The Neural Correlates of Semantic and Grammatical Encoding During Sentence Production in a Second Language: Evidence From an fMRI Study Using Structural Priming

Japanese English learners have difficulty speaking Double Object (DO; give B A) than Prepositional Object (PO; give A to B) structures which neural underpinning is unknown. In speaking, syntactic and phonological processing follow semantic encoding, conversion of non-verbal mental representation into a structure suitable for expression. To test whether DO difficulty lies in linguistic or prelinguistic process, we conducted functional magnetic resonance imaging. Thirty participants described cartoons using DO or PO, or simply named them. Greater reaction times and error rates indicated DO difficulty. DO compared with PO showed parieto-frontal activation including left inferior frontal gyrus, reflecting linguistic process. Psychological priming in PO produced immediately after DO and vice versa compared to after control, indicated shared process between PO and DO. Cross-structural neural repetition suppression was observed in occipito-parietal regions, overlapping the linguistic system in pre-SMA. Thus DO and PO share prelinguistic process, whereas linguistic process imposes overload in DO.

Magnetoencephalography resting-state correlates of executive and language components of verbal fluency

Verbal fluency (VF) is a heterogeneous cognitive function that requires executive as well as language abilities. The purpose of this study was to elucidate the specificity of the resting state MEG correlates of the executive and language components. To this end, we administered a VF test, another verbal test (Vocabulary), and another executive test (Trail Making Test), and we recorded 5-min eyes-open resting-state MEG data in 28 healthy participants. We used source-reconstructed spectral power estimates to compute correlation/anticorrelation MEG clusters with the performance at each test, as well as with the advantage in performance between tests, across individuals using cluster-level statistics in the standard frequency bands. By obtaining conjunction clusters between verbal fluency scores and factor loading obtained for verbal fluency and each of the two other tests, we showed a core of slow clusters (delta to beta) localized in the right hemisphere, in adjacent parts of the premotor, pre-central and post-central cortex in the mid-lateral regions related to executive monitoring. We also found slow parietal clusters bilaterally and a cluster in the gamma 2 and 3 bands in the left inferior frontal gyrus likely associated with phonological processing involved in verbal fluency.

Comparison of Electrophysiological Indices of Children With Attention Deficit Hyperactivity Disorder (ADHD) Comorbid With and Without Reading Disorder (ADHD & RD)

BackgroundAttention Deficit Hyperactivity Disorder (ADHD) is a neuropsychiatric disorder. Most children and adolescents with ADHD have at least some developmental or mental disorders identified from the early years of elementary school. The most common of these are educational and learning problems in these children, which are probably due to the attention deficits of these children. Therefore, it is expected that the cortical activity pattern of ADHD children is different from ADHD comorbid with learning disabilities, which we have examined in this study.MethodsThis study evaluated the pattern of cortical activity in children 6 to 12 years old with ADHD comorbid with and without the reading disorder (ADHD & RD) using 21-channel electroencephalography. Multivariate analysis of variance with repeated measures in a 2 * 3 * 7 design and T-test was used for statistical analysis.ResultsThe results show that in ADHD children, the activity of different bands increases compared to ADHD comorbid with RD children. In the ADHD group compared to the ADHD comorbid with RD group, the theta/beta ratio in all three regions, especially the anterior region, is higher than the theta/alpha activity in those areas, and this group has significantly higher activity in all three brain regions, especially the anterior region, compared to ADHD comorbid with RD patients.ConclusionsFunctional changes in the left parietal cortex, which is part of the frontoparietal attention network and involved in phonological processing, reading, and calculation, are evident in children with ADHD comorbid with and without the reading disorder (ADHD & RD). However, ADHD without reading disorder shows more activation of the frontoparietal network than ADHD comorbid with reading disorder, and therefore it can be said that ADHD without reading disorder exerts more cognitive control. Therefore, it is likely to be possible to prevent educational problems in these children by using neurofeedback or prescribing drugs that increase the activity of the areas involved in attention.

Specific Learning Disabilities and Psychosocial Difficulties in Children

Children with specific learning disorders (SLDs) exhibit academic difficulties disproportional to their intellectual capabilities. A significant percentage of school-aged children worldwide are diagnosed with specific learning disabilities, with dyslexia being the most common. In Greece, epidemiological data propose that 50% of children in special education schools are diagnosed with learning disabilities, and 80% with reading difficulties. Children with SLD exhibit both internalized, such as depressive and anxiety disorders, self-esteem issues, eating and sleep difficulties, and externalized problems, including difficulties in socializing, developing friendships, and delinquent behavior. Moreover, research has shown that children with learning disabilities have an average (or above average) intelligence, and their poor academic performance is due to their lack of effective learning strategies. Concerning cognitive deficiencies, research suggests that no specific deficit is to fault; however, common deficits in children with SLDs are phonological processing and working memory.

A Diffusion Tensor Imaging Study on the Phonology-related Pathways in Cantonese-mandarin Bilinguals.

Cantonese and Mandarin are logographic languages, and the phonology is the main difference between the two languages. It is unclear whether long-term experience of Cantonese-Mandarin bilingualism will shape different brain white matter structures of pathways related to phonological processing. 30 Cantonese-Mandarin bilinguals and 30 Mandarin monolinguals completed diffusion-weighted imaging (DWI) scans and phonological processing tasks. The tractography and TBSS were used to investigate the structural differences in the bilateral superior longitudinal fasciculus (SLF), inferior longitudinal fasciculus (ILF) and inferior fronto-occipital fasciculus (IFOF) between Cantonese-Mandarin bilinguals and Mandarin monolinguals. Post-hoc correlation analysis was conducted to investigate the relationship between the different structures with phonological processing skills. Compared to the Mandarin monolinguals, the Cantonese-Mandarin bilinguals had higher fractional anisotropy (FA) along the left ILF, higher mean diffusivity (MD) in the clusters along the temporoparietal segment of SLF (tSLF), as well as higher axial diffusivity (AD) in the right tSLF, IFOF, bilateral ILF. The mean AD of the different voxels in the right IFOF and the mean FA of the different voxels in the left ILF were positively correlated with the inverse efficiency score (IES) of the Cantonese auditory and Mandarin visual rhyming judgment tasks respectively within the bilingual group. Long-term experience of Cantonese-Mandarin bilinguals shape different brain white matter structures including right tSLF, IFOF, bilateral ILF. The bilinguals’ white matter showed higher diffusivity, especially in the axonal direction, than the monolinguals. These changes were related to bilinguals’ phonological processing.

Phonological Processing, Visuospatial Skills, and Pattern Understanding in Chinese Developmental Dyscalculia

A number of previous studies have identified cognitive deficits in developmental dyscalculia (DD). Yet, most of these studies were in alphabetic languages, whereas few of them examined Chinese DD. Here, we conducted a study aiming to determine the cognitive factors associated with DD in Chinese children. Five candidate cognitive factors of DD—phonological retrieval, phonological awareness, visual–spatial attention, spatial thinking, and pattern understanding—were studied in the present study. A total of 904 Chinese children aged between 8 and 11 years participated in this study. From the sample, 97 children were identified with DD through tests of arithmetic ability, and 93 age and IQ–matched typically developing children were selected as controls. Logistic regression analysis revealed that phonological retrieval, pattern understanding, visual–spatial attention, and phonological awareness significantly predicted DD, whereas spatial thinking failed to do so. Results of logistic relative weights analysis showed that all five factors explained statistically significant amounts of variance in arithmetic scores. Phonological retrieval had the most influence on DD, followed by pattern understanding, visual–spatial attention, phonological awareness, and spatial thinking. These findings have important clinical implications for diagnosis and intervention of Chinese DD.

Educational Insights into Dyslexia

Dyslexia is a specific learning disorder characterized by difficulties in reading, writing, and spelling due to compromised phonological processing skills. Treatment of dyslexia solely with medical support is far-fetched. However, it can be surmounted by the combination of special education interventions and supportive psychosocial care. Suitable approaches coupled with beneficial learning strategies enable dyslexic learners with consummate linguistic achievement. Although dyslexia research offers an increased understanding from a biological standpoint, the knowledge gap on the educational front is unfortunately persistent. To this end, this paper revisits the teaching-learning aspects of dyslexia. Teaching principles and approaches, strategies to support learning, and personalized educational plans are discussed in detail. Acknowledging the difficulty, familiarizing with the approaches, and attaining successful outcomes via essential practices emphasize the inclusiveness of dyslexic learners in the curriculum. We contend that the educational insights into dyslexia will provide informed teaching and learning solutions.

Common Misconceptions about the Phonological Deficit Theory of Dyslexia

In this discussion paper, I review a number of common misconceptions about the phonological deficit theory (PDH) of dyslexia. These include the common but mistaken idea that the PDH is simply about phonemic awareness (PA), and, consequently, is a circular “pseudo”-explanation or epiphenomenon of reading difficulties. I argue that PA is only the “tip of the phonological iceberg” and that “deeper” spoken-language phonological impairments among dyslexics appear well before the onset of reading and even at birth. Furthermore, not even reading-specific expressions of phonological deficits—PA or pseudoword naming, can be considered circular if we clearly distinguish between reading proper—real meaning-bearing words, or real text, and the mechanisms (subskills) of reading development (such as phonological recoding). I also explain why an understanding of what constitutes an efficient writing system explains why phonology is necessarily a major source of variability in reading ability and hence a core deficit (or at least one core deficit) among struggling readers whether dyslexic or non-dyslexic. I also address the misguided notion that the PDH has now fallen out of favor because most dyslexia researchers have (largely) ceased studying phonological processing. I emphasize that acceptance of the PDH does not imply repudiation of other non-phonological hypotheses because the PDH does not claim to account for all the variance in reading ability/disability. Finally, I ask where neurobiology enters the picture and suggest that researchers need to exercise more caution in drawing their conclusions.