Writing problems in developmental dyslexia: under-recognized and under-treated

Chinese handwriting performance of primary school children with dyslexia

The aim of this study was to investigate the Chinese handwriting performance of typical children and children with dyslexia, and to examine whether speed and accuracy of handwriting could reliably discriminate these two groups of children. One hundred and thirty-seven children with dyslexia and 756 typical children were recruited from main stream primary schools for the study. They were requested to copy 90 Chinese characters using the Chinese Handwriting Assessment Tool (CHAT) jointly developed by a project team from two universities in Hong Kong. The process of handwriting was recorded and the stroke errors in writing were analyzed using the CHAT system. Results indicated that children with dyslexia wrote significantly slower, with greater average character size and variation in size (p<.05) than the typical children of same age group. They also wrote with significantly lower accuracy (p<.05). Commonly observed writing errors among the Dyslexic group were missing strokes and concatenated strokes. From the discriminant analysis, it was found that writing speed and accuracy were satisfactory discriminators that could discriminate students into the two groups, with reasonably good classification accuracy of over 70% for every grade. The results were discussed with theoretical implications in relation to fine motor skills, kinesthetic abilities, visual perceptual skills, and the demand of written tasks in school.

Desempenho ortográfico de escolares do 2º ao 5º ano do ensino público

OBJETIVOS: Caracterizar, comparar e classificar o desempenho de escolares do 2º ao 5º ano do ensino público segundo a semiologia dos erros. MÉTODOS: Participaram deste estudo 120 escolares do 2º ao 5º ano de escola pública municipal de Marília-SP, sendo 30 de cada série, divididos em quatro grupos: GI (2º ano); GII (3º ano); GIII (4º ano); e GIV (5º ano). Como procedimento foram aplicadas as provas do Pro-Ortografia: versão coletiva (escrita de letras do alfabeto, ditado randomizado das letras do alfabeto, ditado de palavras, ditado de pseudopalavras, ditado com figuras, escrita temática induzida por figura) e versão individual (ditado de frases, erro proposital, ditado soletrado, memória lexical ortográfica). RESULTADOS: Houve diferença na comparação intergrupos, indicando melhor desempenho dos escolares a cada série subsequente, na maior parte das provas da versão coletiva e individual. Com o avanço da seriação escolar, os grupos apresentaram menor média de erros na escrita. CONCLUSÃO: O perfil de aquisição da ortografia do sistema de escrita do Português observado em escolares do ensino público é indicativo do funcionamento normal de desenvolvimento da escrita infantil.

Global processing speed in children with low reading ability and in children and adults with typical reading ability: exploratory factor analytic models

PURPOSE

To investigate processing speed as a latent dimension in children with dyslexia and children and adults with typical reading skills.

METHOD

Exploratory factor analysis (FA) was based on a sample of multigenerational families, each ascertained through a child with dyslexia. Eleven measures--6 of them timed--represented verbal and nonverbal processes, alphabet writing, and motor sequencing in the hand and oral motor system. FA was conducted in 4 cohorts (all children, a subset of children with low reading scores, a subset of children with typical reading scores, and adults with typical reading scores; total N = 829).

RESULTS

Processing speed formed the first factor in all cohorts. Both measures of motor sequencing speed loaded on the speed factor with the other timed variables. Children with poor reading scores showed lower speed factor scores than did typical peers. The speed factor was negatively correlated with age in the adults.

CONCLUSIONS

The speed dimension was observed independently of participant cohort, gender, and reading ability. Results are consistent with a unified theory of processing speed as a quadratic function of age in typical development and with slowed processing in poor readers.

Efficacy of an Explicit Handwriting Program

The aim of this study was to investigate the effects of an explicit handwriting program introduced during the first grade of elementary school. Grade 1 children ( N = 23) with an age range of 6.1 to 7.4 yr. (15 girls, 8 boys) were administered an additional handwriting program of two weekly sessions of 45 min. over six weeks. Another group of 19 Grade 1 children (11 girls, 8 boys) received only the regular handwriting program of one weekly session. The Concise Assessment Scale for Children's Handwriting was administered to measure the changes in quality and speed of handwriting. The children given the explicit program showed better quality and speed of handwriting than did the control group. Their handwriting was more regular, with fewer ambiguous letters and fewer incorrect relative heights.

Evidence-based diagnosis and treatment for specific learning disabilities involving impairments in written and/or oral language

Programmatic, multidisciplinary research provided converging brain, genetic, and developmental support for evidence-based diagnoses of three specific learning disabilities based on hallmark phenotypes (behavioral expression of underlying genotypes) with treatment relevance: dysgraphia (impaired legible automatic letter writing, orthographic coding, and finger sequencing), dyslexia (impaired pseudoword reading, spelling, phonological and orthographic coding, rapid automatic naming, and executive functions; inhibition and rapid automatic switching), and oral and written language learning disability (same impairments as dyslexia plus morphological and syntactic coding and comprehension). Two case studies illustrate how these differential diagnoses can be made within a conceptual framework of a working memory architecture and generate treatment plans that transformed treatment nonresponders into treatment responders. Findings are discussed in reference to the importance of (a) considering individual differences (diagnosis of impaired hallmark phenotypes) in planning and evaluating response to instruction and modifying instruction when a student is not responding; (b) recognizing that teaching may change epigenetic gene expression at one stage of schooling, but not the underlying gene sequences that render individuals still vulnerable as curriculum requirements increase in nature, complexity, and volume in the upper grades; and (c) using evidence-based diagnoses of specific learning disabilities that are consistent across states for free and appropriate education K to 12 and for accommodations throughout higher education and professional credentialing.

Replication of CNTNAP2 association with nonword repetition and support for FOXP2 association with timed reading and motor activities in a dyslexia family sample

Two functionally related genes, FOXP2 and CNTNAP2, influence language abilities in families with rare syndromic and common nonsyndromic forms of impaired language, respectively. We investigated whether these genes are associated with component phenotypes of dyslexia and measures of sequential motor ability. Quantitative transmission disequilibrium testing (QTDT) and linear association modeling were used to evaluate associations with measures of phonological memory (nonword repetition, NWR), expressive language (sentence repetition), reading (real word reading efficiency, RWRE; word attack, WATT), and timed sequential motor activities (rapid alternating place of articulation, RAPA; finger succession in the dominant hand, FS-D) in 188 family trios with a child with dyslexia. Consistent with a prior study of language impairment, QTDT in dyslexia showed evidence of CNTNAP2 single nucleotide polymorphism (SNP) association with NWR. For FOXP2, we provide the first evidence for SNP association with component phenotypes of dyslexia, specifically NWR and RWRE but not WATT. In addition, FOXP2 SNP associations with both RAPA and FS-D were observed. Our results confirm the role of CNTNAP2 in NWR in a dyslexia sample and motivate new questions about the effects of FOXP2 in neurodevelopmental disorders.

Genome scan for spelling deficits: effects of verbal IQ on models of transmission and trait gene localization

Dyslexia is a complex learning disability with evidence for a genetic basis. Strategies that may be useful for dissecting its genetic basis include the study of component phenotypes, which may simplify the underlying genetic complexity, and use of an analytic approach that accounts for the multilocus nature of the trait to guide the investigation and increase power to detect individual loci. Here we present results of a genetic analysis of spelling disability as a component phenotype. Spelling disability is informative in analysis of extended pedigrees because it persists into adulthood. We show that a small number of hypothesized loci are sufficient to explain the inheritance of the trait in our sample, and that each of these loci maps to one of four genomic regions. Individual trait models and locations are a function of whether a verbal IQ adjustment is included, suggesting mediation through both IQ-related and unrelated pathways.

Note-taking skills of middle school students with and without learning disabilities

For middle school students with learning disabilities (LD), one major component of learning in content area classes, such as science, involves listening to lectures and recording notes. Lecture learning and note-taking are critical skills for students to succeed in these classes. Despite the importance of note-taking skills, no research has been reported on the problems that school-age students with LD encounter when recording notes during science lectures. Using a sample size of 90 middle school students, the performance of students with LD was compared to students with no learning disabilities (NLD). Results found that students with LD performed significantly worse than students with NLD in terms of the type and amount of notes recorded and test performance.

Avaliação de escrita na dislexia do desenvolvimento: tipos de erros ortográficos em prova de nomeação de figuras por escrita

OBJETIVO: avaliar o padrão de resposta de disléxicos em uma tarefa de nomeação de figuras por escrita, por meio da análise dos tipos de erros ortográficos cometidos. MÉTODOS: o desempenho de um grupo de 15 disléxicos foi comparado ao de dois grupos controles, pareados por idade e por nível de leitura. RESULTADOS: os grupos dislexia e controle por leitura não diferiram quanto ao número de acertos, mas ambos acertaram menos que o grupo controle por idade. Com relação aos tipos de erros, foram observadas diferenças significantes com maior número de erros entre disléxicos para erros de correspondência unívoca grafema-fonema, omissão de segmentos e correspondência fonema-grafema independente de regras. CONCLUSÃO: conclui-se que a análise dos erros ortográficos é útil para a compreensão das estratégias utilizadas e dos processos lingüísticos subjacentes às dificuldades de escrita em indivíduos com dislexia.

Inter-relationships among behavioral markers, genes, brain and treatment in dyslexia and dysgraphia

Cross-country, longitudinal twin studies provide strong evidence for both the biological and environmental basis of dyslexia, and the stability of genetic influences on reading and spelling, even when skills improve in response to instruction. Although DNA studies aimed at identifying gene candidates in dyslexia and related phenotypes (behavioral expression of underlying genotypes); and imaging studies of brain differences between individuals with and without dyslexia and the brain's response to instructional treatment are increasing, this review illustrates, with the findings of one multidisciplinary research center, an emerging trend to investigate the inter-relationships among genetic, brain and instructional treatment findings in the same sample, which are interpreted in reference to a working-memory architecture, for dyslexia (impaired decoding and spelling) and/or dysgraphia (impaired handwriting). General principles for diagnosis and treatment, based on research with children who failed to respond to the regular instructional program, are summarized for children meeting research criteria for having or being at risk for dyslexia or dysgraphia. Research documenting earlier emerging specific oral language impairment during preschool years associated with reading and writing disabilities during school years is also reviewed. Recent seminal advances and projected future trends are discussed for linking brain endophenotypes and gene candidates, identifying transchromosomal interactions, and exploring epigenetics (chemic al modifications of gene expression in response to developmental or environmental changes). Rather than providing final answers, this review highlights past, current and emerging issues in dyslexia research and practice.

Relationship of word- and sentence-level working memory to reading and writing in second, fourth, and sixth grade

PURPOSE

The purpose of this study was to evaluate the contribution of working memory at the word and sentence levels of language to reading and writing outcomes.

METHOD

Measures of working memory at the word and sentence levels, reading and writing, were administered to 2nd (N = 122), 4th (N = 222), and 6th (N = 105) graders. Structural equation modeling was used to evaluate whether the 2 predictor working memory factors contributed unique variance beyond their shared covariance to each of 5 outcome factors: handwriting, spelling, composing, word reading, and reading comprehension.

RESULTS

At each grade level, except for handwriting and composing in 6th grade, the word-level working memory factor contributed unique variance to each reading and writing outcome. The text-level working memory factor contributed unique variance to reading comprehension in 4th and 6th grade.

DISCUSSION

The clinical significance of these findings for assessment and intervention is discussed.

Functional magnetic resonance imaging sequential-finger movement activation differentiating good and poor writers

Good and poor fifth-grade writers differed, after controlling for multiple comparisons, in 42 brain regions on group maps and then individual brain analyses for functional magnetic resonance imaging (fMRI) contrast between tapping adjacent fingers sequentially and same finger repeatedly. Of these, 11 regions were correlated with both handwriting and spelling (transcription). Gender differences on the fMRI contrast, with girls more activated, occurred only in left superior parietal, which was correlated with handwriting and spelling. Significance of serial organization of fingers for handwriting and spelling is discussed.

A multidisciplinary approach to understanding developmental dyslexia within working-memory architecture: genotypes, phenotypes, brain, and instruction

A unifying theoretical framework of three working memory components provides a systems perspective for discussing past and new findings in a 12-year research program that point to heterogeneity in the genetic and brain basis and behavioral expression of dyslexia: (a) codes for word-form storage and processing, (b) time-sensitive phonological and orthographic loops for maintaining information in working memory or outputting it, and (c) executive functions for language (e.g., rapid automatic switching of attention). Results, which span the genetic to neurological to behavioral levels of analysis, point to possible impairment in any one or combination of these working memory components in individuals with dyslexia. A DNA variation on chromosome 15 may be linked with the phonological word-form in the first working-memory component. A DNA variation on chromosome 6 may be linked with slow rapid automatic switching, inattention ratings, and impaired goal-directed activity ratings in the third working-memory component. Brain and behavioral findings support (a) Triple Word Form Theory: phonological, orthographic, and morphological word-forms and their parts contribute to learning to read and spell words; and (b) Cross-Word Form Mapping: in the process of learning to read and spell words children compute the inter-relationships among the three word-forms and their parts. However, children with dyslexia may require more focus on the morphological word-form and its parts and their relationships with the other two word-forms and their parts than do normal readers. Also, children with dyslexia have unusual difficulties in sustaining phonological loop function in working memory over time; their impaired orthographic loop function may interfere with learning to write alphabet letters and spell, which may be as impaired as word decoding and reading. Impaired executive functions may interfere with the efficiency of working memory in processing oral and written language.

Technical features of curriculum-based measures for beginning writers

The purpose of the two studies reported in this article was to examine technical features of curriculum-based measures for beginning writers. In Study 1, 50 first graders responded to word copying, sentence copying, and story prompts. In Study 2, 50 additional first graders responded to letter, picture-word, picture-theme, and photo prompts. In both studies, 3- to 5-minute prompts were administered in winter and spring and scored using a variety of quantitative procedures. Students were also administered the Test of Written Language-Third Edition , and teacher ratings and scores on a district rubric for writing were collected. Test-retest (Study 1 only) and alternate-form reliability, criterion validity, and winter-to-spring growth were examined for each measure. Sentence-copying, story, picture-word, and photo prompts emerged as promising beginning-writing measures. Findings have implications for monitoring student progress within a seamless and flexible system across ages and skill levels.