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To better understand the implications of comorbidity between reading disability (RD) and attention-deficit/hyperactivity disorder (ADHD), a sample of 225 participants with RD but without ADHD, 139 participants with both RD and ADHD, and 1,502 children without reading or attentional difficulties was recruited through five large public school districts. In comparison to the group without RD or ADHD, both groups with RD exhibited elevations of comorbid internalizing and externalizing disorders and significant global, academic, and social impairment. However, the group with both RD and ADHD was most impaired on most measures, and analyses of neuropsychological measures indicate that the co-occurrence of RD and ADHD may be due at least in part to weaknesses in cognitive processing speed and working memory that are most severe in the comorbid group. These results indicate that psychoeducational assessments of RD should always screen for ADHD and other emotional and behavioral difficulties, and that when RD and ADHD co-occur interventions are likely to be needed for both disorders.

This paper reviews three studies investigating the relationship between brain regions involved in executive control and those involved in reading comprehension in typically-developing teens. In the first study, three regions of posterior left lateral prefrontal cortex (i.e., precentral gyrus, inferior frontal junction, inferior frontal gyrus) were consistently activated across three task domains: reading comprehension, numerical estimation, and executive processes in working memory, suggesting these regions exert domain-general executive control. In a second study, brain activity in the precentral gyrus during reading comprehension was found to be associated with individual differences in reading achievement. A subsequent investigation indicated that while all three prefrontal regions exhibit greater connectivity to the angular gyrus during reading comprehension compared to symbol identification, each also exhibits unique connectivity to distinct posterior regions implicated in reading processes. Hence, reading difficulties during adolescence may arise, in part, from difficulties in executive control over processing in language-related brain regions.

Introduction: Children born prematurely often score lower on standardized tests of language in early childhood. Less is known about longer term outcomes. This investigation considered language outcomes in pre-adolescent children born very preterm/very low birthweight, as assessed by both standardized test scores and language sample measures, and explored attention abilities as a possible moderating factor. Method: The present investigation provided a longitudinal follow-up to Mahurin Smith et al. (2014) by examining the language outcomes of 84 children at the 11-year time point (39 with a history of prematurity and 45 born at full term) and a total of 82 at the 12-year time point (37 with a history of prematurity, 45 born at full term). Assessments included subtests of the Clinical Evaluation of Language Fundamentals--Fourth Edition, productive language measures taken from narrative tasks, and parent and examiner ratings of attention. Results: Gestational age significantly predicted standardized language scores at age 11 years, but this effect was no longer statistically significant at age 12 years. When parent ratings of attention were considered as additional variables, gestational age was no longer a significant predictor. Gestational age did not serve as a significant predictor for the productive language measures at either time point. Discussion: Results indicate that catch-up growth in language may take place in pre-adolescence for many children born prematurely. Clinical implications focus on the need to utilize multiple forms of language assessment and to directly consider the potential role of attention on standard test results.

Background: The number line task assesses the ability to estimate numerical magnitudes. People vary greatly in this ability, and this variability has been previously associated with mathematical skills. However, the sources of individual differences in number line estimation and its association with mathematics are not fully understood. Aims: This large-scale genetically sensitive study uses a twin design to estimate the magnitude of the effects of genes and environments on: (1) individual variation in number line estimation and (2) the covariation of number line estimation with mathematics. Samples: We used over 3,000 8- to 16-year-old twins from the United States, Canada, the United Kingdom, and Russia, and a sample of 1,456 8- to 18-year-old singleton Russian students. Methods: Twins were assessed on: (1) estimation of numerical magnitudes using a number line task and (2) two mathematics components: fluency and problem-solving. Results: Results suggest that environments largely drive individual differences in number line estimation. Both genes and environments contribute to different extents to the number line estimation and mathematics correlation, depending on the sample and mathematics component. Conclusions: Taken together, the results suggest that in more heterogeneous school settings, environments may be more important in driving variation in number line estimation and its association with mathematics, whereas in more homogeneous school settings, genetic effects drive the covariation between number line estimation and mathematics. These results are discussed in the light of development and educational settings.

The strategy choice model (SCM) is a highly influential theory of human problem-solving. One strength of this theory is the allowance for both item and person variance to contribute to problem-solving outcomes, but this central tenet of the model has not been empirically tested. Explanatory item response theory (EIRT) provides an ideal approach to testing this core feature of SCM, as it allows for simultaneous estimation of both item and person effects on problem-solving outcomes. We used EIRT to test and confirm this central tenet of the SCM for adolescents' (n = 376) solving of addition problems. The approach also allowed us to identify the strategy choices of adolescents who still struggle with basic arithmetic. The synthesis of SCM theory and EIRT modeling has implications for more fully investigating the sources of individual differences in students' problem solving, and for identifying problem-solving patterns associated with poor academic achievement. [For the corresponding grantee submission, see ED617646.]

We investigated the extent to which working memory and behavioral attention predicted reading and listening comprehension in grades 1 through 3 and, whether their relative contributions differed by modality and grade. Separate grade samples (N = 370; ns = 125, 123, and 122 for grades 1, 2, and 3 respectively) completed multiple measures of word reading, working memory, and parallel measures of reading and listening comprehension. Teachers and parents provided behavioral attention ratings. Concurrently, working memory was more important for listening than for reading comprehension and predicted significant variance in both modalities across grades, after controlling for background measures and behavioral attention ratings. For both modalities, working memory explained the greatest proportion of variance in grade 3. Behavioral attention predicted variance in grades 1 and 2 for reading comprehension and all grades for listening comprehension. Subsidiary analyses demonstrated that the influence of working memory and behavioral attention on reading comprehension was indirect, through word reading and listening comprehension both concurrently and also longitudinally between grades 1-3. These findings indicate that delivery of classroom materials orally will not always be beneficial to the young beginner reader or one who struggles with word decoding, and that children with poor working memory/attention may require additional support to access meaning from both written and spoken text.

Purpose: This research note explores the potential role of attention in mediating previously reported associations between language outcomes and prematurity. Method: As a follow-up investigation to Mahurin Smith, DeThorne, Logan, Channell, and Petrill (2014), we employed multilevel modeling to analyze longitudinal data on language and attention collected when children were, on average, ages of 7, 8, and 10 years. The sample of 114 children taken from the Western Reserve Reading and Math Project was selected to oversample children with a history of prematurity while also controlling for differences in confounding influences such as age, gender, parental education, and race. Results: As predicted, attention differentially predicted language outcomes based on form of measurement. Specifically, parent and examiner ratings of attention were significantly associated with standardized test performance at all 3 time points (R[superscript 2] = 15.2%-20%). Associations between attention and language sample measures were less consistent across home visits and tended to be smaller in effect size. Conclusion: Attention abilities are associated with children's language performance even in the absence of an attention-deficit/hyperactivity disorder diagnosis. Clinical implications, particularly as related to assessment, are discussed.

Individual differences in number sense correlate with mathematical ability and performance, although the presence and strength of this relationship differs across studies. Inconsistencies in the literature may stem from heterogeneity of number sense and mathematical ability constructs. Sample characteristics may also play a role as changes in the relationship between number sense and mathematics may differ across development and cultural contexts. In this study, 4,984 16-year-old students were assessed on estimation ability, one aspect of number sense. Estimation was measured using 2 different tasks: number line and dot-comparison. Using cognitive and achievement data previously collected from these students at ages 7, 9, 10, 12, and 14, the study explored for "which" of the measures and "when" in development these links are observed, and "how" strong these links are and how much these links are moderated by other cognitive abilities. The 2 number sense measures correlated modestly with each other (r = .22), but moderately with mathematics at age 16. Both measures were also associated with earlier mathematics; but this association was uneven across development and was moderated by other cognitive abilities.

Socioeconomic risks (SES risks) are robust risk factors influencing children's academic development. However, it is unclear whether the effects of SES on academic development operate universally in all children equally or whether they vary differentially in children with particular characteristics. The current study aimed to explore children's temperament as protective or risk factors that potentially moderate the associations between SES risks and academic development. Specifically, latent growth modeling (LGM) was used in two longitudinal datasets with a total of 2236 children to examine how family SES risks and children's temperament interactively predicted the development of reading and math from middle childhood to early adolescence. Results showed that low negative affect, high effortful control, and low surgency mitigated the negative associations between SES risks and both reading and math development in this developmental period. These findings underline the heterogeneous nature of the negative associations between SES risks and academic development and highlight the importance of the interplay between biological and social factors on individual differences in development.

Extant literature has established a consistent association between aspects of reading motivation, such as enjoyment and self-perceived ability, and reading achievement, in that more motivated readers are generally more skilled readers. However, the developmental etiology of this relation is yet to be investigated. The present study explores the development of the motivation-achievement association and its genetic and environmental underpinnings. Applying cross-lagged design in a sample of 13,825 twins, we examined the relative contribution of genetic and environmental factors to the association between reading enjoyment and self-perceived ability and reading achievement. Children completed a reading comprehension task and self-reported their reading enjoyment and perceived ability twice in middle childhood: when they were 9-10 and 12 years old. Results showed a modest reciprocal association over time between reading motivation (enjoyment and perceived ability) and reading achievement. Reading motivation at age 9-10 statistically predicted the development of later achievement, and similarly, reading achievement at age 9-10 predicted the development of later motivation. This reciprocal association was observed beyond the stability of the variables and their contemporaneous correlation and was largely explained by genetic factors.

Little is known about the neural correlates of expository text comprehension. In this study, we sought to identify neural networks underlying expository text comprehension, how those networks change over the course of comprehension, and whether information central to the overall meaning of the text is functionally distinct from peripheral information. Seventeen adult subjects read expository passages while being scanned using functional magnetic resonance imaging (fMRI). By convolving phrase onsets with the hemodynamic response function (HRF), we were able to identify regions that increase and decrease in activation over the course of passage comprehension. We found that expository text comprehension relies on the co-activation of the semantic control network and regions in the posterior midline previously associated with mental model updating and integration [posterior cingulate cortex (PCC) and precuneus (PCU)]. When compared to single word comprehension, left PCC and left Angular Gyrus (AG) were activated only for discourse-level comprehension. Over the course of comprehension, reliance on the same regions in the semantic control network increased, while a parietal region associated with attention [intraparietal sulcus (IPS)] decreased. These results parallel previous findings in narrative comprehension that the initial stages of mental model building require greater visuospatial attention processes, while maintenance of the model increasingly relies on semantic integration regions. Additionally, we used an event-related analysis to examine phrases central to the text's overall meaning vs. peripheral phrases. It was found that central ideas are functionally distinct from peripheral ideas, showing greater activation in the PCC and PCU, while over the course of passage comprehension, central and peripheral ideas increasingly recruit different parts of the semantic control network. The finding that central information elicits greater response in mental model updating regions than peripheral ideas supports previous behavioral models on the cognitive importance of distinguishing textual centrality.

Purpose: We evaluated genetic and environmental contributions to individual differences in language skills during early adolescence, measured by both language sampling and standardized tests, and examined the extent to which these genetic and environmental effects are stable across time. Purpose: We evaluated genetic and environmental contributions to individual differences in language skills during early adolescence, measured by both language sampling and standardized tests, and examined the extent to which these genetic and environmental effects are stable across time. Results: Individual differences in the Formal Language factor were influenced primarily by genetic factors at each age, whereas individual differences in the Productive Language factor were primarily due to nonshared environmental influences. For the Formal Language factor, the stability of genetic effects was high across all 3 time points. For the Productive Language factor, nonshared environmental effects showed low but statistically significant stability across adjacent time points. Conclusions: The etiology of language outcomes may differ substantially depending on assessment context. In addition, the potential mechanisms for nonshared environmental influences on language development warrant further investigation.

Skilled reading depends on recognizing words efficiently in isolation ("word-level processing"; "WL") and extracting meaning from text ("discourse-level processing"; "DL"); deficiencies in either result in poor reading. FMRI has revealed consistent overlapping networks in word and passage reading, as well as unique regions for DL processing; however, less is known about how WL and DL processes interact. Here we examined functional connectivity from seed regions derived from where BOLD signal overlapped during word and passage reading in 38 adolescents ranging in reading ability, hypothesizing that even though certain regions support word- and higher-level language, connectivity patterns from overlapping regions would be task modulated. Results indeed revealed that the left-lateralized semantic and working memory (WM) seed regions showed task-dependent functional connectivity patterns: during DL processes, semantic and WM nodes all correlated with the left angular gyrus, a region implicated in semantic memory/coherence building. In contrast, during WL, these nodes coordinated with a traditional WL area (left occipitotemporal region). In addition, these WL and DL findings were modulated by decoding and comprehension abilities, respectively, with poorer abilities correlating with decreased connectivity. Findings indicate that key regions may uniquely contribute to multiple levels of reading; we speculate that these connectivity patterns may be especially salient for reading outcomes and intervention response.

Underperformance in math is a problem with increasing prevalence, complex etiology, and severe repercussions. This study examined the etiological heterogeneity of math performance in a sample of 264 pairs of 12-year-old twins assessed on measures of math achievement, numerosity, and math anxiety. Latent profile analysis indicated 5 groupings of individuals representing different patterns of math achievement, numerosity, and math anxiety, coupled with differing degrees of familial transmission. These results suggest that there may be distinct profiles of math achievement, numerosity, and anxiety, particularly for students who struggle in math.

Because recent initiatives highlight the need to better support preschool-aged children's math and science learning, the present study investigated the impact of professional development in these domains for early childhood educators. Sixty-five educators were randomly assigned to experience 10.5 days (64 hr) of training on math and science or on an alternative topic. Educators' provision of math and science learning opportunities were documented, as were the fall-to-spring math and science learning gains of children (n = 385) enrolled in their classrooms. Professional development significantly impacted provision of science, but not math, learning opportunities. Professional development did not directly impact children's math or science learning, although science learning was indirectly affected via the increase in science learning opportunities. Both math and science learning opportunities were positively associated with children's learning. Results suggest that substantive efforts are necessary to ensure that children have opportunities to learn math and science from a young age.

The current study examined the association between frequency of storybook reading and emergent literacy in 212 children at risk for language impairment, assessed during the fall semester of kindergarten. Measures included parent-reported storybook reading, as well as direct assessments of print knowledge, letter awareness, and expressive vocabulary. Results suggested nonsignificant to moderate (r = 0.11 to 0.25) correlations between frequency of storybook reading and child emergent literacy across the entire range of environment and ability. Quantile regression results suggested that the association was highest at low frequency of storybook reading, particularly for print knowledge, approaching r = 0.50. Moreover, the association between frequency of storybook reading and emergent literacy was highest at higher levels of emergent literacy for print knowledge, but particularly for letter naming, approaching r = 0.80. These results suggest that in children with language difficulties, the relationship between aspects of the home environment and emergent literacy is conditional on the quality of the home environment as well as the child's proficiency in emergent literacy skills.

To contribute to the modest body of work examining the home literacy environment (HLE) and emergent literacy outcomes for children with disabilities, this study addressed two aims: (a) to determine the unique contributions of the HLE on print knowledge of preschool children with language impairment and (b) to identify whether specific child characteristics (oral language ability, print interest) moderated these relations. The sample consisted of 119 preschool children with language impairment. HLE was conceptualised as frequency of storybook reading and literacy teaching during book reading. Frequency of storybook reading was a unique predictor of print knowledge, which is consistent with research on children with typical language. Literacy teaching did not predict print knowledge, which diverges from research on children with typical language. No interactions between the HLE and child characteristics were significant, but language ability and print interest play a role in understanding individual differences in literacy development.

Background: Numerous studies have examined gene × environment interactions (G × E) in cognitive and behavioral domains. However, these studies have been limited in that they have not been able to directly assess differential patterns of gene expression in the human brain. Here, we assessed G × E interactions using two publically available datasets to assess if DNA variation is associated with post-mortem brain gene expression changes based on smoking behavior, a biobehavioral construct that is part of a complex system of genetic and environmental influences. Methods: We conducted an expression quantitative trait locus (eQTL) study on two independent human brain gene expression datasets assessing G × E for selected psychiatric genes and smoking status. We employed linear regression to model the significance of the Gene × Smoking interaction term, followed by meta-analysis across datasets. Results: Overall, we observed that the effect of DNA variation on gene expression is moderated by smoking status. Expression of 16 genes was significantly associated with single nucleotide polymorphisms that demonstrated G × E effects. The strongest finding (p = 1.9 × 10[superscript -11]) was neurexin 3-alpha ("NRXN3"), a synaptic cell-cell adhesion molecule involved in maintenance of neural connections (such as the maintenance of smoking behavior). Other significant G × E associations include four glutamate genes. Conclusions: This is one of the first studies to demonstrate G × E effects within the human brain. In particular, this study implicated "NRXN3" in the maintenance of smoking. The effect of smoking on "NRXN3" expression and downstream behavior is different based upon SNP genotype, indicating that DNA profiles based on SNPs could be useful in understanding the effects of smoking behaviors. These results suggest that better measurement of psychiatric conditions, and the environment in post-mortem brain studies may yield an important avenue for understanding the biological mechanisms of G × E interactions in psychiatry.

Background: Attention-deficit/hyperactivity disorder (ADHD) symptoms and mathematics ability are associated, but little is known about the genetic and environmental influences underlying this association. Methods: Data came from more than 6,000 twelve-year-old twin pairs from the UK population-representative Twins Early Development Study. Parents rated each twin's behaviour using a DSM-IV-based 18-item questionnaire of inattentive and hyperactive-impulsive ADHD symptoms. Mathematics tests based on the UK National Curriculum were completed by each twin. The twins also completed standardised tests of reading and general cognitive ability. Multivariate twin model fitting was applied. Results: Inattentive and hyperactive-impulsive ADHD symptoms were highly heritable (67% and 73% respectively). Mathematics ability was moderately heritable (46%). Mathematics ability and inattentiveness showed a significantly greater phenotypic correlation (r[subscript p] = -0.26) and genetic correlation (r[subscript A] = -0.41) than mathematics ability and hyperactivity-impulsivity (r[subscript p] = -0.18; r[subscript A] = -0.22). The genetic correlation between inattentiveness and mathematics ability was largely independent from hyperactivity-impulsivity, and was only partially accounted for by genetic influences related to reading and general cognitive ability. Conclusions: Results revealed the novel finding that mathematics ability shows significantly stronger phenotypic and genetic associations with inattentiveness than with hyperactivity-impulsivity. Genetic associations between inattentiveness and mathematics ability could only partially be accounted for by hyperactivity-impulsivity, reading and general cognitive ability. Results suggest that mathematics ability is associated with ADHD symptoms largely because it shares genetic risk factors with inattentiveness, and provide further evidence for considering inattentiveness and hyperactivity-impulsivity separately. DNA markers for ADHD symptoms (especially inattentiveness) may also be candidate risk factors for mathematics ability and vice versa.

Reading disability (RD) and math disability (MD) frequently co-occur, but the etiology of this comorbidity is not well understood. Groups with RD only (N = 241), MD only (N = 183), and RD + MD (N = 188) and a control group with neither disorder (N = 411) completed a battery of measures of internalizing and externalizing psychopathology, social and academic functioning, and 10 neuropsychological processes. Groups with RD only, MD only, and RD + MD were significantly impaired versus the control group on nearly all measures, and the group with RD + MD was more impaired than the groups with MD and RD alone on measures of internalizing psychopathology, academic functioning, and 7 of 10 neuropsychological constructs. Multiple regression analyses of the neuropsychological measures indicated that deficits in reading and math were associated with shared weaknesses in working memory, processing speed, and verbal comprehension. In contrast, reading difficulties were uniquely associated with weaknesses in phoneme awareness and naming speed, and math deficits were uniquely associated with weaknesses in set shifting. These results support multiple-deficit neuropsychological models of RD and MD and suggest that RD and MD are distinct but related disorders that co-occur because of shared neuropsychological weaknesses in working memory, processing speed, and verbal comprehension.

Purpose: We evaluated genetic and environmental contributions to individual differences in language skills during early adolescence, measured by both language sampling and standardized tests, and examined the extent to which these genetic and environmental effects are stable across time. Method: We used structural equation modeling on latent factors to estimate additive genetic, shared environmental, and nonshared environmental effects on variance in standardized language skills (i.e., Formal Language) and productive language-sample measures (i.e., Productive Language) in a sample of 527 twins across 3 time points (mean ages 10-12 years). Results: Individual differences in the Formal Language factor were influenced primarily by genetic factors at each age, whereas individual differences in the Productive Language factor were primarily due to nonshared environmental influences. For the Formal Language factor, the stability of genetic effects was high across all 3 time points. For the Productive Language factor, nonshared environmental effects showed low but statistically significant stability across adjacent time points. Conclusions: The etiology of language outcomes may differ substantially depending on assessment context. In addition, the potential mechanisms for nonshared environmental influences on language development warrant further investigation., In the child-language literature, adolescent development often gets overshadowed by the exciting linguistic milestones of the earlier years. Nevertheless, it is difficult to imagine a more significant transitional period than [...]

Although evidence suggests that individual differences in reading and mathematics skills are correlated, this relationship has typically only been studied in relation to word decoding or global measures of reading. It is unclear whether mathematics is differentially related to word decoding and reading comprehension. In the current study, the authors examined these relationships at both a phenotypic and an etiological level in a population-based cohort of 5,162 twin pairs at age 12 years. Multivariate genetic analyses of latent phenotypic factors of mathematics, word decoding, and reading comprehension revealed substantial genetic and shared environmental correlations among all three domains. However, the phenotypic and genetic correlations between mathematics and reading comprehension were significantly greater than those between mathematics and word decoding. Independent of mathematics, there was also evidence for genetic and nonshared environmental links between word decoding and reading comprehension. These findings indicate that word decoding and reading comprehension have partly distinct relationships with mathematics in the middle school years. (Contains 6 tables and 2 figures.)

Purpose: The authors examined the longitudinal stability of genetic and environmental influences on children's productive language sample measures during the early school-age years. Method: Twin study methodology with structural equation modeling was used to derive univariate estimates of additive genetic (A), shared environmental (C), and nonshared environmental (E) effects on language measures at each of 2 time points, based on 487 twins at the 1st-grade time point and 387 twins at the 2nd-grade time point. To address questions of stability over time, the authors used longitudinal latent factor analysis. Results: Stability in the Conversational Language factor was accounted for almost entirely by shared genetic effects between 1st and 2nd grade, meaning no new genetic effects were observed at the 2nd time point. In contrast, nonshared environmental effects were entirely time point specific, meaning whatever nonshared environmental influences were operating at the first time point were not influencing individual variation in the language factor at the second time point. Conclusion: The discussion in this article centers on possible candidates for both genetic and nonshared environmental effects as well as implications for clinical practice and future research.

The authors examined whether math fluency was independent from untimed math and from reading using 314 pairs of school-aged twins drawn from the Western Reserve Reading and Math Projects. Twins were assessed through a 90-min home visit at approximately age 10 and were reassessed in their homes approximately 1 year later. Results suggested that the shared environment and genetics influenced the covariance among math fluency, untimed math measures, and reading measures. However, roughly two thirds of the variance in math fluency was independent from untimed math measures and reading, including reading fluency. The majority of this independent variance was the result of genetic factors that were longitudinally stable across two measurement occasions. These results suggest that math fluency, although related to other math measures, may also be a genetically distinct dimension of mathematics performance. (Contains 4 tables and 3 figures.)

The present research examines whether children's daily attendance rates would be predictive of gains in expressive language within the context of high-quality preschool classrooms. The quality of preschool classrooms was assessed by measuring the quality of the teacher's interactions with the children in his or her classroom. Hierarchical linear models, nesting children within classroom, were used to examine children's growth in expressive language in two independent samples (n = 129 children in 14 classrooms; n = 160 children in 46 classrooms). Results showed positive relations between daily attendance and language gains for children enrolled in higher quality preschool classrooms. Findings suggest that at-risk children who are rarely absent from high-quality preschool classrooms show accelerated expressive language growth, thus indicating that preschool attendance is an important factor to consider in future research and policy decisions.