Investigates the symptoms of acquired surface dyslexia in Hebrew. Four acquired surface dyslexic adults were compared with eight normal second graders in terms of reading strategy. Homophones and homographs were a major source of difficulty for native Hebrew surface dyslexic readers; the normal second graders used a non-lexical strategy. (45…
Schattka, Kerstin I.; Radach, Ralph; Huber, Walter
Based on recent progress in theory and measurement techniques, the analysis of eye movements has become one of the major methodological tools in experimental reading research. Our work uses this approach to advance the understanding of impaired information processing in acquired central dyslexia of stroke patients with aphasia. Up to now there has…
Ellis, Andrew W.
Jorm's proposal (EJ 205 636) that developmental dyslexics resemble brain-damaged deep dyslexics is not grounded on firm evidence. Holmes' likening of developmental dyslexia to acquired surface dyslexia at least demonstrates clear similarity between the errors made by the two groups. (Author/CP)
Berninger, V W; Lester, K; Sohlberg, M M; Mateer, C
This paper deals with intervention strategies for developmental and acquired dyslexia. In Study 1 two alternative strategies for developmental surface dyslexia (dysfunctional connection between the whole word orthographic code and the phonetic or name code) were compared. In both the initial study and replication study, a modification of the selective reminding technique was superior to a traditional multisensory technique in beginning readers, presumably because it facilitated word finding or prelexical access to a phonetic code. In Study 2 an adolescent with acquired deep dyslexia (dysfunctional connection between letter and phonemic codes) who had had his angular gyrus (site of grapheme-phoneme correspondence) surgically removed, recovered reading function after a four-month phonemic analysis training program. Further research is needed to evaluate the efficacy of theory-based intervention strategies in children with developmental reading disorders unrelated to focal lesions and in adults with acquired reading disorders related to focal lesions. PMID:14589528
Raman, Ilhan; Weekes, Brendan S.
The Turkish script is characterised by completely transparent bidirectional mappings between orthography and phonology. To date, there has been no reported evidence of acquired dyslexia in Turkish speakers leading to the naive view that reading and writing problems in Turkish are probably rare. We examined the extent to which phonological…
Dalmás, J F; Dansilio, S
We report a single-case study of peripherally acquired dyslexia that meets the clinical criteria of "alexia without agraphia." The patient, AA, has a large infarct involving the left posterior cerebral artery. The most striking feature is a severe impairment in recognizing single visually presented letters that precludes explicit or implicit access to reading, even in a letter-by-letter fashion. AA can, however, differentiate letters from similar nonsense characters and digits, and he is also able to identify alphanumeric signs when the visual channel is bypassed (through somesthesic or kinesthesic presentation). Spelling tasks are also well performed. Since there is a breakdown in mapping a visually presented letter to its abstract graphemic representation, we propose the term "visuographemic alexia" for this kind of reading disorder. The pattern of deficits is interpreted following theoretical models previously developed in cognitive neuropsychology. An alexia for arabic numerals with preserved comprehension lends additional support for the crucial processing of different notational systems (e.g., phonographic vs logographic). More general perceptive disorders do not seem to account for these patterns; they are material-specific. Finally, we attempt to specify functional correlations with the implied neural networks. PMID:11023635
Vuković, Mile; Vuković, Irena; Miller, Nick
This study examined patterns of acquired dyslexia in Serbian aphasic speakers, comparing profiles of groups with Broca's versus Wernicke's aphasia. The study also looked at the relationship of reading and auditory comprehension and between reading comprehension and reading aloud in these groups. Participants were 20 people with Broca's and 20 with Wernicke's aphasia. They were asked to read aloud and to understand written material from the Serbian adaptation of the Boston Diagnostic Aphasia Examination. A Serbian Word Reading Aloud Test was also used. The people with Broca's aphasia achieved better results in reading aloud and in reading comprehension than those with Wernicke's aphasia. Those with Wernicke's aphasia showed significantly more semantic errors than those with Broca's aphasia who had significantly more morphological and phonological errors. From the data we inferred that lesion sites accorded with previous work on networks associated with Broca's and Wernicke's aphasia and with a posterior-anterior axis for reading processes centred on (left) parietal-temporal-frontal lobes. PMID:27135368
... Awards Enhancing Diversity Find People About NINDS NINDS Dyslexia Information Page Table of Contents (click to jump ... Organizations Related NINDS Publications and Information What is Dyslexia? Dyslexia is a brain-based type of learning ...
Vellutino, Frank R.
Examines previous hypotheses of the causes of dyslexia. Proposes that dyslexia results from a subtle language deficiency rather than from defects in the visual system. Discusses current theories and assesses instructional strategies for dyslexics. (ML)
It is stated that dyslexia is a disorder of auditory origin. The meaning of dyslexia is divided into the medical and educational aspects of the disease in an attempt to lead the teacher to emphasize hearing in education rather than merely sight. The role of the teacher, doctor, and psychologist in the history of dyslexia is discussed. In dealing…
Riley, Ellyn Anne
Individuals with acquired phonological dyslexia experience difficulty associating written letters with their corresponding sounds, especially in pseudowords. Several studies have attempted to improve reading in this population by training letter-to-sound correspondence, general phonological skills, or a combination of these approaches; however,…
Böhm, P; Diéguez-Vide, F; Peña-Casanova, J; Tainturier, M J; Lecours, A R
The present paper discusses the different clinical manifestations of acquired disorders of reading and writing from a neurocognitive viewpoint. Based on a specific functional architecture of reading and writing--a cognitive model; presented as well--the different syndromes of acquired dyslexias and dysgraphias, that have been described in the specialized literature during the last 25 years, will be reviewed. The different pathologies are distributed along three different functional axes: a plurimodal component, including the semantic system, for the description of peripheric disorders of reading and writing; a lexical block which is justified by the findings in patients with surface dyslexia/dysgraphia; and a third, sublexical component, in order to illustrate the different functional impairments in phonological dyslexia/dysgraphia. Following the description of syndromes due to selective "functional lesions", we discuss deep dyslexia/dysgraphia, a syndrome due to multiple functional lesions. All of the syndromes will be justified and discussed with respect to the different components of the functional architecture presented and are based on cases of the literature and personal observations. Concluding remarks will evaluate the new insights gained by the presented functional arquitecture in relation to other cognitive models for the analysis of reading aloud and writing to dictation of single words. PMID:10769534
... Medical Words En Español What Other Kids Are Reading Back-to-School Butterflies? Read This Chloe & Nurb ... can learn to read and spell. How Does Reading Happen? To understand dyslexia, it helps to understand ...
Ablinger, Irene; von Heyden, Kerstin; Vorstius, Christian; Halm, Katja; Huber, Walter; Radach, Ralph
Due to their brain damage, aphasic patients with acquired dyslexia often rely to a greater extent on lexical or segmental reading procedures. Thus, therapy intervention is mostly targeted on the more impaired reading strategy. In the present work we introduce a novel therapy approach based on real-time measurement of patients' eye movements as they attempt to read words. More specifically, an eye movement contingent technique of stepwise letter de-masking was used to support sequential reading, whereas fixation-dependent initial masking of non-central letters stimulated a lexical (parallel) reading strategy. Four lexical and four segmental readers with acquired central dyslexia received our intensive reading intervention. All participants showed remarkable improvements as evident in reduced total reading time, a reduced number of fixations per word and improved reading accuracy. Both types of intervention led to item-specific training effects in all subjects. A generalisation to untrained items was only found in segmental readers after the lexical training. Eye movement analyses were also used to compare word processing before and after therapy, indicating that all patients, with one exclusion, maintained their preferred reading strategy. However, in several cases the balance between sequential and lexical processing became less extreme, indicating a more effective individual interplay of both word processing routes. PMID:24813563
Hricová, Marianna; Weekes, Brendan Stuart
The first reports of phonological, surface and deep dyslexia come from orthographies containing quasi-regular mappings between orthography and phonology including English and French. Slovakian is a language with a relatively transparent orthography and hence a mostly regular script. The aim of this study was to investigate impaired oral reading in Slovakian. A novel diagnostic procedure was devised to determine whether disorders of Slovakian reading resemble characteristics in other languages. Slovakian speaking aphasics showed symptoms similar to phonological dyslexia and deep dyslexia in English and French, but there was no evidence of surface dyslexia. The findings are discussed in terms of the orthographic depth hypothesis. PMID:22713384
Habib, Michel; Giraud, Kimberly
Developmental dyslexia (DD) is a specific and persistent disability affecting the acquisition of written language. Prevalence is estimated to be between 5% and 17% of school-aged children; it therefore represents a major public health issue. Neurological in origin, its causes are unknown, although there is a clear genetic component. Diagnosis rests upon the use of standardized tests and tools to assess reading and spelling, as well as phonological skills. The importance of early diagnosis cannot be overemphasized and much current research is focusing on screening and prediction, particularly through use of objective imaging techniques (e.g., EEG/MEG), which have implicated cortical abnormalities in central auditory processing (Giraud et al., 2005, 2008). Remediation should be intensive, begin as early as possible, and be tailored to the individual. Phonics based treatments are most effective and several variants, incorporating temporal auditory, articulatory, or multisensory training exercises, have been developed or proposed. Clinical improvements in phonological skills and reading with such treatments have been shown to correlate with changes in the brains of dyslexic children in several functional imaging studies. PMID:23622168
Gvion, Aviah; Friedmann, Naama
Lexical retrieval and reading aloud are often viewed as two separate processes. However, they are not completely separate-they share components. This study assessed the effect of an impairment in a shared component, the phonological output lexicon, on lexical retrieval and on reading aloud. Because the phonological output lexicon is part of the lexical route for reading, individuals with an impairment in this lexicon may be forced to read aloud via the sublexical route and therefore show a reading pattern that is typical of surface dyslexia. To examine the effect of phonological output lexicon deficit on reading, we tested the reading of 16 Hebrew-speaking individuals with phonological output lexicon anomia, eight with acquired anomia following brain damage and eight with developmental anomia. We established that they had a phonological output lexicon deficit according to the types of errors and the effects on their naming in a picture naming task, and excluded other deficit loci in the lexical retrieval process according to a line of tests assessing their picture and word comprehension, word and non-word repetition, and phonological working memory. After we have established that the participants have a phonological output lexicon deficit, we tested their reading. To assess their reading and type of reading impairment, we tested their reading aloud, lexical decision, and written word comprehension. We found that all of the participants with phonological output lexicon impairment showed, in addition to anomia, also the typical surface dyslexia errors in reading aloud of irregular words, words with ambiguous conversion to phonemes, and potentiophones (words like "now" that, when read via the sublexical route, can be sounded out as another word, "know"). Importantly, the participants performed normally on pseudohomophone lexical decision and on homophone/potentiophone reading comprehension, indicating spared orthographic input lexicon and spared access to it and from
Gvion, Aviah; Friedmann, Naama
Lexical retrieval and reading aloud are often viewed as two separate processes. However, they are not completely separate—they share components. This study assessed the effect of an impairment in a shared component, the phonological output lexicon, on lexical retrieval and on reading aloud. Because the phonological output lexicon is part of the lexical route for reading, individuals with an impairment in this lexicon may be forced to read aloud via the sublexical route and therefore show a reading pattern that is typical of surface dyslexia. To examine the effect of phonological output lexicon deficit on reading, we tested the reading of 16 Hebrew-speaking individuals with phonological output lexicon anomia, eight with acquired anomia following brain damage and eight with developmental anomia. We established that they had a phonological output lexicon deficit according to the types of errors and the effects on their naming in a picture naming task, and excluded other deficit loci in the lexical retrieval process according to a line of tests assessing their picture and word comprehension, word and non-word repetition, and phonological working memory. After we have established that the participants have a phonological output lexicon deficit, we tested their reading. To assess their reading and type of reading impairment, we tested their reading aloud, lexical decision, and written word comprehension. We found that all of the participants with phonological output lexicon impairment showed, in addition to anomia, also the typical surface dyslexia errors in reading aloud of irregular words, words with ambiguous conversion to phonemes, and potentiophones (words like “now” that, when read via the sublexical route, can be sounded out as another word, “know”). Importantly, the participants performed normally on pseudohomophone lexical decision and on homophone/potentiophone reading comprehension, indicating spared orthographic input lexicon and spared access to it
Binder, Jeffrey R; Pillay, Sara B; Humphries, Colin J; Gross, William L; Graves, William W; Book, Diane S
Patients with surface dyslexia have disproportionate difficulty pronouncing irregularly spelled words (e.g. pint), suggesting impaired use of lexical-semantic information to mediate phonological retrieval. Patients with this deficit also make characteristic 'regularization' errors, in which an irregularly spelled word is mispronounced by incorrect application of regular spelling-sound correspondences (e.g. reading plaid as 'played'), indicating over-reliance on sublexical grapheme-phoneme correspondences. We examined the neuroanatomical correlates of this specific error type in 45 patients with left hemisphere chronic stroke. Voxel-based lesion-symptom mapping showed a strong positive relationship between the rate of regularization errors and damage to the posterior half of the left middle temporal gyrus. Semantic deficits on tests of single-word comprehension were generally mild, and these deficits were not correlated with the rate of regularization errors. Furthermore, the deep occipital-temporal white matter locus associated with these mild semantic deficits was distinct from the lesion site associated with regularization errors. Thus, in contrast to patients with surface dyslexia and semantic impairment from anterior temporal lobe degeneration, surface errors in our patients were not related to a semantic deficit. We propose that these patients have an inability to link intact semantic representations with phonological representations. The data provide novel evidence for a post-semantic mechanism mediating the production of surface errors, and suggest that the posterior middle temporal gyrus may compute an intermediate representation linking semantics with phonology. PMID:26966139
Eden, Guinevere F.; Wood, Frank B.; Stein, John F.
A study involving 93 children (ages 10-12), 295 with poor reading skills, found many children with dyslexia and some garden-variety poor readers showed significant left neglect on the Clock Drawing Test. In poor readers with dyslexia, spatial construction deficits were observed like those of parents with acquired right-hemisphere lesions.…
Wagner, Rudolph F.
Theoretical, diagnostic, and remedial issues related to polyglot dyslexia (i.e., difficulties in reading experienced in both languages spoken by bilinguals) are considered. Theoretical causes of dyslexia, research done with neuropsychological and neurolinguistic aspects of bilingualism, the literature on polyglot aphasia, and theoretical concerns…
Peterson, Robin L; Pennington, Bruce F
This review uses a levels-of-analysis framework to summarize the current understanding of developmental dyslexia's etiology, brain bases, neuropsychology, and social context. Dyslexia is caused by multiple genetic and environmental risk factors as well as their interplay. Several candidate genes have been identified in the past decade. At the brain level, dyslexia is associated with aberrant structure and function, particularly in left hemisphere reading/language networks. The neurocognitive influences on dyslexia are also multifactorial and involve phonological processing deficits as well as weaknesses in other oral language skills and processing speed. We address contextual issues such as how dyslexia manifests across languages and social classes as well as what treatments are best supported. Throughout the review, we highlight exciting new research that cuts across levels of analysis. Such work promises eventually to provide a comprehensive explanation of the disorder as well as its prevention and remediation. PMID:25594880
Virasoro, M. A.
We show that certain specific correlations in the probability of errors observed in dyslexic patients that are normally explained by introducing additional complexity in the model for the reading process are typical of any Neural Network system that has learned to deal with a quasiregular environment. On the other hand we show that in Neural Networks the more regular behavior does not become naturally the default behavior.
Peterson, Robin L; Pennington, Bruce F
Dyslexia is a neurodevelopmental disorder that is characterised by slow and inaccurate word recognition. Dyslexia has been reported in every culture studied, and mounting evidence draws attention to cross-linguistic similarity in its neurobiological and neurocognitive bases. Much progress has been made across research specialties spanning the behavioural, neuropsychological, neurobiological, and causal levels of analysis in the past 5 years. From a neuropsychological perspective, the phonological theory remains the most compelling, although phonological problems also interact with other cognitive risk factors. Work confirms that, neurobiologically, dyslexia is characterised by dysfunction of the normal left hemisphere language network and also implicates abnormal white matter development. Studies accounting for reading experience demonstrate that many recorded neural differences show causes rather than effects of dyslexia. Six predisposing candidate genes have been identified, and evidence shows gene by environment interaction. PMID:22513218
Démonet, Jean-François; Taylor, Margot J; Chaix, Yves
Developmental dyslexia, or specific reading disability, is a disorder in which children with normal intelligence and sensory abilities show learning deficits for reading. Substantial evidence has established its biological origin and the preponderance of phonological disorders even though important phenotypic variability and comorbidity have been recorded. Diverse theories have been proposed to account for the cognitive and neurological aspects of dyslexia. Findings of genetic studies show that different loci affect specific reading disability although a direct relation has not been established between symptoms and a given genomic locus. In both children and adults with dyslexia, results of neuroimaging studies suggest defective activity and abnormal connectivity between regions crucial for language functions--eg, the left fusiform gyrus for reading--and changes in brain activity associated with performance improvement after various remedial interventions. PMID:15121410
Tunmer, William; Greaney, Keith
In 2007, the New Zealand Ministry of Education formally recognized the condition of dyslexia for the first time and has subsequently developed a working definition of the condition. The aim of this article is to draw on contemporary theory and research on reading development, reading difficulties, and reading intervention to describe what the…
The investigation reported in this volume attempts to clarify some issues relating to the existence, nature, and causes of specific dyslexia. Based on an extended study of 98 boys of at least average intelligence with severe reading and spelling problems, the report provides detailed data relating to their developmental and perinatal histories,…
Ansara, Alice, Ed.
This bulletin is published annually in the interest of children with learning disabilities, language disabilities, or dyslexia. The 22 articles discuss the following topics: current issues in dyslexia, language disorders, subgroups in dyslexia, specificity and parameters in defining dyslexia, strategies for recognition and management of reading…
Shannon, Albert J.
The article reviews proposed causes and observable symptoms that characterize dyslexia, concluding that individualized analysis and specialized treatments are required and that, until an operational definition can be agreed upon, use of the label "dyslexia" is counterproductive. (DB)
Moll, Kristina; Loff, Ariana; Snowling, Margaret J.
The study investigated cognitive deficits associated with dyslexia and familial risk of dyslexia (endophenotypes) by comparing children from families with and without a history of dyslexia. Eighty-eight school-aged children were assessed on measures of phonology, language and rapid automatized naming. A series of regression analyses with family…
This book addresses the issue of living with dyslexia, illuminating the problems using first-person accounts and personal histories of child and adult dyslexics, even entire dyslexic families. Dubbed the "middle class disease" by some and a "specific learning disability" by others, dyslexia affects one in 25 persons. Although dyslexia can involve…
Hennigh, Kathleen Anne
Pointing out that the label of dyslexia carries an acute stigma of mental incompetence (and the researcher/author is herself dyslexic), this booklet intends to provide educators and parents with a frame of reference regarding the topic of dyslexia. Defining dyslexia broadly as "characterized by a consistent difficulty with processing phonological…
National Inst. of Child Health and Human Development (NIH), Bethesda, MD.
This brochure presents current knowledge and theories regarding the causes and treatment of dyslexia. Psychological, biological and educational factors thought to contribute to dyslexia are outlined, as are common approaches to treatment and long-term prospects for individuals with dyslexia. Efforts by the National Institute of Child Health and…
Schneps, Matthew H.; Greenhill, L. J.; Rose, L. T.
Dyslexia is a hereditary neurological disability that impairs reading. It is believed that anywhere from 5% to 20% of all people in the US may have dyslexia to a greater or lesser degree. Though dyslexia is common, it is a "silent disability" in the sense that it is not easy to tell which individuals suffer from dyslexia and which do not. There is a substantial body of evidence to suggest that people with dyslexia tend to do well in science. For example, Baruj Benacerraf, a Nobel laureate in medicine, is among those whose impairments have been documented and studied. Given that dyslexia was not diagnosed in schools prior to the late 1970's, many established science researchers may have dyslexia and be unaware of their impairment. Therefore, it would not be surprising to find that substantial numbers of scientists working in the fields of astronomy and astrophysics have dyslexia, and yet be unaware of the effects this disability has had on their research. A recently proposed theory by the authors suggests that there may be specific neurological reasons why those with dyslexia may be predisposed to science, and predicts that dyslexia may be associated with enhanced abilities for certain types of visual processing, with special implications for image processing. Our study, funded by the NSF, investigates this hypothesis in the context of astronomy and astrophysics. We expect this work will uncover and document challenges faced by scientists with dyslexia, but perhaps more importantly, lead to an understanding of the strengths these scientists bring to research. The program will serve as a clearing-house of information for scientists and students with dyslexia, and begin to provide mentoring for young people with dyslexia interested in astronomy. Scientists who have reason to believe they may have dyslexia are encouraged to contact the authors.
Norton, Elizabeth S; Beach, Sara D; Gabrieli, John D E
Dyslexia is one of the most common learning disabilities, yet its brain basis and core causes are not yet fully understood. Neuroimaging methods, including structural and functional magnetic resonance imaging, diffusion tensor imaging, and electrophysiology, have significantly contributed to knowledge about the neurobiology of dyslexia. Recent studies have discovered brain differences before formal instruction that likely encourage or discourage learning to read effectively, distinguished between brain differences that likely reflect the etiology of dyslexia versus brain differences that are the consequences of variation in reading experience, and identified distinct neural networks associated with specific psychological factors that are associated with dyslexia. PMID:25290881
Temple, C M
Although Hinshelwood (10-15), at the turn of the century, was interested in both analysis of individual cases and comparisons between acquired and developmental dyslexia, the most widespread approach to the developmental dyslexias has been the investigation of large groups of dyslexics in comparison to normal readers on a variety of tests. These studies ignore the heterogeneity of the disorder. In contrast, progress has been made in the investigation of acquired disorders of reading by conducting individual psycholinguistic analyses of reading difficulties and utilizing input from cognitive psychology to construct explanatory models and theories. Two of the disorders described and elucidated by this approach are acquired surface dyslexia, in which there is an impairment in whole word recognition and overreliance on sounding out words to obtain their pronunciation and meaning, and acquired phonological dyslexia, in which whole word recognition is good but sounding out of words and nonwords is poor. This approach has recently been used with cases of developmental dyslexia. This chapter compares and contrasts the pattern of performance of different dyslexic children when investigated in this way. Two of the children described are developmental phonological dyslexics; one is a developmental surface dyslexic. The developmental phonological dyslexics are poorer at reading words than non-words; the developmental surface dyslexic performs equally well on both. The developmental surface dyslexic is significantly influenced by spelling-to-sound regularity; the developmental phonological dyslexics are unaffected by this linguistic dimension. The developmental surface dyslexic makes more neologistic responses than the developmental phonological dyslexics, and also makes more valid errors. The developmental phonological dyslexics make derivational, pseudoderivational, and visuosemantic errors. Both groups make visual errors. The developmental phonological dyslexics are
Elbeheri, Gad; Everatt, John; Reid, Gavin; Mannai, Haya al
Despite advancements in empirical studies of developmental dyslexia, progress on methods of dyslexia assessment have been hampered by ongoing debate concerning diverse issues such as the role and validity of IQ in the assessment process, labelling and definitions (Miles, 1994; Stanovich, 1991, 1992). With the emergence of cross-linguistic studies…
National Inst. of Child Health and Human Development (NIH), Bethesda, MD.
Developmental dyslexia is a specific learning disability characterized by difficulty in learning to read. Some dyslexics also may have difficulty learning to write, to spell, and to speak or work with numbers. Some researchers estimate that as many as 15 percent of American students may be classified as dyslexic. Children with dyslexia are not all…
Bartlett, Diana; Moody, Sylvia
This book is designed for both adults with dyslexia and for professionals concerned with helping them, such as psychologists, tutors, therapists, researchers, disability advisors, and welfare officers. It also offers advice to employers on how to help staff with dyslexia. The text covers the nature of dyslexic difficulties and their effects, both…
Hoyles, Asher; Hoyles, Martin
This article begins with a definition of dyslexia as genetic, involving language processing and phonological awareness. It goes beyond reading and writing difficulties to include, for example, sequencing, orientation, short-term memory, speed, circumlocution, organisational skills, visual thinking, self-esteem and anger. Dyslexia, though…
Siegel, Linda S
Dyslexia, or a reading disability, occurs when an individual has significant difficulty with speed and accuracy of word decoding. Comprehension of text and spelling are also affected. The diagnosis of dyslexia involves the use of reading tests, but the continuum of reading performance means that any cutoff point is arbitrary. The IQ score does not play a role in the diagnosis of dyslexia. The cognitive difficulties of dyslexics include problems with speech perception, recognizing and manipulating the basic sounds in a language, language memory, and learning the sounds of letters. Dyslexia is a neurological condition with a genetic basis. There are abnormalities in the brains of dyslexic individuals. There are also differences in the electrophysiological and structural characteristics of the brains of dyslexics. Physicians play a particularly important role in recognizing children who are at risk for dyslexia and helping their parents obtain the proper assessment. PMID:19030329
Zelcer, Michal; Goldman, Ran D.
Abstract Question In light of the increase in the number of school-aged children diagnosed with dyslexia, what is the role of omega-3 supplements in the management of this condition? Answer Dyslexia is the most common learning disability and is known to have multifactorial causes. Recent evidence suggests that there is a connection between defects in highly unsaturated fatty acid metabolism and neurodevelopmental disorders such as dyslexia. While the benefit of omega-3 supplementation for children with dyslexia has been studied, evidence remains limited. Unified diagnostic criteria for dyslexia, objective measures of fatty acid deficiency, and close monitoring of dietary intake are some of the factors that would improve the quality of research in the field. PMID:26371100
Fostick, Leah; Bar-El, Sharona; Ram-Tsur, Ronit
Dyslexia is a neuro-cognitive disorder with a strong genetic basis, characterized by a difficulty in acquiring reading skills. Several hypotheses have been suggested in an attempt to explain the origin of dyslexia, among which some have suggested that dyslexic readers might have a deficit in auditory temporal processing, while others hypothesized…
A company is promoting behavioral exercises as a cure for dyslexia. Scientists worry that evaluation of the program is compromised by design flaws and conflicts of interest and that responses to critics restrict academic freedom. PMID:17259957
Peterson, Robin L.; Pennington, Bruce F.
Summary Dyslexia is a neurodevelopmental disorder that is characterized by slow and inaccurate word recognition. Dyslexia has been found in every culture studied, and mounting evidence underscores cross-linguistic similarity in its neurobiological and neurocognitive bases. There has been considerable progress across levels of analysis in the last five years. At a neuropsychological level, the phonological theory remains the most compelling, though it is increasingly clear that phonological problems interact with other cognitive risk factors. At a neurobiological level, recent research confirms that dyslexia is characterized by dysfunction of the normal left hemisphere language network and also implicates abnormal white matter development. Studies accounting for reading experience demonstrate that many observed neural differences reflect causes rather than effects of dyslexia. At an etiologic risk level, six candidate genes have been identified, and there is evidence for gene by environment interaction. This review includes a focus on these and other recent developments. PMID:22513218
... a bigger reading problem and a drop in self-esteem. So it's important to recognize symptoms early in ... and falling further behind their classmates. And their self-esteem may take a beating. Treating Dyslexia Fortunately, with ...
Pacheco, Andreia; Reis, Alexandra; Araújo, Susana; Inácio, Filomena; Petersson, Karl Magnus; Faísca, Luís
Recent studies have emphasized that developmental dyslexia is a multiple-deficit disorder, in contrast to the traditional single-deficit view. In this context, cognitive profiling of children with dyslexia may be a relevant contribution to this unresolved discussion. The aim of this study was to profile 36 Portuguese children with dyslexia from…
Thompson, Paul A.; Hulme, Charles; Nash, Hannah M.; Gooch, Debbie; Hayiou-Thomas, Emma; Snowling, Margaret J.
Background: Causal theories of dyslexia suggest that it is a heritable disorder, which is the outcome of multiple risk factors. However, whether early screening for dyslexia is viable is not yet known. Methods: The study followed children at high risk of dyslexia from preschool through the early primary years assessing them from age 3 years and 6…
Harrie, Roger P.; Weller, Carol
The digest focuses on the nature of dyslexia and its characteristics. An initial section notes the variations in definitions as a function of the discipline. Diagnosis of dyslexia is said to isolate the specific difficulties associated with the problem and to suggest appropriate educational intervention. Typical characteristics of dyslexia are…
Sawyer, Diane J.
This article provides a brief overview of the various areas of research that have served to clarify the condition of dyslexia. Using topics and content appearing in A. L. Benton and D. Pearl's (1978) text, Dyslexia: An Appraisal of Current Knowledge, as the point of departure, evolution of the definitions of dyslexia is traced to the current and…
Lukov, Limor; Friedmann, Naama; Shalev, Lilach; Khentov-Kraus, Lilach; Shalev, Nir; Lorber, Rakefet; Guggenheim, Revital
We examine whether attention deficits underlie developmental dyslexia, or certain types of dyslexia, by presenting double dissociations between the two. We took into account the existence of distinct types of dyslexia and of attention deficits, and focused on dyslexias that may be thought to have an attentional basis: letter position dyslexia (LPD), in which letters migrate within words, attentional dyslexia (AD), in which letters migrate between words, neglect dyslexia, in which letters on one side of the word are omitted or substituted, and surface dyslexia, in which words are read via the sublexical route. We tested 110 children and adults with developmental dyslexia and/or attention deficits, using extensive batteries of reading and attention. For each participant, the existence of dyslexia and the dyslexia type were tested using reading tests that included stimuli sensitive to the various dyslexia types. Attention deficit and its type was established through attention tasks assessing sustained, selective, orienting, and executive attention functioning. Using this procedure, we identified 55 participants who showed a double dissociation between reading and attention: 28 had dyslexia with normal attention and 27 had attention deficits with normal reading. Importantly, each dyslexia with suspected attentional basis dissociated from attention: we found 21 individuals with LPD, 13 AD, 2 neglect dyslexia, and 12 surface dyslexia without attention deficits. Other dyslexia types (vowel dyslexia, phonological dyslexia, visual dyslexia) also dissociated from attention deficits. Examination of 55 additional individuals with both a specific dyslexia and a certain attention deficit found no attention function that was consistently linked with any dyslexia type. Specifically, LPD and AD dissociated from selective attention, neglect dyslexia dissociated from orienting, and surface dyslexia dissociated from sustained and executive attention. These results indicate that
Colangelo, Annette; Buchanan, Lori; Westbury, Chris
Deep dyslexia is an acquired reading disorder that involves the production of semantic errors and the inability to read aloud nonwords successfully. Several explanations for this reading impairment posit multiple loci of damage to account for the various error types produced in deep dyslexia. In contrast, the failure of inhibition hypothesis…
Nicolson, Roderick I
It is all too easy, in everyday interactions in dyslexia, to see the interactions in a semi-adversarial fashion--parents competing to get more support for children, researchers competing to get more support for their theories, schools trying to get more money for their programmes. Such a set of analyses may be described as 'zero-sum'. If one party gains, the other one loses. If, by contrast, one views the dyslexia community as a complex, inter-dependent 'ecosystem', a much more positive view emerges. It becomes clear that there are solutions for the system as a whole that are in a sense optimal for the system as a whole, solutions that are 'win-win', that is, all parties gain and none lose. In this article I develop this concept of the 'dyslexia ecosystem', and outline targets that would lead to progress for the ecosystem as a whole. PMID:12067187
Tamboer, Peter; Vorst, Harrie C M; Oort, Frans J
Two subtypes of dyslexia (phonological, visual) have been under debate in various studies. However, the number of symptoms of dyslexia described in the literature exceeds the number of subtypes, and underlying relations remain unclear. We investigated underlying cognitive features of dyslexia with exploratory and confirmatory factor analyses. A sample of 446 students (63 with dyslexia) completed a large test battery and a large questionnaire. Five factors were found in both the test battery and the questionnaire. These 10 factors loaded on 5 latent factors (spelling, phonology, short-term memory, rhyme/confusion, and whole-word processing/complexity), which explained 60% of total variance. Three analyses supported the validity of these factors. A confirmatory factor analysis fit with a solution of five factors (RMSEA = .03). Those with dyslexia differed from those without dyslexia on all factors. A combination of five factors provided reliable predictions of dyslexia and nondyslexia (accuracy >90%). We also looked for factorial deficits on an individual level to construct subtypes of dyslexia, but found varying profiles. We concluded that a multiple cognitive deficit model of dyslexia is supported, whereas the existence of subtypes remains unclear. We discussed the results in relation to advanced compensation strategies of students, measures of intelligence, and various correlations within groups of those with and without dyslexia. PMID:25398549
Granschow, Lenore; And Others
Case studies are presented of musicians with dyslexia who experienced difficulties in the study of musical notation. The studies focus on their educational histories, musical weaknesses and strengths, and successful compensatory strategies. Suggestions are offered on using multisensory approaches to teach musical notation. (Author/JDD)
The main objective of this book is to explain the thinking that is involved in working out a systematic scheme of the variables related to dyslexia. The contents of the book include "Origins of the Approach,""Some Principles of Instruction"; "Verbal Behavior"; "Our Ideas about Language"; "Left and Right"; "The Biology of the Book"; "Exploring…
Nicolson, R. I.; Fawcett, A. J.; Brookes, R. L.; Needle, J.
Three major "neural systems", specialized for different types of information processing, are the sensory, declarative, and procedural systems. It has been proposed ("Trends Neurosci.",30(4), 135-141) that dyslexia may be attributable to impaired function in the procedural system together with intact declarative function. We provide a brief…
Elliott, Julian G.; Gibbs, Simon
In this paper we argue that attempts to distinguish between categories of "dyslexia" and "poor reader" or "reading disabled" are scientifically unsupportable, arbitrary and thus potentially discriminatory. We do not seek to veto scientific curiosity in examining underlying factors in reading disability, for seeking greater understanding of the…
Hickman, Richard; Brens, Madeleine
This article presents exploratory research examining the strategies employed by art teachers who identify as dyslexic. The study originated out of the personal interest of the researchers better to understand the strategies for learning used by teachers with dyslexia and the potential influence it has on their pedagogy. The question that this…
This book explores how primary school children with dyslexia or dyspraxia and difficulty in math can learn math and provides practical support and detailed teaching suggestions. It considers cognitive features that underlie difficulty with mathematics generally or with specific aspects of mathematics. It outlines the ways in which children usually…
Williams, Joan A.; Lynch, Sharon A.
Though the term dyslexia is familiar to the American public and is frequently seen in the media, it often is misunderstood, even in the educational setting. The International Dyslexia Association established the following definition of dyslexia: Dyslexia is a specific learning disability that is neurological in origin. It is characterized by…
This book explains the nature of dyslexia, enumerates the various forms of treatment, and considers the many challenges faced by those living with this condition. The book defines dyslexia as a brain-based disorder that causes problems for people when they are reading, writing, spelling, doing math computation, speaking, or even listening to…
Hynd, George W.; Hynd, Cynthia R.
Reviews attempts to adequately define dyslexia with a focus on recent efforts at developing a nosology of dyslexia and discusses the neurological basis of reading and severe reading failure with an emphasis on validating evidence provided through brain-mapping procedures and postmortem studies. (HOD)
Elliott, Julian G.
In this article, the author argues that there are so many different understandings and conceptualizations about what dyslexia is, or is not, that the term has become almost meaningless. The questioning of the value of the dyslexia concept turned into media headlines in the UK. The author accounts three key questions surrounding the debate about…
Winters, Roberta L.; And Others
Visual persistence was investigated in adults with and without dyslexia in order to determine whether dyslexic adults demonstrate problems similar to those found in childhood dyslexia. Results showed that sensitivity of dyslexic adults was impaired when parts of a test stimulus were presented to adjacent retinal areas, suggesting that under…
This article discusses dyslexia (one of the many complex issues that affects students) and the ways to tackle it appropriately. Dyslexia is described as a syndrome in which a person's reading and/or writing ability is significantly lower than that which would be predicted by his or her general level of intelligence. People are diagnosed as…
Ganschow, L; Lloyd-Jones, J; Miles, T R
The authors examine the difficulties experienced by dyslexic musicians in the formalized study of music, in particular, musical notation. They describe case studies from the literature and from personal interviews they conducted with musicians about their educational histories, musical weaknesses and strengths, and successful compensatory strategies. The authors make instructional suggestions for educators and musicians with dyslexia on how to use multisensory approaches to teach musical notation. PMID:24234052
Ozernov-Palchik, Ola; Gaab, Nadine
Developmental dyslexia is an unexplained inability to acquire accurate or fluent reading that affects approximately 5-17% of children. Dyslexia is associated with structural and functional alterations in various brain regions that support reading. Neuroimaging studies in infants and pre-reading children suggest that these alterations predate reading instruction and reading failure, supporting the hypothesis that variant function in dyslexia susceptibility genes lead to atypical neural migration and/or axonal growth during early, most likely in utero, brain development. Yet, dyslexia is typically not diagnosed until a child has failed to learn to read as expected (usually in second grade or later). There is emerging evidence that neuroimaging measures, when combined with key behavioral measures, can enhance the accuracy of identification of dyslexia risk in pre-reading children but its sensitivity, specificity, and cost-efficiency is still unclear. Early identification of dyslexia risk carries important implications for dyslexia remediation and the amelioration of the psychosocial consequences commonly associated with reading failure. WIREs Cogn Sci 2016, 7:156-176. doi: 10.1002/wcs.1383 For further resources related to this article, please visit the WIREs website. PMID:26836227
Nicolson, R I; Fawcett, A J; Brookes, R L; Needle, J
Three major 'neural systems', specialized for different types of information processing, are the sensory, declarative, and procedural systems. It has been proposed (Trends Neurosci., 30(4), 135-141) that dyslexia may be attributable to impaired function in the procedural system together with intact declarative function. We provide a brief overview of the increasing evidence relating to the hypothesis, noting that the framework involves two main claims: first that 'neural systems' provides a productive level of description avoiding the underspecificity of cognitive descriptions and the overspecificity of brain structural accounts; and second that a distinctive feature of procedural learning is its extended time course, covering from minutes to months. In this article, we focus on the second claim. Three studies-speeded single word reading, long-term response learning, and overnight skill consolidation-are reviewed which together provide clear evidence of difficulties in procedural learning for individuals with dyslexia, even when the tasks are outside the literacy domain. The educational implications of the results are then discussed, and in particular the potential difficulties that impaired overnight procedural consolidation would entail. It is proposed that response to intervention could be better predicted if diagnostic tests on the different forms of learning were first undertaken. PMID:20680991
Thompson, Paul A; Hulme, Charles; Nash, Hannah M; Gooch, Debbie; Hayiou-Thomas, Emma; Snowling, Margaret J
Background Causal theories of dyslexia suggest that it is a heritable disorder, which is the outcome of multiple risk factors. However, whether early screening for dyslexia is viable is not yet known. Methods The study followed children at high risk of dyslexia from preschool through the early primary years assessing them from age 3 years and 6 months (T1) at approximately annual intervals on tasks tapping cognitive, language, and executive-motor skills. The children were recruited to three groups: children at family risk of dyslexia, children with concerns regarding speech, and language development at 3;06 years and controls considered to be typically developing. At 8 years, children were classified as ‘dyslexic’ or not. Logistic regression models were used to predict the individual risk of dyslexia and to investigate how risk factors accumulate to predict poor literacy outcomes. Results Family-risk status was a stronger predictor of dyslexia at 8 years than low language in preschool. Additional predictors in the preschool years include letter knowledge, phonological awareness, rapid automatized naming, and executive skills. At the time of school entry, language skills become significant predictors, and motor skills add a small but significant increase to the prediction probability. We present classification accuracy using different probability cutoffs for logistic regression models and ROC curves to highlight the accumulation of risk factors at the individual level. Conclusions Dyslexia is the outcome of multiple risk factors and children with language difficulties at school entry are at high risk. Family history of dyslexia is a predictor of literacy outcome from the preschool years. However, screening does not reach an acceptable clinical level until close to school entry when letter knowledge, phonological awareness, and RAN, rather than family risk, together provide good sensitivity and specificity as a screening battery. PMID:25832320
Buckley, Robert E.
The article examines the neurological basis for hyperactivity/distraction and dyslexia. Overlapping symptoms are listed, nutritional and organic basis for hyperkinesis considered, and visual and motoric factors in dyslexia discussed. (CL)
Suárez-Coalla, Paz; Cuetos, Fernando
Recent studies show that dyslexia persists into adulthood, even in highly educated and well-read people. The main characteristic that adults with dyslexia present is a low speed when reading. In Spanish, a shallow orthographic system, no studies about adults with dyslexia are available; and it is possible that the consistency of the orthographic…
THE THEORY OF DEVELOPMENTAL DYSLEXIA IS CONTRASTED WITH THE THEORY OF DEVELOPMENTAL IMMATURITY TO EXPLAIN EXTREME READING RETARDATION. DYSLEXIA IS DEFINED AS AN ORGANICALLY BASED READING DISABILITY WHICH IS DETERMINED INDIRECTLY SINCE NO ANATOMIC LESION, CHROMOSOME, OR GENE HAS YET BEEN FOUND RESPONSIBLE. DYSLEXIA IS USUALLY DEDUCED FROM (1)…
Groff, Charlotte V.
A literature review was conducted to determine the meaning, symptoms, causes, and treatment of dyslexia. The review revealed that dyslexia simply means "distorted words," and is the inability to read either phonetically or visually. Among the symptoms of dyslexia disclosed by the review are motion sickness, retardation in reading of from 6 months…
Of all human maladies which account for learning disabilities among young and old alike, few remain as poorly understood and inconclusively defined as dyslexia. The general public perceives dyslexia to be a reading problem; some psychologists believe that dyslexia can stem from a low socio-economic status; educators see the term as involving…
Dahle, Anne Elisabeth; Knivsberg, Ann-Mari; Andreassen, Anne Brit
A small group of children and young adolescent with dyslexia has severely impaired reading skills despite prolonged special education. These are the students in focus. In dyslexia, problem behaviour, internalised as well as externalised, has previously been reported, so also for the participants with dyslexia in this study. The aim of the present…
Riccio, Cynthia A.; Hynd, George W.
Research findings from autopsy studies, neuroimaging, functional imaging, and electrophysiological measures specific to dyslexia have provided a better understanding of the reading process, particularly as it applies to individuals with dyslexia. Evidence from these studies pertaining to the neurological origins of dyslexia is reviewed, and…
Willburger, Edith; Fussenegger, Barbara; Moll, Kristina; Wood, Guilherme; Landerl, Karin
In four carefully selected samples of 8- to 10-year old children with dyslexia (but age adequate arithmetic skills), dyscalculia (but age adequate reading skills), dyslexia/dyscalculia and controls a domain-general deficit in rapid automatized naming (RAN) was found for both dyslexia groups. Dyscalculic children exhibited a domain-specific deficit…
Miles, Tim R.
Any figure given for the prevalence of dyslexia must depend on how the word "dyslexia" is defined. There is no point in defining dyslexia as "poor reading"; what is of scientific interest is the syndrome specific to developmental dyslexia, as described by Critchley (1970) and others. Difficulties arise in determining the prevalence of dyslexia in…
LDA of Minnesota, 2004
Learning Disabilities Association (LDA) of Minnesota has gotten many questions over the years about dyslexia. Examples of questions answered in this issue include: (1) When a learner reverses letters, is this dyslexia? (2) How does one teach an adult with dyslexia? (3) Can dyslexia be cured? and (4) Can GED accommodations be received for dyslexia?…
Proulx, Michael J; Elmasry, Hannah-May
Prior research on developmental dyslexia using Stroop tasks with young participants has found increased interference in participants with dyslexia relative to controls. Here we extend these findings to adult participants, and introduce a novel test of Stroop incongruity, whereby the color names appeared on an object colored in the incongruent color. The results imply that impaired inhibitory and executive attentional mechanisms are still deficient in adults with dyslexia and that other forms of attentional mechanisms, such as object-based attention, might also be impaired in dyslexia. Dyslexia arises not only from deficits in phonological processing, but from attentional mechanisms as well. PMID:24814960
Youman, Martha; Mather, Nancy
Throughout the various states of the USA, the appropriate identification of dyslexia and the timely provision of interventions are characterized by variability and inconsistency. Several states have recognized the existence of this disorder and the well-established need for services. These states have taken proactive steps to implement laws and regulations for both identification and treatment, and the provision of equal access to students who are diagnosed with dyslexia. The majority of states, however, have not developed such laws and guidelines. The purposes of this article are to review the present status and content of these dyslexia laws, highlight some differences among the laws and regulations across states, and suggest strategies for initiating such laws. PMID:23086699
Hayek, Maisam; Dorfberger, Shoshi; Karni, Avi
Children with developmental dyslexia (DD) may differ from typical readers in aspects other than reading. The notion of a general deficit in the ability to acquire and retain procedural ("how to") knowledge as long-term procedural memory has been proposed. Here, we compared the ability of elementary school children, with and without…
Jorm, Anthony F.
Jorm did not, as Ellis (TM 504 892) implies, propose that developmental and acquired phonemic-deep dyslexia are functionally equivalent. Rather, Jorm identified functional similarities. Most of Ellis' criticisms are irrelevant because they are directed at this equivalency. (Author/CP)
Quercia, Patrick; Feiss, Léonard; Michel, Carine
Developmental dyslexia affects almost 10% of school-aged children and represents a significant public health problem. Its etiology is unknown. The consistent presence of phonological difficulties combined with an inability to manipulate language sounds and the grapheme–phoneme conversion is widely acknowledged. Numerous scientific studies have also documented the presence of eye movement anomalies and deficits of perception of low contrast, low spatial frequency, and high frequency temporal visual information in dyslexics. Anomalies of visual attention with short visual attention spans have also been demonstrated in a large number of cases. Spatial orientation is also affected in dyslexics who manifest a preference for spatial attention to the right. This asymmetry may be so pronounced that it leads to a veritable neglect of space on the left side. The evaluation of treatments proposed to dyslexics whether speech or oriented towards the visual anomalies remains fragmentary. The advent of new explanatory theories, notably cerebellar, magnocellular, or proprioceptive, is an incentive for ophthalmologists to enter the world of multimodal cognition given the importance of the eye’s visual input. PMID:23690677
Ade-Ojo, Gordon O.
Learners with dyslexia are likely to be over-represented in adult literacy classes because of the convergence in perceptions, causes and understanding of literacy problems and dyslexia. Given the great amount of apprehension about practitioners' and policy makers' understanding of dyslexia itself, it is important to carry out an exploration of the…
McBride-Chang, Catherine; Lam, Fanny; Lam, Catherine; Chan, Becky; Fong, Cathy Y. C.; Wong, Terry T. Y.; Wong, Simpson W. L.
Background: This work tested the rates at which Chinese children with either language delay or familial history of dyslexia at age 5 manifested dyslexia at age 7, identified which cognitive skills at age 5 best distinguished children with and without dyslexia at age 7, and examined how these early abilities predicted subsequent literacy skills.…
Hornstra, Lisette; Denessen, Eddie; Bakker, Joep; van den Bergh, Linda; Voeten, Marinus
The present study examined teacher attitudes toward dyslexia and the effects of these attitudes on teacher expectations and the academic achievement of students with dyslexia compared to students without learning disabilities. The attitudes of 30 regular education teachers toward dyslexia were determined using both an implicit measure and an…
Mississippi State Dept. of Education, Jackson.
This handbook of procedures related to dyslexia is designed to provide guidelines for Mississippi school districts, teachers, and parents in the identification and instruction of students with dyslexia, to assist regular educators in gaining current information concerning dyslexia, accommodations and modifications, and to provide information on…
Osisanya, Ayo; Lazarus, Kelechi; Adewunmi, Abiodun
This study examined the prevalence of dyslexia and dyscalculia among persons with academic deficits in English Language and Mathematics in public primary schools in Ibadan metropolis. A correlational survey study, sampling 477 pupils who were between the ages of eight and 12 years, and in 4th and 5th grades with the use of four research…
Dyslexia is a specific learning disability, which affects reading in as many as one in five people. Many children go without proper interventions because of ineffective teaching strategies, and common myths associated with this disability. The purpose of this study was to test how deeply ingrained some myths might be, and decipher where educators…
Vlachos, Filippos; Andreou, Eleni; Delliou, Afroditi
The present study examined the link between brain hemisphericity and dyslexia in secondary school students, using the Preference Test (PT), a widely used self-report index of preferred hemisphere thinking styles. The hypothesis was that differences would be revealed between the dyslexic group and their peers in hemispheric preference. A total of…
Youman, Martha; Mather, Nancy
Throughout the various states of the USA, the appropriate identification of dyslexia and the timely provision of interventions are characterized by variability and inconsistency. Several states have recognized the existence of this disorder and the well-established need for services. These states have taken proactive steps to implement laws and…
Background: Neuroimaging offers unique opportunities for understanding the acquisition of reading by children and for unravelling the mystery of developmental dyslexia. Here, I provide a selective overview of recent neuroimaging studies, drawing out implications for education and the teaching of reading. Purpose: The different neuroimaging…
Malatesha Joshi, R.; Padakannaya, Prakash; Nishanimath, S.
This study explores the nature of reading difficulties of two bilinguals in Kannada and English, which vary in their orthographic depth and script layout. VN and MS manifest two different types of reading disabilities, dyslexia and hyperlexia, respectively. The performance of VN was below average on Kannada and English tests of phonemic awareness,…
Nigro, Luciana; Jiménez-Fernández, Gracia; Simpson, Ian C; Defior, Sylvia
One of the hallmarks of dyslexia is the failure to automatise written patterns despite repeated exposure to print. Although many explanations have been proposed to explain this problem, researchers have recently begun to explore the possibility that an underlying implicit learning deficit may play a role in dyslexia. This hypothesis has been investigated through non-linguistic tasks exploring implicit learning in a general domain. In this study, we examined the abilities of children with dyslexia to implicitly acquire positional regularities embedded in both non-linguistic and linguistic stimuli. In experiment 1, 42 children (21 with dyslexia and 21 typically developing) were exposed to rule-governed shape sequences; whereas in experiment 2, a new group of 42 children were exposed to rule-governed letter strings. Implicit learning was assessed in both experiments via a forced-choice task. Experiments 1 and 2 showed a similar pattern of results. ANOVA analyses revealed no significant differences between the dyslexic and the typically developing group, indicating that children with dyslexia are not impaired in the acquisition of simple positional regularities, regardless of the nature of the stimuli. However, within group t-tests suggested that children from the dyslexic group could not transfer the underlying positional rules to novel instances as efficiently as typically developing children. PMID:26494638
Goldstein, Bram H.; Obrzut, John E.
A study provided hemisphere specific simulation and hemispheric alluding stimuli to 15 middle school students with L-type dyslexia and 15 with P-type dyslexia. Traditional decoding and comprehension exercises were provided to 15 students with M-type dyslexia. Readers with all types of dyslexia exhibited significant improvement in reading accuracy…
Jordan, Dale R.
This book aims to interpret recent research on dyslexia into practical information for those who work with individuals with dyslexia. Chapter 1 summarizes new information about how genetic codes determine brian development and how differences in brain structure cause dyslexia. Chapter 2 explains the perceptual and emotional nature of dyslexia.…
Altieri, Jennifer L.
This article specifically looks at children's literature that portrays school-age characters with dyslexia so that the educational field can better understand how the books depict dyslexia and the school experience. Although the use of the term "dyslexia" is controversial, experts agree that dyslexia is a learning disability that affects language…
Joshi, R Malatesha; Padakannaya, Prakash; Nishanimath, S
This study explores the nature of reading difficulties of two bilinguals in Kannada and English, which vary in their orthographic depth and script layout. VN and MS manifest two different types of reading disabilities, dyslexia and hyperlexia, respectively. The performance of VN was below average on Kannada and English tests of phonemic awareness, spelling, and pseudoword naming. Despite his poor decoding skills, the listening comprehension skill both at the word level and at the sentence level of VN was within the normal range. VN, therefore, can be described to have developmental dyslexia. MS, in contrast, showed good decoding ability in both Kannada and English, but his listening and reading comprehension were poor in both languages. MS, therefore, displays a pattern of reading disability akin to that of hyperlexia. The deficits of both VN and MS, although dissimilar from each other, cut across the linguistic boundaries and affect their performance in both Kannada and English. PMID:20440742
Gan, Zhuo; Li, Chengjun; Gong, Hui; Luo, Qingming; Yao, Bin; Song, Ranran; Wu, Hanrong
Developmental dyslexia is a kind of prevalent psychologic disease. Some functional imaging technologies, such as FMRI and PET, have been used to study the brain activities of dyslexics. NIRS is a kind of novel technology which is more and more widely being used for study of the cognitive psychology. However, there aren"t reports about the dyslexic research using NIRS to be found until now. This paper introduces a NIRS system of four measuring channels. Brain activities of dyslexic subjects and normal subjects during reading task were studied with the NIRS system. Two groups of subjects, the group of dyslexia and the group of normal, were appointed to perform two reading tasks. At the same time, their cortical activities were measured with the NIRS system. This experimental result indicates that the brain activities of the dyslexic group were significantly higher than the control group in BA 48 and that NIRS can be used for the study of human brain activity.
Macnamara, Gael R.
This easy-to-use book of case studies helps you recognize the signs of dyslexia and prescribe effective teaching strategies for students with dyslexia. It includes a Case Study Analysis Sheet so you can work through important aspects of a student's personal, academic, and social life. You can then compare what you've compiled to the author's…
Reiter, Astrid; Tucha, Oliver; Lange, Klaus W.
There is little data available concerning the executive functions of children with dyslexia. The small number of existing studies in this field focus on single aspects of these functions such as working memory. The aim of the present study was therefore to assess a variety of aspects of executive functioning in children with dyslexia. Forty-two…
Wimmer, Heinz; Schurz, Matthias
This article summarizes our research on the manifestation of dyslexia in German and on cognitive deficits, which may account for the severe reading speed deficit and the poor orthographic spelling performance that characterize dyslexia in regular orthographies. An only limited causal role of phonological deficits (phonological awareness,…
Kavanagh, James F.; Yeni-Komshian, Grace
The 8-chapter booklet gives an overview of what is known and what remains to be known about developmental dyslexia. Chapter 1 defines the scope of reading problems in general, while chapter 2 defines dyslexia-"children who have difficulty learning to read, for no apparent reason". Chapter 4 outlines the normal reading process. Possible causes for…
Lockiewicz, Marta; Bogdanowicz, Katarzyna M.; Bogdanowicz, Marta
The aim of our study was to describe specific psychological resources of adults with developmental dyslexia and compare them with psychological resources of adults without developmental dyslexia. Potential differences were analyzed in visual-spatial, creative, and motivational abilities. No evidence was found for either creative, or visuospatial…
O'Brien, Beth A.; Wolf, Maryanne; Lovett, Maureen W.
Long-standing issues with the conceptualization, identification and subtyping of developmental dyslexia persist. This study takes an alternative approach to examine the heterogeneity of developmental dyslexia using taxometric classification techniques. These methods were used with a large sample of 671 children ages 6-8 who were diagnosed with…
Vance, Kate O'Brien
This article discusses how several simple adaptations in the music classroom can greatly enhance dyslexic students' learning. The sections included in this article are: (1) What Is Dyslexia?; (2) Students with Dyslexia; (3) What to Look for; (4) Adapting Instruction; (5) Reading Notation; and (6) Motor Skills. A list of practical adaptations; and…
This study examines whether two frequently reported causes of dyslexia, phonological processing problems and verbal memory impairments, represent a double-deficit or whether they are two expressions of the same deficit. Two-hundred-and-sixty-seven Dutch children aged 10-14 with dyslexia completed a list-learning task and several phonological…
The research question here was whether whole-word shape cues might facilitate reading in dyslexia following reports of how normal-reading children benefit from using this cue when learning to read. We predicted that adults with dyslexia would tend to rely more on orthographic rather than other cues when reading, and therefore would be more…
Simmons, Deborah C.
This response to Bashir and Scavuzzo (EC 602 669) suggests that their view that dyslexia is a chronic, pervasive condition is too limiting. An alternative view of dyslexia as an acute, interactive condition is proposed, and related implications for instructional curricula and reading achievement are offered. (Author/ DB)
Brunswick, Nicola, Ed.; McDougall, Sine, Ed.; de Mornay Davies, Paul, Ed.
This book provides a unique and accessible account of current research on reading and dyslexia in different orthographies. While most research has been conducted in English, this text presents cross-language comparisons to provide insights into universal aspects of reading development and developmental dyslexia in alphabetic and non-alphabetic…
Chung, Kevin K. H.; Ho, Connie Suk-Han; Chan, David W.; Tsang, Suk-Man; Lee, Suk-Han
The present study sought to identify cognitive abilities that might distinguish Hong Kong Chinese adolescents with and without dyslexia and examined the cognitive profile of dyslexic adolescents in order to better understand this important problem. The performance of 27 Chinese adolescents with childhood diagnoses of dyslexia was compared with 27…
Altmann, Lori J. P.; Lombardino, Linda J.; Puranik, Cynthia
Background: While spoken language deficits have been identified in children with developmental dyslexia, microanalysis of sentence production proficiency in these children is a largely unexplored area. Aims: The current study examines proficiency of syntactic production in children and young adults with dyslexia and typically developing…
Sawyer, Diane J.
This article introduces four papers (and responses to them) originally given at an April 1990 conference on the identification and treatment of dyslexia. Noted is the lack of consensus on what dyslexia is, how the condition comes to be, and what the nature of educational intervention ought to be, though developmental views are seen to predominate.…
Satz, Paul; Van Nostrand, Gary K.
The paper reviews a theory advanced by Satz and Sparrow (1970) which purports to explain the nature and cause of specific developmental dyslexia, and evaluates several developmental hypotheses which are generated bythe theory. The theory postulates that developmental dyslexia is not a unitary syndrome but rather reflects a lag in the maturation of…
Morken, Froydis; Helland, Turid
Research on dyslexia has largely centred on reading. The aim of this study was to assess the writing of 13 children with and 28 without dyslexia at age 11?years. A programme for keystroke logging was used to allow recording of typing activity as the children performed a sentence dictation task. Five sentences were read aloud twice each. The task…
Le Jan, Guylaine; Le Bouquin-Jeannes, Regine; Costet, Nathalie; Troles, Nolwenn; Scalart, Pascal; Pichancourt, Dominique; Faucon, Gerard; Gombert, Jean-Emile
Dyslexia is a specific disorder of language development that mainly affects reading. Etiological researches have led to multiple hypotheses which induced various diagnosis methods and rehabilitation treatments so that many different tests are used by practitioners to identify dyslexia symptoms. Our purpose is to determine a subset of the most…
Long, Louise; McPolin, Peter
The purpose of this paper is to explore parents' perceptions of the process of having their child assessed for dyslexia by an independent Educational Psychologist and the affective impact on the child or young person. The research was carried out as part of an evaluation of the services offered by the Northern Ireland Dyslexia Centre (NIDC). The…
Tops, Wim; Callens, Maaike; Lammertyn, Jan; Van Hees, Valerie; Brysbaert, Marc
An increasing number of students with dyslexia enter higher education. As a result, there is a growing need for standardized diagnosis. Previous research has suggested that a small number of tests may suffice to reliably assess students with dyslexia, but these studies were based on post hoc discriminant analysis, which tends to overestimate the…
Developmental dyslexia is believed to involve a phonological deficit of which the exact properties have not been clearly established. This article presents the findings of a longitudinal case study that suggest that, at least for some people with dyslexia, the fundamental problem involves a disturbance of temporal-spatial ordering abilities. A…
Liddle, Elizabeth B.; Jackson, Georgina M.; Rorden, Chris; Jackson, Stephen R.
Temporal and spatial attentional deficits in dyslexia were investigated using a lateralized visual temporal order judgment (TOJ) paradigm that allowed both sensitivity to temporal order and spatial attentional bias to be measured. Findings indicate that adult participants with a positive screen for dyslexia were significantly less sensitive to the…
Desroches, Amy S.; Newman, Randy Lynn; Robertson, Erin K.; Joanisse, Marc F.
Purpose: A range of studies have shown difficulties in perceiving acoustic and phonetic information in dyslexia; however, much less is known about how such difficulties relate to the perception of individual words. The authors present data from event-related potentials (ERPs) examining the hypothesis that children with dyslexia have difficulties…
Bogaerts, Louisa; Szmalec, Arnaud; Hachmann, Wibke M; Page, Mike P A; Duyck, Wouter
The present study investigated long-term serial-order learning impairments, operationalized as reduced Hebb repetition learning (HRL), in people with dyslexia. In a first multi-session experiment, we investigated both the persistence of a serial-order learning impairment as well as the long-term retention of serial-order representations, both in a group of Dutch-speaking adults with developmental dyslexia and in a matched control group. In a second experiment, we relied on the assumption that HRL mimics naturalistic word-form acquisition and we investigated the lexicalization of novel word-forms acquired through HRL. First, our results demonstrate that adults with dyslexia are fundamentally impaired in the long-term acquisition of serial-order information. Second, dyslexic and control participants show comparable retention of the long-term serial-order representations in memory over a period of 1 month. Third, the data suggest weaker lexicalization of newly acquired word-forms in the dyslexic group. We discuss the integration of these findings into current theoretical views of dyslexia. PMID:26164302
Kannangara, Chathurika S.
This is an account of personal narratives shared by several people with dyslexia. Most of these are presented in their original quotation format to provide personal accounts of the lives of people with dyslexia. In this paper the author shares her conversations with her participants. This paper provides an original conceptual model, which is currently been tested empirically. Dyslexia affects the learning process in areas as such reading, and spelling. Conversely abilities or strengths can be seen in other areas, such as developing coping strategies to manage and overcome challenges. This research aims to adapt positive psychology techniques to support individuals with dyslexia. To develop positive psychology interventions, individuals will be helped to discover their five signature strengths. The VIA (Values in Action) Strengths Survey has been hosted in a website which has been developed in the form of a dyslexia user friendly format, such as providing the ability for respondents to change fonts and font sizes, colors and a text to speech option. This paper introduces the theoretical model of ‘How to move from Languishing Dyslexia to Thriving Dyslexia.’ PMID:26733933
Kannangara, Chathurika S
This is an account of personal narratives shared by several people with dyslexia. Most of these are presented in their original quotation format to provide personal accounts of the lives of people with dyslexia. In this paper the author shares her conversations with her participants. This paper provides an original conceptual model, which is currently been tested empirically. Dyslexia affects the learning process in areas as such reading, and spelling. Conversely abilities or strengths can be seen in other areas, such as developing coping strategies to manage and overcome challenges. This research aims to adapt positive psychology techniques to support individuals with dyslexia. To develop positive psychology interventions, individuals will be helped to discover their five signature strengths. The VIA (Values in Action) Strengths Survey has been hosted in a website which has been developed in the form of a dyslexia user friendly format, such as providing the ability for respondents to change fonts and font sizes, colors and a text to speech option. This paper introduces the theoretical model of 'How to move from Languishing Dyslexia to Thriving Dyslexia.' PMID:26733933
Helland, Turid; Kaasa, Randi
This study focused on English as L2 in a group of Norwegian dyslexic 12 year olds, compared to an age and gender matched control group. Norwegian school children learn English from the first grades on. The subjects were assessed with a test battery of verbal and written tasks. First, they were given a comprehension task; second, a model sentence task; third, two pragmatic tasks, and fourth, three tasks of literacy. The verbal tasks were scored according to comprehension, morphology, syntax and semantics, while the literacy tasks were scored by spelling, translation and reading skills. It was hypothesized that the results of the control group and the dyslexia group would differ on all tasks, but that subgrouping the dyslexia group by comprehension skills would show heterogeneity within the dyslexia group. The data analyses confirmed these hypotheses. Significant differences were seen between the dyslexia group and the control group. However, the subgrouping revealed minor differences between the control group and the subgroup with good comprehension skills, and major differences between the control group and the subgroup with poor comprehension skills. Especially morphology and spelling were difficult for the dyslexia group. The results were tentatively discussed within the framework of biological and cognitive models of how to interpret L2 performance in dyslexia, underlining the importance of further research in L2 acquisition in dyslexia. PMID:15747806
Handler, Sheryl M; Fierson, Walter M; Section on Ophthalmology
Learning disabilities constitute a diverse group of disorders in which children who generally possess at least average intelligence have problems processing information or generating output. Their etiologies are multifactorial and reflect genetic influences and dysfunction of brain systems. Reading disability, or dyslexia, is the most common learning disability. It is a receptive language-based learning disability that is characterized by difficulties with decoding, fluent word recognition, rapid automatic naming, and/or reading-comprehension skills. These difficulties typically result from a deficit in the phonologic component of language that makes it difficult to use the alphabetic code to decode the written word. Early recognition and referral to qualified professionals for evidence-based evaluations and treatments are necessary to achieve the best possible outcome. Because dyslexia is a language-based disorder, treatment should be directed at this etiology. Remedial programs should include specific instruction in decoding, fluency training, vocabulary, and comprehension. Most programs include daily intensive individualized instruction that explicitly teaches phonemic awareness and the application of phonics. Vision problems can interfere with the process of reading, but children with dyslexia or related learning disabilities have the same visual function and ocular health as children without such conditions. Currently, there is inadequate scientific evidence to support the view that subtle eye or visual problems cause or increase the severity of learning disabilities. Because they are difficult for the public to understand and for educators to treat, learning disabilities have spawned a wide variety of scientifically unsupported vision-based diagnostic and treatment procedures. Scientific evidence does not support the claims that visual training, muscle exercises, ocular pursuit-and-tracking exercises, behavioral/perceptual vision therapy, "training" glasses
Soltész, Fruzsina; Szűcs, Denes; Leong, Victoria; White, Sonia; Goswami, Usha
Oscillatory entrainment to the speech signal is important for language processing, but has not yet been studied in developmental disorders of language. Developmental dyslexia, a difficulty in acquiring efficient reading skills linked to difficulties with phonology (the sound structure of language), has been associated with behavioural entrainment deficits. It has been proposed that the phonological ‘deficit’ that characterises dyslexia across languages is related to impaired auditory entrainment to speech at lower frequencies via neuroelectric oscillations (<10 Hz, ‘temporal sampling theory’). Impaired entrainment to temporal modulations at lower frequencies would affect the recovery of the prosodic and syllabic structure of speech. Here we investigated event-related oscillatory EEG activity and contingent negative variation (CNV) to auditory rhythmic tone streams delivered at frequencies within the delta band (2 Hz, 1.5 Hz), relevant to sampling stressed syllables in speech. Given prior behavioural entrainment findings at these rates, we predicted functionally atypical entrainment of delta oscillations in dyslexia. Participants performed a rhythmic expectancy task, detecting occasional white noise targets interspersed with tones occurring regularly at rates of 2 Hz or 1.5 Hz. Both groups showed significant entrainment of delta oscillations to the rhythmic stimulus stream, however the strength of inter-trial delta phase coherence (ITC, ‘phase locking’) and the CNV were both significantly weaker in dyslexics, suggestive of weaker entrainment and less preparatory brain activity. Both ITC strength and CNV amplitude were significantly related to individual differences in language processing and reading. Additionally, the instantaneous phase of prestimulus delta oscillation predicted behavioural responding (response time) for control participants only. PMID:24204644
Snowling, Margaret J; Melby-Lervåg, Monica
This article reviews 95 publications (based on 21 independent samples) that have examined children at family risk of reading disorders. We report that children at family risk of dyslexia experience delayed language development as infants and toddlers. In the preschool period, they have significant difficulties in phonological processes as well as with broader language skills and in acquiring the foundations of decoding skill (letter knowledge, phonological awareness and rapid automatized naming [RAN]). Findings are mixed with regard to auditory and visual perception: they do not appear subject to slow motor development, but lack of control for comorbidities confounds interpretation. Longitudinal studies of outcomes show that children at family risk who go on to fulfil criteria for dyslexia have more severe impairments in preschool language than those who are defined as normal readers, but the latter group do less well than controls. Similarly at school age, family risk of dyslexia is associated with significantly poor phonological awareness and literacy skills. Although there is no strong evidence that children at family risk are brought up in an environment that differs significantly from that of controls, their parents tend to have lower educational levels and read less frequently to themselves. Together, the findings suggest that a phonological processing deficit can be conceptualized as an endophenotype of dyslexia that increases the continuous risk of reading difficulties; in turn its impact may be moderated by protective factors. (PsycINFO Database Record PMID:26727308
This article reviews 95 publications (based on 21 independent samples) that have examined children at family risk of reading disorders. We report that children at family risk of dyslexia experience delayed language development as infants and toddlers. In the preschool period, they have significant difficulties in phonological processes as well as with broader language skills and in acquiring the foundations of decoding skill (letter knowledge, phonological awareness and rapid automatized naming [RAN]). Findings are mixed with regard to auditory and visual perception: they do not appear subject to slow motor development, but lack of control for comorbidities confounds interpretation. Longitudinal studies of outcomes show that children at family risk who go on to fulfil criteria for dyslexia have more severe impairments in preschool language than those who are defined as normal readers, but the latter group do less well than controls. Similarly at school age, family risk of dyslexia is associated with significantly poor phonological awareness and literacy skills. Although there is no strong evidence that children at family risk are brought up in an environment that differs significantly from that of controls, their parents tend to have lower educational levels and read less frequently to themselves. Together, the findings suggest that a phonological processing deficit can be conceptualized as an endophenotype of dyslexia that increases the continuous risk of reading difficulties; in turn its impact may be moderated by protective factors. PMID:26727308
Ripamonti, E; Aggujaro, S; Molteni, F; Zonca, G; Frustaci, M; Luzzatti, C
In this study we investigated the neural correlates of acquired reading disorders through an anatomo-correlative procedure of the lesions of 59 focal brain damaged patients suffering from acquired surface, phonological, deep, undifferentiated dyslexia and pure alexia. Two reading tasks, one of words and nonwords and one of words with unpredictable stress position, were used for this study. We found that surface dyslexia was predominantly associated with left temporal lesions, while in phonological dyslexia the lesions overlapped in the left insula and the left inferior frontal gyrus (pars opercularis) and that pure alexia was associated with lesions in the left fusiform gyrus. A number of areas and white matter tracts, which seemed to involve processing along both the lexical and the sublexical routes, were identified for undifferentiated dyslexia. Two cases of deep dyslexia with relatively dissimilar anatomical correlates were studied, one compatible with Coltheart's right-hemisphere hypothesis (1980) whereas the other could be interpreted in the context of Morton and Patterson's (1980), multiply-damaged left-hemisphere hypothesis. In brief, the results of this study are only partially consistent with the current state of the art, and propose new and stimulating challenges; indeed, based on these results we suggest that different types of acquired dyslexia may ensue after different cortical damage, but white matter disconnection may play a crucial role in some cases. PMID:24815949
Pavlidis, George Th.
Describes experiments showing that the eye movement patterns of dyslexic children differed from those of normal and backward readers during both a reading and a nonreading task. Discusses possible causes of dyslexia and ways of diagnosing it. (GT)
Łockiewicz, Marta; Bogdanowicz, Katarzyna M; Bogdanowicz, Marta
The aim of our study was to describe specific psychological resources of adults with developmental dyslexia and compare them with psychological resources of adults without developmental dyslexia. Potential differences were analyzed in visual-spatial, creative, and motivational abilities. No evidence was found for either creative, or visuospatial superiority in adults with developmental dyslexia. The results suggest, however, that visual-spatial processing of nonverbal material by adults with developmental dyslexia allows them to efficiently execute tasks that are based on sequential material. Moreover, the participants with specific difficulties in reading and writing exhibited a significantly higher level of aspirations than their peers without such difficulties with a comparable level of educational achievement. These results suggest that succeeding in different fields by highly functioning adult dyslexics may depend on personality and motivational factors, rather than cognitive factors. PMID:23462191
Punt, Marja; de Jong, Marianne; de Groot, Erik; Hadders-Algra, Mijna
Aim: To improve understanding of brain function in children with severe dyslexia in terms of minor neurological dysfunctions (MNDs). Method: One hundred and four children (81 males, 23 females; age range 7-12y; mean age 9y 7mo, SD 1y 2mo;) with severe dyslexia (the presence of a Full-scale IQ score of greater than or equal to 85, retardation in…
Crisp, Jenni; Lambon Ralph, Matthew A
It has been argued that normal reading and acquired dyslexias reflect the role of three underlying primary systems (phonology, semantics, and vision) rather than neural mechanisms dedicated to reading. This proposal is potentially consistent with the suggestion that phonological and deep dyslexia represent variants of a single reading disorder rather than two separate entities. The current study explored this possibility, the nature of any continuum between the disorders, and the possible underlying bases of it. A case series of patients were given an assessment battery to test for the characteristics of phonological and deep dyslexia. The status of their underlying phonological and semantic systems was also investigated. The majority of participants exhibited many of the symptoms associated with deep dyslexia whether or not they made semantic errors. Despite wide variation in word and nonword reading accuracy, there was considerable symptom overlap across the cohort and, thus, no sensible dividing line to separate the participants into distinct groups. The patient data indicated that the deep-phonological continuum might best be characterized according to the severity of the individual's reading impairment rather than in terms of a strict symptom succession. Assessments of phonological and semantic impairments suggested that the integrity of these primary systems underpinned the patients' reading performance. This proposal was supported by eliciting the symptoms of deep-phonological dyslexia in nonreading tasks. PMID:16513001
Hiscox, Lucy; Leonavičiūtė, Erika; Humby, Trevor
Dyslexia is associated with difficulties in language-specific skills such as spelling, writing and reading; the difficulty in acquiring literacy skills is not a result of low intelligence or the absence of learning opportunity, but these issues will persist throughout life and could affect long-term education. Writing is a complex process involving many different functions, integrated by the working memory system; people with dyslexia have a working memory deficit, which means that concentration on writing quality may be detrimental to understanding. We confirm impaired working memory in a sample of university students with (compensated) dyslexia, and using a within-subject design with three test conditions, we show that these participants demonstrated better understanding of a piece of text if they had used automatic spelling correction software during a dictation/transcription task. We hypothesize that the use of the autocorrecting software reduced demand on working memory, by allowing word writing to be more automatic, thus enabling better processing and understanding of the content of the transcriptions and improved recall. Long-term and regular use of autocorrecting assistive software should be beneficial for people with and without dyslexia and may improve confidence, written work, academic achievement and self-esteem, which are all affected in dyslexia. PMID:24976387
Di Filippo, Gloria; Zoccolotti, Pierluigi; Ziegler, Johannes C.
According to a recent theory of dyslexia, the "perceptual anchor theory," children with dyslexia show deficits in classic auditory and phonological tasks not because they have auditory or phonological impairments but because they are unable to form a "perceptual anchor" in tasks that rely on a small set of repeated stimuli. The theory makes the…
Kender, Joseph P.; Kender, Mark A.
Reviews some of the most pertinent current research on possible causes of dyslexia. Offers guidelines for the prognosis and treatment of dyslexics and literary options for reading teachers and specialists to use in working with dyslexia. (PA)
Olofsson, Åke; Taube, Karin; Ahl, Astrid
Broadened recruitment to higher education is on the agenda in many countries, and it is also widely recognized that the number of dyslexic students entering higher education is increasing. In Sweden, as in many other European countries, higher education institutions are required to accommodate students with dyslexia. The present study focuses on the study outcome for 50 students with diagnosed dyslexia, mainly in teacher education and nurses' training, at three universities in Northern Sweden. The students trusted their own ability to find information on the Internet but mistrusted their own abilities in reading course books and articles in English and in taking notes. The mean rate of study was 23.5 European Credit Transfer and Accumulation System credits per semester, which is slightly below the national baseline of 26.7. The results show that more than half of the students are examined at a normal rate of study but that about one fifth have a very low rate of study. Messages Most students with dyslexia can compensate for their reading problems. Taking notes during lessons and reading in foreign language may be especially difficult for students with dyslexia. Diagnoses should distinguish between reading comprehension and word decoding. More than half of the students with dyslexia can achieve at a normal rate of study. One-fifth of the students with dyslexia may need a longer period of study than other students. PMID:26459832
Vicari, S; Finzi, A; Menghini, D; Marotta, L; Baldi, S; Petrosini, L
Objective: The purpose of this study was to investigate the effects of specific types of tasks on the efficiency of implicit procedural learning in the presence of developmental dyslexia (DD). Methods: Sixteen children with DD (mean (SD) age 11.6 (1.4) years) and 16 matched normal reader controls (mean age 11.4 (1.9) years) were administered two tests (the Serial Reaction Time test and the Mirror Drawing test) in which implicit knowledge was gradually acquired across multiple trials. Although both tests analyse implicit learning abilities, they tap different competencies. The Serial Reaction Time test requires the development of sequential learning and little (if any) procedural learning, whereas the Mirror Drawing test involves fast and repetitive processing of visuospatial stimuli but no acquisition of sequences. Results: The children with DD were impaired on both implicit learning tasks, suggesting that the learning deficit observed in dyslexia does not depend on the material to be learned (with or without motor sequence of response action) but on the implicit nature of the learning that characterises the tasks. Conclusion: Individuals with DD have impaired implicit procedural learning. PMID:16170083
Cestari, Tania Ferreira; Dantas, Lia Pinheiro; Boza, Juliana Catucci
Cutaneous hyperpigmentations are frequent complaints, motivating around 8.5% of all dermatological consultations in our country. They can be congenital, with different patterns of inheritance, or acquired in consequence of skin problems, systemic diseases or secondary to environmental factors. The vast majority of them are linked to alterations on the pigment melanin, induced by different mechanisms. This review will focus on the major acquired hyperpigmentations associated with increased melanin, reviewing their mechanisms of action and possible preventive measures. Particularly prominent aspects of diagnosis and therapy will be emphasized, with focus on melasma, post-inflammatory hyperpigmentation, periorbital pigmentation, dermatosis papulosa nigra, phytophotodermatoses, flagellate dermatosis, erythema dyschromicum perstans, cervical poikiloderma (Poikiloderma of Civatte), acanthosis nigricans, cutaneous amyloidosis and reticulated confluent dermatitis PMID:24626644
Bacon, Alison M.; Bennett, Samantha
Increasing numbers of students in Higher Education (HE) have dyslexia and are particularly over represented in the visual and creative arts. While dyslexia has been associated with artistic talent, some applicants may perceive their academic opportunities as limited because of negative learning experiences associated with their dyslexia. This…
General cognitive ability is still a factor in current definitions of dyslexia despite two decades of research showing little or no relevance to the nature of dyslexia. This article suggests one reason why this may be so. The suggestion is based on a distinction between dyslexia as a disability (poor ability)--as it is viewed and explained by…
Liu, Wenli; Shu, Hua; Yang, Yufang
Findings concerning the relation between dyslexia and speech perception deficits are inconsistent in the literature. This study examined the relation in Chinese children using a more homogeneous sample--children with phonological dyslexia. Two experimental tasks were administered to a group of Chinese children with phonological dyslexia, a group…
Hudson, Roxanne F.; High, Leslie; Al Otaiba, Stephanie
Dyslexia is a disorder of the language-processing systems in the brain. It is a specific learning disability in reading that often affects spelling as well. This article describes: (1) Common characteristics experienced by people with dyslexia or reading disabilities; (2) Common misconceptions about dyslexia; (3) What brain research tell us about…
Lindgren, Signe-Anita; Laine, Matti
High-performing adults with compensated dyslexia pose particular challenges to dyslexia diagnostics. We compared the performance of 20 multilingual Finnish university students with suspected dyslexia with 20 age-matched and education-matched controls on an extensive test battery. The battery tapped various aspects of reading, writing, word…
LDA Minnesota, 2010
This issue of "Learning Times" includes a feature on understanding dyslexia. Dyslexia is a brain-based, often inherited, disorder that impairs a person's ability to read. It is not the result of low intelligence, lack of motivation, sensory impairment, or inadequate instruction. Early diagnosis of dyslexia is critical, and a child can be reliably…
Two studies investigated whether an appropriate versus an inappropriate hemisphere alluding stimulation treatment of children with L-type dyslexia produces differential reading effects, and effects of hemisphere specific stimulation on children with L-, P-, and M-type dyslexia. Results support the validity of dyslexia subtyping and the…
Leong, Che Kan
This commentary reviews forthcoming articles on the scientific study of dyslexia, genetic and neurophysiological aspects of dyslexia, cross-linguistic aspects of literacy development and dyslexia, and theory-based practice. It concludes that educators should continue to strive to promote theory-based research and evidence-based practice to achieve…
Wiseheart, Rebecca; Altmann, Lori J. P.; Park, Heeyoung; Lombardino, Linda J.
This study investigated the effects of syntactic complexity on written sentence comprehension in compensated adults with dyslexia. Because working memory (WM) plays a key role in processing complex sentences, and individuals with dyslexia often demonstrate persistent deficits in WM, we hypothesized that individuals with dyslexia would perform more…
Nelson, Jason M.; Gregg, Noel
Objective: To investigate depressive and anxious symptomatology among transitioning adolescents and college students with ADHD, dyslexia, or comorbid ADHD/dyslexia. Method: Transitioning adolescents and college students with these disorders along with a non-ADHD/dyslexia college sample completed self-report measures of depression and anxiety.…
Jaśkowski, Piotr; Rusiak, Patrycja
Hari et al. (Brain 174:1373-1380, 2001) demonstrated that dyslexics showed a sluggish attention capture in both visual hemifields. Additionally, they indicated a left-right asymmetry in the perception of temporal order of two visual stimuli (they performed worse than controls only if the stimulus in the left hemifield preceded that in right hemifield). They suggested that a left-sided minineglect is associated with dyslexia. We hypothesized that if a kind of neglect syndrome is responsible for the asymmetry they found, dyslexics should not only show a left-right asymmetry in temporal order judgment of two laterally presented stimuli but also perform equally well as controls when the stimuli are vertically aligned. Our results indicated that in both tasks dyslexics performed generally worse than normal readers. The results suggest that dyslexics suffer from a more general problem of order discrimination. PMID:17028891
Houpt, Joseph W.; Sussman, Bethany L.; Townsend, James T.; Newman, Sharlene D.
Developmental dyslexia is a complex and heterogeneous disorder characterized by unexpected difficulty in learning to read. Although it is considered to be biologically based, the degree of variation has made the nature and locus of dyslexia difficult to ascertain. Hypotheses regarding the cause have ranged from low-level perceptual deficits to higher order cognitive deficits, such as phonological processing and visual-spatial attention. We applied the capacity coefficient, a measure obtained from a mathematical cognitive model of response times to measure how efficiently participants processed different classes of stimuli. The capacity coefficient was used to test the extent to which individuals with dyslexia can be distinguished from normal reading individuals based on their ability to take advantage of word, pronounceable non-word, consonant sequence or unfamiliar context when categorizing character strings. Within subject variability of the capacity coefficient across character string types was fairly regular across normal reading adults and consistent with a previous study of word perception with the capacity coefficient—words and pseudowords were processed at super-capacity and unfamiliar characters strings at limited-capacity. Two distinct patterns were observed in individuals with dyslexia. One group had a profile similar to the normal reading adults while the other group showed very little variation in capacity across string-type. It is possible that these individuals used a similar strategy for all four string-types and were able to generalize this strategy when processing unfamiliar characters. This difference across dyslexia groups may be used to identify sub-types of the disorder and suggest significant differences in word level processing among these subtypes. Therefore, this approach may be useful in further delineating among types of dyslexia, which in turn may lead to better understanding of the etiologies of dyslexia. PMID:25954234
Houpt, Joseph W; Sussman, Bethany L; Townsend, James T; Newman, Sharlene D
Developmental dyslexia is a complex and heterogeneous disorder characterized by unexpected difficulty in learning to read. Although it is considered to be biologically based, the degree of variation has made the nature and locus of dyslexia difficult to ascertain. Hypotheses regarding the cause have ranged from low-level perceptual deficits to higher order cognitive deficits, such as phonological processing and visual-spatial attention. We applied the capacity coefficient, a measure obtained from a mathematical cognitive model of response times to measure how efficiently participants processed different classes of stimuli. The capacity coefficient was used to test the extent to which individuals with dyslexia can be distinguished from normal reading individuals based on their ability to take advantage of word, pronounceable non-word, consonant sequence or unfamiliar context when categorizing character strings. Within subject variability of the capacity coefficient across character string types was fairly regular across normal reading adults and consistent with a previous study of word perception with the capacity coefficient-words and pseudowords were processed at super-capacity and unfamiliar characters strings at limited-capacity. Two distinct patterns were observed in individuals with dyslexia. One group had a profile similar to the normal reading adults while the other group showed very little variation in capacity across string-type. It is possible that these individuals used a similar strategy for all four string-types and were able to generalize this strategy when processing unfamiliar characters. This difference across dyslexia groups may be used to identify sub-types of the disorder and suggest significant differences in word level processing among these subtypes. Therefore, this approach may be useful in further delineating among types of dyslexia, which in turn may lead to better understanding of the etiologies of dyslexia. PMID:25954234
Wu, Xiao-qin; Liu, Xiao-Jia; Sun, Zhao-chun; Chromik, Lindsay; Zhang, Ya-wei
We describe a 44-year-old Chinese-speaking patient with semantic dementia (SD), who demonstrates dyslexia and dysgraphia. The man was administered a series of neuropsychological inspections, including general language tests and reading and writing examinations. The patient demonstrated surface dyslexia when reading single Chinese characters aloud. While most writing errors demonstrated by the patient were orthographically similar errors and noncharacter responses, such as pictograph, logographeme, and stroke errors, rather than phonologically plausible errors that were homophonous or different only in tone from the targets. We suggest that the type of acquired dysgraphia demonstrated by Chinese-speaking SD patients is determined by the unique features of the Chinese writing system. PMID:24606031
Bakker, D J
Evidence shows that initial and advanced learning to read are predominantly mediated by the right and left cerebral hemispheres, respectively. Premature reliance on left-hemispheric reading strategies may result in L-type dyslexia, characterized by hurried and inaccurate reading. P-type dyslexia, characterized by a slow and fragmented style of reading, may result from the inability to shift from the predominant generation of right-hemispheric reading strategies to the predominant generation of left-hemispheric reading strategies. Results of investigations concerning the validity of the L/P-typology are discussed, as are the reading effects of hemisphere-specific and hemisphere-alluding stimulation in children with L- and P-type dyslexia. PMID:1583415
Männel, Claudia; Meyer, Lars; Wilcke, Arndt; Boltze, Johannes; Kirsten, Holger; Friederici, Angela D
Developmental dyslexia, a severe impairment of literacy acquisition, is known to have a neurological basis and a strong genetic background. However, effects of individual genetic variations on dyslexia-associated deficits are only moderate and call for the assessment of the genotype's impact on mediating neuro-endophenotypes by the imaging genetics approach. Using voxel-based morphometry (VBM) in German participants with and without dyslexia, we investigated gray matter changes and their association with impaired phonological processing, such as reduced verbal working memory. These endophenotypical alterations were, together with dyslexia-associated genetic variations, examined on their suitability as potential predictors of dyslexia. We identified two gray matter clusters in the left posterior temporal cortex related to verbal working memory capacity. Regional cluster differences correlated with genetic risk variants in TNFRSF1B. High-genetic-risk participants exhibit a structural predominance of auditory-association areas relative to auditory-sensory areas, which may partly compensate for deficient early auditory-sensory processing stages of verbal working memory. The reverse regional predominance observed in low-genetic-risk participants may in turn reflect reliance on these early auditory-sensory processing stages. Logistic regression analysis further supported that regional gray matter differences and genetic risk interact in the prediction of individuals' diagnostic status: With increasing genetic risk, the working-memory related structural predominance of auditory-association areas relative to auditory-sensory areas classifies participants with dyslexia versus control participants. Focusing on phonological deficits in dyslexia, our findings suggest endophenotypical changes in the left posterior temporal cortex could comprise novel pathomechanisms for verbal working memory-related processes translating TNFRSF1B genotype into the dyslexia phenotype. PMID
Varvara, Pamela; Varuzza, Cristiana; Sorrentino, Anna C. P.; Vicari, Stefano; Menghini, Deny
The present study was aimed at investigating different aspects of Executive Functions (EF) in children with Developmental Dyslexia (DD). A neuropsychological battery tapping verbal fluency, spoonerism, attention, verbal shifting, short-term and working memory was used to assess 60 children with DD and 65 with typical reading (TR) abilities. Compared to their controls, children with DD showed deficits in several EF domains such as verbal categorical and phonological fluency, visual-spatial and auditory attention, spoonerism, verbal and visual short-term memory, and verbal working memory. Moreover, exploring predictive relationships between EF measures and reading, we found that spoonerism abilities better explained word and non-word reading deficits. Although to a lesser extent, auditory and visual-spatial attention also explained the increased percentage of variance related to reading deficit. EF deficits found in DD are interpreted as an expression of a deficient functioning of the Central Executive System and are discussed in the context of the recent temporal sampling theory. PMID:24639640
Fitzpatrick, Velvet R.
In the United States, institutions have established multiple programs and initiatives aimed at increasing the diversity of both faculty and students in engineering as means to produce a workforce that will better serve society. However, there are two major problems in addressing engineering student diversity. First, the engineering education research community has paid little attention to date as to how engineering education research characterizes diversity in its broadest sense. Second, research on persons with disabilities in undergraduates engineering, a population of interests within diversity, is minimal. Available disability studies tend to be skewed toward physical disabilities, leading to a neglect of cognitive differences such as learning disabilities (LD). In addition, disability research questions and study designs are inherently steeped in ability bias. The purpose of this dissertation is to explore the meaning of ability for students with dyslexia while in undergraduate engineering and establish the significance of cognitive diversity, focusing on LD and more specifically dyslexia, in undergraduate engineering education and answer the following research question: How do undergraduate engineering students with dyslexia experience ability while pursuing and persisting in engineering? The motivation was to lay the groundwork for future engineering education studies on undergraduate students with LD in general but dyslexia in specific. The first goal was to conduct a critical literature review pertaining to the academic strengths of undergraduate students with LD, specifically, dyslexia and the second goal was to describe how undergraduate engineering students with dyslexia experience ability. The intent was not to redefine dyslexia or disability. The intent is to provide an inclusive account of dyslexia, weakness and strengths, within the field of engineering education. This study was conducted from a qualitative inquiry approach, within the social
Kezilas, Yvette; Kohnen, Saskia; McKague, Meredith; Castles, Anne
Many children with reading difficulties display phonological deficits and struggle to acquire non-lexical reading skills. However, not all children with reading difficulties have these problems, such as children with selective letter position dyslexia (LPD), who make excessive migration errors (such as reading slime as “smile”). Previous research has explored three possible loci for the deficit – the phonological output buffer, the orthographic input lexicon, and the orthographic-visual analysis stage of reading. While there is compelling evidence against a phonological output buffer and orthographic input lexicon deficit account of English LPD, the evidence in support of an orthographic-visual analysis deficit is currently limited. In this multiple single-case study with three English-speaking children with developmental LPD, we aimed to both replicate and extend previous findings regarding the locus of impairment in English LPD. First, we ruled out a phonological output buffer and an orthographic input lexicon deficit by administering tasks that directly assess phonological processing and lexical guessing. We then went on to directly assess whether or not children with LPD have an orthographic-visual analysis deficit by modifying two tasks that have previously been used to localize processing at this level: a same-different decision task and a non-word reading task. The results from these tasks indicate that LPD is most likely caused by a deficit specific to the coding of letter positions at the orthographic-visual analysis stage of reading. These findings provide further evidence for the heterogeneity of dyslexia and its underlying causes. PMID:24917802
Taylor, Mark J.; Duffy, Sandi; England, David
Purpose: The purpose of this paper is to examine the type of adjustments to delivery appropriate for students with dyslexia in a UK higher education setting. Design/methodology/approach: A case study in a UK university department was conducted over a four-year period. Findings: It was found that a variety of adjustments may be required for…
Evans, Henryka M.; Seymour, Philip H. K.
An assessment of foundation processes was administered to 51 Scottish children with reading difficulties and to 56 reading-level-matched controls. Results suggested the foundation is in place by the reading age of 7 years and that foundation-level dyslexia is identifiable in children with reading difficulty whose reading ages fall below this…
Helland, Turid; Asbjornsen, Arve E.; Hushovd, Aud Ellen; Hugdahl, Kenneth
This study focused on the relationship between school performance and performance on a dichotic listening (DL) task in dyslexic children. Dyslexia is associated with impaired phonological processing, related to functions in the left temporal lobe. DL is a frequently used task to assess functions of the left temporal lobe. Due to the predominance…
Duranovic, Mirela; Tinjak, Sanela; Turbic-Hadzagic, Amira
The phonological skills are not the only linguistic abilities which are observed to have some influence on reading achievement in dyslexics. In addition to phonological skills, morphological skills should be also taken in consideration. The aim of this study is to extend investigation the linguistic abilities of children with dyslexia to the…
Salmelin, Riitta; Helenius, Paivi
In reading tasks, an underactivation of the left inferior occipitotemporal cortex in dyslexia seems to be the most consistent finding both in neurophysiological and hemodynamic studies. This marked difference appears at about 150 msec after word presentation when the brain enters the letter-string-specific (or, more generally, object-specific)…
Galaburda, Albert M.
The author considers cerebral dominance and brain asymmetry, the development of the cerebral cortex and examples of aberrancy, and diseases of the immune system, all of which relate to recent anatomical and epidemiological findings in developmental dyslexia. These discoveries have led to testable hypotheses which may enhance current understandings…
Howard Gardner's multiple intelligences theory has exciting implications for planning new curricula, especially for children with dyslexia. These children have been "educated" in a system that has failed them. Gardner's theory allows an open-ended approach to assessing dyslexic children's intelligence. Understanding the eight intelligences can…
Haddad, Herskel M.; And Others
In 73 children (6-13 years old) with reading difficulty, ophthalmological evaluation showed that 18 had overt refractive errors, 18 dyslexia and no ocular anomalies, and 37 impaired fusional amplitudes, 24 of whom were dyslexic. In all Ss with poor fusional amplitudes the reading mechanism could be improved with orthoptic exercises. (Author/CL)
Buchholz, Judy; Davies, Anne Aimola
Alerting, orienting and executive control of attention are investigated in five adult cases of dyslexia. In comparison with a control group, alerting and executive control were found to be generally intact for each case. Two spatial cueing tasks were employed. For the task requiring target detection, orienting difficulties were evident only in…
A recent British government report on low literacy largely ignored dyslexia. Any approach to remediating basic skills must recognize the needs of dyslexic adults as well as their strengths: intuitive understanding of how things work, problem solving and troubleshooting abilities, and heightened visualization and creativity. (SK)
Moncrieff, Deborah W.; Black, Jeffrey R.
Several auditory processing deficits have been reported in children with dyslexia. In order to assess for the presence of a binaural integration type of auditory processing deficit, dichotic listening tests with digits, words and consonant-vowel (CV) pairs were administered to two groups of right-handed 11-year-old children, one group diagnosed…
Morken, Frøydis; Helland, Turid
Research on dyslexia has largely centred on reading. The aim of this study was to assess the writing of 13 children with and 28 without dyslexia at age 11 years. A programme for keystroke logging was used to allow recording of typing activity as the children performed a sentence dictation task. Five sentences were read aloud twice each. The task was to type the sentence as correctly as possible, with no time constraints. The data were analysed from a product (spelling, grammar and semantics) and process (transcription fluency and revisions) perspective, using repeated measures ANOVA and t-tests to investigate group differences. Furthermore, the data were correlated with measures of rapid automatic naming and working memory. Results showed that the group with dyslexia revised their texts as much as the typical group, but they used more time, and the result was poorer. Moreover, rapid automatic naming correlated with transcription fluency, and working memory correlated with the number of semantic errors. This shows that dyslexia is generally not an issue of effort and that cognitive skills that are known to be important for reading also affect writing. PMID:23720272
Aaron, P. G.; And Others
Reading-disabled children (n=36) in grades four through eight were matched for reading comprehension and placed into two groups based on listening comprehension. Poor readers with normal listening comprehension had average or above intelligence quotients, conforming to the traditional definition of dyslexia and contrasting with poor readers with…
Galaburda, Albert M.
In response to M. Rawson's paper, the author uses an analogy with coronary artery disease to show that current brain research is not entirely at odds with the position that dyslexia may be a developmental variation, rather than a defect. (Author/DB)
Festinger, Leon; And Others
Eye movements of 18 male and seven female dyslexic children and 10 normal children were evaluated to determine if eye movement disorders may be the cause of some of the symptoms associated with dyslexia. Data on eye movements were collected while Ss moved their eyes from one fixation point to another in a nonreading situation. Errors in vertical…
In a continuation study, 12 students with dyslexia participated in muscle testing and exercises. Six areas were evaluated via pre- and post-tests: academics (using measures of spelling, reading, and math); parental observations of changes in their children (behavioral, academic or affective); perceptual drawing; oral reading; written language; and…
Singleton, Chris; Horne, Joanna; Simmons, Fiona
Identifying dyslexia in adulthood presents particular challenges because of complicating factors such as acquisition of compensatory strategies, differing degrees of intervention and the problem of distinguishing dyslexic adults from those whose literacy difficulties have non-cognitive causes. One of the implications is that conventional literacy…
Smith, Shelley D.; And Others
Examines the "sib pair" method of linkage analysis designed to locate genes influencing dyslexia, which has several advantages over the "LOD" score method. Notes that the sib pair analysis was able to detect the same linkages as the LOD method, plus a possible third region. Confirms that the sib pair method is an effective means of screening. (RS)
Newton, Margaret A.; Thomson, Michael E.
The nature of dyslexia is defined and reviewed in the context of neurological and educational processes and the nature of a written language system. An illustrative case history of a typical dyslexic child is presented. The nature of a script system is examined in the light of current linguistic and psycholinguistic studies. Noted are…
Gabay, Yafit; Thiessen, Erik D.; Holt, Lori L.
Purpose: Developmental dyslexia (DD) is commonly thought to arise from phonological impairments. However, an emerging perspective is that a more general procedural learning deficit, not specific to phonological processing, may underlie DD. The current study examined if individuals with DD are capable of extracting statistical regularities across…
Jones, Manon W.; Branigan, Holly P.; Parra, Mario A.; Logie, Robert H.
The ability to learn visual-phonological associations is a unique predictor of word reading, and individuals with developmental dyslexia show impaired ability in learning these associations. In this study, we compared developmentally dyslexic and nondyslexic adults on their ability to form cross-modal associations (or "bindings") based…
Welsh, L W; Welsh, J J; Healy, M P
A group of dyslexic pupils with normal end organ function was studied by a central auditory battery to determine whether a hearing disability existed. The clinical features of dyslexia are presented with emphasis on the psychological developmental and functional disorders associated with this reading problem. The central battery of Willeford was selected as the test medium and the results of the 77 dyslexic students were compared to the normative data. The model proposed by Sparks, et al., is accepted as the mechanism for dichotic audition. Reference is made to the organic basis of reading disorders from lesion in the calcarine area to the angular gyrus. The competing sentence test, binaural fusion, rapidly alternating speech perception, and filtered speech are described in detail and are organic foundation for the study. The authors indentified a high rate of failure in this investigation. Over 50% of the dyslexic students failed two of the four tests, and each of the 77 failed at least one component. The most sensitive tests were binaural fusion and filtered speech with less variation from the norm in the remaining two components. The effect of maturation in central audition was measured in each of the four tests. The data suggest: 1. the scores are lower in the early ages in each test; 2. that rapidly alternating speech and competing sentences approach the normal range albeit somewhat delayed; and 3. that binaural fusion and filtered speech improve in score somewhat but rather moderately and never approach the normal range. Based upon the central auditory data and in conjunction with the anatomical pathways of vision, the authors suggest the site of lesion to be in the temporo-parietal cortex and the association fibers. PMID:7382713
Del Tufo, Stephanie N.; Myers, Emily B.
The comprehension of fluent speech in one's native language requires that listeners integrate the detailed acoustic-phonetic information available in the sound signal with linguistic knowledge. This interplay is especially apparent in the phoneme restoration effect, a phenomenon in which a missing phoneme is “restored” via the influence of top-down information from the lexicon and through bottom-up acoustic processing. Developmental dyslexia is a disorder characterized by an inability to read at the level of one's peers without any clear failure due to environmental influences. In the current study we utilized the phonemic restoration illusion paradigm to examine individual differences in phonemic restoration across a range of reading ability, from very good to dyslexic readers. Results demonstrate that restoration occurs less in those who have high scores on measures of phonological processing. Based on these results, we suggest that the processing or representation of acoustic detail may not be as reliable in poor and dyslexic readers, with the result that lexical information is more likely to override acoustic properties of the stimuli. This pattern of increased restoration could result from a failure of perceptual tuning, in which unstable representations of speech sounds result in the acceptance of non-speech sounds as speech. An additional or alternative theory is that degraded or impaired phonological processing at the speech sound level may reflect architecture that is overly plastic and consequently fails to stabilize appropriately for speech sound representations. Therefore, the inability to separate speech and noise may result as a deficit in separating noise from the acoustic signal. PMID:24926230
Del Tufo, Stephanie N; Myers, Emily B
The comprehension of fluent speech in one's native language requires that listeners integrate the detailed acoustic-phonetic information available in the sound signal with linguistic knowledge. This interplay is especially apparent in the phoneme restoration effect, a phenomenon in which a missing phoneme is "restored" via the influence of top-down information from the lexicon and through bottom-up acoustic processing. Developmental dyslexia is a disorder characterized by an inability to read at the level of one's peers without any clear failure due to environmental influences. In the current study we utilized the phonemic restoration illusion paradigm to examine individual differences in phonemic restoration across a range of reading ability, from very good to dyslexic readers. Results demonstrate that restoration occurs less in those who have high scores on measures of phonological processing. Based on these results, we suggest that the processing or representation of acoustic detail may not be as reliable in poor and dyslexic readers, with the result that lexical information is more likely to override acoustic properties of the stimuli. This pattern of increased restoration could result from a failure of perceptual tuning, in which unstable representations of speech sounds result in the acceptance of non-speech sounds as speech. An additional or alternative theory is that degraded or impaired phonological processing at the speech sound level may reflect architecture that is overly plastic and consequently fails to stabilize appropriately for speech sound representations. Therefore, the inability to separate speech and noise may result as a deficit in separating noise from the acoustic signal. PMID:24926230
Cui, Zaixu; Xia, Zhichao; Su, Mengmeng; Shu, Hua; Gong, Gaolang
Developmental dyslexia has been hypothesized to result from multiple causes and exhibit multiple manifestations, implying a distributed multidimensional effect on human brain. The disruption of specific white-matter (WM) tracts/regions has been observed in dyslexic children. However, it remains unknown if developmental dyslexia affects the human brain WM in a multidimensional manner. Being a natural tool for evaluating this hypothesis, the multivariate machine learning approach was applied in this study to compare 28 school-aged dyslexic children with 33 age-matched controls. Structural magnetic resonance imaging (MRI) and diffusion tensor imaging were acquired to extract five multitype WM features at a regional level: white matter volume, fractional anisotropy, mean diffusivity, axial diffusivity, and radial diffusivity. A linear support vector machine (LSVM) classifier achieved an accuracy of 83.61% using these MRI features to distinguish dyslexic children from controls. Notably, the most discriminative features that contributed to the classification were primarily associated with WM regions within the putative reading network/system (e.g., the superior longitudinal fasciculus, inferior fronto-occipital fasciculus, thalamocortical projections, and corpus callosum), the limbic system (e.g., the cingulum and fornix), and the motor system (e.g., the cerebellar peduncle, corona radiata, and corticospinal tract). These results were well replicated using a logistic regression classifier. These findings provided direct evidence supporting a multidimensional effect of developmental dyslexia on WM connectivity of human brain, and highlighted the involvement of WM tracts/regions beyond the well-recognized reading system in dyslexia. Finally, the discriminating results demonstrated a potential of WM neuroimaging features as imaging markers for identifying dyslexic individuals. PMID:26787263
Dyslexia is a common developmental learning difficulty, which persists throughout life. It is highly likely that those working in primary care will know, or even work with someone who has dyslexia. Dyslexia can impact on performance in postgraduate training and exams. The stereotypical characteristics of dyslexia, such as literacy difficulties, are often not obvious in adult learners. Instead, recognition requires a holistic approach to evaluating personal strengths and difficulties, in the context of a supportive relationship. Strategies to support dyslexic learners should consider recommendations made in formal diagnostic reports, and aim to address self-awareness and coping skills. PMID:27306461
Kirby, John R; Silvestri, Robert; Allingham, Beth H; Parrila, Rauno; La Fave, Chantal B
The present study describes the self-reported learning strategies and study approaches of college and university students with and without dyslexia and examines the relationship of those characteristics with reading ability. Students with (n = 36) and without (n = 66) dyslexia completed tests measuring reading rate, reading comprehension, reading history, learning strategies, and learning approaches. The results indicated that students without dyslexia obtained significantly higher scores than students with dyslexia in their reported use of selecting main ideas and test taking strategies. Students with dyslexia reported significantly greater use of study aids and time management strategies in comparison to students without dyslexia. Moreover, university students with dyslexia were significantly more likely to report a deep approach to learning in comparison to university students without dyslexia. Reading ability correlated positively with selecting main ideas and test taking strategies and negatively with use of study aids. The authors interpret the learning strategy results as consequences of and compensations for the difficulties that students with dyslexia have in word reading. PMID:18274505
van Viersen, Sietske; Kroesbergen, Evelyn H; Slot, Esther M; de Bree, Elise H
This study investigated how gifted children with dyslexia might be able to mask literacy problems and the role of possible compensatory mechanisms. The sample consisted of 121 Dutch primary school children that were divided over four groups (typically developing [TD] children, children with dyslexia, gifted children, gifted children with dyslexia). The test battery included measures of literacy (reading/spelling) and cognitive abilities related to literacy and language (phonological awareness [PA], rapid automatized naming [RAN], verbal short-term memory [VSTM], working memory [WM], grammar, and vocabulary). It was hypothesized that gifted children with dyslexia would outperform children with dyslexia on literacy tests. In addition, a core-deficit model including dyslexia-related weaknesses and a compensational model involving giftedness-related strengths were tested using Bayesian statistics to explain their reading/spelling performance. Gifted children with dyslexia performed on all literacy tests in between children with dyslexia and TD children. Their cognitive profile showed signs of weaknesses in PA and RAN and strengths in VSTM, WM, and language skills. Findings indicate that phonology is a risk factor for gifted children with dyslexia, but this is moderated by other skills such as WM, grammar, and vocabulary, providing opportunities for compensation of a cognitive deficit and masking of literacy difficulties. PMID:24935885
van der Leij, Aryan
Part of the Dutch Dyslexia Programme has been dedicated to early intervention. The question of whether the genetically affected learning mechanism of children who are at familial risk (FR) of developing dyslexia could be influenced by training phoneme awareness and letter-sound associations in the prereading phase was investigated. The rationale was that intervention studies reveal insights about the weaknesses of the learning mechanisms of FR children. In addition, the studies aimed to gather practical insights to be used in the development of a system of early diagnosis and prevention. Focused on the last period of kindergarten before formal reading instruction starts in Grade 1, intervention methods with comparable samples and designs but differences in delivery mode (use of computer or manual), tutor (semi-professional or parent), location (at school or at home), and additional practices (serial rapid naming or simple word reading) have been executed to test the hypothesis that the incidence and degree of dyslexia can be reduced. The present position paper summarizes the Dutch Dyslexia Programme findings and relates them to findings of other studies. It is discussed that the Dutch studies provide evidence on why prevention of dyslexia is hard to accomplish. It is argued that effective intervention should not only start early but also be adapted to the individual and often long-lasting educational needs of children at risk of reading failure. PMID:24133037
Firth, Nola; Frydenberg, Erica; Steeg, Charlotte; Bond, Lyndal
A dyslexia coping programme entitled "Success and Dyslexia" was implemented in two primary schools within a whole-class coping programme and whole-school dyslexia professional development context. One hundred and two year 6 students, 23 of whom had dyslexia, undertook surveys pretest, post-test and at 1-year follow-up. Effectiveness of the coping…
Carroll, Julia M.; Myers, Joanne M.
Comorbidity between SLI and dyslexia is well documented. Researchers have variously argued that dyslexia is a separate disorder from SLI, or that children with dyslexia show a subset of the difficulties shown in SLI. This study examines these hypotheses by assessing whether family history of dyslexia and speech and language difficulties are…
Helland, Turid; Plante, Elena; Hugdahl, Kenneth
This study focused on predicting dyslexia in children ahead of formal literacy training. Because dyslexia is a constitutional impairment, risk factors should be seen in preschool. It was hypothesized that data gathered at age 5 using questions targeting the dyslexia endophenotype should be reliable and valid predictors of dyslexia at age 11. A…
Tops, W.; Callens, C.; Van Cauwenberghe, E.; Adriaens, J.; Brysbaert, M.
To have a clearer idea of the problems students with dyslexia may face during their studies, we compared writings of 100 students with dyslexia and 100 age matched control students in higher education. The aim of this study was to compare the writing of young adults with dyslexia and young adults without dyslexia. The study was carried out in…
Wimmer, Heinz; Schurz, Matthias
This article summarizes our research on the manifestation of dyslexia in German and on cognitive deficits, which may account for the severe reading speed deficit and the poor orthographic spelling performance that characterize dyslexia in regular orthographies. An only limited causal role of phonological deficits (phonological awareness, phonological STM, and rapid naming) for the emergence of reading fluency and spelling deficits is inferred from two large longitudinal studies with assessments of phonology before learning to read. A review of our cross-sectional studies provides no support for several cognitive deficits (visual-attention deficit, magnocellular dysfunction, skill automatization deficit, and visual-sequential memory deficit), which were proposed as alternatives to the phonological deficit account. Finally, a revised version of the phonological deficit account in terms of a dysfunction in orthographic-phonological connectivity is proposed. PMID:20957684
Koeda, Tatsuya; Seki, Ayumi; Uchiyama, Hitoshi; Sadato, Norihiro
The aim of this report is to describe the characteristics of Japanese dyslexia, and to demonstrate several of our studies about the extraction of these characteristic and their neurophysiological and neuroimaging abnormalities, as well as advanced studies of phonological awareness and the underlying neural substrate. Based on these results, we have proposed a 2-step approach for remedial education (e-learning web site: http://www.dyslexia-koeda.jp/). The first step is decoding, which decreases reading errors, and the second is vocabulary learning, which improves reading fluency. This 2-step approach is designed to serve first grade children. In addition, we propose the RTI (response to intervention) model as a desirable system for remedial education. PMID:21146943
Friedmann, Naama; Tzailer-Gross, Lital; Gvion, Aviah
Individuals with text-based neglect dyslexia omit words on the neglected side of the sentence or text, usually on the left side. This study tested whether the syntactic structure of the target sentence affects reading in this type of neglect dyslexia. Because Hebrew is read from right to left, it enables testing whether the beginning of the…
Cline, Tony; Frederickson, Norah
Proposes how good practice can be developed in the assessment of dyslexia with bilingual children, presents evidence that language minorities are underrepresented in special programs, and highlights the value of recent approaches to defining dyslexia that do not depend on exclusionary criteria or on IQ-achievement discrepancy. (Author/VWL)
Glazzard, Jonathan; Dale, Kirsty
This paper tells the stories of two trainee teachers and their personal experiences of dyslexia. Both informants were English and training to be primary school teachers in England. Through drawing on their own experiences of education, the stories illustrate how dyslexia has shaped the self-concept, self-esteem and resilience of each informant.…
Chung, Kevin K. H.; Ho, Connie S. H.
Dyslexia appears to be the most prevalent disability of students with special educational needs in many mainstream classes, affecting around 9.7% of the school population in Hong Kong. The education of these students is therefore of great concern to the community. In the present paper research into dyslexia in the Chinese language is briefly…
van Viersen, Sietske; Kroesbergen, Evelyn H.; Slot, Esther M.; de Bree, Elise H.
This study investigated how gifted children with dyslexia might be able to mask literacy problems and the role of possible compensatory mechanisms. The sample consisted of 121 Dutch primary school children that were divided over four groups (typically developing [TD] children, children with dyslexia, gifted children, gifted children with…
The prevalence of phonological and surface dyslexia subtypes among Swedish university students with dyslexia (n = 40) was examined using both the regression method, developed by Castles and Coltheart, and latent profile analysis. When an academic-level control group was used as a reference group in a regression, eight students with phonological…
Serrano, Francisca; Defior, Sylvia
Dyslexia is a persistent problem in written language, consisting of a severe difficulty in word recognition. It is characterized by low reading performance, while other skills are not impaired, being normal or even superior in some cases. This paper reviews different proposals for defining and clarifying causes of dyslexia. Additionally, we…
Dyslexia, a difficult to define phenomenon, is manifested by the otherwise normal child who has an IQ above 90 and a reading subscore below the fifteenth percentile. Five observations about this phenomenon are: (1) The concept of dyslexia is often confused with "slowness" in learning to read. A child who is bright enough to guess instead of read…
Vagge, Aldo; Cavanna, Margherita; Traverso, Carlo Enrico; Iester, Michele
The aims of this study were to analyze the relationship between dyslexia and eye movements and to assess whether this method can be added to the workup of dyslexic patients. The sample was comprised of 11 children with a diagnosis of dyslexia and 11 normal between 8 and 13 years of age. All subjects underwent orthoptic evaluation, ophthalmological…
Gooch, Debbie; Hulme, Charles; Nash, Hannah M.; Snowling, Margaret J.
Background: Comorbidity among developmental disorders such as dyslexia, language impairment, attention deficit/hyperactivity disorder and developmental coordination disorder is common. This study explores comorbid weaknesses in preschool children at family risk of dyslexia with and without language impairment and considers the role that…
It has recently been suggested that dyslexia may manifest as a deficit in the neural synchrony underlying language-based codes (Goswami, 2011), such that the phonological deficits apparent in dyslexia occur as a consequence of poor synchronisation of oscillatory brain signals to the sounds of language. There is compelling evidence to support this suggestion, and it provides an intriguing new development in understanding the aetiology of dyslexia. It is undeniable that dyslexia is associated with poor phonological coding, however, reading is also a visual task, and dyslexia has also been associated with poor visual coding, particularly visuo-spatial sensitivity. It has been hypothesized for some time that specific frequency oscillations underlie visual perception. Although little research has been done looking specifically at dyslexia and cortical frequency oscillations, it is possible to draw on converging evidence from visual tasks to speculate that similar deficits could occur in temporal frequency oscillations in the visual domain in dyslexia. Thus, here the plausibility of a visual correlate of the Temporal Sampling Framework is considered, leading to specific hypotheses and predictions for future research. A common underlying neural mechanism in dyslexia, may subsume qualitatively different manifestations of reading difficulty, which is consistent with the heterogeneity of the disorder, and may open the door for a new generation of exciting research. PMID:24596549
Tops, Wim; Callens, Maaike; Bijn, Evi; Brysbaert, Marc
In this study we focused on the spelling of high-functioning students with dyslexia. We made a detailed classification of the errors in a word and sentence dictation task made by 100 students with dyslexia and 100 matched control students. All participants were in the first year of their bachelor's studies and had Dutch as mother tongue.…
Lam, Sutie S. T.; Au, Ricky K. C.; Leung, Howard W. H.; Li-Tsang, Cecilia W. P.
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…
Stampoltzis, Aglaia; Polychronopoulou, Stavroula
This paper reports a study exploring the personal and educational experiences of Greek students with dyslexia in higher education. Interviews with 16 students with dyslexia (11 male and five female) were conducted to investigate how they experienced school, peer relations, labelling, family support, university, self-esteem and how they made their…
Benasich, April A., Ed.; Fitch, R. Holly, Ed.
Understanding the precursors and early indicators of dyslexia is key to early identification and effective intervention. Now there's a single research volume that brings together the very latest knowledge on the earliest stages of dyslexia and the diverse genetic, neurobiological, and cognitive factors that may contribute to it. Based on findings…
Galaburda, Albert M.
For 25 years now, there has been a serious attempt to get at the fundamental cause(s) of dyslexia in our laboratory. A great deal of research has been carried out on the psychological and brain underpinnings of the linguistic dysfunctions seen in dyslexia, but attempts to get at its cause have been limited. Initially, observations were made on the…
Kirby, John R.; Silvestri, Robert; Allingham, Beth H.; Parrila, Rauno; La Fave, Chantal B.
The present study describes the self-reported learning strategies and study approaches of college and university students with and without dyslexia and examines the relationship of those characteristics with reading ability. Students with (n = 36) and without (n = 66) dyslexia completed tests measuring reading rate, reading comprehension, reading…
Anastasiou, Dimitris; Polychronopoulou, Stavroula
The present study analyzed identification procedures and explored the possibility of dyslexia overidentification in Greece. Data from various institutional sources provided evidence that the prevalence rate of dyslexia in the school population, aged 6-18, was slightly higher than 1%. Compared to the corresponding percentages from the United States…
Friedmann, Naama; Rahamim, Einav
Letter position dyslexia (LPD) is a peripheral dyslexia that causes errors of letter position within words, such as reading "cloud" as "could." In this study, we assessed the effect of various display manipulations and reading methods on the reading of 10 Hebrew readers with developmental LPD. These manipulations included…
Wright, Craig M.; Conlon, Elizabeth G.; Dyck, Murray
The aim of this study was to investigate the theory that visual magnocellular deficits seen in groups with dyslexia are linked to reading via the mechanisms of visual attention. Visual attention was measured with a serial search task and magnocellular function with a coherent motion task. A large group of children with dyslexia (n = 70) had slower…
Willburger, Edith; Landerl, Karin
In the anchoring deficit hypothesis of dyslexia ("Trends Cogn. Sci.", 2007; 11: 458-465), it is proposed that perceptual problems arise from the lack of forming a perceptual anchor for repeatedly presented stimuli. A study designed to explicitly test the specificity of the anchoring deficit for dyslexia is presented. Four groups, representing all…
Ho, Connie Suk-Han; Chan, David Wai-Ock; Lee, Suk-Han; Tsang, Suk-Man; Luan, Vivian Hui
The present study examined the cognitive profile and subtypes of developmental dyslexia in a nonalphabetic script, Chinese. One hundred and forty-seven Chinese primary school children with developmental dyslexia were tested on a number of literacy and cognitive tasks. The results showed that rapid naming deficit and orthographic deficit were the…
Schulte-Korne, Gerd; Ludwig, Kerstin U.; el Sharkawy, Jennifer; Nothen, Markus M.; Muller-Myhsok, Bertram; Hoffmann, Per
Our understanding of the causes of a developmental disorder like dyslexia has received recent input from both neuroscience and genetics. The discovery of 4 candidate genes for dyslexia and the identification of neuronal networks engaged when children read and spell are the basis for introducing this knowledge into education. However, the input…
Partanen, Marita; Fitzpatrick, Kevin; Madler, Burkhard; Edgell, Dorothy; Bjornson, Bruce; Giaschi, Deborah E.
The current study examined auditory processing deficits in dyslexia using a dichotic pitch stimulus and functional MRI. Cortical activation by the dichotic pitch task occurred in bilateral Heschl's gyri, right planum temporale, and right superior temporal sulcus. Adolescents with dyslexia, relative to age-matched controls, illustrated greater…
This article presents a theoretical overview at the cognitive level of the role of phonological awareness in reading development and developmental dyslexia across languages. It is argued that the primary deficit in developmental dyslexia in all languages lies in representing speech sounds: a deficit in phonological representation. (Contains…
Ziegler, Johannes C.
It has been commonly agreed that developmental dyslexia in different languages has a common biological origin: a dysfunction of left posterior temporal brain regions dealing with phonological processes. Siok, Perfetti, Jin, and Tan (2004, "Nature," 431, 71-76) challenge this biological unity theory of dyslexia: Chinese dyslexics show no deficits…
Patel, M.; Magnusson, M.; Lush, D.; Gomez, S.; Fransson, P. A.
Dyslexia has been shown to affect postural control. The aim of the present study was to investigate the difference in postural stability measured as torque variance in an adult dyslexic group (n=14, determined using the Adult Dyslexia Checklist (ADCL) and nonsense word repetition test) and an adult non-dyslexic group (n=39) on a firm surface and…
This article shares the author's research focusing on the facilitation of acting students with dyslexia in actor-training. For some individuals with dyslexia the translation of the written text into image-based symbols using technological modalities can play a crucial role to access and make concrete the meaning of the words; in this case…
The aim of this study was to see whether patterns of neuro-cognitive assets and deficits seen in dyslexia also would lead to different patterns of reading and writing. A group of dyslexic children was subgrouped by language comprehension and mathematics skills in accordance with the definition of the British Dyslexia Association of 1998. This…
Landerl, Karin; Fussenegger, Barbara; Moll, Kristina; Willburger, Edith
This study tests the hypothesis that dyslexia and dyscalculia are associated with two largely independent cognitive deficits, namely a phonological deficit in the case of dyslexia and a deficit in the number module in the case of dyscalculia. In four groups of 8- to 10-year-olds (42 control, 21 dyslexic, 20 dyscalculic, and 26…
Baillieux, Hanne; Vandervliet, Everhard J. M.; Manto, Mario; Parizel, Paul M.; De Deyn, Peter P.; Marien, Peter
Developmental dyslexia is the most common learning disability in school-aged children with an estimated incidence of five to ten percent. The cause and pathophysiological substrate of this developmental disorder is unclear. Recently, a possible involvement of the cerebellum in the pathogenesis of dyslexia has been postulated. In this study, 15…
What Works Clearinghouse, 2010
The "Dyslexia Training Program," developed at the Texas Scottish Rite Hospital for Children, is a Tier III reading intervention program that provides intensive phonics instruction to children with dyslexia, primarily in grades two through five. It is a comprehensive two-year program that bridges the gap for school districts in which a trained…
McArthur, Genevieve; Castles, Anne; Kohnen, Saskia; Larsen, Linda; Jones, Kristy; Anandakumar, Thushara; Banales, Erin
The aims of this study were to (a) compare sight word training and phonics training in children with dyslexia, and (b) determine if different orders of sight word and phonics training have different effects on the reading skills of children with dyslexia. One group of children (n = 36) did 8 weeks of phonics training (reading via grapheme-phoneme…
Rubinsten, Orly; Henik, Avishai
This work examines the association between symbols and their representation in adult developmental dyscalculia and dyslexia. Experiment 1 used comparative judgment of numerals, and it was found that in physical comparisons (e.g., 3-5 vs. 3-5) the dyscalculia group showed a significantly smaller congruity effect than did the dyslexia and the…
Farmer, Marian; Riddick, Barbara; Sterling, Christopher
This book addresses issues in the inclusion of students with dyslexia in programs of higher education in the United Kingdom. Chapter 1 examines debates around assessing students with dyslexia and urges a "modular" approach. Chapter 2 looks at assessment of areas of impairment traditionally considered to be dyslexic. Chapter 3 considers…
Brunswick, Nicola; Martin, G. Neil; Marzano, Lisa
Anecdotal evidence indicates that dyslexia is positively associated with superior visuospatial ability but empirical evidence is inconsistent. We explicitly tested the hypothesis that dyslexia is associated with visuospatial advantage in 20 dyslexic and 21 unimpaired adult readers using paper-and-pencil measures and tests of "everyday"…
Tilanus, Elisabeth A T; Segers, Eliane; Verhoeven, Ludo
We examined the responsiveness to a 12-week phonics intervention in 54 s-grade Dutch children with dyslexia, and compared their reading and spelling gains to a control group of 61 typical readers. The intervention aimed to train grapheme-phoneme correspondences (GPCs), and word reading and spelling by using phonics instruction. We examined the accuracy and efficiency of grapheme-phoneme correspondences, decoding words and pseudowords, as well as the accuracy of spelling words before and after the intervention. Moreover, responsiveness to intervention was examined by studying to what extent scores at posttest could directly or indirectly be predicted from precursor measures. Results showed that the children with dyslexia were significantly behind in all reading and spelling measures at pretest. During the intervention, the children with dyslexia made more progress on GPC, (pseudo)word decoding accuracy and efficiency, and spelling accuracy than the typical reading group. Furthermore, we found a direct effect of the precursor measures rapid automatized naming, verbal working memory and phoneme deletion on the dyslexic children's progress in GPC speed, and indirect effects of rapid automatized naming and phoneme deletion on word and pseudoword efficiency and word decoding accuracy via the scores at pretest. Copyright © 2016 John Wiley & Sons, Ltd. PMID:27465208
Yang, Ying-Hui; Yang, Yang; Chen, Bao-Guo; Zhang, Yi-Wei; Bi, Hong-Yan
The cerebellar deficit hypothesis for developmental dyslexia claims that cerebellar dysfunction causes the failures in the acquisition of visuomotor skills and automatic reading and writing skills. In people with dyslexia in the alphabetic languages, the abnormal activation and structure of the right or bilateral cerebellar lobes have been identified. Using a typical implicit motor learning task, however, one neuroimaging study demonstrated the left cerebellar dysfunction in Chinese children with dyslexia. In the present study, using voxel-based morphometry, we found decreased gray matter volume in the left cerebellum in Chinese children with dyslexia relative to age-matched controls. The positive correlation between reading performance and regional gray matter volume suggests that the abnormal structure in the left cerebellum is responsible for reading disability in Chinese children with dyslexia. PMID:27047403
Yang, Yang; Chen, Bao-Guo; Zhang, Yi-Wei; Bi, Hong-Yan
The cerebellar deficit hypothesis for developmental dyslexia claims that cerebellar dysfunction causes the failures in the acquisition of visuomotor skills and automatic reading and writing skills. In people with dyslexia in the alphabetic languages, the abnormal activation and structure of the right or bilateral cerebellar lobes have been identified. Using a typical implicit motor learning task, however, one neuroimaging study demonstrated the left cerebellar dysfunction in Chinese children with dyslexia. In the present study, using voxel-based morphometry, we found decreased gray matter volume in the left cerebellum in Chinese children with dyslexia relative to age-matched controls. The positive correlation between reading performance and regional gray matter volume suggests that the abnormal structure in the left cerebellum is responsible for reading disability in Chinese children with dyslexia. PMID:27047403
Peter, Varghese; Kalashnikova, Marina; Burnham, Denis
This study aimed to investigate how children with dyslexia weight amplitude rise time (ART) and formant rise time (FRT) cues in phonetic discrimination. Passive mismatch responses (MMR) were recorded for a/ba/-/wa/contrast in a multiple deviant odd-ball paradigm to identify the neural response to cue weighting in 17 children with dyslexia and 17 age-matched control children. The deviant stimuli had either partial or full ART or FRT cues. The results showed that ART did not generate an MMR in either group, whereas both partial and full FRT cues generated MMR in control children while only full FRT cues generated MMR in children with dyslexia. These findings suggest that children, both controls and those with dyslexia, discriminate speech based on FRT cues and not ART cues. However, control children have greater sensitivity to FRT cues in speech compared to children with dyslexia. PMID:27017263
Geiser, Eveline; Kjelgaard, Margaret; Christodoulou, Joanna A.; Cyr, Abigail; Gabrieli, John D. E.
Reading disability in children with dyslexia has been proposed to reflect impairment in auditory timing perception. We investigated one aspect of timing perception--"temporal grouping"--as present in prosodic phrase boundaries of natural speech, in age-matched groups of children, ages 6-8 years, with and without dyslexia. Prosodic phrase…
Zeffiro, Thomas J.; Eden, Guinevere
This article reviews recent evidence supporting a biological basis for developmental dyslexia. It concludes that the combined evidence demonstrating macroscopic morphologic, microscopic neuronal, and microstructural white matter abnormalities in dyslexia is consistent with a localization of the principle pathophysicological process to perisylvian…
Tamboer, Peter; Scholte, H. Steven; Vorst, Harrie C. M.
In voxel-based morphometry studies of dyslexia, the relation between causal theories of dyslexia and gray matter (GM) and white matter (WM) volume alterations is still under debate. Some alterations are consistently reported, but others failed to reach significance. We investigated GM alterations in a large sample of Dutch students (37 dyslexics…
Smith-Spark, James H; Zięcik, Adam P; Sterling, Christopher
Prospective memory (PM) is memory for delayed intentions. Despite its importance to everyday life, the few studies on PM function in adults with dyslexia which exist have relied on self-report measures. To determine whether self-reported PM deficits can be measured objectively, laboratory-based PM tasks were administered to 24 adults with dyslexia and 25 age- and IQ-matched adults without dyslexia. Self-report data indicated that people with dyslexia felt that time-based PM (TBPM; requiring responses at certain times in the future) was most problematic for them and so this form of PM was the focus of investigation. Whilst performing the ongoing task from which they were required to break out every 3 min to make a PM-related response, the participants were allowed to make clock checks whenever they wished. The cognitive demands made on ongoing behaviour were manipulated to determine whether loading executive resources had a mediating role in dyslexia-related deficits in PM, resulting in three tasks with varying working memory load. A semi-naturalistic TBPM task was also administered, in which the participants were asked to remind the experimenter to save a data file 40 min after being given this instruction. Dyslexia-related differences were found across all three computerized tasks, regardless of cognitive load. The adults with dyslexia made fewer correct PM responses and also fewer clock checks. On the semi-naturalistic task, the participants with dyslexia were less likely to remember to remind the experimenter to save the file. This is the first study to document PM deficits in dyslexia using objective measures of performance. Since TBPM impairments were found under more naturalistic conditions as well as on computerized tasks, the results have implications for workplace support for adults with dyslexia. PMID:26649894
Hu, Wei; Lee, Hwee Ling; Zhang, Qiang; Liu, Tao; Geng, Li Bo; Seghier, Mohamed L.; Shakeshaft, Clare; Twomey, Tae; Green, David W.; Yang, Yi Ming; Price, Cathy J.
Previous neuroimaging studies have suggested that developmental dyslexia has a different neural basis in Chinese and English populations because of known differences in the processing demands of the Chinese and English writing systems. Here, using functional magnetic resonance imaging, we provide the first direct statistically based investigation…
Lorusso, Maria Luisa; Cantiani, Chiara; Molteni, Massimo
The nature of Rapid Auditory Processing (RAP) deficits in dyslexia remains debated, together with the specificity of the problem to certain types of stimuli and/or restricted subgroups of individuals. Following the hypothesis that the heterogeneity of the dyslexic population may have led to contrasting results, the aim of the study was to define the effect of age, dyslexia subtype and comorbidity on the discrimination and reproduction of non-verbal tone sequences. Participants were 46 children aged 8–14 (26 with dyslexia, subdivided according to age, presence of a previous language delay, and type of dyslexia). Experimental tasks were a Temporal Order Judgment (TOJ) (manipulating tone length, ISI and sequence length), and a Pattern Discrimination Task. Dyslexic children showed general RAP deficits. Tone length and ISI influenced dyslexic and control children's performance in a similar way, but dyslexic children were more affected by an increase from 2 to 5 sounds. As to age, older dyslexic children's difficulty in reproducing sequences of 4 and 5 tones was similar to that of normally reading younger (but not older) children. In the analysis of subgroup profiles, the crucial variable appears to be the advantage, or lack thereof, in processing long vs. short sounds. Dyslexic children with a previous language delay obtained the lowest scores in RAP measures, but they performed worse with shorter stimuli, similar to control children, while dyslexic-only children showed no advantage for longer stimuli. As to dyslexia subtype, only surface dyslexics improved their performance with longer stimuli, while phonological dyslexics did not. Differential scores for short vs. long tones and for long vs. short ISIs predict non-word and word reading, respectively, and the former correlate with phonemic awareness. In conclusion, the relationship between non-verbal RAP, phonemic skills and reading abilities appears to be characterized by complex interactions with subgroup
Bishop-Liebler, Paula; Welch, Graham; Huss, Martina; Thomson, Jennifer M; Goswami, Usha
The core cognitive difficulty in developmental dyslexia involves phonological processing, but adults and children with dyslexia also have sensory impairments. Impairments in basic auditory processing show particular links with phonological impairments, and recent studies with dyslexic children across languages reveal a relationship between auditory temporal processing and sensitivity to rhythmic timing and speech rhythm. As rhythm is explicit in music, musical training might have a beneficial effect on the auditory perception of acoustic cues to rhythm in dyslexia. Here we took advantage of the presence of musicians with and without dyslexia in musical conservatoires, comparing their auditory temporal processing abilities with those of dyslexic non-musicians matched for cognitive ability. Musicians with dyslexia showed equivalent auditory sensitivity to musicians without dyslexia and also showed equivalent rhythm perception. The data support the view that extensive rhythmic experience initiated during childhood (here in the form of music training) can affect basic auditory processing skills which are found to be deficient in individuals with dyslexia. PMID:25044949
Ma, Yizhou; Koyama, Maki S.; Milham, Michael P.; Castellanos, F. Xavier; Quinn, Brian T.; Pardoe, Heath; Wang, Xiuyuan; Kuzniecky, Ruben; Devinsky, Orrin; Thesen, Thomas; Blackmon, Karen
Abnormalities in cortical structure are commonly observed in children with dyslexia in key regions of the “reading network.” Whether alteration in cortical features reflects pathology inherent to dyslexia or environmental influence (e.g., impoverished reading experience) remains unclear. To address this question, we compared MRI-derived metrics of cortical thickness (CT), surface area (SA), gray matter volume (GMV), and their lateralization across three different groups of children with a historical diagnosis of dyslexia, who varied in current reading level. We compared three dyslexia subgroups with: (1) persistent reading and spelling impairment; (2) remediated reading impairment (normal reading scores), and (3) remediated reading and spelling impairments (normal reading and spelling scores); and a control group of (4) typically developing children. All groups were matched for age, gender, handedness, and IQ. We hypothesized that the dyslexia group would show cortical abnormalities in regions of the reading network relative to controls, irrespective of remediation status. Such a finding would support that cortical abnormalities are inherent to dyslexia and are not a consequence of abnormal reading experience. Results revealed increased CT of the left fusiform gyrus in the dyslexia group relative to controls. Similarly, the dyslexia group showed CT increase of the right superior temporal gyrus, extending into the planum temporale, which resulted in a rightward CT asymmetry on lateralization indices. There were no group differences in SA, GMV, or their lateralization. These findings held true regardless of remediation status. Each reading level group showed the same “double hit” of atypically increased left fusiform CT and rightward superior temporal CT asymmetry. Thus, findings provide evidence that a developmental history of dyslexia is associated with CT abnormalities, independent of remediation status. PMID:25610779
Schneps, Matthew H.; Brockmole, J. R.; Rose, L. T.; Pomplun, M.; Sonnert, G.; Greenhill, L. J.
Dyslexia is a hereditary neurological condition characterized by difficulties in reading, writing, and spelling. The fact that those with dyslexia include many accomplished scientists, including some recognized with a Nobel Prize, has prompted researchers to suggest that the neurology of dyslexia may predispose these individuals to advantages in visually-intensive domains such as science. Here, we report evidence of a link between dyslexia and abilities for visual processing useful in astronomy. First, we show that when images of natural scenes are Gaussian-blurred, so as to remove high-frequency detail (and resemble many astronomical images), college students with dyslexia significantly outperform those who are typical readers in learning the spatial contexts presented. Second, we show that when the threshold ability to detect radio signatures characteristic of black holes is measured in a laboratory simulation, astrophysicists with dyslexia significantly outperform those who are typical readers in this task when the visual periphery is important. In a third experiment, using eye-tracking technologies, we demonstrate that visual strategies significantly correlate with success in the black hole task, but that college students with dyslexia tend not to employ the strategies most likely to lead to success. Collectively, these studies suggest that dyslexia is linked to neurological advantages useful in astronomical careers, but that left to their own devices students with dyslexia may not benefit from these advantages without practice or training. These studies imply that many students who are struggling to read may find successful careers in astronomy or other fields that build on visual advantages linked to their reading disability, but that education and training may be vital in helping these students realize their strengths. This material is based upon work supported by the George E. Burch Fellowship (Smithsonian Institution) and the National Science Foundation
Recent years have seen the publication of a range of new theories suggesting that the basis of dyslexia might be sensory dysfunction. In this Opinion article, the evidence for and against several prominent sensory theories of dyslexia is closely scrutinized. Contrary to the causal claims being made, my analysis suggests that many proposed sensory deficits might result from the effects of reduced reading experience on the dyslexic brain. I therefore suggest that longitudinal studies of sensory processing, beginning in infancy, are required to successfully identify the neural basis of developmental dyslexia. Such studies could have a powerful impact on remediation. PMID:25370786
Charfi, Afifa; Ben Hadj Yahia, Sihem; Kharrat, Salima; Zouari, Mourad; Bouchama, Jihen; Naziha, Khouja; Abdelmajid, Larnaout; Hentati, Fayçal; Hachicha, Slah
Dyslexia is a reading problem disorder. It can be a direct result of epilepsia for some kids. The researchers have done the study on 30 school kids that suffer from epilepsia. All the children had Audiometry which was normal in all cases. The orthophonic exam has done in all cases, founding a prononciation and speaker disorder also there is disorder at the psychometric test The purpose of the study research is to define the different profiles of dyslexia on the epileptics, then to check the importance of collaboration between Otorhinolaryngologists, Neurologists and Orthophonists to take care of the epileptic kids having dyslexia. PMID:17288285
Chiarenza, Giuseppe Augusto
Goal directed behavior is explained by two approaches: the first, which can be named as cybertetic (behavior is wieved as homeostatic and reflexive), and second, as cognitive approach, a learned response, (skills developed by whaching the behavior of another individual). The aim of the paper is to present a noninvasive method described as an interaction of human beings with environment, recording the electrical activity of the brain from the human scalp. Obtained results are in agreement of psychological theories that place at determined levels of age the acquisition of the capacities of abstract thinking and with the functional neuroanatomic studies according to which biological maturation is necessary for learning processes to develop. An acquired level of learning is in close relationship with the maturation level of the cerebral structures. PMID:27442417
Ziegler, Johannes C; Pech-Georgel, Catherine; George, Florence; Foxton, Jessica M
This study investigated global versus local pitch pattern perception in children with dyslexia aged between 8 and 11 years. Children listened to two consecutive 4-tone pitch sequences while performing a same/different task. On the different trials, sequences either preserved the contour (local condition) or they violated the contour (global condition). Compared to normally developing children, dyslexics showed robust pitch perception deficits in the local but not the global condition. This finding was replicated in a simple pitch direction task, which minimizes sequencing and short term memory. Results are consistent with a left-hemisphere deficit in dyslexia because local pitch changes are supposedly processed by the left hemisphere, whereas global pitch changes are processed by the right hemisphere. The present data suggest a link between impaired pitch processing and abnormal phonological development in children with dyslexia, which makes pitch pattern processing a potent tool for early diagnosis and remediation of dyslexia. PMID:22204845