Are 22q11.2 distal deletions associated with math difficulties?

Approximately 6% of school-aged children have math difficulties (MD). A neurogenetic etiology has been suggested due to the presence of MD in some genetic syndromes such as 22q11.2DS. However, the contribution of 22q11.2DS to the MD phenotype has not yet been investigated. This is the first population-based study measuring the frequency of 22q11.2DS among school children with MD. Children (1,564) were identified in the schools through a screening test for language and math. Of these children, 152 (82 with MD and 70 controls) were selected for intelligence, general neuropsychological, and math cognitive assessments and for 22q11.2 microdeletion screening using MLPA. One child in the MD group had a 22q11.2 deletion spanning the LCR22-4 to LCR22-5 interval. This child was an 11-year-old girl with subtle anomalies, normal intelligence, MD attributable to number sense deficit, and difficulties in social interactions. Only 19 patients have been reported with this deletion. Upon reviewing these reports, we were able to characterize a new syndrome, 22q11.2 DS (LCR22-4 to LCR22-5), characterized by prematurity; pre- and postnatal growth restriction; apparent hypotelorism, short/upslanting palpebral fissures; hypoplastic nasal alae; pointed chin and nose; posteriorly rotated ears; congenital heart defects; skeletal abnormalities; developmental delay, particularly compromising the speech; learning disability (including MD, in one child); intellectual disability; and behavioral problems. These results suggest that 22q11.2 DS (LCR22-4 to LCR22-5) may be one of the genetic causes of MD.

Theoretical-Methodological Foundations for the Global Integration Method (Método de Integração Global-MIG) in the Treatment of Autism Spectrum Disorder.

Currently, there is no intervention model for autism spectrum disorder (ASD) that addresses all levels and factors of the International Classification of Functioning, Disability and Health (ICF, WHO). The most researched programs focus on naturalistic, developmental and behavioral approaches to socio-communication. Less attention has been paid to motor and environmental reactivity aspects (behavior/interest restriction and sensory reactivity). The evidence rationale for the Global Integration Method (MIG, "Método de Integração Global"), a model addressing sensorimotor reactivity in addition to socio-communication, is presented. MIG is an integrative, interdisciplinary, family-oriented intervention and naturalistic program that addresses all levels and moderating factors of ASD's impact. MIG's theoretical rationale is based on the predictive coding impairment and embodied cognition hypotheses. MIG incorporates both bottom-up (flexible therapeutic suit, social-motor synchronization) and top-down (schematic social information processing, narratives, imagery) strategies to promote the building and use of accurate, flexible and context-sensitive internal predictive models. MIG is based on the premises that predictive coding improves both socio-communication and environmental reactivity, and that the postural stabilization provided by the flexible therapeutic suit frees information processing resources for socio-cognitive learning. MIG builds on interdisciplinary, professionally and parentally mediated work based on behavioral principles of intensive training in a situated environment.

Transcoding abilities in typical and atypical mathematics achievers: the role of working memory and procedural and lexical competencies.

Transcoding between numerical systems is one of the most basic abilities acquired by children during their early school years. One important topic that requires further exploration is how mathematics proficiency can affect number transcoding. The aim of the current study was to investigate transcoding abilities (i.e., reading Arabic numerals and writing dictation) in Brazilian children with and without mathematics difficulties, focusing on different school grades. We observed that children with learning difficulties in mathematics demonstrated lower achievement in number transcoding in both early and middle elementary school. In early elementary school, difficulties were observed in both the basic numerical lexicon and the management of numerical syntax. In middle elementary school, difficulties appeared mainly in the transcoding of more complex numbers. An error analysis revealed that the children with mathematics difficulties struggled mainly with the acquisition of transcoding rules. Although we confirmed the previous evidence on the impact of working memory capacity on number transcoding, we found that it did not fully account for the observed group differences. The results are discussed in the context of a maturational lag in number transcoding ability in children with mathematics difficulties.

The neural correlates of interference effects of numerical Stroop task: An ALE meta-analysis and connectometry.

Numerical skills are part of cognitive and formal education development, and low performance in math has been associated with adverse features such as low income and unemployment. The studies of functional magnetic resonance imaging (fMRI) activation in numerical Stroop interference had been accomplished to evidence neural correlates of numerical, automatic, and controlled processes. The aim of this research was to summarize the results of the neural correlates of a number-size congruity task through meta-analysis of fMRI, behavioral evidence, and connectometry. Our study includes 15 fMRI papers (total number of subjects n=155-302, the total number of foci=81-233). Meta-analyses used an activation likelihood estimation (ALE) logarithm. For connectometry, it was used the diffusion tensor image. We found that, for the attentional control numerical Stroop effect, the activated areas were the dorsolateral prefrontal cortex, the anterior cingulate gyrus, and the intraparietal sulcus. Consistent activation over both paradigms was found in five clusters, two in the frontal and three in the parietal lobe. The matrix of connectivity showed connections between insula and inferior parietal right with 587 fibers, cingulate gyrus, and inferior parietal right with 843 fibers. Both paradigms activate parietal areas but differ in the activation of regions correlated to attentional control. The results of these meta-analyses summarized results from fMRI studies that may contribute to current theories. The results of connectometry could be interpreted regarding the fibers connection between the clusters right inferior parietal with insula and cingulate gyrus that suggests the integration of information.

Neuromotor examination in unilateral cerebral palsy: Bilateral impairments in different levels of motor integration.

Unilateral cerebral palsy (UCP) usually results in damage to the unilateral pyramidal system. However, the clinical presentation of neuromotor deficits also suggests lesions to the extrapyramidal and cerebellar systems bilaterally. In this study, we developed and tested a behavioral neuromotor examination protocol assessing impairments at three levels of motor integration for children with UCP, also considering impairments of the non-paretic upper limb as well as the influences of the laterality of the lesion. We included 30 children with UCP (10.79 ± 2.61 years) and 60 healthy children (8.27 ± 1.57 years) in the study. All children were assessed on general cognitive ability and classified according to the manual ability classification system (MACS). Our neuromotor examination protocol incorporated specific tasks for each level of motor integration: pyramidal, extrapyramidal and cerebellar. Children with UCP and controls did not differ with respect to general cognitive abilities and sex but children with UCP were significantly older. Controls performed significantly better than children with UCP on neuromotor tasks at all levels of motor integration. Additionally, performance of the non-plegine hand in children with UCP was significantly inferior to controls. With the exception of fine motor skills (pyramidal level), children with right and left UCP did not differ. Our behavioral neuromotor examination was sensitive to reveal impairments at all three levels of motor integration bilaterally in children with UCP-although more subtle for the non-paretic limb.

Body experience influences lexical-semantic knowledge of body parts in children with hemiplegic cerebral palsy.

Background: Disorders in different levels of body representation (i.e., body schema, body structural description, and body image) are present in hemiplegic cerebral palsy (HCP). However, it remains unclear whether the body image develops from aspects of body schema and body structural description, and how this occurs in children with HCP. Objective and methods: In a cross-sectional study, we investigated 53 children with HCP (mean age about 10 years) and 204 typically developing (TD) control children to qualitatively evaluate whether and how body schema (related sensorimotor experiences) and body structural description (related visuospatial experiences) affect the development of children's body image and whether this development is delayed through HCP. Graph analysis was used to create a lexical-semantic map of body representation from data of a semantic word fluency task. Results: Results indicated a similar qualitative pattern of influences of sensorimotor and visuospatial experiences on lexical-semantic knowledge of body parts, with a delayed developmental course in children with HCP compared to TD children. Conclusion: These findings suggest that children's body image seemed to be influenced by body schema and body structural descriptions as indicated by poorer lexical-semantic knowledge of body parts in children with HCP due to missing physical experiences of the affected body parts. This might imply that "body talk" may beneficially complement physical therapy for children with HCP to promote body image development.

Working memory and arithmetic impairments in children with FMR1 premutation and gray zone alleles.

Expansive mutations in familial mental retardation 1 (FMR1) gene have been associated with different phenotypes. Full mutations are associated with intellectual disability and autism spectrum disorder; premutations are associated with math learning difficulties and working memory impairments. In gray zone, neuropsychological development has not yet been described. Objectives: This study aimed to describe the frequency of FMR1 premutation and gray zone alleles in a school population sample representing a broad spectrum of variation in math achievement and detail school achievement and cognitive performance in the children identified with FMR1 premutation or gray zone alleles. Methods: We described a two-phase study. In the first phase, 2,195 school-age children were screened for math achievement. In the second phase, 378 children with normal intelligence were neuropsychologically assessed and genotyped for FMR1. Of these, 121 children (61 girls) performed below percentile 25 in mathematics (MD group) and 257 children (146 girls) performed above percentile 25 (control group). Results: Four pupils presented expanded alleles, one premutation and three gray zone alleles. The girl with the premutation and one boy with a gray zone allele presented impairments in working memory and arithmetic performance below percentile 6, compatible with the diagnosis of developmental dyscalculia. These children's difficulties were not associated with inaccuracy of nonsymbolic number representations or literacy impairments. Dyscalculia in these children seems to be associated mainly with working memory impairments. Conclusions: FMR1 expansions in the gray zone may contribute to dyscalculia in otherwise healthy and normally intelligent children.

Mutações expansivas no gene FMR1 têm sido associadas a diferentes fenótipos. Mutações completas estão associadas a deficiência intelectual e transtorno do espectro do autismo; pré-mutações, com dificuldades de aprendizagem de matemática e comprometimentos de memória de trabalho. Na zona cinzenta o desenvolvimento neuropsicológico ainda não foi descrito. Objetivos: Descrever a frequência de alelos pré-mutados e zona cinzenta em uma amostra escolar que representa amplo espectro de variação do desempenho em Matemática e detalhar o desempenho escolar e cognitivo em crianças identificadas com alelos pré-mutados ou zona cinzenta. Métodos: Aqui, descrevemos um estudo de duas fases. Na primeira fase, 2.195 crianças em idade escolar foram selecionadas para desempenho em Matemática. Na segunda fase, 378 crianças com inteligência normal foram avaliadas neuropsicologicamente e, em seguida, por genotipagem FMR1. Resultados: Tiveram desempenho abaixo do percentil 25 em Matemática (grupo DM) 121 crianças (61 meninas), e tiveram desempenho acima do percentil 25 (grupo controle) 257 crianças (146 meninas). Quatro alunos apresentaram alelos expandidos, sendo uma pré-mutação e três alelos da zona cinza. A menina com a pré-mutação e um menino com o alelo da zona cinza apresentaram prejuízos na memória de trabalho e desempenho aritmético abaixo do percentil 6, compatíveis com o diagnóstico de discalculia do desenvolvimento. As dificuldades dessas crianças não foram associadas à imprecisão de representações não simbólicas de números ou deficiências de alfabetização. A discalculia nessas crianças parece estar associada principalmente a deficiências da memória de trabalho. Conclusões: Em conclusão, expansões na zona cinzenta do FMR1 podem contribuir para a discalculia em crianças saudáveis com inteligência normal.

Do boys with MAOA_LPR*2R allele present cognitive and learning impairments?

Monoamine oxidase A (MAOA) polymorphisms have been associated with antisocial disorders. Less attention has been paid to the cognitive functioning of individuals with different MAOA alleles. No study has described the cognitive phenotype associated with the less frequent, low enzyme activity allele, MAOA_LPR*2R. Objective: We describe the cognitive correlates of boys having MAOA_LPR*2R allele, ascertained in a sample of school children with normal intelligence, not referred for behavioral disorders. Methods: Participants were eight boys, attending from the second to fifth grades in state-run schools. They were identified among 712 children with typical general cognitive ability, genotyped for MAOA_LPR polymorphism. Participants were assessed with general intelligence, mathematics and spelling achievement, and verbal and visuospatial working memory tests. Neuropsychological performance was compared to published standards, using 1 SD below the mean as a cutoff value for low performance. Results: Intelligence of boys with MAOA_LPR*2R allele varied from above average (N=2) to low average in the other children. Five out of eight boys with the MAOA_LPR*2R allele had low mathematics achievement, and three presented additional difficulties with spelling. Four out of eight children had low short-term and working memory performance. Discussion: This is the first study describing cognitive correlates and school performance in boys having the MAOA_LPR*2R allele. Having this allele, and therefore, probably low MAO-A activity, does not necessarily imply low intelligence or low school performance. However, learning difficulties, particularly in math, and low working memory performance were observed in boys having this allele. This suggests a role of MAOA in learning difficulties.

Polimorfismos da monoaminoxidase A (MAOA) são associados a transtornos antissociais. Menos atenção tem sido dada ao funcionamento cognitivo de indivíduos com diferentes alelos de MAOA. Nenhum estudo descreveu o fenótipo cognitivo associado ao alelo menos frequente, de baixa atividade enzimática, MAOA_LPR*2R. Objetivo: Descrevemos os correlatos cognitivos de meninos com o alelo MAOA_LPR*2R, identificados em uma amostra de escolares com inteligência normal, não encaminhados por transtornos de comportamento. Métodos: Oito meninos com o alelo MAOA_LPR*2R foram identificados entre 712 crianças genotipadas, com inteligência típica, que cursavam do 2º ao 5º ano em escolas públicas. Foram avaliados: inteligência, desempenho em matemática e ortografia, memória de trabalho verbal e visuoespacial. O desempenho foi comparado a normas publicadas, utilizando-se 1 desvio padrão (DP) abaixo da média como ponto de corte para desempenho rebaixado. Resultados: A inteligência dos meninos com alelo MAOA_LPR*2R variou de acima da média (N=2) a médio-inferior nas demais crianças. Cinco dos oito meninos com alelo MAOA_LPR*2R apresentaram desempenho rebaixado em matemática e três apresentaram dificuldades adicionais em ortografia. Quatro dos oito meninos apresentaram baixo desempenho de memória de curto prazo e de trabalho. Discussão: Este é o primeiro estudo a descrever os correlatos cognitivos e o desempenho escolar em meninos com alelo MAOA_LPR*2R. Ter esse alelo não significa necessariamente baixa inteligência ou baixo desempenho escolar. No entanto, dificuldades de aprendizagem, principalmente em matemática, e desempenho rebaixado da memória de trabalho foram observados em mais da metade dos meninos com esse alelo. Isso sugere um papel do MAOA nas dificuldades de aprendizagem.

MAOA-LPR polymorphism and math anxiety: A marker of genetic susceptibility to social influences in girls?

Math anxiety (MA) seems to result from an interaction of genetic vulnerability with negative experiences learning mathematics. Although mathematics achievement does not substantially differ between the sexes, MA levels are usually higher in girls. Molecular genetic markers of MA vulnerability have been seldom explored. This article examines the contribution of the monoamine oxidase A gene (MAOA) to MA and to sex differences in MA. Five hundred and sixty-eight third to fifth graders were genotyped for the MAOA-LPR polymorphism (a repetitive element in MAOA promoter that has been associated with MAOA enzymatic activity), and assessed on general cognitive ability, mathematics achievement, and the cognitive and affective dimensions of MA. MAOA-LPR genotypes were classified as high (MAOA-H) or low (MAOA-L) according to their predicted enzymatic activity. Mixed models controlling for effects of school, sex, general cognitive ability, and mathematics achievement were evaluated. The best fitting model included school, math achievement, sex, MAOA-LPR, and the MAOA-LPR by sex interaction. This indicated that under the MAOA-H dominant model, anxiety toward mathematics interacted with the MAOA genotype: girls with an MAOA-L genotype exhibited higher levels of MA, with a small but significant effect. The association between MAOA-L genotype and MA in girls may represent an example of developmental plasticity.

Cognitive-behavioral intervention for math anxiety in childhood: a case report.

Math anxiety (MA) is a feeling of dread, tension and anxiety when dealing with math situations. Avoidance behavior prevents children from learning math, impairing their performance. Cognitive behavioral therapy is an approach with robust evidence of efficacy in treating anxiety disorders. The Coping Cat, a protocol for treating anxiety disorders, inspired the MA intervention reported here. The participant was N. L., an 11-year-old female displaying math-related and math-unrelated anxiety symptoms. Outcome measures included arithmetic performance, and self-reports of general positive and negative affect and math-related self-perceived performance, attitude, unhappiness and anxiety. The therapeutic approach included psychoeducation, relaxation, diaphragmatic breathing, cognitive restructuring, problem-solving training and graded exposure. After 12 individual intervention sessions, there was an improvement in negative and positive affect, as well as an improvement in self-perceived performance and a decrease in MA.

A ansiedade matemática (AM) pode ser definida como sentimento de tensão e ansiedade ao se manipular estímulos numéricos. O comportamento de esquiva, típico da ansiedade, impede que a criança treine matemática, prejudicando seu desempenho. A terapia cognitivo-comportamental é uma abordagem com evidências robustas de eficácia no tratamento da ansiedade e, ao longo do tempo, diversos protocolos de intervenção foram desenvolvidos para esse distúrbio. Um protocolo infantil conhecido por sua eficácia é o Coping Cat, o qual inspirou a elaboração da intervenção para AM do presente estudo. N. L., 11 anos, foi classificada como superior em uma escala de AM. Após 12 sessões de intervenção individuais, ela alcançou escores médios na mesma escala. As técnicas utilizadas foram psicoeducação, respiração diafragmática, relaxamento, reestruturação cognitiva, treinamento de resolução de problemas e exposição.

Nonsymbolic and Symbolic Numerical Magnitude Processing in the Brazilian Children with Mathematics Difficulties.

It is still debated if the main deficit in mathematical difficulties (MD) is nonsymbolic or symbolic numerical magnitude processing. Objectives: In the present study, our main goal was to investigate nonsymbolic and symbolic numerical magnitude processing in MD and the relationship between these abilities and arithmetic. Methods: The Brazilian school-age children with MD completed a nonsymbolic and a symbolic numerical magnitude comparison task and an arithmetic task. We compared their performance with a group of children with typical achievement (TA) and investigated the association between numerical magnitude processing and arithmetic with a series of regression analyses. Results: Results indicated that children with MD had low performance in the nonsymbolic numerical magnitude comparison task. Performance in both nonsymbolic and symbolic numerical magnitude comparison tasks predicted arithmetic abilities in children with TA, but not in children with MD. Conclusions: These results indicate that children with MD have difficulties in nonsymbolic numerical magnitude processing, and do not engage basic numerical magnitude representations to solve arithmetic.

Ainda é debatido se o principal déficit nas dificuldades matemáticas (DM) se dá no processamento de magnitudes numéricas não simbólicas ou simbólicas. Objetivos: No presente estudo, nosso principal objetivo foi investigar o processamento não simbólico e simbólico de magnitudes numéricas na DM e a relação entre essas habilidades e a aritmética. Métodos: Crianças brasileiras em idade escolar com DM completaram tarefas de comparação de magnitudes numéricas não simbólicas e simbólicas e uma tarefa aritmética. Comparamos seu desempenho com o de um grupo de crianças com desempenho típico (TA) e investigamos a associação entre o processamento de magnitude numérica e a aritmética em uma série de análises de regressão. Resultados: Os resultados indicaram baixo desempenho na tarefa de comparação de magnitudes numéricas não simbólicas nas crianças com DM. Além disso, o desempenho nas tarefas de comparação de magnitudes numéricas não simbólicas e simbólicas foi preditor de habilidades aritméticas de crianças com TA, mas não de crianças com DM. Conclusões: Esses resultados indicam que crianças com DM têm dificuldades no processamento de magnitudes numéricas não simbólicas e não empregam representações básicas de magnitudes numéricas para resolver problemas aritméticos.

The quandary of diagnosing mathematical difficulties in a generally low performing population.

Brazilian students' mathematical achievement was repeatedly observed to fall below average levels of mathematical attainment in international studies such as PISA. OBJECTIVE: In this article, we argue that this general low level of mathematical attainment may interfere with the diagnosis of developmental dyscalculia when a psychometric criterion is used establishing an arbitrary cut-off (e.g., performance

O desempenho em matemática dos estudantes brasileiros mostra-se consistentemente abaixo da média mundial em estudos internacionais como o PISA. OBJETIVO: No presente artigo, argumenta-se que um baixo desempenho geral na matemática, a exemplo dos estudantes brasileiros, pode interferir no diagnóstico de discalculia do desenvolvimento quando um critério puramente psicométrico é usado para estabelecer um ponto de corte arbitrário (por exemplo, desempenho

Inattention Symptoms are Predictors of Neuropsychological Functioning in Children from 3rd and 4th Grades.

Symptoms of inattention and hyperactivity/impulsivity, arranged along a continuum, are commonly associated with neuropsychological and academic deficits, even in the general population. The aim of this study is to analyze how Attention Deficit Hyperactivity Disorder (ADHD) symptoms are associated with the performance in neuropsychological and academic abilities (phonological processing, processing speed/automatic attention, executive functions, reading, and spelling) in school-age children. The sample consisted of 216 children from 3rd and 4th grades (M = 8.94 years old, SD =.71) from public elementary schools of two Brazilian capitals. Pearson correlation and Multiple Linear Regression analysis were performed. Inattention symptoms were the only predictors of performance in phonological processing (phoneme suppression and rapid automatized naming of letters), processing speed/automatic attention, executive functions, such as inhibitory control and cognitive flexibility, and reading fluency. Beta values ranged from .14 to .27, and the largest value was related to an inhibitory control task. Inattention, and not hyperactivity/impulsivity symptoms, seems to affect neuropsychological functions even in non-clinical diagnosed children. Contributions and future directions are discussed.

Motor Imagery Development in Children: Changes in Speed and Accuracy With Increasing Age.

Although motor imagery has been pointed as a promising strategy for the rehabilitation of children with neurological disorders, information on their development throughout childhood and adolescence is still scarce. For instance, it is still unclear at what age they reach a development comparable to the motor imagery performance observed in adults. Herein we used a mental rotation task to assess motor imagery in 164 typically developing children and adolescents, which were divided into four age groups (6-7, 8-9, 10-11, and 12-13 years) and 30 adults. The effects of biomechanical constraints, accuracy, and reaction time of the mental rotation task were considered. ANOVA showed that all groups had the effect of biomechanical restrictions of the mental rotation task. We found a group effect for accuracy [F (4, 180) = 17,560; p < 0.00; η2 = 3.79] and reaction time [F (4, 180) = 17.5; p < 0.001, η2 = 0.615], with the results of children groups 6-7 and 8-9 years being significantly lower than the other groups (p < 0.05). In all the analyses, there were no differences regarding accuracy and reaction time among the participants of the age groups 10-11 and 12-13 years and adults (p > 0.05). Concluding, children aged 6-7 years were able to perform motor imagery, motor imagery ability improved as the participants' ages increased, and children aged 10 and over-performed similarly to adults.

Effect of motor imagery combined with physical practice on upper limb rehabilitation in children with hemiplegic cerebral palsy.

INTRODUCTION: Evidence indicates that motor deficits in hemiplegic cerebral palsy (HCP) impair both motor execution and planning. However, current rehabilitation efforts focus mainly on relieving impairments in motor execution. Motor imagery (MI) is a promising method for stimulating neural networks underlying the planning and control of movements. OBJECTIVE: Evaluate the effectiveness of MI combined with physical practice in improving the function of the upper limbs in children with HCP. METHOD: Twenty-four participants, aged 7-14 years were divided into two groups: intervention group (IG) and control group (CG). The IG was subjected to MI training and physical practice twice a week for eight consecutive weeks, while the CG received conventional therapy. Participants were assessed with the Assisting Hand Assessment (AHA) at pre-intervention, post-intervention, and follow up. RESULTS: The results showed improved motor functions in both groups. Analysis using the general linear model (analysis of covariance) and Bonferroni post hoc tests showed significant improvements from pre-intervention to post-intervention in the AHA for the IG. The CG showed non-significant improvement in AHA scores. CONCLUSIONS: These findings suggest that the MI training, combined with the physical practice program used in this study, was effective in improving upper limb function in children with HCP.

Are "cool" executive function impairments more salient in ADHD symptoms than in reading disability?

INTRODUCTION: Reading disability (RD) and Attention Deficit Hyperactivity Disorder (ADHD) symptoms often co-occur in school-age children. METHODS: The present study evaluated the performance of 216 Brazilian children from 3rd and 4th grades on "cool" executive function (EF) abilities and phonological processing. The children were divided into three groups: those with ADHD symptoms only, those with RD only, and controls. RESULTS: MANOVA analyses, controlling for age and nonverbal intelligence, showed worse performance for the RD group, compared to the ADHD symptoms group, on measures of phonological processing (phonemic awareness, phonological short-term memory, and lexical access) and "cool" EF components (orthographic verbal fluency and processing speed). The ADHD symptoms group did not differ from the control group on the majority of the "cool" EF tasks. Compared to the control group, the ADHD symptoms group and the RD group both showed significantly more errors in rapid automatized naming of figures, which evaluates the inhibition component of EF; performance on this task was similar for these groups. CONCLUSION: We conclude that children with RD have greater impairment in phonological processing and "cool" EF compared to those with ADHD symptoms. Furthermore, deficits in inhibitory control may be shared among children with both conditions.

INTRODUÇÃO: Dificuldades de leitura (DL) e sintomas do Transtorno de Déficit de Atenção e Hiperatividade (TDAH) frequentemente coocorrem em crianças escolares. MÉTODOS: O presente estudo comparou o desempenho em FE "frias" e processamento fonológico de 216 crianças brasileiras de 3ª e 4ª anos, que foram divididas em três grupos: apenas com sintomas de TDAH, apenas em DL e controles. RESULTADOS: As análises de MANOVA, controlando para idade e inteligência não-verbal, indicaram que o grupo com DL apresentou desempenho significativamente inferior ao grupo com sintomas de TDAH nas medidas de processamento fonológico (consciência fonológica, memória verbal de curto prazo e acesso lexical) e em componentes das FE "frias" (fluência verbal ortográfica e velocidade de processamento). O grupo com sintomas de TDAH não se diferiram do grupo controle na maior parte das tarefas de FE "frias". Ambos os grupos com sintomas de TDAH e DL apresentaram desempenhos significativamente menores (mais erros) em comparação às crianças de desenvolvimento típico na tarefa de Nomeação Seriada Rápida de figuras que avalia o componente de controle inibitório, e o desempenho foi semelhante entre os grupos. CONCLUSÃO: Conclui-se que crianças com DL apresentam maior comprometimento em processamento fonológico e FE "frias" em comparação àquelas com sintomas de TDAH e que déficits no controle inibitório podem ser compartilhados entre crianças com ambas as condições.

Intragroup differences and similarities in performance on rapid automatized naming tasks in children with ADHD symptoms, children with reading disabilities, and controls.

Introduction Rapid automatized naming (RAN) is the ability to name, as fast as possible, symbols such as letters, digits and figures. The present study aimed to investigate intragroup performance patterns on RAN tasks in children with attention deficit hyperactivity disorder (ADHD) symptoms alone, children with reading disability (RD) alone and controls with typical development. Methods A total of 216 Brazilian children between 8 to 11 years old were selected from public schools located in two Brazilian capitals, namely Porto Alegre and Belo Horizonte, to participate in the study. Mixed 3 (participant group: ADHD symptoms, RD or control group) × 3 (type of stimulus: letters, numbers or figures) ANOVAs were performed using response time and number of errors as dependent variables. Only intragroup comparisons are described in this paper. Results The groups with ADHD symptoms and RD showed similar performance results on naming speed. There were no differences between letters and numbers within each group, but we found slower responses in figure naming compared to the other tasks for both groups. Concerning accuracy, children with ADHD symptoms showed a similar number of errors in all three tasks. These patterns were distinct from the performance of the control group. Conclusion Results suggest a shared deficit in naming speed of alphanumeric stimuli in children with ADHD symptoms and those with RD, and impairments in naming digits correctly in children with ADHD symptoms.

Neuropsychological and environmental predictors of reading performance in Brazilian children.

Word-level reading is strongly associated with phonological processing. The aim of this study was to investigate the effects of cognitive and environmental variables on word reading performance. Our sample consisted of 185 fourth-grade students. Linear regression analyses were used to investigate the role of the following variables as potential predictors of word reading accuracy and fluency: phonological processing (phonological awareness, rapid automatized naming, and phonological memory); verbal fluency; working memory; socioeconomic status and an indicator of school quality (IDEB) in Brazil. Phonological awareness and rapid automatic naming were the best predictors of reading, supporting the role of phonological processing as a key contributor to the lexical aspects of reading, beyond the early years of literacy acquisition. Environmental variables were significant predictors of irregular word reading (socioeconomic status) and fluency (IDEB), corroborating multicomponent models of reading performance. The present findings demonstrate the complex interplay of factors underlying reading performance and highlight the importance of a multidimensional approach to the study of reading.

The Mini-Mental Examination for Children (MMC): Evidence of validity for children with learning difficulties.

The Mini-Mental Examination for Children (MMC) is a widely used tool for assessing global cognitive deficits, however,is still unknown whether MMC is sensitive for investigating cognitive profiles associated with learning difficulties (LD). OBJECTIVE: Here we investigate the feasibility of using the MMC for screening school-aged children with learning difficulties in spelling and math. METHODS: The MMC and other neurophysiological tests were administered to a sample of 168 children, aged 7 to 12 years. The sample was subdivided into a Control group and LD group (Math Difficulties, Spelling Difficulties, Math and Spelling Difficulties). Diagnostic accuracy was assessed with ROC analysis. Convergent and divergent validity was assessed using correlation analysis. RESULTS: Performance on the MMC was associated with nonverbal intelligence, age and school achievement. The LD group had significantly lower performance on the MMC than the Control group. Performance on the MMC discriminated LD children with a global accuracy of around 0.80. Associations between the MMC and the other neuropsychological variables were higher for finger gnosis (r=0.40) and generally higher for early elementary school grades. The MMC proved satisfactory for identifying LD children with good accuracy. Nonverbal intelligence, and perceptual/motor abilities play an important role in MMC performance. CONCLUSION: The MMC could be a useful instrument for screening children with LD.

Mini-exame mental para crianças (MMC) é uma ferramenta amplamente utilizada para avaliar déficits cognitivos globais, no entanto, ainda é desconhecido se a MMC é sensível para investigar perfis cognitivos associados a dificuldades de aprendizagem. OBJETIVO: Aqui nós investigamos a viabilidade de usar MMC para triagem de crianças em idade escolar com dificuldades de aprendizagem em ortografia e matemática. MÉTODOS: MMC e outros testes neuropsicológicos foram administrados em uma amostra de 168 crianças de 7 a 12 anos de idade. A amostra foi subdividida em um Grupo Controle e um grupo LD (dificuldade na matemática, na escrita, ou na escrita e na matemática). A acurácia diagnóstica foi analisada através de uma análise de curva ROC. A validade convergente e divergente foi investigada através de análises de correlações. RESULTADOS: A performance no MMC foi associada com a inteligência não verbal, idade e desempenho escolar. O grupo LD apresentou desempenho significativamente inferior ao Grupo Controle no MMC. A performance no MMC pôde identificar crianças LD com uma acurácia global em torno de 0.80. As associações entre MMC e outras variáveis neuropsicológicas foram maiores para gnosias digitais (r=0.40) e em geral, mais altas nas séries iniciais. O MMC se mostrou satisfatório para identificar crianças LD com uma boa acurácia. A inteligência não verbal, habilidades perceptivas/motoras tem um importante papel na performance no MMC. CONCLUSÃO: O MMC pode ser um instrumento útil para o rastreamento de crianças com LD.

Heterosis in COMT Val158Met Polymorphism Contributes to Sex-Differences in Children's Math Anxiety.

Math anxiety (MA) is a phobic reaction to math activities, potentially impairing math achievement. Higher frequency of MA in females is explainable by the interaction between genetic and environmental factors. The molecular-genetic basis of MA has not been investigated. The COMT Val158Met polymorphism, which affects dopamine levels in the prefrontal cortex, has been associated with anxiety manifestations. The valine allele is associated with lower, and the methionine allele with higher, dopamine availability. In the present study, the effects of sex and COMT Val158Met genotypes on MA were investigated: 389 school children aged 7-12 years were assessed for intelligence, numerical estimation, arithmetic achievement and MA and genotyped for COMT Val158Met polymorphism. The Math Anxiety Questionnaire (MAQ) was used to assess the cognitive and affective components of MA. All genotype groups of boys and girls were comparable regarding genotype frequency, age, school grade, numerical estimation, and arithmetic abilities. We compared the results of all possible genetic models: codominance (Val/Val vs. Val/Met vs. Met/Met), heterosis (Val/Met vs. Val/Val plus Met/Met), valine dominance (Val/Val plus Val/Met vs. Met/Met), and methionine dominance (Met/Met plus Val/Met vs. Val/Val). Models were compared using AIC and AIC weights. No significant differences between girls and boys and no effects of the COMT Val158Met polymorphism on numerical estimation and arithmetic achievement were observed. Sex by genotype effects were significant for intelligence and MA. Intelligence scores were higher in Met/Met girls than in girls with at least one valine allele (valine dominance model). The best fitting model for MA was heterosis. In Anxiety Toward Mathematics, heterozygous individuals presented MA levels close to the grand average regardless of sex. Homozygous boys were significantly less and homozygous girls significantly more math anxious. Heterosis has been seldom explored, but in recent years has emerged as the best genetic model for some phenotypes associated with the COMT Val158Met polymorphism. This is the first study to investigate the genetic-molecular basis of MA.