Early language and executive skills predict variations in number and arithmetic skills in children at family-risk of dyslexia and typically developing controls

Child Vocabulary and Developmental Growth in Executive Functions During Toddlerhood

Executive functions (EFs) emerge in the first years of life and are essential for many areas of child development. However, intraindividual developmental trajectories of EF during toddlerhood and their associations with ongoing development of language skills remain poorly understood. The present three-wave study examined these trajectories and their associations with language skills. Child EF and vocabulary were assessed around 13, 19, and 28 months of age in a sample of 145 toddlers (51% boys) from mostly White families. At each time point, mothers reported on child receptive and expressive vocabulary, and EF were assessed with three behavioral tasks targeting inhibitory control, cognitive flexibility, and working memory. Multilevel growth models revealed that toddlerhood is a period of significant developmental growth in child inhibitory control, cognitive flexibility, and working memory. The findings also provide evidence for a sustained relation between toddlers' language skills and their ongoing acquisition of inhibitory control and cognitive flexibility. This study offers novel insight into intraindividual developmental changes in EF during toddlerhood and the role of language in these meaningful, though neglected, changes.

The interconnection of orthographic, phonetic, and semantic skills with arithmetic fluency

Arithmetic fluency is considered considers highly rely on language processing, encompassing essential skills. However, the independent predictive power of phonetic, semantic, or orthographic skills in relation to arithmetic fluency remains an unresolved query. This study introduces the common component hypothesis to elucidate the inconsistent findings in previous research. The hypothesis posits that significant correlations between language and mathematics hinge on whether the language and mathematics utilized in a given task share a common component. According to this hypothesis, processing skills for each of the three fundamental language elements (i.e., phonetic, semantic, orthographic) should correlate with arithmetic fluency, as these elements are also integral to simple arithmetic processing. A cohort of one hundred and ninety-eight primary school students participated in the study, undertaking a battery of tests assessing general cognitive abilities, psycholinguistic elements, and arithmetic fluency. The results showed that orthographic, phonetic, and semantic abilities independently predicted arithmetic fluency, even after accounting for all other cognitive predictors. These findings substantiate the common component hypothesis, providing empirical support for explaining the association between language and mathematics. This evidence contributes to addressing the interplay between language and mathematics in educational contexts.

The relationship between family socioeconomic status and the young children's number sense development: The mediating role of parent-child activities

This study examines the relationship between family socioeconomic status, parent-child activities, and young children's digital development. Using the Family SES questionnaire, the parent-child activities questionnaire, and the 5 to 6 year old children's number sense development scale as research instruments, 314 young children (M = 70.42, SD = 3.47). The results show that: (1) Family Socioeconomic Status can significantly positively predict the young children's number sense development; (2) Parent-child activities play a partial mediating role in the relationship between family socioeconomic status and the young children's number sense development. This study provides specific guidelines and recommendations for improving the young children's number sense development.

From terrible twos to sassy sixes: The development of vocabulary and executive functioning across early childhood

Across the early childhood period of development, young children exhibit considerable growth in their executive functioning (EF) and vocabulary abilities. Understanding the developmental trajectory of these seemingly interrelated processes is important as both early vocabulary and EF have been shown to predict critical academic and socio-emotional outcomes later in childhood. Although previous research suggests that EF and vocabulary are correlated in early childhood, much of the existing longitudinal research has focused on unidirectional relations among preschool child samples. The current large-scale study, therefore, sought to examine whether children's vocabulary and EF abilities are bidirectionally related over time across four measurement waves in early childhood (i.e., at ages 2, 3, 4, and 6). At each timepoint, children's vocabulary skills were positively correlated with their concurrent EF abilities. After controlling for child sex and maternal education status, the best-fitting, cross-lagged panel model was a unidirectional model whereby children's early vocabulary scores predicted their later EF performance at each timepoint. Although age 2 EF significantly predicted age 3 vocabulary size, this association was no longer significant after accounting for maternal education status. Our results illustrate that vocabulary size plays an important role in predicting children's later EF performance across various timepoints in early childhood, even after controlling for children's initial EF scores. These findings have important implications for intervention research as fostering early vocabulary acquisition may serve as a possible avenue for improving EF outcomes in young children. RESEARCH HIGHLIGHTS: Children's vocabulary size is positively correlated with their concurrent executive functioning skill at ages 2, 3, 4, and 6 Young children's early vocabulary scores predict their later EF performance across measurement waves, even after controlling for initial EF skill There is stability in children's relative vocabulary size and executive functioning performance over time in early childhood.

The Longitudinal Contributions of Preschool Executive Functions and Early Math Abilities to Arithmetic Skills in Elementary School

Executive functions (EFs) are linked to children's overall math performance, although few studies have considered the joint role of prior math abilities for specific math subskills, such as arithmetic. The current study examined the longitudinal contributions of preschool EFs and early math abilities to children's accuracy and reaction time on arithmetic problems. Two hundred and eighty-three children completed EF and numeracy assessments at 5.25 years old. Children completed an arithmetic problem task in first (Mage = 7.14), second (Mage = 8.09), and third grade (Mage = 9.08). Results indicated that preschool EFs and math abilities are uniquely linked to children's accuracy and reaction time at age 7, whereas preschool EFs alone continue to predict accuracy at age 8 and reaction time at age 9, even after accounting for intervening arithmetic performance. The study highlights the sustained, unique importance of early EFs for children's arithmetic acquisition.

Cognitive Profiles of Children with Isolated and Comorbid Learning Difficulties in Reading and Math: a Meta-analysis

The causes underlying comorbid learning difficulties in reading (RD) and math (MD) are still a matter of debate. Based on current research, two models for the relation of the cognitive profile of isolated and combined learning difficulties (RDMD) are discussed. Regarding the “multi-deficit model”, the profile of RDMD is characterized by the sum of domain-specific core deficits of RD and MD (additivity) as well as shared domain-general risk factors of RD and MD resulting in less severe deficits than expected under additivity (under-additivity). The “three independent disorders model” explains RDMD as a distinct learning disorder, showing a separate cognitive profile with distinct and/or more severe deficits, compared to the sum of RD’s and MD’s profiles (over-additivity). To evaluate these approaches, a meta-analysis including 74 studies, examining children aged 6–12, was conducted. Separate group comparisons for the three subcomponents in the cognitive profiles—reading, math, executive functions (EF)—were considered. Linear hypothesis testing revealed different results regarding the three subcomponents of the cognitive profiles of children with isolated vs. combined learning difficulties: Whereas RDMDs’ deficits in reading and math represented the sum of the deficits in the isolated groups (additivity), there was some evidence that RDMDs’ deficits in EF skills corresponded to under-additivity. Furthermore, group differences in math skills were more pronounced in symbolic than in non-symbolic math tasks, whereas in reading, group differences were larger in phonological processing and reading than in rapid automatized naming and language skills. Results are discussed in terms of intervention options for RDMD.

Vocabulary and Executive Functioning: A Scoping Review of the Unidirectional and Bidirectional Associations across Early Childhood

Early childhood marks a time where word learning is accompanied by rapid growth in the cognitive processes that underlie self-modulated and goal-directed behavior (i.e., executive functions). Although there is empirical evidence to support the association between executive functioning and vocabulary in childhood, inconsistent findings have been reported regarding the extent to which early executive functioning abilities predict later vocabulary outcomes and vice versa. To clarify the nature of the longitudinal relation between these two processes and to examine what, if any, claims can be made about their interdependence, a critical review of the literature was conducted. Also addressed are the conceptual and/or methodological differences that exist across studies conducted on this topic that may be contributing to some of the discrepancies reported in the longitudinal literature. Finally, this review provides practical and empirically informed future directions to serve as a resource for early childhood researchers advancing this area of study.

How bilingualism modulates selective attention in children

There is substantial evidence that learning and using multiple languages modulates selective attention in children. The current study investigated the mechanisms that drive this modification. Specifically, we asked whether the need for constant management of competing languages in bilinguals increases attentional capacity, or draws on the available resources such that they need to be economised to support optimal task performance. Monolingual and bilingual children aged 7–12 attended to a narrative presented in one ear, while ignoring different types of interference in the other ear. We used EEG to capture the neural encoding of attended and unattended speech envelopes, and assess how well they can be reconstructed from the responses of the neuronal populations that encode them. Despite equivalent behavioral performance, monolingual and bilingual children encoded attended speech differently, with the pattern of encoding across conditions in bilinguals suggesting a redistribution of the available attentional capacity, rather than its enhancement.

A Systematic Review and Meta-Analysis of the Language Skills of Youth Offenders

PURPOSE

This systematic review and meta-analysis estimates the overall language skills of youth offenders involved with the juvenile justice system. Given the importance of this population, identifying avenues through which we can increase the likelihood of successful interventions is a necessary societal effort.

METHOD

Eighteen studies, representing data from 3,304 individuals, contributed 82 effect sizes to the current analytic sample. We used random-effects models to estimate the overall mean effect size metric to address each research question and fit meta-regression models for each moderator analysis.

RESULTS

Results yielded that youth offenders presented with significantly lower language skills than their nonoffending peers (g = -1.26). Furthermore, high proportions of the present meta-analytic sample were classified as youth with moderate (50%) and severe (10%) language disorders. In general, differences in language skills did not vary as a function of age, gender, or language measure type. We did detect significant differences as a function of sample country and type of peer comparison group.

CONCLUSIONS

This meta-analysis reports on the significantly compromised language skills of youth offenders. We conclude with a discussion of the findings and consideration of the implications for research and practice.

Tracking Familial History of Reading and Math Difficulties in Children's Academic Outcomes

The current study aimed to investigate the extent to which familial history of reading and math difficulties have an impact on children's academic outcomes within a 3-year longitudinal study, which evaluated their core reading and math skills after first (N = 198; 53% girls) and second grades (N = 166), as well as performance on complex academic tasks after second and third grades (N = 148). At baseline, parents were asked to complete the Adult Reading History Questionnaire (ARHQ) and its adaption, Adult Math History Questionnaire (AMHQ), to index familial history of reading and math difficulties, respectively. Preliminary findings established the psychometric properties of the AMHQ, suggesting that it is a reliable and valid scale. Correlation analyses indicated that the ARHQ was negatively associated with children's reading skills, whereas the AMHQ was negatively related to math outcomes. Path results revealed that the ARHQ predicted children's performance on complex reading tasks indirectly via their core reading skills, and the AMHQ was linked to complex math outcomes indirectly via core math abilities. The ARHQ was also found to be negatively correlated with measures of children's math performance, with path findings suggesting that these relations were indirectly explained by differences in their core reading skills. These results suggest that assessing familial risk for academic difficulties may be crucial to understanding comorbid etiological and developmental associations between reading and math differences.

Home activities and cognitive skills in relation to early literacy and numeracy: testing a multifactorial model in preschoolers

The aim of the present study was to test environmental and cognitive variables as possible cross-domain predictors of early literacy and numeracy skills. One hundred forty-eight preschool children (mean age = 64.36 months ± 3.33) were enrolled in the study. The battery included a home literacy and home numeracy questionnaire, measures and phonological and visuo-spatial working memory, tasks tapping response inhibition, and predictors of literacy (vocabulary, phonological awareness, letter knowledge) and numeracy (magnitude comparison, number knowledge) skills. The structural equation model indicated that verbal working memory and, to a lesser extent, inhibition represented cross-domain predictors, whereas home numeracy activities and visuo-spatial working memory explained additional variance only for early numeracy skills. Implications for parents and educators are discussed.

Behaviors Interfering with Audiometry Associated with Eventual Diagnosis of Autism

Children referred for audiology evaluation due to speech and language delays represent a neurodevelopmentally high-risk group. The audiology evaluation is a behaviorally-challenging encounter early in the diagnostic process. We assessed interfering behaviors (IB) that complicated completion of audiometry as predictors of autism spectrum disorder (ASD) diagnosis. This retrospective cohort study using the Military Health System electronic medical record included 296 children aged 18 to 71 months. Children who displayed IB had increased odds of receiving an ASD diagnosis compared to those who did not (OR = 5.6, 95% CI 2.6-12.1). Interfering behaviors had a high specificity (81%) and negative predictive value (94%) for ASD. The audiology evaluation may represent an opportunity early in the diagnostic process to stratify risk for ASD.

Arithmetic in developmental cognitive disabilities

This paper reviews and discusses research on arithmetical strengths and weaknesses in children with specific developmental cognitive disabilities. It focusses on children with dyslexia, developmental language disorder, attention deficit hyperactivity disorder and autism. In general, studies show that arithmetical weaknesses are commoner in children with any of these disorders than in controls. Autism is sometimes associated with specific strengths in arithmetic; but even in autism, it is commoner for arithmetic to be a relative weakness than a relative strength. There may be some genetic reasons why there is an overlap between mathematical difficulties and other developmental learning difficulties; but much of the reason seems to be that specific aspects of arithmetic are often influenced by other factors, including language comprehension, phonological awareness, verbal and spatial working memory and long-term memory, and executive functions. The findings discussed here will be discussed in relation to Pennington's (2006) Multiple Deficit Model.

Language difficulties are a shared risk factor for both reading disorder and mathematics disorder

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Disorders of language (DLD), reading (RD) and mathematics (MD) are highly comorbid.

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RD and MD is associated with familial dyslexia and preschool language difficulties.

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The comorbidity between RD and MD arises because of shared risk factors.

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Children with RD should be assessed for MD and vice versa.

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Interventions for MD should take account of likely language problems.

Disorders of reading and mathematics co-occur at greater than chance rates, but they are often studied separately. This article reports the reading and arithmetic outcomes at 9 years of age from a longitudinal study of 224 children at high risk for dyslexia. Using a cutoff at the 10th centile, groups of children with reading disorder (RD), mathematics disorder (MD), and comorbid reading disorder and math disorder (RD&MD) were identified. The risk of these disorders was elevated in children selected in preschool with language difficulties or at family risk for dyslexia. There was a high degree of comorbidity between RD and MD, and many cases—particularly in the comorbid group—also reached the diagnostic threshold for developmental language disorder (DLD). On measures of language, phoneme awareness, rapid automatized naming (RAN) digits, and rated inattention, there was a stepwise pattern: RD > MD > RD&MD. Poor language was associated with each disorder and appears to be a cognitive risk factor for RD, MD, and RD&MD. These findings suggest that there are shared genetic risk factors operating for both RD and MD.

Longitudinal Effects of the Home Learning Environment and Parental Difficulties on Reading and Math Development Across Grades 1-9

This study focuses on parental reading and mathematical difficulties, the home literacy environment, and the home numeracy environment as well as their predictive role in Finnish children’s reading and mathematical development through Grades 1–9. We examined if parental reading and mathematical difficulties directly predict children’s academic performance and/or if they are mediated by the home learning environment. Mothers (n = 1590) and fathers (n = 1507) reported on their reading and mathematical difficulties as well as on the home environment (shared reading, teaching literacy, and numeracy) when their children were in kindergarten. Tests for reading fluency, reading comprehension, and arithmetic fluency were administered to children in Grades 1, 2, 3, 4, 7, and 9. Parental reading difficulties predicted children’s reading fluency, whereas parental mathematical difficulties predicted their reading comprehension and arithmetic fluency. Familial risk was associated with neither formal nor informal home environment factors, whereas maternal education had a significant relationship with both, with higher levels of education among mothers predicting less time spent on teaching activities and more time spent on shared reading. In addition, shared reading was significantly associated with the development of reading comprehension up to Grades 3 and 4, whereas other components of the home learning environment were not associated with any assessed skills. Our study highlights that taken together, familial risk, parental education, and the home learning environment form a complex pattern of associations with children’s mathematical and reading skills.

A latent growth curve analysis of precursor cognitive abilities and academic achievement

BACKGROUND

Language-based cognitive fitness describes the ability to carry out cognitive tasks with vigour and alertness, to learn, and to adapt.

AIMS

The purpose of this research was to test the efficacy of a brain fitness training programme to better understand the role played by three precursor abilities for language-based cognitive development-verbal reasoning, visual synthesis, and active analysis-and their impact on academic achievement.

SAMPLE

The sample included 92 children from a private school designed to deliver a prescriptive educational model for the spectrum of challenged, average, and gifted students.

METHOD

Students completed cognitive tests at entry to the program and at the end of each academic year. Students completed daily brain-based exercises. Associative latent variable growth curve modelling using Mplus was used to test growth in all variables. Bayesian estimation analysis was used for missing data imputation. Age and baseline cognitive ability were included as covariates.

RESULTS

Model fit was excellent, χ² (104) = 115.98, p = .20, (χ² /df) = 1.11, CFI = 0.98, TLI = 0.98, RMSEA = 0.04, SRMR = 0.05. Students who started with the lowest ability levels initially grew faster than those students with higher initial two-wave performance levels consistent with a closing of an ability gap. This had a lagged effect on achievement that accelerated in growth after the first 2 years.

CONCLUSIONS

Results provide evidence for the importance of interventions that focus on strengthening precursor cognitive abilities directly involved with language and mathematics achievement.

Understanding comorbidity of learning disorders: task-dependent estimates of prevalence

BACKGROUND

Reading disorder (RD) and mathematics disorder (MD) frequently co-occur. However, the exact comorbidity rates differ largely between studies. Given that MD is characterised by high heterogeneity on the symptom level, differences in comorbidity rates may result from different mathematical subskills used to define MD. Comorbidity rates with RD are likely to be higher when MD is measured by mathematical subskills that do not only build on number processing, but also require language (i.e. arithmetic fluency), than when measured by magnitude processing skills.

METHODS

The association between literacy, arithmetic fluency and magnitude processing as well as the overlap between deficits in these domains were assessed in a representative sample of 1,454 third Graders.

RESULTS

Associations were significantly higher between literacy and arithmetic, than between literacy and magnitude processing. This was also reflected in comorbidity rates: comorbidity rates between literacy and arithmetic deficits were four times higher than expected by chance, whereas comorbidity rates between literacy and magnitude processing deficits did not exceed chance rate. Deficits in the two mathematical subskills showed some overlap, but also revealed dissociations, corroborating the high heterogeneity of MD. Results are interpreted within a multiple-deficit framework and implications for diagnosis and intervention are discussed.

CONCLUSIONS

The overlap between RD and MD depends on the subskills used to define MD. Due to shared domain-general factors mathematical subskills that draw on language skills are more strongly associated with literacy than those that do not require language. The findings further indicate that the same symptom, such as deficits in arithmetic, can be associated with different cognitive deficits, a deficit in language skills or a deficit in number processing.

The integration of symbolic and non-symbolic representations of exact quantity in preschool children

Preschoolers (n=62) completed tasks that tapped their knowledge of symbolic and non-symbolic exact quantities, their ability to translate among different representations of exact quantity (i.e., digits, number words, and non-symbolic quantities), and their non-symbolic, digit, and spoken number comparison skills (e.g., which is larger, 2 or 4?). As hypothesized, children's knowledge about non-symbolic exact quantities, spoken number words, and digits predicted their ability to map between symbolic and non-symbolic exact quantities. Further, their knowledge of the mappings between digits and non-symbolic quantities predicted symbolic number comparison (i.e., of spoken number words or written digits). Mappings between written digits and non-symbolic exact quantities developed later than the other mappings. These results support a model of early number knowledge in which integration across symbolic and non-symbolic representations of exact quantity underlies the development of children's number comparison skills.

Developmental Dyscalculia

Developmental dyscalculia (DD) is a specific learning disorder that affects the acquisition of arithmetic skills and number processing in children. A high comorbidity between DD and other neurodevelopmental disorders (e.g., dyslexia, attention-deficit/hyperactivity disorder [ADHD]) as well as substantial heterogeneity in cognitive profiles have been reported. Current studies indicate that DD is persistent, has a genetic component, and is related to functional and structural alterations of brain areas involved in magnitude representation. Recent neuronal and behavioral evidence is presented, showing that DD entails (a) impairments in two preverbal core systems of number, an approximate system for estimating larger magnitudes and an exact system for representing small magnitudes, (b) deficits in symbolic number processing, (c) aberrant and nonadaptive neuronal activation in basic magnitude processing and calculation, (d) dysfunctional arithmetic fact retrieval and persistent use of counting strategies in calculation, and (e) deficits in visuospatial working memory and the central executive. Finally, open research questions, including the role of domain-general cognitive resources in DD, causes and developmental consequences of comorbidity, as well as design and evaluation of interventions for DD, are briefly discussed.