Risk For Dyslexia Research Articles

CFD-14: detecting literacy and dyslexia risks in early and primary education

This study validates the CFD-14 questionnaire, designed for families to detect early risk of literacy difficulties and dyslexia in compulsory schooling. The sample included families of 1385 students from preschool (5 years old) and 1st to 6th grade of primary education, with a median age of 9 years and two months. The CFD-14 comprises 14 items reflecting common dyslexia indicators. Its one-dimensional factorial structure was confirmed, demonstrating reliability and criterion validity through five evidences: correlation of questionnaire scores with teacher and family assessments, comparison of CFD-14 scores between a dyslexic group (n = 13) and the general sample, analysis between families with and without a history of difficulties, and comparison between groups with persistent spelling errors and those without. A direct score at the 90th percentile was identified as the objective criterion to pinpoint students at risk of literacy difficulties.

An abbreviated Chinese dyslexia screening behavior checklist for primary school students using a machine learning approach.

To increase early identification and intervention of dyslexia, a prescreening instrument is critical to identifying children at risk. The present work sought to shorten and validate the 30-item Mandarin Dyslexia Screening Behavior Checklist for Primary School Students (the full checklist; Fan et al., , 19, 521-527, 2021). Our participants were 15,522 Mandarin-Chinese-speaking students and their parents, sampled from classrooms in grades 2-6 across regions in mainland China. A machine learning approach (lasso regression) was applied to shorten the full checklist (Fan et al., , 19, 521-527, 2021), constructing grade-specific brief checklists first, followed by a compilation of the common brief checklist based on the similarity across grade-specific checklists. All checklists (the full, grade-specific brief, and common brief versions) were validated and compared with data in our sample and an external sample (N = 114; Fan et al., , 19, 521-527, 2021). The results indicated that the six-item common brief checklist showed consistently high reliability (αs > .82) and reasonable classification performance (about 60% prediction accuracy and 70% sensitivity), comparable to that of the full checklist and all grade-specific brief checklists across our current sample and the external sample from Fan et al., , 19, 521-527, (2021). Our analysis showed that 2.42 (out of 5) was the cutoff score that helped classify children's reading status (children who scored higher than 2.42 might be considered at risk for dyslexia). Our final product is a valid, accessible, common brief checklist for prescreening primary school children at risk for Chinese dyslexia, which can be used across grades and regions in mainland China.

Association Between Exposure to Heavy Metals and Dyslexic Risk Among Children: A Narrative Review

Context: Developmental dyslexia (DD) is a learning disorder characterized by difficulties in reading due to challenges in sound identification and letter-word association. This study aimed to evaluate the correlation between exposure to heavy metals (HMs) and the risk of dyslexia in children through a narrative review. Evidence Acquisition: The study adopted a narrative review approach, utilizing keywords to search reputable databases like Google Scholar, Scopus, PubMed, and Web of Science. Relevant research meeting specific criteria were selected for analysis. Results: In most studies, metals were measured in children's urine. The results indicated that children with DD had lower levels of essential metals such as zinc (Zn), selenium (Se), and cobalt (Co). In contrast, toxic metals like mercury (Hg), cadmium (Cd), silver (Ag), and lead (Pb) were significantly higher compared to the control group. Based on the results of previous studies, no significant variations were observed in other essential and toxic metals between the case and control groups. Conclusions: Essential metals like Zn, Se, and Co may protect against DD in children, whereas toxic metals such as Pb, Ag, Cd, and Hg could exacerbate the disorder. It is recommended to evaluate essential and toxic metal levels in parents before and during pregnancy and in infants to mitigate dyslexia risk in children.

Early maturation of neural auditory novelty detection − Typical development with no major effects of dyslexia risk or music intervention

ObjectiveTo determine the early development of novelty detection and the effect of familial dyslexia risk and infant music intervention on this development. MethodsIn the longitudinal DyslexiaBaby study, we investigated the maturation of novelty-P3 and late-discriminative negativity (LDN) event-related potentials to novel sounds at birth (N = 177) and at the ages of 6 (N = 83) and 28 months (N = 131). ResultsNovelty-P3 was elicited at all ages, whereas LDN was elicited at 6 and 28 months. Novelty-P3 amplitude was largest at 6 months, and its latency decreased with age. LDN amplitude decreased and latency increased between 6 to 28 months. Dyslexia risk or intervention had no effects, apart from a longer LDN latency in the high-risk than no-risk group. ConclusionsAlready neonates respond to novel environmental sounds, indicating prerequisites for detecting potentially relevant events at birth. Maturation influences neural novelty detection. SignificanceNovelty detection is crucial for perceiving important events, but its early development has been scarcely studied. We found, with a large sample, that neonates detect novel events, and showed the developmental pattern of its neural signature. The results serve as a reference for studies on typical and atypical novelty-detection development in infancy when behavioral testing is challenging.

The role of cumulative family risks in the relationship between executive functioning and school readiness

This study investigated the roles of cumulative family risks and executive functioning (EF) in explaining preschool children’s school readiness. The cumulative family risks comprised family socioeconomic status (SES), home literacy environment (HLE), and familial risk of dyslexia (FRD). The participants were 955 first-year kindergarten children (Mage = 3.53 years, SD=0.41, 46.60 % girls) and their parents (Mage = 35.56 years, SD=6.31, 82.7 % mothers) from Hong Kong, China. The parents completed a survey package measuring their children’s school readiness, EF skills, and the three above-mentioned cumulative family risks. Hierarchical regression analysis, controlling for children’s age and gender, was performed to test the unique contributions of EF and the profiles of cumulative family risks to school readiness. The results showed that in addition to the significant role of EF, HLE risk was significantly associated with school readiness. The association between EF and school readiness was significantly weaker in children with three or more family risks than in their peers. The findings highlight the necessity of developing family education and school–family–community collaboration programs to enhance the school readiness of children, especially those with multiple family risks.

Development and Validation of Phonological Processing Assessment Tool in Kannada Language

The research evidence in orthographically transparent language Kannada indicates that phonological processing significantly influences reading acquisition, and deficits increase the risk of dyslexia. A comprehensive assessment of phonological processing that includes phonological awareness, phonological memory, and phonological naming is crucial for implementing effective intervention strategies, thereby reducing the risk of dyslexia. However, there is a notable absence of phonological processing assessment tools specifically designed and validated for children learning to read alphasyllabary Kannada. The present study addresses this gap by developing and validating a phonological processing assessment tool for children between Grade I and Grade III learning to read alphasyllabary languages such as Kannada. The study was conducted in two distinct phases. The first phase consisted of developing and piloting a phonological processing assessment tool. It included the stages of task selection, item generation, content validation, pilot testing, and reliability analysis. In the second phase, the developed tool was validated by administering it to both typically developing children and children at-risk for dyslexia from Grade I through Grade III. Subsequently, the developmental appropriateness of the tool was tested by comparing the performance of typically developing children between the grades. Additionally, diagnostic validity, including sensitivity, specificity, and area under the curve, was established by comparing the performance of typically developing and at-risk children. The study makes a substantial contribution to research on reading in Akshara orthographies, offering a valuable clinical tool for identifying children at-risk for dyslexia.

Developmental dyslexia genes are selectively targeted by diverse environmental pollutants

BackgroundDevelopmental dyslexia, a complex neurodevelopmental disorder, not only affects children’s academic performance but is also associated with increased healthcare costs, lower employment rates, and reduced productivity. The pathogenesis of dyslexia remains unclear and it is generally considered to be caused by the overlap of genetic and environmental factors. Systematically exploring the close relationship between exposure to environmental compounds and susceptibility genes in the development of dyslexia is currently lacking but high necessary.MethodsIn this study, we systematically compiled 131 publicly reported susceptibility genes for dyslexia sourced from DisGeNET, OMIM, and GeneCards databases. Comparative Toxicogenomics Database database was used to explore the overlap between susceptibility genes and 95 environmental compounds, including metals, persistent organic pollutants, polycyclic aromatic hydrocarbons, and pesticides. Chemical bias towards the dyslexia risk genes was taken into account in the observation/expectation ratios > 1 and the corresponding P value obtained by hypergeometric probability test.ResultsOur study found that the number of dyslexia risk genes targeted by each chemical varied from 1 to 109. A total of 35 chemicals were involved in chemical reactions with dyslexia-associated genes, with significant enrichment values (observed/expected dyslexia risk genes) ranging from 1.147 (Atrazine) to 66.901 (Dibenzo(a, h)pyrene).ConclusionThe results indicated that dyslexia-associated genes were implicated in certain chemical reactions. However, these findings are exploratory, and further research involving animal or cellular experiments is needed.

Reading and emotional-behavioural development in Finnish children: a longitudinal study of associations

AbstractPoor reading has been linked to negative outcomes on a wide range of emotional-behavioural dimensions in children. However, little is known about the time course of these associations. In this study we analyse data from a sample of Finnish children (N = 199; 106 boys) which included measures of reading fluency in grade 1 (age 7 or 8), and emotional (anxiety, depression, and somatization) and behavioural (adaptability, aggression, attention, atypicality, hyperactivity, social skills, and withdrawal) development at ages 4, 5, 6 (pre-school) and 9 (school-aged). In a series of stepwise regression models that controlled for non-verbal IQ and family risk for dyslexia, we tested if pre-school emotional-behavioural measures were associated with school-aged reading fluency, and whether school-aged reading fluency was associated with later emotional-behavioural development. We also tested if these associations were moderated by reported gender. Consistent with previous longitudinal studies, we found that poorer attention before school was associated with poorer reading in the early school years which in turn was associated with higher levels of anxiety and inattention in children in middle school. None of these associations were moderated by gender.

DysDiTect: Dyslexia Identification Using CNN-Positional-LSTM-Attention Modeling with Chinese Dictation Task.

Handwriting difficulty is a defining feature of Chinese developmental dyslexia (DD) due to the complex structure and dense information contained within compound characters. Despite previous attempts to use deep neural network models to extract handwriting features, the temporal property of writing characters in sequential order during dictation tasks has been neglected. By combining transfer learning of convolutional neural network (CNN) and positional encoding with the temporal-sequential encoding of long short-term memory (LSTM) and attention mechanism, we trained and tested the model with handwriting images of 100,000 Chinese characters from 1064 children in Grades 2-6 (DD = 483; Typically Developing [TD] = 581). Using handwriting features only, the best model reached 83.2% accuracy, 79.2% sensitivity, 86.4% specificity, and 91.2% AUC. With grade information, the best model achieved 85.0% classification accuracy, 83.3% sensitivity, 86.4% specificity, and 89.7% AUC. These findings suggest the potential of utilizing machine learning technology to identify children at risk for dyslexia at an early age.

Do early musical impairments predict later reading difficulties? A longitudinal study of pre-readers with and without familial risk for dyslexia.

The present longitudinal study investigated the hypothesis that early musical skills (as measured by melodic and rhythmic perception and memory) predict later literacy development via a mediating effect of phonology. We examined 130 French-speaking children, 31 of whom with a familial risk for developmental dyslexia (DD). Their abilities in the three domains were assessed longitudinally with a comprehensive battery of behavioral tests in kindergarten, first grade, and second grade. Using a structural equation modeling approach, we examined potential longitudinal effects from music to literacy via phonology. We then investigated how familial risk for DD may influence these relationships by testing whether atypical music processing is a risk factor for DD. Results showed that children with a familial risk for DD consistently underperformed children without familial risk in music, phonology, and literacy. A small effect of musical ability on literacy via phonology was observed, but may have been induced by differences in stability across domains over time. Furthermore, early musical skills did not add significant predictive power to later literacy difficulties beyond phonological skills and family risk status. These findings are consistent with the idea that certain key auditory skills are shared between music and speech processing, and between DD and congenital amusia. However, they do not support the notion that music perception and memory skills can serve as a reliable early marker of DD, nor as a valuable target for reading remediation. RESEARCH HIGHLIGHTS: Music, phonology, and literacy skills of 130 children, 31 of whom with a familial risk for dyslexia, were examined longitudinally. Children with a familial risk for dyslexia consistently underperformed children without familial risk in musical, phonological, and literacy skills. Structural equation models showed a small effect of musical ability in kindergarten on literacy in second grade, via phonology in first grade. However, early musical skills did not add significant predictive power to later literacy difficulties beyond phonological skills and family risk status.

Cognitive Profiles in Preschool Children at Risk for Co-Occurring Dyslexia and ADHD

Developmental dyslexia and attention-deficit/hyperactivity disorder (ADHD) co-occur in 15–40% of individuals diagnosed with one disorder. Despite substantial research on the cognitive profiles of preschoolers at risk for either dyslexia or ADHD, studies have neglected children at risk for co-occurring dyslexia and ADHD. Thus, our study compared the cognitive profile of preschoolers at risk for dyslexia with the profile of children at risk for co-occurring dyslexia and ADHD. We assessed 50 preschoolers at dyslexia risk (DR), 50 at dyslexia + ADHD risk (DAR), and 48 without risk (NR) (Mage = 67 months). Our assessment encompassed phonological processing, executive functioning (EF), receptive vocabulary, and processing speed. Principal component analysis revealed two distinct components within the measures of EF, a verbal short-term memory and an EF component. ANOVA revealed that the NR group outperformed risk groups across measures, except for cognitive flexibility and delay of gratification. Notably, the DR and DAR groups did not differ in most measures but showed near-significant differences on the EF component, with the DR group having higher composite scores than the DAR group. In conclusion, ADHD risk did not impact the cognitive performance of children at risk for dyslexia but might amplify EF problems that at-risk preschoolers encounter.

Developmental dyslexia susceptibility genes DNAAF4, DCDC2, and NRSN1 are associated with brain function in fluently reading adolescents and young adults.

Reading skills and developmental dyslexia, characterized by difficulties in developing reading skills, have been associated with brain anomalies within the language network. Genetic factors contribute to developmental dyslexia risk, but the mechanisms by which these genes influence reading skills remain unclear. In this preregistered study (https://osf.io/7sehx), we explored if developmental dyslexia susceptibility genes DNAAF4, DCDC2, NRSN1, and KIAA0319 are associated with brain function in fluently reading adolescents and young adults. Functional MRI and task performance data were collected during tasks involving written and spoken sentence processing, and DNA sequence variants of developmental dyslexia susceptibility genes previously associated with brain structure anomalies were genotyped. The results revealed that variation in DNAAF4, DCDC2, and NRSN1 is associated with brain activity in key language regions: the left inferior frontal gyrus, middle temporal gyrus, and intraparietal sulcus. Furthermore, NRSN1 was associated with task performance, but KIAA0319 did not yield any significant associations. Our findings suggest that individuals with a genetic predisposition to developmental dyslexia may partly employ compensatory neural and behavioral mechanisms to maintain typical task performance. Our study highlights the relevance of these developmental dyslexia susceptibility genes in language-related brain function, even in individuals without developmental dyslexia, providing valuable insights into the genetic factors influencing language processing.

Association of exposure to phthalates and phthalate alternatives with dyslexia in Chinese primary school children.

Previous studies have shown associations between children's exposure to phthalates and neurodevelopmental disorders. Whereas the impact of exposure to phthalate alternatives is understudied. This study aimed to evaluate the association of exposure to phthalates/their alternatives with the risk of dyslexia. We recruited 745 children (355 dyslexia and 390 non-dyslexia) via the Tongji Reading Environment and Dyslexia Research Project, and their urine samples were collected. A total of 26 metabolites of phthalates/their alternatives were measured. Multivariate logistic regression and quantile-based g-computation were used to estimate the associations of exposure to the phthalates/their alternatives with dyslexia. More than 80% of the children had 17 related metabolites detected in their urine samples. After adjustment, the association between mono-2-(propyl-6-hydroxy-heptyl) phthalate (OH-MPHP) with the risk of dyslexia was observed. Compared with the lowest quartile of OH-MPHP levels, the odds of dyslexia for the third quartile was 1.93 (95% CI 1.06, 3.57). Regarding mixture analyses, it was found that OH-MPHP contributed the most to the association. Further analyses stratified by sex revealed that this association was only observed in boys. Our results suggested a significantly adverse association of di-2-propylheptyl phthalate exposure with children's language abilities. It highlights the necessity to prioritize the protection of children's neurodevelopment by minimizing their exposure to endocrine-disrupting chemicals like di-2-propylheptyl phthalate.

Action video games normalise the phonemic awareness in pre-readers at risk for developmental dyslexia

Action video-games (AVGs) could improve reading efficiency, enhancing not only visual attention but also phonological processing. Here we tested the AVG effects upon three consolidated language-based predictors of reading development in a sample of 79 pre-readers at-risk and 41 non-at-risk for developmental dyslexia. At-risk children were impaired in either phonemic awareness (i.e., phoneme discrimination task), phonological working memory (i.e., pseudoword repetition task) or rapid automatized naming (i.e., RAN of colours task). At-risk children were assigned to different groups by using an unequal allocation randomization: (1) AVG (n = 43), (2) Serious Non-Action Video Game (n = 11), (3) treatment-as-usual (i.e., speech therapy, n = 11), and (4) waiting list (n = 14). Pre- and post-training comparisons show that only phonemic awareness has a significantly higher improvement in the AVG group compared to the waiting list, the non-AVG, and the treatment-as-usual groups, as well as the combined active groups (n = 22). This cross-modal plastic change: (i) leads to a recovery in phonemic awareness when compared to the not-at-risk pre-readers; (ii) is present in more than 80% of AVG at-risk pre-readers, and; (iii) is maintained at a 6-months follow-up. The present findings indicate that this specific multisensory attentional training positively affects how phonemic awareness develops in pre-readers at risk for developmental dyslexia, paving the way for innovative prevention programs.

Infant mismatch responses to speech-sound changes predict language development in preschoolers at risk for dyslexia

ObjectiveWe investigated how infant mismatch responses (MMRs), which have the potential for providing information on auditory discrimination abilities, could predict subsequent development of pre-reading skills and the risk for familial dyslexia. MethodsWe recorded MMRs to vowel, duration, and frequency deviants in pseudo-words at birth and 28 months in a sample over-represented by infants with dyslexia risk. We examined MMRs’ associations with pre-reading skills at 28 months and 4–5 years and compared the results in subgroups with vs. without dyslexia risk. ResultsLarger positive MMR (P-MMR) at birth was found to be associated with better serial naming. In addition, increased mismatch negativity (MMN) and late discriminative negativity (LDN), and decreased P-MMR at 28 months overall, were shown to be related to better pre-reading skills. The associations were influenced by dyslexia risk, which was also linked to poor pre-reading skills. ConclusionsInfant MMRs, providing information about the maturity of the auditory system, are associated with the development of pre-reading skills. Speech-processing deficits may contribute to deficits in language acquisition observed in dyslexia. SignificanceInfant MMRs could work as predictive markers of atypical linguistic development during early childhood. Results may help in planning preventive and rehabilitation interventions in children at risk of learning impairments.

Developing and validating an abbreviated adult reading history questionnaire in the Finnish and Dutch contexts

BackgroundThe adult reading history questionnaire (ARHQ) is frequently used in research on adult dyslexia and family risk for dyslexia. However, this measure is lengthy (23 items), reducing its applicability in studies with extensive assessment batteries.MethodsWe identified the best‐performing ARHQ items in a sample of 396 Finnish adults using exploratory factor analysis and item response theory. Consequently, we validated the brief questionnaire in independent Finnish and Dutch samples by comparing its performance with that of the complete questionnaire. We also evaluated how the scores on the questionnaires related to the scores on direct adult reading assessments in the Finnish samples. Finally, we tested how predictive parental questionnaires were of children's skills in the Dutch and one of the Finnish samples.ResultsFive items were selected to construct the short version of ARHQ. All of them relate to childhood/adolescent reading difficulties rather than current adult skills. The scores of the complete ARHQ significantly correlated with those of the abbreviated version in all samples. Moreover, in one of the samples, direct reading assessment scores had a stronger correlation with the short ARHQ than with the full version. Additionally, across all three samples parental scores on the short ARHQ were at least as predictive of children's reading skills as the complete ARHQ.ConclusionsThe short ARHQ proved to be on a par with the complete version in its usefulness for identifying adults with dyslexia. Future research should investigate whether the five selected items can effectively serve as a brief screening measure for adults with dyslexia in languages other than Finnish and Dutch.

Response to intervention as an identification strategy of the risk for dyslexia.

To develop on intervention process to identify children at risk of dyslexia, based on the Response to Intervention model. Specifically, to identify the pattern of changes in post-intervention performance in tasks of phonological awareness, working memory, lexical access, reading and writing; and to analyze which cognitive functions had a significant effect on the discriminating students at risk of dyslexia. Sample of 30 participants with Reading and writing difficulties, aged 8-11, from public/private schools, students from 3rd to 5th grade. Participants were submitted to a battery of cognitive-linguistic tests, before and after 12 intervention sessions. To monitor their performance, five reading and writing lists of words and pseudowords were applied. We qualitatively and quantitatively analyzed the differences in pre- and post-intervention performance of each participant; and among participants in the post-assessment, to understand the patterns of dyslexia vs non-dyslexia groups. There were statistically significant changes in: rapid automatized naming, narrative text comprehension, phonological awareness, rate and typology of hits/misses in reading and writing, and reading speed. Being the last three variables the most sensitive to discriminate the two groups, all with less post-intervention gains for the dyslexia group. The intervention focused on the stimulation of phonological skills and explicit and systematic teaching of graphophonemic correspondences contributed positively to the evolution of the group's participants. The intervention response approach favored the identification of children with a profile at risk for dyslexia, as distinct from children with other learning difficulties.

Resposta à intervenção como estratégia de identificação do risco para dislexia

ABSTRACT Purpose To develop on intervention process to identify children at risk of dyslexia, based on the Response to Intervention model. Specifically, to identify the pattern of changes in post-intervention performance in tasks of phonological awareness, working memory, lexical access, reading and writing; and to analyze which cognitive functions had a significant effect on the discriminating students at risk of dyslexia. Method Sample of 30 participants with Reading and writing difficulties, aged 8-11, from public/private schools, students from 3rd to 5th grade. Participants were submitted to a battery of cognitive-linguistic tests, before and after 12 intervention sessions. To monitor their performance, five reading and writing lists of words and pseudowords were applied. We qualitatively and quantitatively analyzed the differences in pre- and post-intervention performance of each participant; and among participants in the post-assessment, to understand the patterns of dyslexia vs non-dyslexia groups. Results There were statistically significant changes in: rapid automatized naming, narrative text comprehension, phonological awareness, rate and typology of hits/misses in reading and writing, and reading speed. Being the last three variables the most sensitive to discriminate the two groups, all with less post-intervention gains for the dyslexia group. Conclusions The intervention focused on the stimulation of phonological skills and explicit and systematic teaching of graphophonemic correspondences contributed positively to the evolution of the group's participants. The intervention response approach favored the identification of children with a profile at risk for dyslexia, as distinct from children with other learning difficulties.

Efficient Deep Learning Model for Detecting Dyslexia in Children from an Online Gamified Test Dataset

Dyslexia, a neurodevelopmental disorder, significantly impacts the learning ability of young children, often going undetected until later stages of education. Early detection of this disease is essential so that the impact can be significantly reduced by prompt intervention. But because of the reliance on labour-intensive procedures and limited scalability, traditional detection methods have not been able to provide immediate and accurate assessments. In response, this research introduces a standardised approach utilising an online gamified test dataset to predict the risk of dyslexia through an artificial neural network model, while incorporating advanced preprocessing techniques, effectively addressing the problems of class imbalance, outliers, and noise within the data. With an accuracy of 97%, this research demonstrates the remarkable utility of this approach and surpasses the results of the state-of-the-art methods. These findings, together with our model’s improved sensitivity and specificity, highlight the revolutionary potential of our approach. This innovation is important for the field of learning disorders and neurodevelopmental research because it has the potential to improve the educational paths of many children.

Cortical Structure in Pre-Readers at Cognitive Risk for Dyslexia: Baseline Differences and Response to Intervention.

Early childhood is a critical period for structural brain development as well as an important window for the identification and remediation of reading difficulties. Recent research supports the implementation of interventions in at-risk populations as early as kindergarten or first grade, yet the neurocognitive mechanisms following such interventions remain understudied. To address this, we investigated cortical structure by means of anatomical MRI before and after a 12-week tablet-based intervention in: (1) at-risk children receiving phonics-based training (n = 29; n = 16 complete pre-post datasets), (2) at-risk children engaging with AC training (n = 24; n = 15 complete pre-post datasets) and (3) typically developing children (n = 25; n = 14 complete pre-post datasets) receiving no intervention. At baseline, we found higher surface area of the right supramarginal gyrus in at-risk children compared to typically developing peers, extending previous evidence that early anatomical differences exist in children who may later develop dyslexia. Our longitudinal analysis revealed significant post-intervention thickening of the left supramarginal gyrus, present exclusively in the intervention group but not the active control or typical control groups. Altogether, this study contributes new knowledge to our understanding of the brain morphology associated with cognitive risk for dyslexia and response to early intervention, which in turn raises new questions on how early anatomy and plasticity may shape the trajectories of long-term literacy development.