Gender Differences in Reading Impairment and in the Identification of Impaired Readers: Results From a Large-Scale Study of At-Risk Readers

Learning difficulties often not documented in newly diagnosed focal epilepsy

OBJECTIVE

A previous investigation of people with newly diagnosed focal epilepsy participating in the Human Epilepsy Project 1 (HEP1) revealed an association between learning difficulties and structural brain differences, suggesting an underlying relationship prior to seizure onset. To investigate physicians' practices of documentation learning difficulties during clinical encounters, we conducted a review of initial epileptologist encounter notes from HEP1 participants who self-reported early life learning difficulties separately as part of study enrollment.

METHODS

HEP1 enrolled 67 North American participants between June 2012 and November 2017 who self-reported one or more difficulties with learning (i.e., having repeated grade, receiving learning support/remediation, and/or formal diagnosis of a learning disability) prior to epilepsy diagnosis as part of the study enrollment. The epileptologist's initial encounter note was then reviewed in detail for each of these participants. Documentation of learning issues and specific diagnoses of learning disabilities was compared to participant characteristics. Regression analysis was used to test for any independent associations between participant characteristics and physician documentation of learning difficulties.

RESULTS

There were significant independent relationships between age, sex, and physician documentation of learning difficulties. On average, participants ages 22 and younger were 12.12 times more likely to have their learning difficulties documented compared to those 23 years and older (95 % CI: 2.226 to 66.02, p = 0.004). Additionally, male participants had 7.2 times greater odds of having their learning difficulty documented compared to female participants (95 % CI: 1.538 to 33.717, p = 0.012). There were no significant independent associations between race, language, employment, or geographical region.

SIGNIFICANCE

These findings highlight disparities in physician documentation for people with newly diagnosed focal epilepsy and a history of learning difficulties. In the HEP1 cohort, physicians were more likely to document learning difficulties in males and in younger individuals. Systematic practice standards are important for reducing healthcare disparities across populations, improving clinical care to individuals, as well as enabling more accurate retrospective study of clinical phenomenon.

Machine learning analysis with population data for prepregnancy and perinatal risk factors for the neurodevelopmental delay of offspring

Neurodevelopmental disorders (NDD) in offspring are associated with a complex combination of pre-and postnatal factors. This study uses machine learning and population data to evaluate the association between prepregnancy or perinatal risk factors and the NDD of offspring. Population-based retrospective cohort data were obtained from Korea National Health Insurance Service claims data for 209,424 singleton offspring and their mothers who gave birth for the first time in 2007. The dependent variables were motor development disorder (MDD), cognitive development disorder (CDD) and combined overall neurodevelopmental disorder (NDD) from offspring. Seventeen independent variables from 2002 to 2007 were included. Random forest variable importance and Shapley Additive Explanation (SHAP) values were calculated to analyze the directions of its associations with the predictors. The random forest with oversampling registered much higher areas under the receiver-operating-characteristic curves than the logistic regression of interaction and non-linearity terms, 79% versus 50% (MDD), 82% versus 52% (CDD) and 74% versus 50% (NDD). Based on random forest variable importance, low socioeconomic status and age at birth were highly ranked. In SHAP values, there was a positive association between NDD and pre- or perinatal outcomes, especially, fetal male sex with growth restriction associated the development of NDD in offspring.

Receipt of and Satisfaction with School-based and Virtual Special Education Supports and Therapeutic Services During the COVID-19 Pandemic

The COVID-19 pandemic impacted school-based delivery of special educational supports and therapeutic services. This study describes student receipt of school-based supports/services and parent satisfaction by instruction modalities during the 2020-2021 academic year in the United States. Data were collected through the COVID Experiences Survey from parents of children ages 5-12 years, administered using NORC's AmeriSpeak panel. Most parents reported satisfaction with supports (88.4%) and services (93.2%). Dissatisfaction with special education supports and therapeutic services was more common among parents whose children received supports/services virtually than in person (special educational supports: aOR=12.00, 95% CI [1.49-96.89], p=0.020; therapeutic services: aOR=15.76, 95% CI [1.01-245.40], p=0.049). These findings suggest opportunities to improve design and delivery of online special education supports and therapeutic services as well as emergency preparedness by considering the needs of students with disabilities and their families.

Sex Differences in Low-Level Multisensory Integration in Developmental Dyslexia

Reading acquisition involves the integration of auditory and visual stimuli. Thus, low-level audiovisual multisensory integration might contribute to disrupted reading in developmental dyslexia. Although dyslexia is more frequently diagnosed in males and emerging evidence indicates that the neural basis of dyslexia might differ between sexes, previous studies examining multisensory integration did not evaluate potential sex differences nor tested its neural correlates. In the current study on 88 adolescents and young adults, we found that only males with dyslexia showed a deficit in multisensory integration of simple nonlinguistic stimuli. At the neural level, both females and males with dyslexia presented smaller differences in response to multisensory compared to those in response to unisensory conditions in the N1 and N2 components (early components of event-related potentials associated with sensory processing) than the control group. Additionally, in a subsample of 80 participants matched for nonverbal IQ, only males with dyslexia exhibited smaller differences in the left hemisphere in response to multisensory compared to those in response to unisensory conditions in the N1 component. Our study indicates that deficits of multisensory integration seem to be more severe in males than females with dyslexia. This provides important insights into sex-modulated cognitive processes that might confer vulnerability to reading difficulties.

Pedagogical practices and civic knowledge and engagement in Latin America: Multilevel analysis using ICCS data

This study explored the relationship between pedagogical practices and the civic knowledge and engagement of students from five Latin American and Caribbean countries, using a multilevel analysis of the 2016 International Civic and Citizenship Education Study (ICCS). The results reveal the complex interplay of educational, sociodemographic, and attitudinal factors in shaping the civic knowledge and engagement of students. Extracurricular civic engagement showed a negative correlation with student civic knowledge and engagement as measured by the ICCS cognitive test. However, civic learning in school positively related to cognitive abilities, emphasizing the importance of integrating civic learning into the curriculum. Interestingly, students' educational aspirations emerged as a significant factor shaping their civic engagement, suggesting a strategy to foster high educational aspirations to enhance cognitive performance. Additionally, gender dynamics were evident in civic education, with girls consistently outperforming boys in all participating countries. The correlation between home literacy resources and test scores illuminated the significant role of home environments in academic achievement. Lastly, students' attitudes towards political participation had a notable connection to civic knowledge outcomes, presenting an exciting avenue for future research. Collectively, these findings underscore the need for a comprehensive approach to civic education and further research to refine effective strategies.

The Role of Environmental Chemicals in the Etiology of Learning Difficulties: A Novel Theoretical Framework

Children from economically disadvantaged communities have a disproportionate risk of exposure to chemicals, social stress, and learning difficulties. Although animal models and epidemiologic studies link exposures and neurodevelopment, little focus has been paid to academic outcomes in environmental health studies. Similarly, in the educational literature, environmental chemical exposures are overlooked as potential etiologic factors in learning difficulties. We propose a theoretical framework for the etiology of learning difficulties that focuses on these understudied exogenous factors. We discuss findings from animal models and longitudinal, prospective birth cohort studies that support this theoretical framework. Studies reviewed point to the effects of prenatal exposure to polycyclic aromatic hydrocarbons on reading comprehension and math skills via effects on inhibitory control processes. Long term, this work will help close the achievement gap in the United States by identifying behavioral and neural pathways from prenatal exposures to learning difficulties in children from economically disadvantaged families.

Literacy skills seem to fuel literacy enjoyment, rather than vice versa

Children who like to read and write tend to be better at it. This association is typically interpreted as enjoyment impacting engagement in literacy activities, which boosts literacy skills. We fitted direction-of-causation models to partial data of 3690 Finnish twins aged 12. Literacy skills were rated by the twins' teachers and literacy enjoyment by the twins themselves. A bivariate twin model showed substantial genetic influences on literacy skills (70%) and literacy enjoyment (35%). In both skills and enjoyment, shared-environmental influences explained about 20% in each. The best-fitting direction-of-causation model showed that skills impacted enjoyment, while the influence in the other direction was zero. The genetic influences on skills influenced enjoyment, likely via the skills→enjoyment path. This indicates an active gene-environment correlation: children with an aptitude for good literacy skills are more likely to enjoy reading and seek out literacy activities. To a lesser extent, it was also the shared-environmental influences on children's skills that propagated to influence children's literacy enjoyment. Environmental influences that foster children's literacy skills (e.g., families and schools), also foster children's love for reading and writing. These findings underline the importance of nurturing children's literacy skills. HIGHLIGHTS: It's known that how much children enjoy reading and writing and how good they are at it correlates ∼0.30, but causality remains unknown. We tested the direction of causation in 3690 twins aged 12. Literacy skills impacted literacy enjoyment, but not the other way around. Genetics influence children's literacy skills and how much they like and choose to read and write, indicating genetic niche picking.

Sex differences in resting state functional connectivity across the first two years of life

Sex differences in behavior have been reported from infancy through adulthood, but little is known about sex effects on functional circuitry in early infancy. Moreover, the relationship between early sex effects on the functional architecture of the brain and later behavioral performance remains to be elucidated. In this study, we used resting-state fMRI and a novel heatmap analysis to examine sex differences in functional connectivity with cross-sectional and longitudinal mixed models in a large cohort of infants (n = 319 neonates, 1-, and 2-year-olds). An adult dataset (n = 92) was also included for comparison. We investigated the relationship between sex differences in functional circuitry and later measures of language (collected in 1- and 2-year-olds) as well as indices of anxiety, executive function, and intelligence (collected in 4-year-olds). Brain areas showing the most significant sex differences were age-specific across infancy, with two temporal regions demonstrating consistent differences. Measures of functional connectivity showing sex differences in infancy were significantly associated with subsequent behavioral scores of language, executive function, and intelligence. Our findings provide insights into the effects of sex on dynamic neurodevelopmental trajectories during infancy and lay an important foundation for understanding the mechanisms underlying sex differences in health and disease.

A Bayesian Probabilistic Framework for Identification of Individuals with Dyslexia

Purpose

Bayesian-based models for diagnosis are common in medicine but have not been incorporated into identification models for dyslexia. The purpose of the present study was to evaluate Bayesian identification models that included a broader set of predictors and that capitalized on recent developments in modeling the prevalence of dyslexia.

Method

Model-based meta-analysis was used to create a composite correlation matrix that included common predictors of dyslexia such as decoding, phonological awareness, oral language, but also included response to intervention (RTI) and family risk for dyslexia. Bayesian logistic regression models were used to predict poor reading comprehension, unexpectedly poor reading comprehension, poor decoding, and unexpectedly poor decoding, all at two levels of severity.

Results

Most predictors made independent and substantial contributions to prediction, supporting models of dyslexia that rely on multiple rather than single indicators. RTI was the strongest predictor of poor reading comprehension and unexpectedly poor reading comprehension. Phonological awareness was the strongest predictor of poor decoding and unexpectedly poor decoding, followed closely by family risk.

Conclusion

Bayesian-based models are a promising tool for implementing multiple-indicator models of identification. Ideas for improving prediction and implications for theory and practice are discussed.

Establishing childhood disability clinics may help reduce the prevalence of disability among children in Africa: A viewpoint

Globally, there are about a billion people comprising of about 95 million children who experience disability. The number of people in Africa living with disability is about 80 million people; out of which 10%-15% are children of school age. The causes of disability among these children include epilepsy, vision loss, or hearing loss, cerebral palsy, poliomyelitis, tetanus, cerebrospinal meningitis and malaria. However, these causes of disability are preventable and can be managed with proper care. The aim of this article is to propose the establishment of childhood disability clinics in Africa in order to help prevent or reduce the incidence/ prevalence of disability among children. Some of the mandates of the clinics will be to carry out routine assessment of children for disability, to provide education on disability and strategies for disability prevention to parents and caregivers, to promptly prevent and manage disability or its causes. However, establishing these clinics requires shared commitment of all the stakeholders.

Structural gray matter features and behavioral preliterate skills predict future literacy - A machine learning approach

When children learn to read, their neural system undergoes major changes to become responsive to print. There seem to be nuanced interindividual differences in the neurostructural anatomy of regions that later become integral parts of the reading network. These differences might affect literacy acquisition and, in some cases, might result in developmental disorders like dyslexia. Consequently, the main objective of this longitudinal study was to investigate those interindividual differences in gray matter morphology that might facilitate or hamper future reading acquisition. We used a machine learning approach to examine to what extent gray matter macrostructural features and cognitive-linguistic skills measured before formal literacy teaching could predict literacy 2 years later. Forty-two native German-speaking children underwent T1-weighted magnetic resonance imaging and psychometric testing at the end of kindergarten. They were tested again 2 years later to assess their literacy skills. A leave-one-out cross-validated machine-learning regression approach was applied to identify the best predictors of future literacy based on cognitive-linguistic preliterate behavioral skills and cortical measures in a priori selected areas of the future reading network. With surprisingly high accuracy, future literacy was predicted, predominantly based on gray matter volume in the left occipito-temporal cortex and local gyrification in the left insular, inferior frontal, and supramarginal gyri. Furthermore, phonological awareness significantly predicted future literacy. In sum, the results indicate that the brain morphology of the large-scale reading network at a preliterate age can predict how well children learn to read.

Reading and math skills development among Finnish primary school children before and after COVID-19 school closure

This study quantified the possible learning losses in reading and math skills among a sample of Finnish Grade 3 children (n = 198) who spent 8 weeks in distance learning during the first wave of the COVID-19 pandemic in spring 2020. We compared their reading and math skill development trajectories across Grades 1, 2, and 4 to a pre-COVID sample (N = 378). We also examined if gender, parental education, maternal homework involvement, and child's task-avoidant behavior predict children's academic skills at Grade 4 differently in the pre-COVID sample compared with the COVID sample. Children's reading and math skills were tested, mothers reported their education and homework involvement, and teachers rated children's task-avoidant behavior. The results showed, on average, lower reading skills in the COVID sample than in the pre-COVID sample but there were no differences in math skills. Although the COVID sample had lower levels in reading, their developmental trajectories in reading and math skills were not different from the pre-COVID sample before the pandemic in Grades 1 and 2. From Grade 2 to 4, however, the development was slower in reading fluency and comprehension in the COVID sample, but not in math. The predictors of change from Grade 2 to 4 in reading and math skills were not different in the samples. The results showed that the development of reading skills in particular may have been affected by the COVID-19 pandemic.

Association of Preexisting Mental Health Conditions With Increased Initial Symptom Count and Severity Score on SCAT5 When Assessing Concussion

Background:

Mental health conditions, such as depression, anxiety, and learning disabilities, are associated with symptoms that can overlap with those seen in persons with concussion. While concussion screening tools such as the Sport Concussion Assessment Tool–5th Edition (SCAT5) quantify the number of symptoms and symptom severity, it is not known whether these outcomes differ among individuals with concurrent mental health conditions compared with those without them.

Purpose:

To determine whether, during initial concussion assessment, individuals with a self-reported mental health condition have a significantly different number of self-reported concussion symptoms or symptom severity compared with those without a self-reported mental health condition (controls).

Study Design:

Cohort study; Level of evidence, 3.

Methods:

A retrospective chart review was performed on consecutive patients aged ≥13 years who underwent post-concussion assessment at the Fowler Kennedy Sport Medicine Clinic between May 2018 and March 2020 (N = 765). Most participants did not self-report a mental health condition (n = 606; 79.2%). Participants with a self-reported mental health condition (n = 159) were classified as having a learning disability (n = 14; 8.8%), anxiety (n = 62; 39.0%), depression (n = 20; 12.6%), or multiple conditions (≥2 conditions: n = 63; 39.6%). Each participant with a mental health condition was matched with 2 control participants (overall pool, n = 318) based on age, sex, student status, and sport-related risk. Mann-Whitney U tests were used to determine the statistical significance of differences between each subgroup and their matched controls for the self-reported number of concussion symptoms and symptom severity as measured using the SCAT5.

Results:

The anxiety and multiple-conditions subgroups had a significantly greater number of reported symptoms than their corresponding control subgroups (median, 17 vs 15 [P = .004] and 18 vs 14.5 [P < .001], respectively). Additionally, the SCAT5 symptom severity score was significantly greater in the anxiety and multiple-conditions subgroups than their corresponding controls (median, 49 vs 34.5 [P = .018] and 62 vs 32 [P < .001], respectively).

Conclusion:

During initial concussion assessment, both the number of concussion-related symptoms and the symptom severity were greater in study participants with anxiety and multiple mental health conditions than participants without these conditions.

Predicting and Evaluating Treatment Response: Evidence Toward Protracted Response Patterns for Severely Impacted Students With Dyslexia

Great strides have been made in the development of effective methods of instruction for children with dyslexia. However, individual response to treatment varies, and weaknesses persist for some students with dyslexia despite otherwise effective instruction. Continued efforts are needed to support the prospective identification of poor response, particularly in routine intervention settings. The current study addressed whether indicators of dyslexia risk as outlined by hybrid diagnostic models predict response in children who received Tier 3 dyslexia intervention in their schools. The program's efficacy has been previously documented in remediating reading abilities in children with dyslexia. Data were examined from 115 elementary-age children who received routine Tier 3 dyslexia intervention in their schools. Logistic regression revealed powerful effects of preintervention fluency and gender in predicting response, with weaker effects of decoding and rapid naming. Attention-deficit/hyperactivity disorder status also played a role in predicting response. Phonological awareness and listening-reading comprehension discrepancy did not predict response. Profile analyses indicated near- and far-transfer of skill for the adequate response group, whereas growth in the poor response group was limited to near-transfer. Findings support a continuum of severity that may be associated with less robust growth and generalization over the course of the intervention.

Exploring boundary conditions of the listening comprehension-reading comprehension discrepancy index

Conversations about the nature of dyslexia and how dyslexia impacts reading and listening comprehension get to the heart of classification and identification models of dyslexia. Recently, this conversation has been expanded to include efforts to estimate the prevalence of dyslexia in the population through the introduction of a discrepancy index of listening comprehension and reading comprehension. This discrepancy index was proposed to serve as a proxy for dyslexia when estimating its prevalence in the population. Individuals whose reading comprehension is considerably lower than their listening comprehension are thought to exhibit unexpected reading deficits. However, the index could underrepresent certain groups within the population. The current study explored this possibility using data from a sample of 4078 public-school students. We hypothesized that students from historically marginalized or otherwise disenfranchised groups (i.e., poor and minority groups) would be less likely to have a positive listening comprehension - reading comprehension (LC-RC) discrepancy index. Based on the results of multilevel linear mixed effect modeling, socioeconomic status (SES) contributed to differential performance on the discrepancy index when it was calculated using residual scores. Moreover, African American students were identified as having a reliably lower discrepancy index regardless of how it was calculated. It appears that this index, which only looks at the comprehension of language and not production, may, in fact, disadvantage students for whom oral language production differs from General American English (GAE). These outcomes suggest that this measure may lack the sensitivity to identify bidialectal students with dyslexia.

Beyond Simple Mean Differences: Analysis of Sex Similarities and Differences in Academic Achievement With the Kaufman Tests of Educational Achievement, Third Edition

Simple mean differences summarized in meta-analyses do not always adequately describe sex similarities and differences. We investigated sex similarities and differences in academic achievement test scores during childhood and adolescence multiple ways based on composite and subtest scores from the Kaufman Test of Educational Achievement (Third edition) norming sample. Sex differences in means were investigated across achievement domains and ability levels. Test score variance and percentages of scores at different parts of score distributions were also compared across sex. The largest and most consistent sex differences were female advantages in writing tests: Larger advantages were found in more complex writing tasks. Females also showed consistent advantages in silent reading fluency. Males demonstrated advantages in math problem solving that emerged at the average ability level. Females were more likely to be high achievers in reading fluency and written expression, whereas males were more likely to be low achievers in reading fluency and aspects of writing, and very low achievers in word recognition, word recognition fluency, and reading vocabulary. Males were more likely to be high achievers in math problem solving. Analysis that goes beyond simple mean differences reveals important sex differences regarding academic achievement, and theories should account for overall patterns of academic achievement similarities and differences.

Research Review: Language and specific learning disorders in children and their co-occurrence with internalizing and externalizing problems: a systematic review and meta-analysis

BACKGROUND

Some studies suggest that children with language and learning disorders (LLDs) show more internalizing and externalizing problems than their peers. However, the available evidence remains inconsistent, especially regarding the conditions under which these psychological problems occur.

METHODS

We performed a meta-analysis of studies comparing children with LLDs and controls on internalizing (53 independent samples, 135 effect sizes) and externalizing problems (37 independent samples, 61 effect sizes) separately.

RESULTS

Children with LLDs showed higher internalizing (Hedges' g = 0.36) and externalizing problems (Hedges' g = 0.42) than controls did. The group standardized difference in internalizing problems was moderated by the primary disorder, with children with language disorders showing more internalizing problems than those with reading disorders. The severity of the primary disorder, IQ, and age did not moderate Hedge's g between children with LLDs and controls in internalizing and externalizing outcomes. The same pattern was found for gender as a moderator of Hedge's g in internalizing problems, while findings for externalizing problems were inconclusive. The results were consistent when methodological variables were assessed, also for informant, sample size, and geographical area. Clinical samples with LLDs reported higher internalizing problems respect to those with difficulties, but findings on externalizing outcomes were limited. Similarly, results on the presence of additional symptoms in learning and language, self-concept, and socioeconomic status were inconclusive, as few studies reported this information. Results were robust when publication bias, publication year, and study quality were assessed.

CONCLUSIONS

There is evidence that children with LLDs report higher internalizing and externalizing problems than controls do. Children with language disorders seemed more vulnerable to report more internalizing problems, and clinical samples reported higher problems than those with difficulties. For clinical practice, assessment and interventions should target socioemotional skills to support the psychological well-being of children with LLDs.

Association between urinary dialkylphosphate metabolites and dyslexia among children from three cities of China: The READ program

Exposure to organophosphate (OP) insecticides has been found to be related to neurodevelopmental disorders in children. However, no study has examined the association between OP insecticide exposure and the risk of dyslexia among children. We aimed to explore the association between OP insecticide exposure, indicated by urinary dialkylphosphate metabolites (DAPs), and the risk of dyslexia among Chinese Han children from three cities. A total of 845 children (422 dyslexics and 423 non-dyslexics) from Tongji Reading Environment and Dyslexia research program were included in the current case-control study. We measured six DAPs in urine samples, collected from November 2017 to December 2020. Logistic regression models were used to estimate odds ratios (ORs) for the association between DAPs and dyslexia risk, adjusting for potential confounders. The detection frequencies of DAPs were above 97.5%, except for diethyldithiophosphate and dimethyldithiophosphate. Diethyl phosphate metabolites (DEs) were significantly associated with the risk of dyslexia. Compared with the lowest quartile, the adjusted ORs of dyslexia risk for the highest quartile of urinary diethylthiophosphate (DETP) and diethylphosphate (DEP) were 1.82 (1.04, 3.20) and 1.85 (1.08, 3.17), respectively. In addition, the adjusted ORs for dyslexia per 10-fold of urinary DEP, DETP, and ∑DEs concentration were 1.87 (1.12, 3.13), 1.55 (1.03, 2.35), and 1.91 (1.13, 3.21), respectively. Analyses stratified by gender indicated that such associations were more significant among boys. This study suggested that exposure to OP insecticides may be related to dyslexia among Chinese Han children from the three studied cities. However, our results should be interpreted with caution because of the case-control design and the fact that only one-spot urine sample was collected from the children. More studies with children living in China are necessary concerning the relatively high levels of urinary OP metabolites in our study.

The Role of Brain Activity in Characterizing Successful Reading Intervention in Children With Dyslexia

Studies of reading intervention in dyslexia have shown changes in performance and in brain function. However, there is little consistency in the location of brain regions associated with successful reading gains in children, most likely due to variability/limitations in methodologies (study design, participant criteria, and neuroimaging procedures). Ultimately for the results to be meaningful, the intervention has to be successful, be assessed against a control, use rigorous statistics, and take biological variables (sex) into consideration. Using a randomized, crossover design, 31 children with dyslexia were assigned to a phonological- and orthographic-based tutoring period as well as a within-subjects control period to examine: (1) intervention-induced changes in behavior (reading performance) and in brain activity (during reading); and (2) behavioral and brain activity pre-intervention data that predicted intervention-induced gains in reading performance. We found gains in reading ability following the intervention, but not following the control period, with no effect of participants' sex. However, there were no changes in brain activity following the intervention (regardless of sex), suggesting that individual brain changes are too variable to be captured at the group level. Reading gains were not predicted by pre-intervention behavioral data, but were predicted by pre-intervention brain activity in bilateral supramarginal/angular gyri. Notably, some of this prediction was only found in females. Our results highlight the limitations of brain imaging in detecting the neural correlates of reading intervention in this age group, while providing further evidence for its utility in assessing eventual success of intervention, especially if sex is taken into consideration.

Insights into Dyslexia Genetics Research from the Last Two Decades

Dyslexia, a specific reading disability, is a common (up to 10% of children) and highly heritable (~70%) neurodevelopmental disorder. Behavioral and molecular genetic approaches are aimed towards dissecting its significant genetic component. In the proposed review, we will summarize advances in twin and molecular genetic research from the past 20 years. First, we will briefly outline the clinical and educational presentation and epidemiology of dyslexia. Next, we will summarize results from twin studies, followed by molecular genetic research (e.g., genome-wide association studies (GWASs)). In particular, we will highlight converging key insights from genetic research. (1) Dyslexia is a highly polygenic neurodevelopmental disorder with a complex genetic architecture. (2) Dyslexia categories share a large proportion of genetics with continuously distributed measures of reading skills, with shared genetic risks also seen across development. (3) Dyslexia genetic risks are shared with those implicated in many other neurodevelopmental disorders (e.g., developmental language disorder and dyscalculia). Finally, we will discuss the implications and future directions. As the diversity of genetic studies continues to increase through international collaborate efforts, we will highlight the challenges in advances of genetics discoveries in this field.

Reading and spelling disorders in a school-based population screening in Sicily (Italy)

This research was carried out according to the Italian Consensus Conference on Specific Learning Disability guidelines for screening initiatives. It describes a three-year screening project involving 2.469 students, aged 8-15 years, from various classes of primary, lower and upper secondary schools of Sicily. Students were assessed for reading and spelling skills. Overall, 4.9% met the risk criteria for suspected reading disorder, 6.1% for spelling disorder, while 8.5% for both conditions. Results showed that out of 932 pupils in the primary school, 4.6% met the risk criteria for reading disorder and 6.5% for spelling disorder; out of 855 pupils of the lower secondary school, 5.3% for reading disorder and 5.5% for spelling disorder; out of 652 pupils of the upper secondary school, 4.9% for reading disorder and 6.1% for spelling disorder. No significant difference in the prevalence of students at risk of reading disorder or spelling disorder, within the three grade-levels over 3 years, was found. At project conclusion further clinical investigation to verify the screening results on student sub-sample (57%) was carried out. The percentage of students with SLD was equal to 3.15%, in the primary school, 3.76% in the lower secondary school and 2.51%, in the upper secondary school.

Sex and gender difference in cognitive and behavioral studies in developmental age: An introduction

This paper introduces a special issue focused on sex and gender (s/g) cognitive/behavioral differences at developmental ages providing an overview of this multifaceted and debated topic. It will provide a description of the biological systems that are strongly interconnected to generate s/g differences, that is, genetic determinants, sex hormones, differences in brain structure, organization, and/or function, inherited or modifiable under environmental pressures. Developmental studies are rare. Some addressed whether s/g differences in cognitive/behavioral characteristics are evident early in life and are consistent throughout development, entailing that s/g differences can follow the evolving steps in girls and boys in different domains. The data are far from being homogeneous and consistent about s/g difference in language, social skills, and visuo/spatial abilities. The differences are small, often with overlapping performances, similar to what is seen in adulthood. Given that several variables and the interactions between them are implicated, further longitudinal studies adopting adequate assessment tools, very large size multicultural samples stratified in different, well-sized and precise age groups, considering biological and sociocultural variables, are needed. Due to the complexity of the issue, there is still the need to support and adopt an s/g difference approach also in cognitive and behavioral studies at developmental ages. Finally, these studies have not only scientific importance and relevant cultural, anthropological, and social implications, but are also useful for pedagogical programming as well as for the study of the different susceptibility to develop CNS diseases and consequently to promote different therapies and treatments.

Sex-related differences in reading achievement

Over the last 40 years, ever-growing interest in sex-related differences in the human brain has led to a vast amount of literature on the subject, a small part of which relates to studies of differences in the ability to read. The data concerning typically developing children mainly come from school-based screening projects (Programme for International Student Assessment, INVALSI) and partially from the standardization of reading tests. These have revealed the existence of a gap in favor of females that primarily appears during adolescence and in situations of sociocultural disadvantage, usually explained on the basis of environmental factors such as socioeconomic status and gender-based education. Dyslexia is a neurodevelopmental disorder that is significantly more prevalent among males, a difference that neuroimaging and genetic studies have attributed to the presence of hormone-related protective factors in females, although it has been hypothesized that a different neurocognitive substrate may also be involved. However, the literature on the subject is still limited, and further studies of the interactions between genetic risk, environmental factors, and brain phenotypes are needed to clarify why females are better at performing reading tasks and less susceptible to dyslexia, regardless of their language or the educational system in the country in which they live. The aim of this mini-review was to describe the studies that have investigated sex-related differences in reading ability in both typically and atypically developing subjects.

How much testing can a kid take? Feasibility of collecting pediatric patient experience ratings of neuropsychological and psychological assessment

Parent-reported satisfaction is an important outcome measure in pediatric neuropsychology; however, self-report of patient experience following lengthy pediatric assessments has been under-investigated. Written at a first grade reading level and utilizing touch screen and read-aloud functionality, a set of 15 operationally-focused items were administered to evaluate pediatric patient experience of neuropsychological and psychological assessment. One-hundred ninety-seven clinically-referred patients (M age = 11.74, SD = 3.17, range = 5.86-19.02 years, 56% male) answered the post-assessment survey. The majority of patients (n = 167; 84.77%) accurately completed the initial two validity items, even though many had parent-reported ratings of reading difficulty. More than a third of patients indicated that the assessment made them tired (39%), but fewer patients reported feeling bored (13%) or worried (7%) during testing. Moreover, most patients reported having fun (66%) and many indicated that testing was preferable to other activities typically performed at that same time (i.e., school, homework). Responses to items assessing the child's interactions with the clinician and the child's effort provided little variation and were answered in a socially desirable manner. Items that focused upon the child's personal response to the assessment appointment (e.g., boredom, worry), however, elicited greater variance in patient responding. In general, patient responses did not suggest that assessment was an aversive experience. Overall, these proof of concept findings suggest that most referred pediatric patients, even those with learning issues, may be capable of independently navigating and completing self-report questionnaires while providing differential responses to items assessing clinical experience. Self-report questionnaires appear to be a feasible method for acquiring pediatric patient-reported experiences of assessment.

Neurocognitive disorders amongst patients with congenital heart disease undergoing procedures in childhood

BACKGROUND

Amongst children with congenital heart disease (CHD), earlier age of repair improves cardiovascular outcomes. The effects of early intervention on neurodevelopment remains unclear. We assessed the association between early life repair, cardiopulmonary bypass (CPB) and the incidence of neurocognitive disorders (NCD) amongst CHD patients.

METHODS

We created two retrospective cohorts from the Quebec CHD Database; with data from 1988 to 2010. Complexity of reparative procedures for CHD lesions were used as the proxy of CPB exposure with more complex procedure means longer exposure to CPB. Study Population 1 included pediatric patients with a single reparative procedure and compared patients with complex (long CBP) versus isolated shunt (short CBP) lesions. To assess the effects of CPB alone in Study Population 2 we compared patients with isolated atrial septal defects (ASD) who had surgical (short CBP) versus percutaneous (no CBP) repairs. The primary endpoint for both cohorts was development of an NCD.

RESULTS

In Study population 1, 1174 patients underwent complex surgical repair and 1620 had a shunt closure. The incidence of NCDs was 2.45/100 person-years in the complex surgery group, and 2.08/100 person-years in the shunt closure group. The following were associated with increased risk of developing a NCD: surgical complexity (Hazard Ratio [HR] = 1.20, 95% Confidence Interval [CI]: 1.01-1.42), younger age at intervention (AAI) (HR = 1.20, 95% CI: 1.16-1.25), male sex (HR = 1.91, 95% CI: 1.61-2.27), and later calendar year at intervention (HR = 1.06, 95% CI: 1.04-1.07). Study population 2 had 527 isolated ASD patients; 202 underwent surgical repair and 325 had percutaneous closure. The incidence of NCDs was not statistically different between groups. Male sex (HR = 1.77, 95% CI: 1.08-2.89) and younger AAI (HR = 1.15, 95% CI: 1.06-1.25) were associated with increased NCD risk.

CONCLUSION

Increased surgical complexity, male sex and younger AAI were associated with increased risk of NCDs in pediatric CHD patients. Surveillance protocols should be considered to identify NCDs in CHD patients after cardiac intervention.

The Polygenic Nature and Complex Genetic Architecture of Specific Learning Disorder

Specific Learning Disorder (SLD) is a multifactorial, neurodevelopmental disorder which may involve persistent difficulties in reading (dyslexia), written expression and/or mathematics. Dyslexia is characterized by difficulties with speed and accuracy of word reading, deficient decoding abilities, and poor spelling. Several studies from different, but complementary, scientific disciplines have investigated possible causal/risk factors for SLD. Biological, neurological, hereditary, cognitive, linguistic-phonological, developmental and environmental factors have been incriminated. Despite worldwide agreement that SLD is highly heritable, its exact biological basis remains elusive. We herein present: (a) an update of studies that have shaped our current knowledge on the disorder’s genetic architecture; (b) a discussion on whether this genetic architecture is ‘unique’ to SLD or, alternatively, whether there is an underlying common genetic background with other neurodevelopmental disorders; and, (c) a brief discussion on whether we are at a position of generating meaningful correlations between genetic findings and anatomical data from neuroimaging studies or specific molecular/cellular pathways. We conclude with open research questions that could drive future research directions.

Profiling the Word Reading Abilities of School-Age Children with Neurofibromatosis Type 1

OBJECTIVE

Reading difficulties are one of the most significant challenges for children with neurofibromatosis type 1 (NF1). The aims of this study were to identify and categorize the types of reading impairments experienced by children with NF1 and to establish predictors of poor reading in this population.

METHOD

Children aged 7-12 years with NF1 (n = 60) were compared with typically developing children (n = 36). Poor word readers with NF1 were classified according to impairment type (i.e., phonological, surface, mixed), and their reading subskills were compared. A hierarchical multiple regression was conducted to identify predictors of word reading.

RESULTS

Compared to controls, children with NF1 demonstrated significantly poorer literacy abilities. Of the 49 children with NF1 classified as poor readers, 20 (41%) were classified with phonological dyslexia, 24 (49%) with mixed dyslexia, and 5 (10%) fell outside classification categories. Children with mixed dyslexia displayed the most severe reading impairments. Stronger working memory, better receptive language, and fewer inattentive behaviors predicted better word reading skills.

CONCLUSIONS

The majority of children with NF1 experience deficits in key reading skills which are essential for them to become successful readers. Weaknesses in working memory, receptive language, and attention are associated with reading difficulties in children with NF1.

Annual Research Review: Reading disorders revisited - the critical importance of oral language

This paper discusses research on reading disorders during the period since their classification within the overarching category of neurodevelopmental disorders (Journal of Child Psychology and Psychiatry, 53, 2012, 593). Following a review of the predictors of learning to read across languages, and the role of language skills as critical foundations for literacy, profiles of reading disorders are discussed and putative causal risk factors at the cognitive, biological, and environmental levels of explanation considered. Reading disorders are highly heritable and highly comorbid with disorders of language, attention, and other learning disorders, notably mathematics disorders. The home literacy environment, reflecting gene-environment correlation, is one of several factors that promote reading development and highlight an important target for intervention. The multiple deficit view of dyslexia (Cognition, 101, 2006, 385) suggests that risks accumulate to a diagnostic threshold although categorical diagnoses tend to be unstable. Implications for assessment and intervention are discussed.

Two aspects of psychological functioning in undergraduates with a history of reading difficulties: anxiety and self-efficacy

Reading difficulties have been associated with problems in psychological functioning, including challenges in both anxiety and self-efficacy. This study was designed to determine whether such psychological functioning problems are specific to the academic sphere or more global. First-year undergraduate students with and without a history of reading difficulties (n = 40 and 46, respectively) completed standardized questionnaires on general and academic anxiety, and social and academic self-efficacy. Students with a history of reading difficulties reported higher academic anxiety, but comparable general anxiety, relative to those with no such history. Students with a history of reading difficulties also reported lower academic self-efficacy, but comparable social self-efficacy, relative to those with no such history. These findings suggest that students with a history of reading difficulties, as compared to those without such history, experience academic-specific mental health symptoms involving heightened anxiety and low self-efficacy as they enter university. These results point to the need for focused and targeted assessments to be able to capture difficulties they experience with anxiety and self-efficacy and interventions to help them cope with these difficulties. More broadly, the findings have implications for how universities assess academic vulnerabilities and provide access to specific course accommodations.

Sex Differences in Intelligence in Children Aged 2:6–7:7: Analysis of the Factor Structure and Measurement Invariance of the German Wechsler Primary and Preschool Scale of Intelligence–Fourth Edition

The present study investigated gender differences in cognitive abilities for children aged 2–7 years on the German Wechsler Primary and Preschool Scale of Intelligence–Fourth Edition (WPPSI-IV). WPPSI-IV data of 1,042 children (517 girls and 525 boys) were selected from the extended dataset of the German WPPSI-IV standardization sample. First of all, confirmatory factor analyses (CFAs) were used to verify the factor structure of the WPPSI-IV, which was proposed by the test developers. Then, multiple-group confirmatory factor models were implemented to explore measurement invariance across gender. Finally, mean differences in the subtests, index scores, as well as full scale IQ (FSIQ) were analyzed. The second-order three-factor model for age group 2:6–3:11 as well as the second-order five-factor model for age group 4:0–7:7 could be verified. For age group 2:6–3:11, full scalar invariance could be accepted, whereas partial scalar invariance could be established by freeing five nonequivalent subtest intercepts for age group 4:0–7:7. These findings support interpretable comparisons of the WPPSI-IV scores between girls and boys. For age group 4:0–7:7, partial invariance should be taken into account in these comparisons. Furthermore, girls aged 4:0–7:7 showed an advantage in processing speed (PS). Mean scores in any of the other cognitive abilities did not differ between girls and boys in both age groups. These results indicated measurement invariance across gender on the WPPSI-IV, so that the tests measure cognitive abilities in the same way for girls and boys. The current findings showed that gender differences in PS may emerge in early childhood, which might lead to gender differences in later educational skills.

The Phishing Email Suspicion Test (PEST) a lab-based task for evaluating the cognitive mechanisms of phishing detection

Phishing emails constitute a major problem, linked to fraud and exploitation as well as subsequent negative health outcomes including depression and suicide. Because of their sheer volume, and because phishing emails are designed to deceive, purely technological solutions can only go so far, leaving human judgment as the last line of defense. However, because it is difficult to phish people in the lab, little is known about the cognitive and neural mechanisms underlying phishing susceptibility. There is therefore a critical need to develop an ecologically valid lab-based measure of phishing susceptibility that will allow evaluation of the cognitive mechanisms involved in phishing detection. Here we present such a measure based on a task, the Phishing Email Suspicion Test (PEST), and a cognitive model to quantify behavior. In PEST, participants rate a series of phishing and non-phishing emails according to their level of suspicion. By comparing suspicion scores for each email to its real-world efficacy, we find initial support for the ecological validity of PEST - phishing emails that were more effective in the real world were more effective at deceiving people in the lab. In the proposed computational model, we quantify behavior in terms of participants' overall level of suspicion of emails, their ability to distinguish phishing from non-phishing emails, and the extent to which emails from the recent past bias their current decision. Together, our task and model provide a framework for studying the cognitive neuroscience of phishing detection.

Sex differences in subcortical auditory processing only partially explain higher prevalence of language disorders in males

Males and females differ in their subcortical evoked responses to sound. For many evoked response measures, the sex difference is driven by a faster developmental decline of auditory processing in males. Using the frequency-following response (FFR), an evoked potential that reflects predominately midbrain processing of stimulus features, sex differences were identified in the response to the temporal envelope of speech. The pattern of later and smaller responses in males versus females is consistent with two of the three response features that track with language development and reading abilities. Therefore, here we analyzed subcortical response consistency, the third distinguishing feature of language ability. Furthermore, though the envelope is primarily a low-frequency response, the greatest sex differences were observed in harmonics encoding. To better understand these sex differences, we extended these findings to the temporal fine structure response, which is biased to high-frequency information. Using the same 516 participants as previously reported (Krizman et al., 2019), we analyzed the effect of sex across development on response consistency and the encoding of temporal fine structure, as indexed by the subtracted frequency-following response. We found that while males and females did not differ on response consistency, there was an effect of age on this measure. Moreover, while males still showed a faster decline in harmonic encoding, the magnitude and breadth of the sex differences were smaller (accounting for 2% variance) in the temporal fine structure response compared to the envelope response. These results suggest that sex differences are distinct, at least in part, from the differences that underlie language abilities and that developmental sex differences reflect subcortical auditory processing differences of both the temporal envelope and fine structure of sounds.

Educational and learning morbidity in pediatric heart transplant recipients: A pediatric heart transplant society study

Educational development is an important component of quality of life for children with heart transplant. Aims include determining prevalence of and risk factors for modified education placement in a large representative sample of pediatric heart transplant recipients. Participants included 1495 patients (age 6-18 years) from the PHTS database. Data on education placement and clinical predictors were collected at listing and at 1 and 3 years post-transplant. At listing, 88% of patients were in typical education placement, while 12% were in modified education. Males (P = .02), those with CHD (P < .0001), those with non-private insurance (P < .0001), and those with longer hospital stay (P = .001) were more likely to be in a modified education placement at time of listing. Age, race, listing status, mechanical support, and waitlist time were not significantly associated with placement. The prevalence of typical education placement was similar (87% at 1-year and 86% at 3-year) post-transplant. Predictors of modified education placement at 3-year follow-up included placement at listing (OR = 12.9 [95% CI 7.6-21.9], P < .0001), non-private insurance (OR = 2.0 [95% CI 1.3-3.2], P = .001), CHD (OR = 1.8 [95% CI 1.1-2.7, P = .01), history of post-transplant infection (OR = 1.9 [95% CI 1.2-2.9, P = .007), and number of post-transplant infections (OR = 1.3 [95% CI 1.1-1.5, P = .002). Among pediatric heart transplant recipients, males, those with non-private insurance, those with CHD, and those who experience post-transplant infections are at greatest risk for modified academic placement, which persists for several years post-transplant and deserves targeted intervention.

The Prevalence of Dyslexia: A New Approach to Its Estimation

How prevalent is dyslexia? A definitive answer to this question has been elusive because of the continuous distribution of reading performance and predictors of dyslexia and because of the heterogeneous nature of samples of poor readers. Samples of poor readers are a mixture of individuals whose reading is consistent with or expected based on their performance in other academic areas and in language, and individuals with dyslexia whose reading is not consistent with or expected based on their other performances. In the present article, we replicate and extend a new approach for determining the prevalence of dyslexia. Using model-based meta-analysis and simulation, three main results were found. First, the prevalence of dyslexia is better represented as a distribution that varies as a function of severity as opposed to any single-point estimate. Second, samples of poor readers will contain more expected poor readers than unexpected or dyslexic readers. Third, individuals with dyslexia can be found across the reading spectrum as opposed to only at the lower tail of reading performance. These results have implications for screening and identification, and for recruiting participants for scientific studies of dyslexia.

The effects of gender and academic achievement on reading fluency among Year 2 Malaysian school children

OBJECTIVE

Language disorders can affect reading skills contributing to poor academic achievements. As such, it is vital for speech language pathologists to identify the potential language-based reading problems among children. To achieve this, specific reading assessments should be developed and studied. Thus, the present study aimed to determine the effects of gender and academic achievement on oral reading fluency (ORF) and silent reading fluency (SRF) among Year 2 Malaysian children.

METHODS

In this study that employed a comparative design, fifty-nine typically developing Malaysian children (24 boys, aged from 8 years, 0 months to 8 years, 11 months) were enrolled. They were chosen from three different classrooms (consisting of high achieving, medium achieving and low achieving students, respectively) in a primary school. Their ORF and SRF skills were assessed according to the established methods.

RESULTS

As revealed by two-way ANOVA results, both ORF and SRF scores were found to be comparable between boys and girls (p > 0.05). In contrast, ORF and SRF results between the three classrooms were significantly different from each other (p < 0.05).

CONCLUSION

The present study provides the first report on oral and silent reading fluency skills among Year 2 Malaysian school children. While the gender effect was insignificant, low achieving students showed poorer reading fluency skills. The preliminary normative data for ORF and SRF provided by the present study are beneficial for future research applications.

Relations Among Executive Function, Decoding, and Reading Comprehension: An Investigation of Sex Differences

In the current investigation, we used structural equation mediation modeling to examine the relations between executive function (indexed by measures of working memory, shifting, and inhibition), decoding ability, and reading comprehension in a sample of 298 6- to 8-year-old children (N =132 and 166 for boys and girls, respectively). Results for the full sample indicated that executive function was mediated by decoding ability. When sex was examined as a moderator of these associations, there was evidence for a trend suggesting that direct relations between executive function and reading comprehension were stronger for girls compared to boys; no significant differences were found for other direct and indirect relations. Taken together, these findings highlight the importance of executive function in supporting underlying integrative processes associated with reading comprehension and emphasize the need to further consider the role of executive function in relation to reading.

First and Second Language Reading Difficulty Among Chinese-English Bilingual Children: The Prevalence and Influences From Demographic Characteristics

Learning to read a second language (L2) can pose a great challenge for children who have already been struggling to read in their first language (L1). Moreover, it is not clear whether, to what extent, and under what circumstances L1 reading difficulty increases the risk of L2 reading difficulty. This study investigated Chinese (L1) and English (L2) reading skills in a large representative sample of 1,824 Chinese-English bilingual children in Grades 4 and 5 from both urban and rural schools in Beijing. We examined the prevalence of reading difficulty in Chinese only (poor Chinese readers, PC), English only (poor English readers, PE), and both Chinese and English (poor bilingual readers, PB) and calculated the co-occurrence, that is, the chances of becoming a poor reader in English given that the child was already a poor reader in Chinese. We then conducted a multinomial logistic regression analysis and compared the prevalence of PC, PE, and PB between children in Grade 4 versus Grade 5, in urban versus rural areas, and in boys versus girls. Results showed that compared to girls, boys demonstrated significantly higher risk of PC, PE, and PB. Meanwhile, compared to the 5th graders, the 4th graders demonstrated significantly higher risk of PC and PB. In addition, children enrolled in the urban schools were more likely to become better second language readers, thus leading to a concerning rural-urban gap in the prevalence of L2 reading difficulty. Finally, among these Chinese-English bilingual children, regardless of sex and school location, poor reading skill in Chinese significantly increased the risk of also being a poor English reader, with a considerable and stable co-occurrence of approximately 36%. In sum, this study suggests that despite striking differences between alphabetic and logographic writing systems, L1 reading difficulty still significantly increases the risk of L2 reading difficulty. This indicates the shared meta-linguistic skills in reading different writing systems and the importance of understanding the universality and the interdependent relationship of reading between different writing systems. Furthermore, the male disadvantage (in both L1 and L2) and the urban-rural gap (in L2) found in the prevalence of reading difficulty calls for special attention to disadvantaged populations in educational practice.

Sex differences in early communication development: behavioral and neurobiological indicators of more vulnerable communication system development in boys

Perhaps due to different roles they have had in social groups during evolution, men and women differ in their verbal abilities. These differences are also (if not even more) present in children, both in the course of typical and pathological development. Beside the fact that girls have a well-documented advantage in early language development, almost all developmental disorders primarily affecting communication, speech, and language skills are more frequent in boys. The sex-related difference in the prevalence of these disorders is especially pronounced in autism spectrum disorder (1 girl for each 4-5 boys is affected). The aim of this review is to present the sex differences in typical communication and language development and in the prevalence of communication-related neurodevelopmental disorders. Also, a special focus is put on data from the field of neuroscience that might provide insight into the neurobiological mechanisms that can add to the understanding of this phenomenon. We argue that the functional organization of the female brain gives women an inherent advantage in the acquisition of communication and language system over men.

Combining Old and New for Better Understanding and Predicting Dyslexia

Despite decades of research, it has been difficult to achieve consensus on a definition of common learning disabilities such as dyslexia. This lack of consensus represents a fundamental problem for the field. Our approach to addressing this issue is to use model-based meta-analyses and Bayesian models with informative priors to combine the results of a large number of studies for the purpose of yielding a more stable and well-supported conceptualization of reading disability. A prerequisite to implementing these models is establishing informative priors for dyslexia. We illustrate a new approach for doing so based on the known distribution of the difference between correlated variables, and use this distribution to determine the proportion of poor readers whose poor reading is unexpected (i.e., likely to be due to dyslexia) as opposed to expected.

Sex differences in early communication development: behavioral and neurobiological indicators of more vulnerable communication system development in boys

Perhaps due to different roles they have had in social groups during evolution, men and women differ in their verbal abilities. These differences are also (if not even more) present in children, both in the course of typical and pathological development. Beside the fact that girls have a well-documented advantage in early language development, almost all developmental disorders primarily affecting communication, speech, and language skills are more frequent in boys. The sex-related difference in the prevalence of these disorders is especially pronounced in autism spectrum disorder (1 girl for each 4-5 boys is affected). The aim of this review is to present the sex differences in typical communication and language development and in the prevalence of communication-related neurodevelopmental disorders. Also, a special focus is put on data from the field of neuroscience that might provide insight into the neurobiological mechanisms that can add to the understanding of this phenomenon. We argue that the functional organization of the female brain gives women an inherent advantage in the acquisition of communication and language system over men.

The Role of Learning Difficulties in Adolescents' Academic Emotions and Academic Achievement

The present study examines associations between learning difficulties (LD), academic emotions, and academic achievement among 845 Grade 6 adolescents (455 girls, 390 boys). Reading difficulties (RD) and math difficulties (MD) were identified based on tested reading and math skills in the fall semester of Grade 6. At this time, the students also rated their hope, enjoyment, and anxiety regarding literacy and math. Information on students' achievement in literacy and math, as well as their overall academic achievement, was gathered using questionnaires in both the fall and spring semesters of Grade 6. The results show, first, that students with RD had lower hope and higher anxiety toward reading than those without RD. Also, students with MD reported lower enjoyment, lower hope, and higher anxiety than those without MD. Furthermore, the results show that hope partly played a mediating role between LD and academic achievement in both the literacy and math domains. In addition, enjoyment played a mediating role in the math domain. The present study's results indicate that subject-specific academic emotions should be taken into account when considering relations between LD and academic achievement.

Neurobiological Sex Differences in Developmental Dyslexia

Understanding sex differences at the neurobiological level has become increasingly crucial in both basic and applied research. In the study of developmental dyslexia, early neuroimaging investigations were dominated by male-only or male-dominated samples, due at least in part to males being diagnosed more frequently. While recent studies more consistently balance the inclusion of both sexes, there has been little movement toward directly characterizing potential sex differences of the disorder. However, a string of recent work suggests that the brain basis of dyslexia may indeed be different in males and females. This potential sex difference has implications for existing models of dyslexia, and would inform approaches to the remediation of reading difficulties. This article reviews recent evidence for sex differences in dyslexia, discusses the impact these studies have on the understanding of the brain basis of dyslexia, and provides a framework for how these differential neuroanatomical profiles may develop.

Relationship between phonological working memory, metacognitive skills and reading comprehension in children with learning disabilities

PURPOSE

Reading requires the activation of several cognitive processes, some of which are basic, e.g. recognizing letters and words, whereas others are complex, such as working memory and ability to think about one's own learning strategies. One condition for fulfilling a complex cognitive task, such as understanding a text, is the ability to maintain and process information, which depends on working memory.

OBJECTIVE

To analyze the ability of using metacognitive strategies for reading, the phonological working memory of school children with learning disabilities, and also determine if there is relation between these skills and reading comprehension.

METHOD

The sample consisted of 30 school-age children and teenagers of both genders, aged 8 to 12 years, who were enrolled in primary school. They were divided in two groups, experimental (EG) and control (CG). All children were subjected to evaluation of reading comprehension, phonological working memory, and use of metacognitive skills for reading. The results were compared between groups through the Mann-Whitney test, and correlation between variables was analyzed through Spearman correlation test.

RESULT

Statistical comparison between EG and CG showed statistically significant difference. Positive and effective correlation was observed between reading comprehension, phonological working memory and metacognitive tests.

CONCLUSION

children with learning disabilities presented deficits in phonological working memory and use of metacognitive strategies. The positive and effective correlation between the abilities analyzed suggests that failure in the phonological working memory and use of metacognitive strategies interfere with reading comprehension.

Genetic variants in the CNTNAP2 gene are associated with gender differences among dyslexic children in China

Background

It is well known that males have a higher prevalence of developmental dyslexia (DD) than females. Although the mechanism underlying this gender difference remains unknown, the contactin-associated protein-like 2 (CNTNAP2) gene, which shows sex-specific patterns in some neurodevelopmental disorders, has attracted extensive attention. This study aimed to explore whether CNTNAP2 shows a sex-specific association with DD in a Chinese population.

Methods

Using genomic DNA samples of 726 students [372 cases (282 male, 90 female), 354 controls (267 male, 87 female)], we genotyped five SNPs of CNTNAP2. Gender-stratified logistic regression models were used to determine the relationships between the CNTNAP2 variants and DD.

Findings

After adjustment for the false discovery rate (FDR), two SNPs (rs3779031, rs987456) of CNTNAP2 were associated with DD risk in females but not in males. Female participants carrying the rs3779031 G allele had a lower risk of DD than those with the A genotype [GG vs AA: OR (95%CI) = 0.281 (0.097–0.814)]. The rs987456 CC genotype was associated with a decreased risk of DD in females [CC vs AA+CA: OR (95%CI) = 0.222 (0.078–0.628)]. Furthermore, the interaction between CNTNAP2 (rs987456) and environmental factors (scheduled reading time) played a protective role in females [OR (95%CI) = 0.431 (0.188–0.987)].

Interpretation

We performed a genetic association study on CNTNAP2 variants and DD. The sex specificity of CNTNAP2 in DD, along with the gene-environment interaction may help us to understand gender differences in DD.

Reading Self-Concept and Reading Anxiety in Second Grade Children: The Roles of Word Reading, Emergent Literacy Skills, Working Memory and Gender

Background: Most studies in the field of reading have focused on the linguistic and cognitive factors. Less is known about the affective aspects of reading in young readers, such as self-perceptions of reading, and reading anxiety. Aims: This study aimed to shed light on the direct and indirect relations between reading and related skills (working memory, emergent literacy skills, word reading accuracy and rate, and gender) as sources of reading affect (reading self-concept and anxiety). Sample: A total of 115 Hebrew speaking second graders participated in this study. Methods: A set of measures assessing reading accuracy and rate, emergent literacy skills (phonological fluency, rapid automatized naming and working memory) and reading affect questionnaires (reading self-concept and reading anxiety) were administered to the participants. Results: Path analysis was used as the primary analytic approach. Results indicated a negative moderate relation between reading self-concept and reading anxiety. The relations of working memory and emergent literacy to reading self-concept and reading anxiety were indirect via word reading accuracy and reading rate. Girls reported higher reading anxiety and lower reading self-concept, despite higher performance in reading accuracy and no difference in reading rate. Conclusion: The current results support the importance of examining reading affect and potential sources of reading affect. Results suggest that reading self-concept and reading anxiety and their related skills should be considered in designing reading intervention and instructions.

Prevalence of Developmental Dyslexia in Spanish University Students

A recent concern in the field of dyslexia studies is the lack of awareness and attention to university students suffering from this condition. If this problem is serious in countries where the relative opacity of the writing system allows for an early detection and, therefore, effective interventions, it is most critical in countries where transparent spelling makes such detection difficult, except in the most severe cases. In Spain, the diagnosis of dyslexia is rare among university-level adults. The present study pursues three aims: (a) to put forward a screening instrument for the detection of university students at risk of dyslexia, (b) to determine the ratio of university students that could be at risk of dyslexia by means of two different procedures, and (c) to create awareness for a disorder that causes hitherto unrecognized difficulties for an important subgroup of the college population. Six hundred and eighty-six university students in four different fields of study within the general area of Social Sciences from a public University in Madrid completed a Spanish-adapted version of a protocol including stress assignment, spelling words and nonwords, and timed phonological working memory of reading and writing task. Results showed that between 1.6% and 6.4% of this population could be at risk of suffering dyslexia. Such risk is not evenly distributed across the four fields of study. As for gender, the first criterion used yields 1.8 males at risk for every female, but the second criterion has as many males as females at risk. Women were significantly better than men in word spelling. Spelling was best predicted by the timed phonological working memory task of reading and writing.

Differential Identification of Females and Males with Reading Difficulties: A Meta-Analysis

Males are more likely than females to be identified as having reading difficulties, but it is unclear if this is a result of sample ascertainment or identification bias. The purpose of this meta-analysis was to determine the magnitude of gender differences in reading difficulties using available studies in which researchers investigated this difference and an additional dataset with a representative U.S.

SAMPLE

After conducting a literature search, sixteen studies and a restricted use dataset were included in the present analysis (N = 552,729). A random-effects odds ratio (OR) model indicated that males are 1.83 times more likely than females to have reading difficulties. Moderator analyses revealed that the gender ratio is greater when the identified reading difficulties were more severe. Further, this difference in identification rates across males and females was found without evidence of publication bias. Implications for the identification of students with reading difficulties are discussed.

Does Use of Text-to-Speech and Related Read-Aloud Tools Improve Reading Comprehension for Students With Reading Disabilities? A Meta-Analysis

Text-to-speech and related read-aloud tools are being widely implemented in an attempt to assist students' reading comprehension skills. Read-aloud software, including text-to-speech, is used to translate written text into spoken text, enabling one to listen to written text while reading along. It is not clear how effective text-to-speech is at improving reading comprehension. This study addresses this gap in the research by conducting a meta-analysis on the effects of text-to-speech technology and related read-aloud tools on reading comprehension for students with reading difficulties. Random effects models yielded an average weighted effect size of ([Formula: see text] = .35, with a 95% confidence interval of .14 to .56, p < .01). Moderator effects of study design were found to explain some of the variance. Taken together, this suggests that text-to-speech technologies may assist students with reading comprehension. However, more studies are needed to further explore the moderating variables of text-to-speech and read-aloud tools' effectiveness for improving reading comprehension. Implications and recommendations for future research are discussed.