Reading Disabilities (RD) and Attention Deficit/Hyperactivity Disorder (ADHD) are common neurodevelopmental disorders with evidence for shared genetic etiology. This study examined four predicted neuronal migration genes in RD (DCDC2, KIAA0319, DCDC2B and NEDD4L), and three of these genes in ADHD (DCDC2, DCDC2B and NEDD4L). Putative regulatory elements of DCDC2 (6p) and KIAA0319 (6p) were screened to identify functional risk variants that explain previous association findings. No statistically significant associations were observed in DCDC2. In KIAA0319, variants with predicted regulatory function showed association with RD. This supports the hypothesis that causal RD risk variants in KIAA0319 alter gene expression. DCDC2B (1p), the homolog of DCDC2, showed suggestive evidence for association to ADHD, but not RD. Previous association findings in NEDD4L (18q) could not be replicated. No pleiotropic gene for RD and ADHD was identified. However, together with previous findings, this study supports that neuronal migration may be a common underlying deficit in both RD and ADHD.

Reading Disabilities (RD) and Attention Deficit/Hyperactivity Disorder (ADHD) are common neurodevelopmental disorders with evidence for shared genetic etiology. This study examined four predicted neuronal migration genes in RD (DCDC2, KIAA0319, DCDC2B and NEDD4L), and three of these genes in ADHD (DCDC2, DCDC2B and NEDD4L). Putative regulatory elements of DCDC2 (6p) and KIAA0319 (6p) were screened to identify functional risk variants that explain previous association findings. No statistically significant associations were observed in DCDC2. In KIAA0319, variants with predicted regulatory function showed association with RD. This supports the hypothesis that causal RD risk variants in KIAA0319 alter gene expression. DCDC2B (1p), the homolog of DCDC2, showed suggestive evidence for association to ADHD, but not RD. Previous association findings in NEDD4L (18q) could not be replicated. No pleiotropic gene for RD and ADHD was identified. However, together with previous findings, this study supports that neuronal migration may be a common underlying deficit in both RD and ADHD.

The performance of 223 Grade 4 children, with Average overall IQ and no disability (ND), or reading disability (RD), or math disability (MD), or reading/math disability (RD+MD), was compared on theoretically-derived factors measuring specific cognitive processes underlying reading and math achievement. The processes included automatic visual/orthographic and visual/math fact retrieval, working memory span, phonological and algorithmic processing, and IQ (e.g., verbal/nonverbal reasoning). Good readers and good mathematicians (ND group) showed solid performance across all tasks. Compared to the ND group, achievement and cognitive profiles of single disability (RD and MD), and RD+MD were elucidated. Structural equation models (SEM) for the entire sample confirmed a theoretically-derived four factor READ model and a four factor MATH model, both with identical Working Memory Span and IQ factors. Two other READ model factors were Automatic (RAN/Words) and Phonological Processing. Two additional MATH model factors were Automatic (RAN/Facts) and Algorithmic Processing. Based on the cognitive and functional neurobiological literatures, these models supported a systems view of the unique and collaborative relations among the automatic, processing, working memory, and IQ cognitive processes underlying reading and math achievement. Through regression analyses, the specific factors from both the READ and MATH models predicted each group’s reading and math achievement. Regression results enhanced our understanding of what factors/cognitive processes (strong or weak) contribute to good or poor reading and math achievement. Findings that automatic RAN/Words and RAN/Facts both predict fluent math fact retrieval for all groups suggest potential overlap in basic automatic visual/orthographic and visual/fact routes. Possible overlap in these automatic processes was also seen in the weakest RD+MD group for word reading.

The performance of 223 Grade 4 children, with Average overall IQ and no disability (ND), or reading disability (RD), or math disability (MD), or reading/math disability (RD+MD), was compared on theoretically-derived factors measuring specific cognitive processes underlying reading and math achievement. The processes included automatic visual/orthographic and visual/math fact retrieval, working memory span, phonological and algorithmic processing, and IQ (e.g., verbal/nonverbal reasoning). Good readers and good mathematicians (ND group) showed solid performance across all tasks. Compared to the ND group, achievement and cognitive profiles of single disability (RD and MD), and RD+MD were elucidated. Structural equation models (SEM) for the entire sample confirmed a theoretically-derived four factor READ model and a four factor MATH model, both with identical Working Memory Span and IQ factors. Two other READ model factors were Automatic (RAN/Words) and Phonological Processing. Two additional MATH model factors were Automatic (RAN/Facts) and Algorithmic Processing. Based on the cognitive and functional neurobiological literatures, these models supported a systems view of the unique and collaborative relations among the automatic, processing, working memory, and IQ cognitive processes underlying reading and math achievement. Through regression analyses, the specific factors from both the READ and MATH models predicted each group’s reading and math achievement. Regression results enhanced our understanding of what factors/cognitive processes (strong or weak) contribute to good or poor reading and math achievement. Findings that automatic RAN/Words and RAN/Facts both predict fluent math fact retrieval for all groups suggest potential overlap in basic automatic visual/orthographic and visual/fact routes. Possible overlap in these automatic processes was also seen in the weakest RD+MD group for word reading.

There is agreement in the learning disability (LD) literature that reading problems in children can be attributed to difficulties in coding linguistic information. One explanation for this is that students with LD have impaired verbal memory ability. However, the specific mechanisms underlying these memory impairments are not well understood, especially in adolescents. The purpose of the current study was to compare the memory performance of adolescent students with specific reading disabilities (RD) to normal adolescent readers on a newly developed verbal learning test. The Bergen-Tucson Verbal Learning Test (BTVLT), English version, modeled after the California Verbal Learning Test (CVLT), is a multiple trial test designed to measure memory acquisition, retention, retrieval, and forgetting rates, as well as the ability to organize and retrieve the information from memory according to the phonological (surface) and semantic (lexical) features of words. Twenty subjects with RD and 20 control subjects with a mean age of 15.2 years, matched for age, gender, and ethnicity, participated in the study. Results indicated that the RD group learned significantly fewer list items and did so at a slower rate than the controls. Although the RD group was equally able to retain information once learned, they did demonstrate inefficient elaborative rehearsal strategies. The RD group also recalled fewer words in both the semantic and phonetic cued recall conditions, but the effect size was significantly greater in the phonetic cued recall condition. Taken together, the data suggest that students with RD have less efficient rehearsal and encoding mechanisms but normal retention. Retrieval also appears normal except under conditions that require information to be recalled based on phonetic codes.

Submitted in partial fulfillment of the requirements for the degree MASTER OF EDUCATION in the Department of Educational Psychology and Special Needs Education of the Faculty of Education at the University of Zululand, 2008. / The aim of this study was to pursue an investigation into the impact reading disabilities have on the academic achievement of a primary school learner. From the literature study it became evident that learners with reading problems are faced with a lot of problems in primary schools. These problems are manifest in the form of prejudice stigmatization, humiliation and pressure as they often find the teaching and learning materials beyond their scope of comprehension. There is a need for educator support so that they can fine-tune their instruction to suit the level of the learners with reading problems and for educators to garner the support of parents who may be uninterested about what obtains at school. Learners with reading problems can be helped by educators whose learning activities are well planned and prepared and their presentation has to captivate the learner’s attention, interest and involvement. If learners with reading problems do not receive adequate support, they may exhibit the following:  Behavioural problems e.g. being disobedient to the educator.  Have a low frustration threshold.  Develop a negative self-esteem.  Set unrealistic goals for themselves.  Ultimately drop out of school.  Play truant  Shirk their school work.  Absent themselves from school. Nevertheless, educators need to create a stimulating atmosphere, to exploit reinforcement strategies and set good examples, such as:  Tangible motivators, for example, stars, edibles (nuts and fruits), cinema tickets, colouring books.  Activity orientated motivators such as helping the educator, free play, watching television, painting or drawing.  Social motivators, such as a smile, nod of head etc. In conclusion a summary was presented on the findings of the literature and empirical study and recommendations are made based on the nature of assistance required by the educators in order to help the learner with reading problems. The recommendations touched on remedial approaches and teaching activities that educators need to utilize to help the reading disabled learner. Further research should be conducted on barriers to learning that could emanate from inappropriate pedagogy, insufficient support for educators, inappropriate and unfair assessment procedures

Reading disabilities (RD) have a significant genetic basis and chromosomes 3p12-q13 and 15q15-21 have shown replicated linkage to RD or reading measures. This study evaluated two RD candidate genes within these regions: DYX1C1 on chromosome 15q21 and ROBO1 on chromosome 3p12. DYX1C1 was tested for association using a family-based analysis of two independent samples. No statistically significant association was observed between the 10 tested DYX1C1 single nucleotide polymorphisms (SNPs) and RD or any of the quantitative traits. A review and meta-analysis of the potentially functional SNPs at the -3G/A and 1249G/T positions did not find strong support for these alleles as risk alleles for RD. ROBO1 was also evaluated in this study using SNPs that previously showed association with memory and reading measures in a population-based sample. None of the SNPs showed significant association with RD or any of the quantitative traits after correction for multiple testing.

Reading disabilities (RD) have a significant genetic basis and chromosomes 3p12-q13 and 15q15-21 have shown replicated linkage to RD or reading measures. This study evaluated two RD candidate genes within these regions: DYX1C1 on chromosome 15q21 and ROBO1 on chromosome 3p12. DYX1C1 was tested for association using a family-based analysis of two independent samples. No statistically significant association was observed between the 10 tested DYX1C1 single nucleotide polymorphisms (SNPs) and RD or any of the quantitative traits. A review and meta-analysis of the potentially functional SNPs at the -3G/A and 1249G/T positions did not find strong support for these alleles as risk alleles for RD. ROBO1 was also evaluated in this study using SNPs that previously showed association with memory and reading measures in a population-based sample. None of the SNPs showed significant association with RD or any of the quantitative traits after correction for multiple testing.

The purpose of this study was to follow the development of children with reading disabilities only, reading disabilites and ADHD, ADHD only, and a comparison group from the ages of 3 to 18. Differences were examined on the following variables: (a) Antecedent variables- Reynell Developmental Language Scales, Temperament, and Family Adversity; (b) School-age variables- behavioral and academic self-concept ratings; and (c) Psychological adjustment variables at age 18- self-reports of delinquency. Children from the reading disabled groups exhibited receptive language deficits, were from families who during the early childhood years had less resources to cope with problem situations, exhibited difficult temperamental characteristics, and had negative academic self-concepts. Distinctions were also noted between a "pervasive" and "situational" presentation of behavioral problems. During late adolescence the reading disabled groups exhibited similar levels of delinquency as their non-disabled peers. The implications of this study and directions for future research are discussed.

The main purpose of the present dissertation was to dismember and reconstruct some aspects of the complex relationship between literacy development and self-concept. Two main principles were included in the general design of the longitudinal investigation. The first principle involved an increasing level of specificity in three steps where the starting point was an overall picture of 700 pupils' reading acquisition and self-concept. The second step was a more detailed analysis with the focus upon 80 pupils. The third step finally entailed intense case-oriented analyses of a few students. The second principle required both a description of the situation for pupils in general and a mapping of pupils with learning disabilities. A multiple-method strategy as a set of converging operations was used to capture the underlying structures in the large bulk of data from 9 years. The results indicated a weak but significant relationship between reading acquistion and self-concept with classroom achievement standard as a moderating factor. LISREL-analyses supported those hypotheses suggesting a reciprocal causality between self-concept and reading acquisition. The influence from performance to the self-concept of ability was shown to be much stronger than the influence from the self-concept of ability to performance. Furthermore, the best fitting models indicated that the influence from self-concept of ability is probably stronger on reading comprehension than on reading and spelling in general. The hypothesis of strategic behavior as a mediating factor between selt-concept and later reading and spelling performance was partially confirmed. Comparisons between two groups of pupils with approximately the same cognitive level, one with underachievement in reading and/or spelling and the other group without such problems, revealed that the former group had significant lower self-concept in grades 1-6. As a group these underachievers did not catch up in reading and spelling during the whole school-period. Attention and strategic behavior seemed to be critical factors distinguishing learning disabled pupils from normal achieving ones and unsuccessful underachievers from successfuI " underachievers ". In comparison with normal achieving pupils and with pupils who managed to overcome their early reading problems, pupils with persisting problems were shown to have a lower self-concept and more negative memories from school. At the end of the school-period, they had lower aspirations and expectations for the future and were less inclined to consider school subjects as important and also less inclined to use their reading ability to read books. Thus, self-concept, reading acquisition, aspiration and strategic behavior are connected, and this dissertation is an attempt to reveal the pattern of these relations. / digitalisering@umu