporal gyrus and the left fusiform gyrus. However, the neurobiological substrates in Japanese-speaking people with dyslexia are not fully understood, mostly due to the uniqueness of the orthographic systems. Since a substantial part of the written Japanese includes the logographic Kanji as well as the phonographic Kana systems, the reading disability might be caused not only by a dysfunction in the phonological system, but also by a dysfunction in the visual recognition system.
View Article and Find Full Text PDFEmotion words constitute a special class of verbal stimuli which can quickly activate the limbic system outside the left-hemisphere language network. Such fast response to emotion words may arise independently of the left occipitotemporal area involved in visual word-form analysis and rely on a distinct amygdala-dependent emotion circuit involved in fearful face processing. Using a hemifield priming paradigm with fMRI, we explored how the left and right amygdala systems interact with the reading network during emotion word processing.
View Article and Find Full Text PDFIn 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.
View Article and Find Full Text PDFWe 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.
View Article and Find Full Text PDFObjective: This study aimed to investigate the relationship between the change of language symptoms and the change of regional cerebral blood flow (rCBF) in the recovery process of two children with acquired aphasia caused by infarctions from Moyamoya disease with an onset age of 8years.
Methods: We compared the results for the Standard Language Test of Aphasia (SLTA) with rCBF changes in 7 language regions in the left hemisphere and their homologous regions in the right hemisphere at 4 time points from 3weeks for up to 5years after the onset of aphasia, while controlling for the effect of age.
Results: In both cases, strong correlations were seen within a hemisphere between adjacent regions or regions that are connected by neuronal fibers, and between some language regions in the left hemisphere and their homologous regions in the right hemisphere.
The purpose of this study was to investigate methods for evaluating objectively the removability of three commercially available home reliners (Cushion Correct, Tafugurippu Pink A and Liodent Pink). After immersing each of the reliners in distilled water at 37ºC for 24 h, we compared their removability using the peel test with a finger, which was evaluated based on a visual analogue scale and the percentage of the residual area. An experimental rake-up test was also undertaken to quantify removability, evaluated based on the total amount of work required to remove it.
View Article and Find Full Text PDFThe purpose of this study was to determine if differential reading and spelling mechanisms were involved in a Japanese patient with aphasia. In our case, the patient scored low on all of the administered reading tasks, suggesting that both the reading lexical and non-lexical routes were impaired. In contrast, his writing-to-dictation score for Kana nonwords was high, suggesting that the spelling non-lexical route was intact.
View Article and Find Full Text PDFIntroduction: We investigated the neural processing of reading Japanese Kanji characters, which involves unique hierarchical visual processing, including the recognition of visual components specific to Kanji, such as "radicals."
Methods: We performed functional MRI to measure brain activity in response to hierarchical visual stimuli containing (1) real Kanji characters (complete structure with semantic information), (2) pseudo Kanji characters (subcomponents without complete character structure), (3) artificial characters (character fragments), and (4) checkerboard (simple photic stimuli).
Results: As we expected, the peaks of the activation in response to different stimulus types were aligned within the left occipitotemporal visual region along the posterior-anterior axis in order of the structural complexity of the stimuli, from fragments (3) to complete characters (1).
The purpose of this cross-sectional study was to examine the cognitive abilities that predict reading and spelling performance in Korean children in Grades 1 to 4, depending on expertise and reading experience. As a result, visual cognition, phonological awareness, naming speed and receptive vocabulary significantly predicted reading accuracy in children in Grades 1 and 2, whereas visual cognition, phonological awareness and rapid naming speed did not predict reading accuracy in children in higher grades. For reading, fluency, phonological awareness, rapid naming speed and receptive vocabulary were crucial abilities in children in Grades 1 to 3, whereas phonological awareness was not a significant predictor in children in Grade 4.
View Article and Find Full Text PDFBackground: This study investigated first the main cognitive abilities; phonological processing, visual cognition, automatization and receptive vocabulary in predicting reading and spelling abilities in Arabic. Second, we compared good/poor readers and spellers to detect the characteristics of cognitive predictors which contribute to identifying reading and spelling difficulties in Arabic speaking children.
Methods: A sample of 116 Tunisian third-grade children was tested on their abilities to read and spell, phonological processing, visual cognition, automatization and receptive vocabulary.
In this study, we investigated the characteristics of cognitive abilities as predictors of Korean reading and spelling ability, and the characteristics of the cognition of reading difficulty in Korean. In 103 Korean third-grade children, we tested ability to read and spell, nonverbal intelligence, vocabulary size, phonological cognitive processing, visual cognitive processing, and naming speed. Our results indicated that receptive vocabulary, phoneme awareness, and naming speed served as factors for predicting reading test score; receptive vocabulary served as a factor for predicting spelling test score.
View Article and Find Full Text PDFWe investigated the usability and limitations of Rapid Automatized Naming (RAN) results in 6-year-old Japanese preschool children to estimate whether reading difficulties will be encountered after school entry. We administered a RAN task to 1,001 preschool children. Then after they had entered school, we performed follow-up surveys yearly to assess their reading performance when these children were in the first, second, third and fourth grades.
View Article and Find Full Text PDFThis 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.
View Article and Find Full Text PDFWe report here on an investigation into the possible factors which might have contributed to language impairment (LI) in EM, a 14-year-old Japanese-English bilingual girl. EM was born in the UK to Japanese parents with no other siblings, and used English to communicate with all other people except for her parents. A delay in her English language development was identified at primary school in the UK, which was attributed to her bilingualism.
View Article and Find Full Text PDFThe dichotic presentation of two sinusoids with a slight difference in frequency elicits subjective fluctuations called binaural beat (BB). BBs provide a classic example of binaural interaction considered to result from neural interaction in the central auditory pathway that receives input from both ears. To explore the cortical representation of the fluctuation of BB, we recorded magnetic fields evoked by slow BB of 4.
View Article and Find Full Text PDFA mismatch between auditory sensation and expectant imagery of syllables elicited a possible equivalent of mismatch negativity in a previous study. The purpose of this study was to verify whether auditory imagery from musical notation could also mediate such imagery-based mismatch negativity. Neuromagnetic recording was obtained from eight musicians, who were instructed to identify unpredictably occurring pitch mismatches between a random tone sequence and a visually presented musical score.
View Article and Find Full Text PDFDuring silent reading, visual information provided by letters is converted to auditory information in the mind. The purpose of this study was to identify the primary locus for auditory verbal imagery in the brain. Neuromagnetic recording was obtained from 10 right-handed study participants, who were instructed to identify infrequently occurring phonological mismatches between a random-ordered sequence of syllable sounds and a visually presented syllabogram sequence.
View Article and Find Full Text PDFTwo Japanese patients with pure alexia, SH and YH, who showed right homonymous hemianopia following a left occipital lobe lesion, demonstrated letter-by-letter (LBL) reading in pronouncing Japanese kana words and nonwords. In contrast to alphabetic letters, each Japanese kana character has an invariant and identical pronunciation whether it appears in isolation or as a component of any word and nonword string. It is important to investigate the eye movements as well as reading latency and duration in Japanese-speaking LBL readers.
View Article and Find Full Text PDFObjective: To demonstrate the influence of auditory cortex lesions on auditory middle-latency responses (AMLRs) and middle-latency auditory-evoked magnetic fields (MLAEFs) in humans.
Material And Methods: A total of 15 normal subjects, 9 patients with left auditory cortex lesions and 1 patient with a right auditory cortex lesion were studied. MLAEFs were recorded from each hemisphere of the brain in a magnetically shielded room using a 37-channel SQUID gradiometer.
We performed fMRI measurements in normal children to clarify which cortical areas are commonly involved in the mirror system (MS) and mentalizing, which areas are specific for mentalizing, and whether children have the same neural networks for MS and mentalizing as adults. Normal children had the same neural networks for the MS and mentalizing as adults. Common activations were found in the superior temporal sulcus and the fusiform gyri, whereas mentalizing specific activation was found in the medial prefrontal, temporal pole and the inferior parietal cortices.
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