Visual processing of multiple elements in the dyslexic brain: evidence for a superior parietal dysfunction

PubMed Central

Lobier, Muriel A.; Peyrin, Carole; Pichat, Cédric; Le Bas, Jean-François; Valdois, Sylviane

2014-01-01

The visual attention (VA) span deficit hypothesis of developmental dyslexia posits that impaired multiple element processing can be responsible for poor reading outcomes. In VA span impaired dyslexic children, poor performance on letter report tasks is associated with reduced parietal activations for multiple letter processing. While this hints towards a non-specific, attention-based dysfunction, it is still unclear whether reduced parietal activity generalizes to other types of stimuli. Furthermore, putative links between reduced parietal activity and reduced ventral occipito-temporal (vOT) in dyslexia have yet to be explored. Using functional magnetic resonance imaging, we measured brain activity in 12 VA span impaired dyslexic adults and 12 adult skilled readers while they carried out a categorization task on single or multiple alphanumeric or non-alphanumeric characters. While healthy readers activated parietal areas more strongly for multiple than single element processing (right-sided for alphanumeric and bilateral for non-alphanumeric), similar stronger multiple element right parietal activations were absent for dyslexic participants. Contrasts between skilled and dyslexic readers revealed significantly reduced right superior parietal lobule (SPL) activity for dyslexic readers regardless of stimuli type. Using a priori anatomically defined regions of interest, we showed that neural activity was reduced for dyslexic participants in both SPL and vOT bilaterally. Finally, we used multiple regressions to test whether SPL activity was related to vOT activity in each group. In the left hemisphere, SPL activity covaried with vOT activity for both normal and dyslexic readers. In contrast, in the right hemisphere, SPL activity covaried with vOT activity only for dyslexic readers. These results bring critical support to the VA interpretation of the VA Span deficit. In addition, they offer a new insight on how deficits in automatic vOT based word recognition could arise in developmental dyslexia. PMID:25071509

Overcoming Dyslexia in Children, Adolescents, and Adults. Third Edition.

ERIC Educational Resources Information Center

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.…

An Interpretative Model of Early Indicators of Specific Developmental Dyslexia in Preschool Age: A Comparative Presentation of Three Studies in Greece

ERIC Educational Resources Information Center

Zakopoulou, Victoria; Anagnostopoulou, Areti; Christodoulides, Pavlos; Stavrou, Lambros; Sarri, Ioanna; Mavreas, Venetsanos; Tzoufi, Meropi

2011-01-01

The detection of specific factors of the developmental dyslexia at an early stage, and the identification of the role of those factors responsible for its manifestation, is a fundamental area of study on dyslexia in the recent literature. The objective of the present study is to clarify that dysfunctions in the following specific domains…

Impaired recognition of faces and objects in dyslexia: Evidence for ventral stream dysfunction?

PubMed

Sigurdardottir, Heida Maria; Ívarsson, Eysteinn; Kristinsdóttir, Kristjana; Kristjánsson, Árni

2015-09-01

The objective of this study was to establish whether or not dyslexics are impaired at the recognition of faces and other complex nonword visual objects. This would be expected based on a meta-analysis revealing that children and adult dyslexics show functional abnormalities within the left fusiform gyrus, a brain region high up in the ventral visual stream, which is thought to support the recognition of words, faces, and other objects. 20 adult dyslexics (M = 29 years) and 20 matched typical readers (M = 29 years) participated in the study. One dyslexic-typical reader pair was excluded based on Adult Reading History Questionnaire scores and IS-FORM reading scores. Performance was measured on 3 high-level visual processing tasks: the Cambridge Face Memory Test, the Vanderbilt Holistic Face Processing Test, and the Vanderbilt Expertise Test. People with dyslexia are impaired in their recognition of faces and other visually complex objects. Their holistic processing of faces appears to be intact, suggesting that dyslexics may instead be specifically impaired at part-based processing of visual objects. The difficulty that people with dyslexia experience with reading might be the most salient manifestation of a more general high-level visual deficit. (c) 2015 APA, all rights reserved).

Perspectives on dyslexia

PubMed Central

Siegel, Linda S

2006-01-01

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

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

PubMed Central

Berninger, Virginia; Richards, Todd

2010-01-01

Cross-country, longitudinal twin studies provide strong evidence for both the biological and environmental basis of dyslexia, and the stability of genetic influences on reading and spelling, even when skills improve in response to instruction. Although DNA studies aimed at identifying gene candidates in dyslexia and related phenotypes (behavioral expression of underlying genotypes); and imaging studies of brain differences between individuals with and without dyslexia and the brain’s response to instructional treatment are increasing, this review illustrates, with the findings of one multidisciplinary research center, an emerging trend to investigate the inter-relationships among genetic, brain and instructional treatment findings in the same sample, which are interpreted in reference to a working-memory architecture, for dyslexia (impaired decoding and spelling) and/or dysgraphia (impaired handwriting). General principles for diagnosis and treatment, based on research with children who failed to respond to the regular instructional program, are summarized for children meeting research criteria for having or being at risk for dyslexia or dysgraphia. Research documenting earlier emerging specific oral language impairment during preschool years associated with reading and writing disabilities during school years is also reviewed. Recent seminal advances and projected future trends are discussed for linking brain endophenotypes and gene candidates, identifying transchromosomal interactions, and exploring epigenetics (chemic al modifications of gene expression in response to developmental or environmental changes). Rather than providing final answers, this review highlights past, current and emerging issues in dyslexia research and practice. PMID:20953351

Understanding Dyslexia. Learning Times. Volume 8, Number 2, Spring 2010

ERIC Educational Resources Information Center

LDA Minnesota, 2010

2010-01-01

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…

P300 Event-Related Potentials in Children with Dyslexia

ERIC Educational Resources Information Center

Papagiannopoulou, Eleni A.; Lagopoulos, Jim

2017-01-01

To elucidate the timing and the nature of neural disturbances in dyslexia and to further understand the topographical distribution of these, we examined entire brain regions employing the non-invasive auditory oddball P300 paradigm in children with dyslexia and neurotypical controls. Our findings revealed abnormalities for the dyslexia group in…

Genetic dyslexia risk variant is related to neural connectivity patterns underlying phonological awareness in children.

PubMed

Skeide, Michael A; Kirsten, Holger; Kraft, Indra; Schaadt, Gesa; Müller, Bent; Neef, Nicole; Brauer, Jens; Wilcke, Arndt; Emmrich, Frank; Boltze, Johannes; Friederici, Angela D

2015-09-01

Phonological awareness is the best-validated predictor of reading and spelling skill and therefore highly relevant for developmental dyslexia. Prior imaging genetics studies link several dyslexia risk genes to either brain-functional or brain-structural factors of phonological deficits. However, coherent evidence for genetic associations with both functional and structural neural phenotypes underlying variation in phonological awareness has not yet been provided. Here we demonstrate that rs11100040, a reported modifier of SLC2A3, is related to the functional connectivity of left fronto-temporal phonological processing areas at resting state in a sample of 9- to 12-year-old children. Furthermore, we provide evidence that rs11100040 is related to the fractional anisotropy of the arcuate fasciculus, which forms the structural connection between these areas. This structural connectivity phenotype is associated with phonological awareness, which is in turn associated with the individual retrospective risk scores in an early dyslexia screening as well as to spelling. These results suggest a link between a dyslexia risk genotype and a functional as well as a structural neural phenotype, which is associated with a phonological awareness phenotype. The present study goes beyond previous work by integrating genetic, brain-functional and brain-structural aspects of phonological awareness within a single approach. These combined findings might be another step towards a multimodal biomarker for developmental dyslexia. Copyright © 2015 Elsevier Inc. All rights reserved.

Dyslexia: Neuroanatomical/Neurolinguistic Perspectives.

ERIC Educational Resources Information Center

Hynd, George W.; Hynd, Cynthia R.

1984-01-01

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)

Brain basis of phonological awareness for spoken language in children and its disruption in dyslexia.

PubMed

Kovelman, Ioulia; Norton, Elizabeth S; Christodoulou, Joanna A; Gaab, Nadine; Lieberman, Daniel A; Triantafyllou, Christina; Wolf, Maryanne; Whitfield-Gabrieli, Susan; Gabrieli, John D E

2012-04-01

Phonological awareness, knowledge that speech is composed of syllables and phonemes, is critical for learning to read. Phonological awareness precedes and predicts successful transition from language to literacy, and weakness in phonological awareness is a leading cause of dyslexia, but the brain basis of phonological awareness for spoken language in children is unknown. We used functional magnetic resonance imaging to identify the neural correlates of phonological awareness using an auditory word-rhyming task in children who were typical readers or who had dyslexia (ages 7-13) and a younger group of kindergarteners (ages 5-6). Typically developing children, but not children with dyslexia, recruited left dorsolateral prefrontal cortex (DLPFC) when making explicit phonological judgments. Kindergarteners, who were matched to the older children with dyslexia on standardized tests of phonological awareness, also recruited left DLPFC. Left DLPFC may play a critical role in the development of phonological awareness for spoken language critical for reading and in the etiology of dyslexia.

Space, Time, and Dyslexia: Central Nervous System Factors in Reading Disability.

ERIC Educational Resources Information Center

Krippner, Stanley

Developmental and post-traumatic dyslexia are discussed in terms of a dysfunction of the central nervous system resulting in reading disabilities. The relationship of reading to other language functions is considered, with emphasis on the temporal aspects of speech and reading. An interdisciplinary approach is held necessary for the diagnosis of…

Investigation of Abnormal Left Temporal Functioning in Dyslexia through rCBF, Auditory Evoked Potentials, and Positron Emission Tomography.

ERIC Educational Resources Information Center

Wood, Frank; And Others

1991-01-01

Investigates the proposed left hemisphere dysfunction in dyslexia by reviewing four studies using regional cerebral blood flow (RCBF) and combined auditory evoked responses with positron emission tomography. Emphasizes methodological issues. Finds that dyslexics showed a positive correlation between Heschl's gyrus activation and phonemic…

The Double-Deficit Hypothesis: A Comprehensive Analysis of the Evidence

ERIC Educational Resources Information Center

Vukovic, Rose K.; Siegel, Linda S.

2006-01-01

The double-deficit hypothesis of developmental dyslexia proposes that deficits in phonological processing and naming speed represent independent sources of dysfunction in dyslexia. The present article is a review of the evidence for the double-deficit hypothesis, including a discussion of recent findings related to the hypothesis. Studies in this…

Brain Hemisphericity and Developmental Dyslexia

ERIC Educational Resources Information Center

Vlachos, Filippos; Andreou, Eleni; Delliou, Afroditi

2013-01-01

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…

Reading Disorders in Primary Progressive Aphasia: A Behavioral and Neuroimaging Study

ERIC Educational Resources Information Center

Brambati, S. M.; Ogar, J.; Neuhaus, J.; Miller, B. L.; Gorno-Tempini, M. L.

2009-01-01

Previous neuropsychological studies on acquired dyslexia revealed a double dissociation in reading impairments. Patients with phonological dyslexia have selective difficulty in reading pseudo-words, while those with surface dyslexia misread exception words. This double dissociation in reading abilities has often been reported in brain-damaged…

Balancing and Pointing Tasks in Dyslexic and Control Adults

ERIC Educational Resources Information Center

Stoodley, Catherine J.; Fawcett, Angela J.; Nicolson, Roderick I.; Stein, John F.

2006-01-01

Developmental dyslexia may affect as much as 15% of the population, but the aetiology of the disorder is still being debated. The cerebellar theory of dyslexia proposes that cerebellar dysfunction could lead to the myriad of symptoms seen in dyslexic individuals, both in literacy and non-literacy domains. The cerebellum is crucial to the fluent…

Brain Responses to Lexical-Semantic Priming in Children At-Risk for Dyslexia

ERIC Educational Resources Information Center

Torkildsen, Janne von Koss; Syversen, Gro; Simonsen, Hanne Gram; Moen, Inger; Lindgren, Magnus

2007-01-01

Deviances in early event-related potential (ERP) components reflecting auditory and phonological processing are well-documented in children at familial risk for dyslexia. However, little is known about brain responses which index processing in other linguistic domains such as lexicon, semantics and syntax in this group. The present study…

Developmental dyslexia in Chinese and English populations: dissociating the effect of dyslexia from language differences

PubMed Central

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

2010-01-01

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 into how the effect of dyslexia on brain activation is influenced by the Chinese and English writing systems. Brain activation for semantic decisions on written words was compared in English dyslexics, Chinese dyslexics, English normal readers and Chinese normal readers, while controlling for all other experimental parameters. By investigating the effects of dyslexia and language in one study, we show common activation in Chinese and English dyslexics despite different activation in Chinese versus English normal readers. The effect of dyslexia in both languages was observed as less than normal activation in the left angular gyrus and in left middle frontal, posterior temporal and occipitotemporal regions. Differences in Chinese and English normal reading were observed as increased activation for Chinese relative to English in the left inferior frontal sulcus; and increased activation for English relative to Chinese in the left posterior superior temporal sulcus. These cultural differences were not observed in dyslexics who activated both left inferior frontal sulcus and left posterior superior temporal sulcus, consistent with the use of culturally independent strategies when reading is less efficient. By dissociating the effect of dyslexia from differences in Chinese and English normal reading, our results reconcile brain activation results with a substantial body of behavioural studies showing commonalities in the cognitive manifestation of dyslexia in Chinese and English populations. They also demonstrate the influence of cognitive ability and learning environment on a common neural system for reading. PMID:20488886

Developmental dyslexia in Chinese and English populations: dissociating the effect of dyslexia from language differences.

PubMed

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

2010-06-01

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 into how the effect of dyslexia on brain activation is influenced by the Chinese and English writing systems. Brain activation for semantic decisions on written words was compared in English dyslexics, Chinese dyslexics, English normal readers and Chinese normal readers, while controlling for all other experimental parameters. By investigating the effects of dyslexia and language in one study, we show common activation in Chinese and English dyslexics despite different activation in Chinese versus English normal readers. The effect of dyslexia in both languages was observed as less than normal activation in the left angular gyrus and in left middle frontal, posterior temporal and occipitotemporal regions. Differences in Chinese and English normal reading were observed as increased activation for Chinese relative to English in the left inferior frontal sulcus; and increased activation for English relative to Chinese in the left posterior superior temporal sulcus. These cultural differences were not observed in dyslexics who activated both left inferior frontal sulcus and left posterior superior temporal sulcus, consistent with the use of culturally independent strategies when reading is less efficient. By dissociating the effect of dyslexia from differences in Chinese and English normal reading, our results reconcile brain activation results with a substantial body of behavioural studies showing commonalities in the cognitive manifestation of dyslexia in Chinese and English populations. They also demonstrate the influence of cognitive ability and learning environment on a common neural system for reading.

Enhancement of brain event-related potentials to speech sounds is associated with compensated reading skills in dyslexic children with familial risk for dyslexia.

PubMed

Lohvansuu, Kaisa; Hämäläinen, Jarmo A; Tanskanen, Annika; Ervast, Leena; Heikkinen, Elisa; Lyytinen, Heikki; Leppänen, Paavo H T

2014-12-01

Specific reading disability, dyslexia, is a prevalent and heritable disorder impairing reading acquisition characterized by a phonological deficit. However, the underlying mechanism of how the impaired phonological processing mediates resulting dyslexia or reading disabilities remains still unclear. Using ERPs we studied speech sound processing of 30 dyslexic children with familial risk for dyslexia, 51 typically reading children with familial risk for dyslexia, and 58 typically reading control children. We found enhanced brain responses to shortening of a phonemic length in pseudo-words (/at:a/ vs. /ata/) in dyslexic children with familial risk as compared to other groups. The enhanced brain responses were associated with better performance in behavioral phonemic length discrimination task, as well as with better reading and writing accuracy. Source analyses revealed that the brain responses of sub-group of dyslexic children with largest responses originated from a more posterior area of the right temporal cortex as compared to the responses of the other participants. This is the first electrophysiological evidence for a possible compensatory speech perception mechanism in dyslexia. The best readers within the dyslexic group have probably developed alternative strategies which employ compensatory mechanisms substituting their possible earlier deficit in phonological processing and might therefore be able to perform better in phonemic length discrimination and reading and writing accuracy tasks. However, we speculate that for reading fluency compensatory mechanisms are not that easily built and dyslexic children remain slow readers during their adult life. Copyright © 2014 Elsevier B.V. All rights reserved.

Morphological differences in the lateral geniculate nucleus associated with dyslexia

PubMed Central

Giraldo-Chica, Mónica; Hegarty, John P.; Schneider, Keith A.

2015-01-01

Developmental dyslexia is a common learning disability characterized by normal intelligence but difficulty in skills associated with reading, writing and spelling. One of the most prominent, albeit controversial, theories of dyslexia is the magnocellular theory, which suggests that malfunction of the magnocellular system in the brain is responsible for the behavioral deficits. We sought to test the basis of this theory by directly measuring the lateral geniculate nucleus (LGN), the only location in the brain where the magnocellular and parvocellular streams are spatially disjoint. Using high-resolution proton-density weighted MRI scans, we precisely measured the anatomical boundaries of the LGN in 13 subjects with dyslexia (five female) and 13 controls (three female), all 22–26 years old. The left LGN was significantly smaller in volume in subjects with dyslexia and also differed in shape; no differences were observed in the right LGN. The functional significance of this asymmetry is unknown, but these results are consistent with the magnocellular theory and support theories of dyslexia that involve differences in the early visual system. PMID:26082892

Left neglect dyslexia: Perseveration and reading error types.

PubMed

Ronchi, Roberta; Algeri, Lorella; Chiapella, Laura; Gallucci, Marcello; Spada, Maria Simonetta; Vallar, Giuseppe

2016-08-01

Right-brain-damaged patients may show a reading disorder termed neglect dyslexia. Patients with left neglect dyslexia omit letters on the left-hand-side (the beginning, when reading left-to-right) part of the letter string, substitute them with other letters, and add letters to the left of the string. The aim of this study was to investigate the pattern of association, if any, between error types in patients with left neglect dyslexia and recurrent perseveration (a productive visuo-motor deficit characterized by addition of marks) in target cancellation. Specifically, we aimed at assessing whether different productive symptoms (relative to the reading and the visuo-motor domains) could be associated in patients with left spatial neglect. Fifty-four right-brain-damaged patients took part in the study: 50 out of the 54 patients showed left spatial neglect, with 27 of them also exhibiting left neglect dyslexia. Neglect dyslexic patients who showed perseveration produced mainly substitution neglect errors in reading. Conversely, omissions were the prevailing reading error pattern in neglect dyslexic patients without perseveration. Addition reading errors were much infrequent. Different functional pathological mechanisms may underlie omission and substitution reading errors committed by right-brain-damaged patients with left neglect dyslexia. One such mechanism, involving the defective stopping of inappropriate responses, may contribute to both recurrent perseveration in target cancellation, and substitution errors in reading. Productive pathological phenomena, together with deficits of spatial attention to events taking place on the left-hand-side of space, shape the manifestations of neglect dyslexia, and, more generally, of spatial neglect. Copyright © 2016 Elsevier Ltd. All rights reserved.

Seminar: Developmental Dyslexia

PubMed Central

Peterson, Robin L.; Pennington, Bruce F.

2012-01-01

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

Atypical Balance between Occipital and Fronto-Parietal Activation for Visual Shape Extraction in Dyslexia

PubMed Central

Zhang, Ying; Whitfield-Gabrieli, Susan; Christodoulou, Joanna A.; Gabrieli, John D. E.

2013-01-01

Reading requires the extraction of letter shapes from a complex background of text, and an impairment in visual shape extraction would cause difficulty in reading. To investigate the neural mechanisms of visual shape extraction in dyslexia, we used functional magnetic resonance imaging (fMRI) to examine brain activation while adults with or without dyslexia responded to the change of an arrow’s direction in a complex, relative to a simple, visual background. In comparison to adults with typical reading ability, adults with dyslexia exhibited opposite patterns of atypical activation: decreased activation in occipital visual areas associated with visual perception, and increased activation in frontal and parietal regions associated with visual attention. These findings indicate that dyslexia involves atypical brain organization for fundamental processes of visual shape extraction even when reading is not involved. Overengagement in higher-order association cortices, required to compensate for underengagment in lower-order visual cortices, may result in competition for top-down attentional resources helpful for fluent reading. PMID:23825653

On children's dyslexia with NIRS

NASA Astrophysics Data System (ADS)

Gan, Zhuo; Li, Chengjun; Gong, Hui; Luo, Qingming; Yao, Bin; Song, Ranran; Wu, Hanrong

2003-12-01

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.

Sex-specific gray matter volume differences in females with developmental dyslexia.

PubMed

Evans, Tanya M; Flowers, D Lynn; Napoliello, Eileen M; Eden, Guinevere F

2014-05-01

Developmental dyslexia, characterized by unexpected reading difficulty, is associated with anomalous brain anatomy and function. Previous structural neuroimaging studies have converged in reports of less gray matter volume (GMV) in dyslexics within left hemisphere regions known to subserve language. Due to the higher prevalence of dyslexia in males, these studies are heavily weighted towards males, raising the question whether studies of dyslexia in females only and using the same techniques, would generate the same findings. In a replication study of men, we obtained the same findings of less GMV in dyslexics in left middle/inferior temporal gyri and right postcentral/supramarginal gyri as reported in the literature. However, comparisons in women with and without dyslexia did not yield left hemisphere differences, and instead, we found less GMV in right precuneus and paracentral lobule/medial frontal gyrus. In boys, we found less GMV in left inferior parietal cortex (supramarginal/angular gyri), again consistent with previous work, while in girls differences were within right central sulcus, spanning adjacent gyri, and left primary visual cortex. Our investigation into anatomical variants in dyslexia replicates existing studies in males, but at the same time shows that dyslexia in females is not characterized by involvement of left hemisphere language regions but rather early sensory and motor cortices (i.e., motor and premotor cortex, primary visual cortex). Our findings suggest that models on the brain basis of dyslexia, primarily developed through the study of males, may not be appropriate for females and suggest a need for more sex-specific investigations into dyslexia.

Sex-specific Gray Matter Volume Differences in Females with Developmental Dyslexia

PubMed Central

Evans, Tanya M.; Flowers, D. Lynn; Napoliello, Eileen M.; Eden, Guinevere F.

2013-01-01

Developmental dyslexia, characterized by unexpected reading difficulty, is associated with anomalous brain anatomy and function. Previous structural neuroimaging studies have converged in reports of less gray matter volume (GMV) in dyslexics within left hemisphere regions known to subserve language. Due to the higher prevalence of dyslexia in males, these studies are heavily weighted towards males, raising the question whether studies of dyslexia in females only and using the same techniques, would generate the same findings. In a replication study of men we obtained the same findings of less GMV in dyslexics in left middle/inferior temporal gyri and right postcentral/supramarginal gyri as reported in the literature. However, comparisons in women with and without dyslexia did not yield left hemisphere differences and instead we found less GMV in right precuneus and paracentral lobule/medial frontal gyrus. In boys, we found less GMV in left inferior parietal cortex (supramarginal/angular gyri), again consistent with previous work, while in girls differences were within right central sulcus, spanning adjacent gyri, and left primary visual cortex. Our investigation into anatomical variants in dyslexia replicates existing studies in males, but at the same time shows that dyslexia in females is not characterized by involvement of left hemisphere language regions but rather early sensory and motor cortices (i.e. motor and premotor cortex, primary visual cortex). Our findings suggest that models on the brain basis of dyslexia, primarily developed through the study of males, may not be appropriate for females and suggest a need for more sex-specific investigations into dyslexia. PMID:23625146

I-N-D-E-P-E-N-D-E-N-T: Increasing Reading Independence for Students with Dyslexia

ERIC Educational Resources Information Center

Milner, Diane Hansen

2017-01-01

Due to their unique brain profile, children with dyslexia struggle with acquiring basic literacy skills. Even after basic reading skills have been learned students with dyslexia may still struggle greatly with generalizing their skills to new contexts. Researchers have found that 75 percent of children identified with reading problems in third…

[Clinical interest of fMRI and functional exploration methods of brain activity and interactivity: physical and neurophysiological considerations].

PubMed

de Marco, G; Menuel, C; Guillevin, R; Vallée, J-N; Lehmann, P; Fall, S; Quaglino, V; Bourdin, B; Devauchelle, B; Chiras, J

2008-07-01

After having provided a brief reminder of the principle of the blood oxygen level-dependent (BOLD) contrast effect, the physiological bases of brain activity and the concepts of functional integration and effective connectivity, we describe the most recent approaches, which permit to explore brain activity and putative networks of interconnected active areas in order to examine the normal brain physiology and its dysfunctions. We present various methods and studies of brain activity analysis clinically applicable, and we detail the concepts of functional and effective connectivity, which allow to study the cerebral plasticity which occurs at the child's during the maturation (e.g., dyslexia), at the adult during the ageing (e.g., Alzheimer disease), or still in schizophrenia or Parkinson disease. The study of specific circuits in networks has to allow defining in a more realistic way the dynamic of the central nervous system, which underlies various cerebral functions, both in physiological and pathological conditions. This connectivity approach should improve the diagnostic and facilitate the development of new therapeutic strategies.

Grey Matter Alterations Co-Localize with Functional Abnormalities in Developmental Dyslexia: An ALE Meta-Analysis

PubMed Central

Linkersdörfer, Janosch; Lonnemann, Jan; Lindberg, Sven; Hasselhorn, Marcus; Fiebach, Christian J.

2012-01-01

The neural correlates of developmental dyslexia have been investigated intensively over the last two decades and reliable evidence for a dysfunction of left-hemispheric reading systems in dyslexic readers has been found in functional neuroimaging studies. In addition, structural imaging studies using voxel-based morphometry (VBM) demonstrated grey matter reductions in dyslexics in several brain regions. To objectively assess the consistency of these findings, we performed activation likelihood estimation (ALE) meta-analysis on nine published VBM studies reporting 62 foci of grey matter reduction in dyslexic readers. We found six significant clusters of convergence in bilateral temporo-parietal and left occipito-temporal cortical regions and in the cerebellum bilaterally. To identify possible overlaps between structural and functional deviations in dyslexic readers, we conducted additional ALE meta-analyses of imaging studies reporting functional underactivations (125 foci from 24 studies) or overactivations (95 foci from 11 studies ) in dyslexics. Subsequent conjunction analyses revealed overlaps between the results of the VBM meta-analysis and the meta-analysis of functional underactivations in the fusiform and supramarginal gyri of the left hemisphere. An overlap between VBM results and the meta-analysis of functional overactivations was found in the left cerebellum. The results of our study provide evidence for consistent grey matter variations bilaterally in the dyslexic brain and substantial overlap of these structural variations with functional abnormalities in left hemispheric regions. PMID:22916214

Examining the Relationship between Home Literacy Environment and Neural Correlates of Phonological Processing in Beginning Readers with and without a Familial Risk for Dyslexia: An fMRI Study

ERIC Educational Resources Information Center

Powers, Sara J.; Wang, Yingying; Beach, Sara D.; Sideridis, Georgios D.; Gaab, Nadine

2016-01-01

Developmental dyslexia is a language-based learning disability characterized by persistent difficulty in learning to read. While an understanding of genetic contributions is emerging, the ways the environment affects brain functioning in children with developmental dyslexia are poorly understood. A relationship between the home literacy…

The double-deficit hypothesis: a comprehensive analysis of the evidence.

PubMed

Vukovic, Rose K; Siegel, Linda S

2006-01-01

The double-deficit hypothesis of developmental dyslexia proposes that deficits in phonological processing and naming speed represent independent sources of dysfunction in dyslexia. The present article is a review of the evidence for the double-deficit hypothesis, including a discussion of recent findings related to the hypothesis. Studies in this area have been characterized by variability in methodology--how dyslexia is defined and identified, and how dyslexia subtypes are classified. Such variability sets limitations on the extent to which conclusions may be drawn with respect to the double-deficit hypothesis. Furthermore, the literature is complicated by the persistent finding that measures of phonological processing and naming speed are significantly correlated, resulting in a statistical artifact that makes it difficult to disentangle the influence of naming speed from that of phonological processing. Longitudinal and intervention studies of the double-deficit hypothesis are needed to accumulate evidence that investigates a naming speed deficit that is independent of a phonological deficit for readers with dyslexia. The existing evidence does not support a persistent core deficit in naming speed for readers with dyslexia.

Beyond a Reading Disability: Comments on the Need to Examine the Full Spectrum of Abilities/Disabilities of the Atypical Dyslexic Brain

ERIC Educational Resources Information Center

Gilger, Jeffrey W.

2017-01-01

A panel of practioners and researchers convened to consider how to advance a broader understanding of the neurocognitive profile of people with dyslexia. While a great deal of research has been conducted on the reading process, the panel recognized that the "dyslexia brain" may be unique in other ways as well. In particular, the panel…

Neural signatures of phonological deficits in Chinese developmental dyslexia.

PubMed

Cao, Fan; Yan, Xin; Wang, Zhao; Liu, Yanni; Wang, Jin; Spray, Gregory J; Deng, Yuan

2017-02-01

There has been debate on whether phonological deficits explain reading difficulty in Chinese, since Chinese is a logographic language which does not employ grapheme-phoneme-correspondence rules and remote memorization seems to be the main method to acquire reading. In the current study, we present neuroimaging evidence that the phonological deficit is also a signature of Chinese dyslexia. Specifically, we found that Chinese children with dyslexia (DD) showed reduced brain activation in the left dorsal inferior frontal gyrus (dIFG) when compared to both age-matched controls (AC) and reading-matched controls (RC) during an auditory rhyming judgment task. This suggests that the phonological processing deficit in this region may be a signature of dyslexia in Chinese, rather than a difference due to task performance or reading ability, which was matched on DD and RC. At exactly the same region of the left dIFG, we found a positive correlation between brain activation and reading skill in DD, suggesting that the phonological deficit is associated with the severity of dyslexia. We also found increased brain activation in the right precentral gyrus in DD than both AC and RC, suggesting a compensation of reliance on articulation. Functional connectivity analyses revealed that DD had a weaker connection between the left superior temporal gyrus (STG) and fusiform gyrus (FG) than the two control groups, suggesting that the reduced connection between phonology and orthography is another neural signature of dyslexia. In contrast, DD showed greater connectivity between the left dIFG and the left inferior parietal lobule (IPL) than both control groups, suggesting a reduced segregation between the language network and default mode network in dyslexic children. We also found that connectivity between the left STG and the left dIFG was sensitive to task performance and/or reading skill rather than being dyslexic or not, because AC was greater than both RC and DD, while the connectivity between the left middle occipital gyrus (MOG) and left STG was sensitive to age, because both AC and DD were greater than RC. In summary, our study provides the very first neurological evidence of phonological deficits in Chinese developmental dyslexia and we successfully distinguished variations of brain activity/functional connectivity due to age, performance, and dyslexia by comparing AC, RC, and DD. Copyright © 2016 Elsevier Inc. All rights reserved.

Response to "The Many Faces of Dyslexia."

ERIC Educational Resources Information Center

Galaburda, Albert M.

1986-01-01

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)

Incidental learning of sound categories is impaired in developmental dyslexia.

PubMed

Gabay, Yafit; Holt, Lori L

2015-12-01

Developmental dyslexia is commonly thought to arise from specific phonological impairments. However, recent evidence is consistent with the possibility that phonological impairments arise as symptoms of an underlying dysfunction of procedural learning. The nature of the link between impaired procedural learning and phonological dysfunction is unresolved. Motivated by the observation that speech processing involves the acquisition of procedural category knowledge, the present study investigates the possibility that procedural learning impairment may affect phonological processing by interfering with the typical course of phonetic category learning. The present study tests this hypothesis while controlling for linguistic experience and possible speech-specific deficits by comparing auditory category learning across artificial, nonlinguistic sounds among dyslexic adults and matched controls in a specialized first-person shooter videogame that has been shown to engage procedural learning. Nonspeech auditory category learning was assessed online via within-game measures and also with a post-training task involving overt categorization of familiar and novel sound exemplars. Each measure reveals that dyslexic participants do not acquire procedural category knowledge as effectively as age- and cognitive-ability matched controls. This difference cannot be explained by differences in perceptual acuity for the sounds. Moreover, poor nonspeech category learning is associated with slower phonological processing. Whereas phonological processing impairments have been emphasized as the cause of dyslexia, the current results suggest that impaired auditory category learning, general in nature and not specific to speech signals, could contribute to phonological deficits in dyslexia with subsequent negative effects on language acquisition and reading. Implications for the neuro-cognitive mechanisms of developmental dyslexia are discussed. Copyright © 2015 Elsevier Ltd. All rights reserved.

Incidental Learning of Sound Categories is Impaired in Developmental Dyslexia

PubMed Central

Gabay, Yafit; Holt, Lori L.

2015-01-01

Developmental dyslexia is commonly thought to arise from specific phonological impairments. However, recent evidence is consistent with the possibility that phonological impairments arise as symptoms of an underlying dysfunction of procedural learning. The nature of the link between impaired procedural learning and phonological dysfunction is unresolved. Motivated by the observation that speech processing involves the acquisition of procedural category knowledge, the present study investigates the possibility that procedural learning impairment may affect phonological processing by interfering with the typical course of phonetic category learning. The present study tests this hypothesis while controlling for linguistic experience and possible speech-specific deficits by comparing auditory category learning across artificial, nonlinguistic sounds among dyslexic adults and matched controls in a specialized first-person shooter videogame that has been shown to engage procedural learning. Nonspeech auditory category learning was assessed online via within-game measures and also with a post-training task involving overt categorization of familiar and novel sound exemplars. Each measure reveals that dyslexic participants do not acquire procedural category knowledge as effectively as age- and cognitive-ability matched controls. This difference cannot be explained by differences in perceptual acuity for the sounds. Moreover, poor nonspeech category learning is associated with slower phonological processing. Whereas phonological processing impairments have been emphasized as the cause of dyslexia, the current results suggest that impaired auditory category learning, general in nature and not specific to speech signals, could contribute to phonological deficits in dyslexia with subsequent negative effects on language acquisition and reading. Implications for the neuro-cognitive mechanisms of developmental dyslexia are discussed. PMID:26409017

Probabilistic Category Learning in Developmental Dyslexia: Evidence from Feedback and Paired-Associate Weather Prediction Tasks

PubMed Central

Gabay, Yafit; Vakil, Eli; Schiff, Rachel; Holt, Lori L.

2015-01-01

Objective Developmental dyslexia is presumed to arise from specific phonological impairments. However, an emerging theoretical framework suggests that phonological impairments may be symptoms stemming from an underlying dysfunction of procedural learning. Method We tested procedural learning in adults with dyslexia (n=15) and matched-controls (n=15) using two versions of the Weather Prediction Task: Feedback (FB) and Paired-associate (PA). In the FB-based task, participants learned associations between cues and outcomes initially by guessing and subsequently through feedback indicating the correctness of response. In the PA-based learning task, participants viewed the cue and its associated outcome simultaneously without overt response or feedback. In both versions, participants trained across 150 trials. Learning was assessed in a subsequent test without presentation of the outcome, or corrective feedback. Results The Dyslexia group exhibited impaired learning compared with the Control group on both the FB and PA versions of the weather prediction task. Conclusions The results indicate that the ability to learn by feedback is not selectively impaired in dyslexia. Rather it seems that the probabilistic nature of the task, shared by the FB and PA versions of the weather prediction task, hampers learning in those with dyslexia. Results are discussed in light of procedural learning impairments among participants with dyslexia. PMID:25730732

Audiovisual speech integration in the superior temporal region is dysfunctional in dyslexia.

PubMed

Ye, Zheng; Rüsseler, Jascha; Gerth, Ivonne; Münte, Thomas F

2017-07-25

Dyslexia is an impairment of reading and spelling that affects both children and adults even after many years of schooling. Dyslexic readers have deficits in the integration of auditory and visual inputs but the neural mechanisms of the deficits are still unclear. This fMRI study examined the neural processing of auditorily presented German numbers 0-9 and videos of lip movements of a German native speaker voicing numbers 0-9 in unimodal (auditory or visual) and bimodal (always congruent) conditions in dyslexic readers and their matched fluent readers. We confirmed results of previous studies that the superior temporal gyrus/sulcus plays a critical role in audiovisual speech integration: fluent readers showed greater superior temporal activations for combined audiovisual stimuli than auditory-/visual-only stimuli. Importantly, such an enhancement effect was absent in dyslexic readers. Moreover, the auditory network (bilateral superior temporal regions plus medial PFC) was dynamically modulated during audiovisual integration in fluent, but not in dyslexic readers. These results suggest that superior temporal dysfunction may underly poor audiovisual speech integration in readers with dyslexia. Copyright © 2017 IBRO. Published by Elsevier Ltd. All rights reserved.

Reading, Dyslexia and the Brain

ERIC Educational Resources Information Center

Goswami, Usha

2008-01-01

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…

Machine learning and dyslexia: Classification of individual structural neuro-imaging scans of students with and without dyslexia.

PubMed

Tamboer, P; Vorst, H C M; Ghebreab, S; Scholte, H S

2016-01-01

Meta-analytic studies suggest that dyslexia is characterized by subtle and spatially distributed variations in brain anatomy, although many variations failed to be significant after corrections of multiple comparisons. To circumvent issues of significance which are characteristic for conventional analysis techniques, and to provide predictive value, we applied a machine learning technique--support vector machine--to differentiate between subjects with and without dyslexia. In a sample of 22 students with dyslexia (20 women) and 27 students without dyslexia (25 women) (18-21 years), a classification performance of 80% (p < 0.001; d-prime = 1.67) was achieved on the basis of differences in gray matter (sensitivity 82%, specificity 78%). The voxels that were most reliable for classification were found in the left occipital fusiform gyrus (LOFG), in the right occipital fusiform gyrus (ROFG), and in the left inferior parietal lobule (LIPL). Additionally, we found that classification certainty (e.g. the percentage of times a subject was correctly classified) correlated with severity of dyslexia (r = 0.47). Furthermore, various significant correlations were found between the three anatomical regions and behavioural measures of spelling, phonology and whole-word-reading. No correlations were found with behavioural measures of short-term memory and visual/attentional confusion. These data indicate that the LOFG, ROFG and the LIPL are neuro-endophenotype and potentially biomarkers for types of dyslexia related to reading, spelling and phonology. In a second and independent sample of 876 young adults of a general population, the trained classifier of the first sample was tested, resulting in a classification performance of 59% (p = 0.07; d-prime = 0.65). This decline in classification performance resulted from a large percentage of false alarms. This study provided support for the use of machine learning in anatomical brain imaging.

Cognitive subtypes of dyslexia are characterized by distinct patterns of grey matter volume.

PubMed

Jednoróg, Katarzyna; Gawron, Natalia; Marchewka, Artur; Heim, Stefan; Grabowska, Anna

2014-09-01

The variety of different causal theories together with inconsistencies about the anatomical brain markers emphasize the heterogeneity of developmental dyslexia. Attempts were made to test on a behavioral level the existence of subtypes of dyslexia showing distinguishable cognitive deficits. Importantly, no research was directly devoted to the investigation of structural brain correlates of these subtypes. Here, for the first time, we applied voxel-based morphometry (VBM) to study grey matter volume (GMV) differences in a relatively large sample (n = 46) of dyslexic children split into three subtypes based on the cognitive deficits: phonological, rapid naming, magnocellular/dorsal, and auditory attention shifting. VBM revealed GMV clusters specific for each studied group including areas of left inferior frontal gyrus, cerebellum, right putamen, and bilateral parietal cortex. In addition, using discriminant analysis on these clusters 79% of cross-validated cases were correctly re-classified into four groups (controls vs. three subtypes). Current results indicate that dyslexia may result from distinct cognitive impairments characterized by distinguishable anatomical markers.

Similar alterations in brain function for phonological and semantic processing to visual characters in Chinese dyslexia.

PubMed

Liu, Li; Wang, Wenjing; You, Wenping; Li, Yi; Awati, Neha; Zhao, Xu; Booth, James R; Peng, Danling

2012-07-01

Dyslexia in alphabetic languages has been extensively investigated and suggests a central deficit in orthography to phonology mapping in the left hemisphere. Compared to dyslexia in alphabetic languages, the central deficit for Chinese dyslexia is still unclear. Because of the logographic nature of Chinese characters, some have suggested that Chinese dyslexia should have larger deficits in the semantic system. To investigate this, Chinese children with reading disability (RD) were compared to typically developing (TD) children using functional magnetic resonance imaging (fMRI) on a rhyming judgment task and on a semantic association judgment task. RD children showed less activation for both tasks in right visual (BA18, 19) and left occipito-temporal cortex (BA 37), suggesting a deficit in visuo-orthographic processing. RD children also showed less activation for both tasks in left inferior frontal gyrus (BA44), which additionally showed significant correlations with activation of bilateral visuo-orthographic regions in the RD group, suggesting that the abnormalities in frontal cortex and in posterior visuo-orthographic regions may reflect a deficit in the connection between brain regions. Analyses failed to reveal larger differences between groups for the semantic compared to the rhyming task, suggesting that Chinese dyslexia is similarly impaired in the access to phonology and to semantics from the visual orthography. Copyright © 2012 Elsevier Ltd. All rights reserved.

Short-term memory for order but not for item information is impaired in developmental dyslexia.

PubMed

Hachmann, Wibke M; Bogaerts, Louisa; Szmalec, Arnaud; Woumans, Evy; Duyck, Wouter; Job, Remo

2014-07-01

Recent findings suggest that people with dyslexia experience difficulties with the learning of serial order information during the transition from short- to long-term memory (Szmalec et al. Journal of Experimental Psychology: Learning, Memory, & Cognition 37(5): 1270-1279, 2011). At the same time, models of short-term memory increasingly incorporate a distinction of order and item processing (Majerus et al. Cognition 107: 395-419, 2008). The current study is aimed to investigate whether serial order processing deficiencies in dyslexia can be traced back to a selective impairment of short-term memory for serial order and whether this impairment also affects processing beyond the verbal domain. A sample of 26 adults with dyslexia and a group of age and IQ-matched controls participated in a 2 × 2 × 2 experiment in which we assessed short-term recognition performance for order and item information, using both verbal and nonverbal material. Our findings indicate that, irrespective of the type of material, participants with dyslexia recalled the individual items with the same accuracy as the matched control group, whereas the ability to recognize the serial order in which those items were presented appeared to be affected in the dyslexia group. We conclude that dyslexia is characterized by a selective impairment of short-term memory for serial order, but not for item information, and discuss the integration of these findings into current theoretical views on dyslexia and its associated dysfunctions.

Relationships between Eye Movements during Sentence Reading Comprehension, Word Spelling and Reading, and DTI and fmri Connectivity In Students with and without Dysgraphia or Dyslexia

PubMed Central

Yagle, Kevin; Richards, Todd; Askren, Katie; Mestre, Zoe; Beers, Scott; Abbott, Robert; Nagy, William; Boord, Peter; Berninger, Virginia

2017-01-01

While eye movements were recorded and brains scanned, 29 children with and without specific learning disabilities (SLDs) decided if sentences they read (half with only correctly spelled words and half with homonym foils) were meaningful. Significant main effects were found for diagnostic groups (non-SLD control, dysgraphia control, and dyslexia) in total fixation (dwell) time, total number of fixations, and total regressions in during saccades; the dyslexia group had longer and more fixations and made more regressions in during saccades than either control group. The dyslexia group also differed from both control groups in (a) fractional anisotropy in left optic radiation and (b) silent word reading fluency on a task in which surrounding letters can be distracting, consistent with Rayner's selective attention dyslexia model. Different profiles for non-SLD control, dysgraphia, and dyslexia groups were identified in correlations between total fixation time, total number of fixations, regressions in during saccades, magnitude of gray matter connectivity during the fMRI sentence reading comprehension from left occipital temporal cortex seed with right BA44 and from left inferior frontal gyrus with right inferior frontoccipital fasciculus, and normed word-specific spelling and silent word reading fluency measures. The dysgraphia group was more likely than the non-SLD control or dyslexia groups to show negative correlations between eye movement outcomes and sentences containing incorrect homonym foils. Findings are discussed in reference to a systems approach in future sentence reading comprehension research that integrates eye movement, brain, and literacy measures. PMID:28936361

Relationships between Eye Movements during Sentence Reading Comprehension, Word Spelling and Reading, and DTI and fmri Connectivity In Students with and without Dysgraphia or Dyslexia.

PubMed

Yagle, Kevin; Richards, Todd; Askren, Katie; Mestre, Zoe; Beers, Scott; Abbott, Robert; Nagy, William; Boord, Peter; Berninger, Virginia

2017-01-01

While eye movements were recorded and brains scanned, 29 children with and without specific learning disabilities (SLDs) decided if sentences they read (half with only correctly spelled words and half with homonym foils) were meaningful. Significant main effects were found for diagnostic groups (non-SLD control, dysgraphia control, and dyslexia) in total fixation (dwell) time, total number of fixations, and total regressions in during saccades; the dyslexia group had longer and more fixations and made more regressions in during saccades than either control group. The dyslexia group also differed from both control groups in (a) fractional anisotropy in left optic radiation and (b) silent word reading fluency on a task in which surrounding letters can be distracting, consistent with Rayner's selective attention dyslexia model. Different profiles for non-SLD control, dysgraphia, and dyslexia groups were identified in correlations between total fixation time, total number of fixations, regressions in during saccades, magnitude of gray matter connectivity during the fMRI sentence reading comprehension from left occipital temporal cortex seed with right BA44 and from left inferior frontal gyrus with right inferior frontoccipital fasciculus, and normed word-specific spelling and silent word reading fluency measures. The dysgraphia group was more likely than the non-SLD control or dyslexia groups to show negative correlations between eye movement outcomes and sentences containing incorrect homonym foils. Findings are discussed in reference to a systems approach in future sentence reading comprehension research that integrates eye movement, brain, and literacy measures.

Functional Neuroanatomy of Impaired Reading in Dyslexia

ERIC Educational Resources Information Center

Salmelin, Riitta; Helenius, Paivi

2004-01-01

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)…

Shared vs. specific brain activation changes in dyslexia after training of phonology, attention, or reading.

PubMed

Heim, Stefan; Pape-Neumann, Julia; van Ermingen-Marbach, Muna; Brinkhaus, Moti; Grande, Marion

2015-07-01

Whereas the neurobiological basis of developmental dyslexia has received substantial attention, only little is known about the processes in the brain during remediation. This holds in particular in light of recent findings on cognitive subtypes of dyslexia which suggest interactions between individual profiles, training methods, and also the task in the scanner. Therefore, we trained three groups of German dyslexic primary school children in the domains of phonology, attention, or visual word recognition. We compared neurofunctional changes after 4 weeks of training in these groups to those in untrained normal readers in a reading task and in a task of visual attention. The overall reading improvement in the dyslexic children was comparable over groups. It was accompanied by substantial increase of the activation level in the visual word form area (VWFA) during a reading task inside the scanner. Moreover, there were activation increases that were unique for each training group in the reading task. In contrast, when children performed the visual attention task, shared training effects were found in the left inferior frontal sulcus and gyrus, which varied in amplitude between the groups. Overall, the data reveal that different remediation programmes matched to individual profiles of dyslexia may improve reading ability and commonly affect the VWFA in dyslexia as a shared part of otherwise distinct networks.

Disrupted white matter connectivity underlying developmental dyslexia: A machine learning approach.

PubMed

Cui, Zaixu; Xia, Zhichao; Su, Mengmeng; Shu, Hua; Gong, Gaolang

2016-04-01

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. © 2016 Wiley Periodicals, Inc.

Imaging-Genetics in Dyslexia: Connecting risk genetic variants to brain neuroimaging and ultimately to reading impairments

PubMed Central

Eicher, John D.; Gruen, Jeffrey R.

2013-01-01

Dyslexia is a common pediatric disorder that affects 5-17% of schoolchildren in the United States. It is marked by unexpected difficulties in fluent reading despite adequate intelligence, opportunity, and instruction. Classically, neuropsychologists have studied dyslexia using a variety of neurocognitive batteries to gain insight into the specific deficits and impairments in affected children. Since dyslexia is a complex genetic trait with high heritability, analyses conditioned on performance on these neurocognitive batteries have been used to try to identify associated genes. This has led to some successes in identifying contributing genes, although much of the heritability remains unexplained. Additionally, the lack of relevant human brain tissue for analysis and the challenges of modeling a uniquely human trait in animals are barriers to advancing our knowledge of the underlying pathophysiology. In vivo imaging technologies, however, present new opportunities to examine dyslexia and reading skills in a clearly relevant context in human subjects. Recent investigations have started to integrate these imaging data with genetic data in attempts to gain a more complete and complex understanding of reading processes. In addition to bridging the gap from genetic risk variant to a discernible neuroimaging phenotype and ultimately to the clinical impairments in reading performance, the use of neuroimaging phenotypes will reveal novel risk genes and variants. In this article, we briefly discuss the genetic and imaging investigations and take an in-depth look at the recent imaging-genetics investigations of dyslexia. PMID:23916419

Hemispheric asymmetries in the orientation and location of the lateral geniculate nucleus in dyslexia.

PubMed

Giraldo-Chica, Mónica; Schneider, Keith A

2018-05-01

Human brain asymmetry reflects normal specialization of functional roles and may derive from evolutionary, hereditary, developmental, experiential, and pathological factors (Toga & Thompson, 2003). Geschwind and Galaburda (1985) suggested that processing difficulties in dyslexia are due to structural differences between hemispheres. Because of its potential significance to the controversial magnocellular theory of dyslexia, we investigated hemispheric differences in the human lateral geniculate nucleus (LGN), the primary visual relay and control nucleus in the thalamus, in subjects with dyslexia compared to normal readers. We acquired and averaged multiple high-resolution proton density (PD) weighted structural magnetic resonance imaging (MRI) volumes to measure in detail the anatomical boundaries of the LGN in each hemisphere. We observed hemispheric asymmetries in the orientation of the nucleus in subjects with dyslexia that were absent in controls. We also found differences in the location of the LGN between hemispheres in controls but not in subjects with dyslexia. Neither the precise anatomical differences in the LGN nor their functional consequences are known, nor is it clear whether the differences might be causes or effects of dyslexia. Copyright © 2018 John Wiley & Sons, Ltd.

Examining the relationship between home literacy environment and neural correlates of phonological processing in beginning readers with and without a familial risk for dyslexia: an fMRI study

PubMed Central

Powers, Sara J.; Wang, Yingying; Beach, Sara D.; Sideridis, Georgios D.; Gaab, Nadine

2016-01-01

Developmental dyslexia is a language-based learning disability characterized by persistent difficulty in learning to read. While an understanding of genetic contributions is emerging, the ways the environment affects brain functioning in children with developmental dyslexia are poorly understood. A relationship between the home literacy environment (HLE) and neural correlates of reading has been identified in typically developing children, yet it remains unclear whether similar effects are observable in children with a genetic predisposition for dyslexia. Understanding environmental contributions is important given that we do not understand why some genetically at-risk children do not develop dyslexia. Here we investigate for the first time the relationship between HLE and the neural correlates of phonological processing in beginning readers with (FHD+, n=29) and without (FHD−, n=21) a family history of developmental dyslexia. We controlled for socio-economic status to isolate the neurobiological mechanism by which HLE affects reading development. Group differences revealed stronger correlation of HLE with brain activation in the left inferior/middle frontal and right fusiform gyri in FHD− compared to FHD+ children, suggesting greater impact of HLE on manipulation of phonological codes and recruitment of orthographic representations in typically developing children. In contrast, activation in the right precentral gyrus showed a significantly stronger correlation with HLE in FHD+ compared to FHD− children, suggesting emerging compensatory networks in genetically at-risk children. Overall, our results suggest that genetic predisposition for dyslexia alters contributions of HLE to early reading skills before formal reading instruction, which has important implications for educational practice and intervention models. PMID:27550556

Examining the relationship between home literacy environment and neural correlates of phonological processing in beginning readers with and without a familial risk for dyslexia: an fMRI study.

PubMed

Powers, Sara J; Wang, Yingying; Beach, Sara D; Sideridis, Georgios D; Gaab, Nadine

2016-10-01

Developmental dyslexia is a language-based learning disability characterized by persistent difficulty in learning to read. While an understanding of genetic contributions is emerging, the ways the environment affects brain functioning in children with developmental dyslexia are poorly understood. A relationship between the home literacy environment (HLE) and neural correlates of reading has been identified in typically developing children, yet it remains unclear whether similar effects are observable in children with a genetic predisposition for dyslexia. Understanding environmental contributions is important given that we do not understand why some genetically at-risk children do not develop dyslexia. Here, we investigate for the first time the relationship between HLE and the neural correlates of phonological processing in beginning readers with (FHD+, n = 29) and without (FHD-, n = 21) a family history of developmental dyslexia. We further controlled for socioeconomic status to isolate the neurobiological mechanism by which HLE affects reading development. Group differences revealed stronger correlation of HLE with brain activation in the left inferior/middle frontal and right fusiform gyri in FHD- compared to FHD+ children, suggesting greater impact of HLE on manipulation of phonological codes and recruitment of orthographic representations in typically developing children. In contrast, activation in the right precentral gyrus showed a significantly stronger correlation with HLE in FHD+ compared to FHD- children, suggesting emerging compensatory networks in genetically at-risk children. Overall, our results suggest that genetic predisposition for dyslexia alters contributions of HLE to early reading skills before formal reading instruction, which has important implications for educational practice and intervention models.

[Neurobiology and neurogenetics of dyslexia].

PubMed

Benítez-Burraco, A

2010-01-01

Dyslexia is a learning disability in which reading (but not any other) impairment is the most prominent symptom. There seems to be a high comorbidity among dyslexia and other learning disabilities, such as SLI, SSD or ADHD. The nulear deficit in dyslexia appears to correspond to an impairment in phonological processing. Structural and functional studies in dyslexic readers converge to indicate the presence of malformations in the brain areas corresponding to the reading systems, but also a failure of these systems to function properly during reading. Genes linked (or associated) to dyslexia have been shown to be involved in neuronal migration and axon guidance during the formation of the cortex. In the developing cerebral neocortex of rats, local loss of function of most of these genes not only results in abnormal neuronal migration and neocortical and hippocampal malformations, but also in deficits related to auditory processing and learning. While the structural malformations resemble neuronal migration abnormalities observed in the brains of individuals with developmental dyslexia, processing/learning deficits also resemble deficits described in individuals affected by the disease. On the whole, dyslexia seems to be on a continuum with typical reading at different biological levels (genetic, biochemical, physiological, cognitive). Furthermore, certain elements belonging to some of these levels (mainly -some of the- genes linked or associated to the disease, but also -some of the- neuronal structures whose development is regulated by these genes) would simultaneously belong to those of other cognitive abilities, which give rise to diseases of a different nature (i.e. non- dyslexic impairments) when they are impaired. Copyright © 2009 Sociedad Española de Neurología. Published by Elsevier Espana. All rights reserved.

It's about time: revisiting temporal processing deficits in dyslexia.

PubMed

Casini, Laurence; Pech-Georgel, Catherine; Ziegler, Johannes C

2018-03-01

Temporal processing in French children with dyslexia was evaluated in three tasks: a word identification task requiring implicit temporal processing, and two explicit temporal bisection tasks, one in the auditory and one in the visual modality. Normally developing children matched on chronological age and reading level served as a control group. Children with dyslexia exhibited robust deficits in temporal tasks whether they were explicit or implicit and whether they involved the auditory or the visual modality. First, they presented larger perceptual variability when performing temporal tasks, whereas they showed no such difficulties when performing the same task on a non-temporal dimension (intensity). This dissociation suggests that their difficulties were specific to temporal processing and could not be attributed to lapses of attention, reduced alertness, faulty anchoring, or overall noisy processing. In the framework of cognitive models of time perception, these data point to a dysfunction of the 'internal clock' of dyslexic children. These results are broadly compatible with the recent temporal sampling theory of dyslexia. © 2017 John Wiley & Sons Ltd.

Abnormal Visual Motion Processing is not a Cause of Dyslexia

PubMed Central

Olulade, Olumide A.; Napoliello, Eileen M.; Eden, Guinevere F.

2013-01-01

SUMMARY Developmental dyslexia is a reading disorder, yet deficits also manifest in the magnocellular-dominated dorsal visual system. Uncertainty about whether visual deficits are causal or consequential to reading disability encumbers accurate identification and appropriate treatment of this common learning disability. Using fMRI, we demonstrate in typical readers a relationship between reading ability and activity in area V5/MT during visual motion processing and, as expected, also found lower V5/MT activity for dyslexic children compared to age-matched controls. However, when dyslexics were matched to younger controls on reading ability, no differences emerged, suggesting that weakness in V5/MT may not be causal to dyslexia. To further test for causality, dyslexics underwent a phonological-based reading intervention. Surprisingly, V5/MT activity increased along with intervention-driven reading gains, demonstrating that activity here is mobilized through reading. Our results provide strong evidence that visual magnocellular dysfunction is not causal to dyslexia, but may instead be consequential to impoverished reading. PMID:23746630

Machine learning and dyslexia: Classification of individual structural neuro-imaging scans of students with and without dyslexia

PubMed Central

Tamboer, P.; Vorst, H.C.M.; Ghebreab, S.; Scholte, H.S.

2016-01-01

Meta-analytic studies suggest that dyslexia is characterized by subtle and spatially distributed variations in brain anatomy, although many variations failed to be significant after corrections of multiple comparisons. To circumvent issues of significance which are characteristic for conventional analysis techniques, and to provide predictive value, we applied a machine learning technique – support vector machine – to differentiate between subjects with and without dyslexia. In a sample of 22 students with dyslexia (20 women) and 27 students without dyslexia (25 women) (18–21 years), a classification performance of 80% (p < 0.001; d-prime = 1.67) was achieved on the basis of differences in gray matter (sensitivity 82%, specificity 78%). The voxels that were most reliable for classification were found in the left occipital fusiform gyrus (LOFG), in the right occipital fusiform gyrus (ROFG), and in the left inferior parietal lobule (LIPL). Additionally, we found that classification certainty (e.g. the percentage of times a subject was correctly classified) correlated with severity of dyslexia (r = 0.47). Furthermore, various significant correlations were found between the three anatomical regions and behavioural measures of spelling, phonology and whole-word-reading. No correlations were found with behavioural measures of short-term memory and visual/attentional confusion. These data indicate that the LOFG, ROFG and the LIPL are neuro-endophenotype and potentially biomarkers for types of dyslexia related to reading, spelling and phonology. In a second and independent sample of 876 young adults of a general population, the trained classifier of the first sample was tested, resulting in a classification performance of 59% (p = 0.07; d-prime = 0.65). This decline in classification performance resulted from a large percentage of false alarms. This study provided support for the use of machine learning in anatomical brain imaging. PMID:27114899

Differential Diagnosis of Dysgraphia, Dyslexia, and OWL LD: Behavioral and Neuroimaging Evidence

PubMed Central

Berninger, Virginia W.; Richards, Todd; Abbott, Robert D.

2015-01-01

In Study 1, children in grades 4 to 9 (N= 88, 29 females and 59 males) with persisting reading and/or writing disabilities, despite considerable prior specialized instruction in and out of school, were given an evidence-based comprehensive assessment battery at the university while parents completed questionnaires regarding past and current history of language learning and other difficulties. Profiles (patterns) of normed measures for different levels of oral and written language used to categorize participants into diagnostic groups for dysgraphia (impaired subword handwriting) (n=26), dyslexia (impaired word spelling and reading) (n=38), or oral and written language learning disability OWL LD (impaired oral and written syntax comprehension and expression) (n=13) or control oral and written language learners (OWLs) without SLDs (n=11) were consistent withreported history. Impairments in working memory components supporting language learning were also examined. In Study 2, right handed children from Study 1 who did not wear braces (controls, n=9, dysgraphia, n= 14; dyslexia, n=17, OWL LD, n=5) completed an fMRI functional connectivity brain imaging study in which they performed a word-specific spelling judgment task, which is related to both word reading and spelling, and may be impaired in dysgraphia, dyslexia, and OWL LD for different reasons. fMRI functional connectivity from 4 seed points in brain locations involved in written word processing to other brain regions also differentiated dysgraphia, dyslexia, and OWL LD; both specific regions to which connected and overall number of functional connections differed. Thus, results provide converging neurological and behavioral evidence, for dysgraphia, dyslexia, and OWL LD being different, diagnosable specific learning disabilities (SLDs) for persisting written language problems during middle childhood and early adolescence. Translation of the research findings into practice at policy and administrative levels and at local school levels is discussed. PMID:26336330

Cognitive levels of performance account for hemispheric lateralisation effects in dyslexic and normally reading children.

PubMed

Heim, Stefan; Grande, Marion; Meffert, Elisabeth; Eickhoff, Simon B; Schreiber, Helen; Kukolja, Juraj; Shah, Nadim Jon; Huber, Walter; Amunts, Katrin

2010-12-01

Recent theories of developmental dyslexia explain reading deficits in terms of deficient phonological awareness, attention, visual and auditory processing, or automaticity. Since dyslexia has a neurobiological basis, the question arises how the reader's proficiency in these cognitive variables affects the brain regions involved in visual word recognition. This question was addressed in two fMRI experiments with 19 normally reading children (Experiment 1) and 19 children with dyslexia (Experiment 2). First, reading-specific brain activation was assessed by contrasting the BOLD signal for reading aloud words vs. overtly naming pictures of real objects. Next, ANCOVAs with brain activation during reading the individuals' scores for all five cognitive variables assessed outside the scanner as covariates were performed. Whereas the normal readers' brain activation during reading showed co-variation effects predominantly in the right hemisphere, the reverse pattern was observed for the dyslexics. In particular, middle frontal gyrus, inferior parietal cortex, and precuneus showed contralateral effects for controls as compared to dyslexics. In line with earlier findings in the literature, these data hint at a global change in hemispheric asymmetry during cognitive processing in dyslexic readers, which, in turn, might affect reading proficiency. Copyright © 2010 Elsevier Inc. All rights reserved.

Advances in Dyslexia Genetics-New Insights Into the Role of Brain Asymmetries.

PubMed

Paracchini, S; Diaz, R; Stein, J

2016-01-01

Dyslexia is a common condition affecting up to 10% school-aged children. There is strong evidence that genetics plays an important role in dyslexia and is expected to be complex in nature. Few specific susceptibility factors have been identified so far, but their functional characterization has provided novel insights into the biology of dyslexia. In particular, they point to an unexpected role of candidate genes for dyslexia in the biology of cilia, cellular organelles required in many processes including the establishment of left-right asymmetries early in development. This observation has brought back into the spotlight the old idea of a link between dyslexia and handedness. Yet much of the genetics contributing to dyslexia remains unexplained. The lack of biological markers, clear diagnostic criteria, and homogeneous assessment strategies are just some of the factors preventing the collection of the cohorts powered enough for large-scale genetic studies. While the technology and methods to generate and handle large-scale data have reached unprecedented potential, the main challenge remains in establishing universal guidelines to collect suitable phenotype information across independent studies. These difficulties reflect the complex nature of dyslexia which is highly heterogeneous and often co-occurs with other neurodevelopmental disorders. Copyright © 2016 Elsevier Inc. All rights reserved.

Normal radial migration and lamination are maintained in dyslexia-susceptibility candidate gene homolog Kiaa0319 knockout mice.

PubMed

Martinez-Garay, Isabel; Guidi, Luiz G; Holloway, Zoe G; Bailey, Melissa A G; Lyngholm, Daniel; Schneider, Tomasz; Donnison, Timothy; Butt, Simon J B; Monaco, Anthony P; Molnár, Zoltán; Velayos-Baeza, Antonio

2017-04-01

Developmental dyslexia is a common disorder with a strong genetic component, but the underlying molecular mechanisms are still unknown. Several candidate dyslexia-susceptibility genes, including KIAA0319, DYX1C1, and DCDC2, have been identified in humans. RNA interference experiments targeting these genes in rat embryos have shown impairments in neuronal migration, suggesting that defects in radial cortical migration could be involved in the disease mechanism of dyslexia. Here we present the first characterisation of a Kiaa0319 knockout mouse line. Animals lacking KIAA0319 protein do not show anatomical abnormalities in any of the layered structures of the brain. Neurogenesis and radial migration of cortical projection neurons are not altered, and the intrinsic electrophysiological properties of Kiaa0319-deficient neurons do not differ from those of wild-type neurons. Kiaa0319 overexpression in cortex delays radial migration, but does not affect final neuronal position. However, knockout animals show subtle differences suggesting possible alterations in anxiety-related behaviour and in sensorimotor gating. Our results do not reveal a migration disorder in the mouse model, adding to the body of evidence available for Dcdc2 and Dyx1c1 that, unlike in the rat in utero knockdown models, the dyslexia-susceptibility candidate mouse homolog genes do not play an evident role in neuronal migration. However, KIAA0319 protein expression seems to be restricted to the brain, not only in early developmental stages but also in adult mice, indicative of a role of this protein in brain function. The constitutive and conditional knockout lines reported here will be useful tools for further functional analyses of Kiaa0319.

Altered brain activity for phonological manipulation in dyslexic Japanese children.

PubMed

Kita, Yosuke; Yamamoto, Hisako; Oba, Kentaro; Terasawa, Yuri; Moriguchi, Yoshiya; Uchiyama, Hitoshi; Seki, Ayumi; Koeda, Tatsuya; Inagaki, Masumi

2013-12-01

Because of unique linguistic characteristics, the prevalence rate of developmental dyslexia is relatively low in the Japanese language. Paradoxically, Japanese children have serious difficulty analysing phonological processes when they have dyslexia. Neurobiological deficits in Japanese dyslexia remain unclear and need to be identified, and may lead to better understanding of the commonality and diversity in the disorder among different linguistic systems. The present study investigated brain activity that underlies deficits in phonological awareness in Japanese dyslexic children using functional magnetic resonance imaging. We developed and conducted a phonological manipulation task to extract phonological processing skills and to minimize the influence of auditory working memory on healthy adults, typically developing children, and dyslexic children. Current experiments revealed that several brain regions participated in manipulating the phonological information including left inferior and middle frontal gyrus, left superior temporal gyrus, and bilateral basal ganglia. Moreover, dyslexic children showed altered activity in two brain regions. They showed hyperactivity in the basal ganglia compared with the two other groups, which reflects inefficient phonological processing. Hypoactivity in the left superior temporal gyrus was also found, suggesting difficulty in composing and processing phonological information. The altered brain activity shares similarity with those of dyslexic children in countries speaking alphabetical languages, but disparity also occurs between these two populations. These are initial findings concerning the neurobiological impairments in dyslexic Japanese children.

Altered brain activity for phonological manipulation in dyslexic Japanese children

PubMed Central

Yamamoto, Hisako; Oba, Kentaro; Terasawa, Yuri; Moriguchi, Yoshiya; Uchiyama, Hitoshi; Seki, Ayumi; Koeda, Tatsuya; Inagaki, Masumi

2013-01-01

Because of unique linguistic characteristics, the prevalence rate of developmental dyslexia is relatively low in the Japanese language. Paradoxically, Japanese children have serious difficulty analysing phonological processes when they have dyslexia. Neurobiological deficits in Japanese dyslexia remain unclear and need to be identified, and may lead to better understanding of the commonality and diversity in the disorder among different linguistic systems. The present study investigated brain activity that underlies deficits in phonological awareness in Japanese dyslexic children using functional magnetic resonance imaging. We developed and conducted a phonological manipulation task to extract phonological processing skills and to minimize the influence of auditory working memory on healthy adults, typically developing children, and dyslexic children. Current experiments revealed that several brain regions participated in manipulating the phonological information including left inferior and middle frontal gyrus, left superior temporal gyrus, and bilateral basal ganglia. Moreover, dyslexic children showed altered activity in two brain regions. They showed hyperactivity in the basal ganglia compared with the two other groups, which reflects inefficient phonological processing. Hypoactivity in the left superior temporal gyrus was also found, suggesting difficulty in composing and processing phonological information. The altered brain activity shares similarity with those of dyslexic children in countries speaking alphabetical languages, but disparity also occurs between these two populations. These are initial findings concerning the neurobiological impairments in dyslexic Japanese children. PMID:24052613

Evidence for the Late MMN as a Neurophysiological Endophenotype for Dyslexia

PubMed Central

Neuhoff, Nina; Bruder, Jennifer; Bartling, Jürgen; Warnke, Andreas; Remschmidt, Helmut; Müller-Myhsok, Bertram; Schulte-Körne, Gerd

2012-01-01

Dyslexia affects 5–10% of school-aged children and is therefore one of the most common learning disorders. Research on auditory event related potentials (AERP), particularly the mismatch negativity (MMN) component, has revealed anomalies in individuals with dyslexia to speech stimuli. Furthermore, candidate genes for this disorder were found through molecular genetic studies. A current challenge for dyslexia research is to understand the interaction between molecular genetics and brain function, and to promote the identification of relevant endophenotypes for dyslexia. The present study examines MMN, a neurophysiological correlate of speech perception, and its potential as an endophenotype for dyslexia in three groups of children. The first group of children was clinically diagnosed with dyslexia, whereas the second group of children was comprised of their siblings who had average reading and spelling skills and were therefore “unaffected” despite having a genetic risk for dyslexia. The third group consisted of control children who were not related to the other groups and were also unaffected. In total, 225 children were included in the study. All children showed clear MMN activity to/da/−/ba/contrasts that could be separated into three distinct MMN components. Whilst the first two MMN components did not differentiate the groups, the late MMN component (300–700 ms) revealed significant group differences. The mean area of the late MMN was attenuated in both the dyslexic children and their unaffected siblings in comparison to the control children. This finding is indicative of analogous alterations of neurophysiological processes in children with dyslexia and those with a genetic risk for dyslexia, without a manifestation of the disorder. The present results therefore further suggest that the late MMN might be a potential endophenotype for dyslexia. PMID:22606227

Reading in dyslexia across literacy development: A longitudinal study of effective connectivity.

PubMed

Morken, Frøydis; Helland, Turid; Hugdahl, Kenneth; Specht, Karsten

2017-01-01

Dyslexia is a literacy disorder affecting the efficient acquisition of reading and writing skills. The disorder is neurobiological in origin. Due to its developmental nature, longitudinal studies of dyslexia are of essence. They are, however, relatively scarce. The present study took a longitudinal approach to cortical connectivity of brain imaging data in reading tasks in children with dyslexia and children with typical reading development. The participants were followed with repeated measurements through Pre-literacy (6 years old), Emergent Literacy (8 years old) and Literacy (12 years old) stages, using Dynamic Causal Modelling (DCM) when analysing functional magnetic resonance imaging (fMRI) data. Even though there are a few longitudinal studies on effective connectivity in typical reading, to our knowledge, no studies have previously investigated these issues in relation to dyslexia. We set up a model of a brain reading network involving five cortical regions (inferior frontal gyrus, precentral gyrus, superior temporal gyrus, inferior parietal lobule, and occipito-temporal cortex). Using DCM, connectivity measures were calculated for each connection in the model. These measures were further analysed using factorial ANOVA. The results showed that the difference between groups centred on connections going to and from the inferior frontal gyrus (two connections) and the occipito-temporal cortex (three connections). For all five connections, the typical group showed stable or decreasing connectivity measures. The dyslexia group, on the other hand, showed a marked up-regulation (occipito-temporal connections) or down-regulation (inferior frontal gyrus connections) from 6 years to 8 years, followed by normalization from 8 years to 12 years. We interpret this as a delay in the dyslexia group in developing into the Pre-literacy and Emergent literacy stages. This delay could possibly be detrimental to literacy development. By age 12, there was no statistically significant difference in connectivity between the groups, but differences in literacy skills were still present, and were in fact larger than when measured at younger ages. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

Out-of-synchrony speech entrainment in developmental dyslexia.

PubMed

Molinaro, Nicola; Lizarazu, Mikel; Lallier, Marie; Bourguignon, Mathieu; Carreiras, Manuel

2016-08-01

Developmental dyslexia is a reading disorder often characterized by reduced awareness of speech units. Whether the neural source of this phonological disorder in dyslexic readers results from the malfunctioning of the primary auditory system or damaged feedback communication between higher-order phonological regions (i.e., left inferior frontal regions) and the auditory cortex is still under dispute. Here we recorded magnetoencephalographic (MEG) signals from 20 dyslexic readers and 20 age-matched controls while they were listening to ∼10-s-long spoken sentences. Compared to controls, dyslexic readers had (1) an impaired neural entrainment to speech in the delta band (0.5-1 Hz); (2) a reduced delta synchronization in both the right auditory cortex and the left inferior frontal gyrus; and (3) an impaired feedforward functional coupling between neural oscillations in the right auditory cortex and the left inferior frontal regions. This shows that during speech listening, individuals with developmental dyslexia present reduced neural synchrony to low-frequency speech oscillations in primary auditory regions that hinders higher-order speech processing steps. The present findings, thus, strengthen proposals assuming that improper low-frequency acoustic entrainment affects speech sampling. This low speech-brain synchronization has the strong potential to cause severe consequences for both phonological and reading skills. Interestingly, the reduced speech-brain synchronization in dyslexic readers compared to normal readers (and its higher-order consequences across the speech processing network) appears preserved through the development from childhood to adulthood. Thus, the evaluation of speech-brain synchronization could possibly serve as a diagnostic tool for early detection of children at risk of dyslexia. Hum Brain Mapp 37:2767-2783, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

The DCDC2/intron 2 deletion and white matter disorganization: focus on developmental dyslexia.

PubMed

Marino, Cecilia; Scifo, Paola; Della Rosa, Pasquale A; Mascheretti, Sara; Facoetti, Andrea; Lorusso, Maria L; Giorda, Roberto; Consonni, Monica; Falini, Andrea; Molteni, Massimo; Gruen, Jeffrey R; Perani, Daniela

2014-08-01

The DCDC2 gene is involved in neuronal migration. Heterotopias have been found within the white matter of DCDC2-knockdown rats. A deletion in DCDC2/intron 2 (DCDC2d), which encompasses a regulatory region named 'regulatory element associated with dyslexia 1' (READ1), increases the risk for dyslexia. We hypothesized that DCDC2d can be associated to alterations of the white matter structure in general and in dyslexic brains. Based on a full-factorial analysis of covariance (ANCOVA) model, we investigated voxel-based diffusion tensor imaging (VB-DTI) data of four groups of subjects: dyslexia with/without DCDC2d, and normal readers with/without DCDC2d. We also tested DCDC2d effects upon correlation patterns between fractional anisotropy (FA) and reading scores. We found that FA was reduced in the left arcuate fasciculus and splenium of the corpus callosum in subjects with versus without DCDC2d, irrespective of dyslexia. Subjects with dyslexia and DCDC2d showed reduced FA, mainly in the left hemisphere and in the corpus callosum; their counterpart without DCDC2d showed similar FA alterations. Noteworthy, a conjunction analysis in impaired readers revealed common regions with lower FA mainly in the left hemisphere. When we compared subjects with dyslexia with versus without DCDC2d, we found lower FA in the inferior longitudinal fasciculus and genu of the corpus callosum, bilaterally. Normal readers with versus without DCDC2d had FA increases and decreases in both the right and left hemisphere. The major contribution of our study was to provide evidence relating genes, brain and behaviour. Overall, our findings support the hypothesis that DCDC2d is associated with altered FA. In normal readers, DCDC2-related anatomical patterns may mark some developmental cognitive vulnerability to learning disabilities. In subjects with dyslexia, DCDC2d accounted for both common - mainly located in the left hemisphere - and unique - a more severe and extended pattern - alterations of white matter fibre tracts. Copyright © 2014 Elsevier Ltd. All rights reserved.

Disruption of functional networks in dyslexia: A whole-brain, data-driven analysis of connectivity

PubMed Central

Finn, Emily S.; Shen, Xilin; Holahan, John M.; Scheinost, Dustin; Lacadie, Cheryl; Papademetris, Xenophon; Shaywitz, Sally E.; Shaywitz, Bennett A.; Constable, R. Todd

2013-01-01

Background Functional connectivity analyses of fMRI data are a powerful tool for characterizing brain networks and how they are disrupted in neural disorders. However, many such analyses examine only one or a small number of a priori seed regions. Studies that consider the whole brain frequently rely on anatomic atlases to define network nodes, which may result in mixing distinct activation timecourses within a single node. Here, we improve upon previous methods by using a data-driven brain parcellation to compare connectivity profiles of dyslexic (DYS) versus non-impaired (NI) readers in the first whole-brain functional connectivity analysis of dyslexia. Methods Whole-brain connectivity was assessed in children (n = 75; 43 NI, 32 DYS) and adult (n = 104; 64 NI, 40 DYS) readers. Results Compared to NI readers, DYS readers showed divergent connectivity within the visual pathway and between visual association areas and prefrontal attention areas; increased right-hemisphere connectivity; reduced connectivity in the visual word-form area (part of the left fusiform gyrus specialized for printed words); and persistent connectivity to anterior language regions around the inferior frontal gyrus. Conclusions Together, findings suggest that NI readers are better able to integrate visual information and modulate their attention to visual stimuli, allowing them to recognize words based on their visual properties, while DYS readers recruit altered reading circuits and rely on laborious phonology-based “sounding out” strategies into adulthood. These results deepen our understanding of the neural basis of dyslexia and highlight the importance of synchrony between diverse brain regions for successful reading. PMID:24124929

Developmental Dyslexia, Neurolinguistic Theory and Deviations in Brain Morphology.

ERIC Educational Resources Information Center

Hynd, George W.; And Others

1991-01-01

Reviews computer tomography and magnetic resonance imaging studies examining deviations in brain morphology. Discusses methodological and technical issues. Concludes that dyslexics show variations in specific brain regions. Suggests that neuroimaging procedures appear to provide direct evidence supporting the importance of deviations in normal…

Brain connectivity associated with cascading levels of language.

PubMed

Richards, Todd; Nagy, William; Abbott, Robert; Berninger, Virginia

2016-01-01

Typical oral and written language learners (controls) (5 girls, 4 boys) completed fMRI reading judgment tasks (sub-word grapheme-phoneme, word spelling, sentences with and without spelling foils, affixed words, sentences with and without affix foils, and multi-sentence). Analyses identified connectivity within and across adjacent levels (units) of language in reading: from subword to word to syntax in Set I and from word to syntax to multi-sentence in Set II). Typicals were compared to (a) students with dyslexia (6 girls, 10 boys) on the subword and word tasks in Set I related to levels of language impaired in dyslexia, and (b) students with oral and written language learning disability (OWL LD) (3 girls, 2 boys) on the morphology and syntax tasks in Set II, related to levels of language impaired in OWL LD. Results for typical language learners showed that adjacent levels of language in the reading brain share common and unique connectivity. The dyslexia group showed over-connectivity to a greater degree on the imaging tasks related to their levels of language impairments than the OWL LD group who showed under-connectivity to a greater degree than did the dyslexia group on the imaging tasks related to their levels of language impairment. Results for these students in grades 4 to 9 (ages 9 to 14) are discussed in reference to the contribution of patterns of connectivity across levels of language to understanding the nature of persisting dyslexia and dysgraphia despite early intervention.

Shared temporoparietal dysfunction in dyslexia and typical readers with discrepantly high IQ.

PubMed

Hancock, Roeland; Gabrieli, John D E; Hoeft, Fumiko

2016-12-01

It is currently believed that reading disability (RD) should be defined by reading level without regard to broader aptitude (IQ). There is debate, however, about how to classify individuals who read in the typical range but less well than would be expected by their higher IQ. We used functional magnetic resonance imaging (fMRI) in 49 children to examine whether those with typical, but discrepantly low reading ability relative to IQ, show dyslexia-like activation patterns during reading. Children who were typical readers with high-IQ discrepancy showed reduced activation in left temporoparietal neocortex relative to two control groups of typical readers without IQ discrepancy. This pattern was consistent and spatially overlapping with results in children with RD compared to typically reading children. The results suggest a shared neurological atypicality in regions associated with phonological processing between children with dyslexia and children with typical reading ability that is substantially below their IQ.

Visual Perception and Reading: New Clues to Patterns of Dysfunction Across Multiple Visual Channels in Developmental Dyslexia.

PubMed

Pina Rodrigues, Ana; Rebola, José; Jorge, Helena; Ribeiro, Maria José; Pereira, Marcelino; van Asselen, Marieke; Castelo-Branco, Miguel

2017-01-01

The specificity of visual channel impairment in dyslexia has been the subject of much controversy. The purpose of this study was to determine if a differential pattern of impairment can be verified between visual channels in children with developmental dyslexia, and in particular, if the pattern of deficits is more conspicuous in tasks where the magnocellular-dorsal system recruitment prevails. Additionally, we also aimed at investigating the association between visual perception thresholds and reading. In the present case-control study, we compared perception thresholds of 33 children diagnosed with developmental dyslexia and 34 controls in a speed discrimination task, an achromatic contrast sensitivity task, and a chromatic contrast sensitivity task. Moreover, we addressed the correlation between the different perception thresholds and reading performance, as assessed by means of a standardized reading test (accuracy and fluency). Group comparisons were performed by the Mann-Whitney U test, and Spearman's rho was used as a measure of correlation. Results showed that, when compared to controls, children with dyslexia were more impaired in the speed discrimination task, followed by the achromatic contrast sensitivity task, with no impairment in the chromatic contrast sensitivity task. These results are also consistent with the magnocellular theory since the impairment profile of children with dyslexia in the visual threshold tasks reflected the amount of magnocellular-dorsal stream involvement. Moreover, both speed and achromatic thresholds were significantly correlated with reading performance, in terms of accuracy and fluency. Notably, chromatic contrast sensitivity thresholds did not correlate with any of the reading measures. Our evidence stands in favor of a differential visual channel deficit in children with developmental dyslexia and contributes to the debate on the pathophysiology of reading impairments.

Physics, Dyslexia and Learning: A Collaboration for Disabled Students

NASA Astrophysics Data System (ADS)

Moskal, Barbara M.; Wright, Lyndsey; Taylor, P. C.

2014-03-01

Researchers have found that children with dyslexia reason differently with respect to language from those who do not have dyslexia. Dyslexic students' brains work differently than do students without dyslexia. Some researchers speculate that these differences provide dyslexic students with an advantage in science. The presentation will describe an outreach activity which developed and delivered instructional modules in physics to students in grades kindergarten through sixth. These modules were tested on thirty students who attended a summer camp designed for students who have been diagnosed with dyslexia. Eighty percent of students who have learning disabilities have dyslexia. Many of the students who attended this camp have experienced repeated failure in the traditional school system, which emphasizes literacy with little attention to science. A number of science and engineering professors collaborated with this camp to build instructional modules that were delivered one hour per day, during two weeks of this five week summer camp (ten hours of hands-on physics instruction). Both quantitative and qualitative data were collected with respect to the impact that this camp had on students' understanding and interests in science. The results of these efforts will be presented.

Neural dissociation of phonological and visual attention span disorders in developmental dyslexia: FMRI evidence from two case reports.

PubMed

Peyrin, C; Lallier, M; Démonet, J F; Pernet, C; Baciu, M; Le Bas, J F; Valdois, S

2012-03-01

A dissociation between phonological and visual attention (VA) span disorders has been reported in dyslexic children. This study investigates whether this cognitively-based dissociation has a neurobiological counterpart through the investigation of two cases of developmental dyslexia. LL showed a phonological disorder but preserved VA span whereas FG exhibited the reverse pattern. During a phonological rhyme judgement task, LL showed decreased activation of the left inferior frontal gyrus whereas this region was activated at the level of the controls in FG. Conversely, during a visual categorization task, FG demonstrated decreased activation of the parietal lobules whereas these regions were activated in LL as in the controls. These contrasted patterns of brain activation thus mirror the cognitive disorders' dissociation. These findings provide the first evidence for an association between distinct brain mechanisms and distinct cognitive deficits in developmental dyslexia, emphasizing the importance of taking into account the heterogeneity of the reading disorder. Copyright © 2012 Elsevier Inc. All rights reserved.

The Cerebellum and Neurodevelopmental Disorders.

PubMed

Stoodley, Catherine J

2016-02-01

Cerebellar dysfunction is evident in several developmental disorders, including autism, attention deficit-hyperactivity disorder (ADHD), and developmental dyslexia, and damage to the cerebellum early in development can have long-term effects on movement, cognition, and affective regulation. Early cerebellar damage is often associated with poorer outcomes than cerebellar damage in adulthood, suggesting that the cerebellum is particularly important during development. Differences in cerebellar development and/or early cerebellar damage could impact a wide range of behaviors via the closed-loop circuits connecting the cerebellum with multiple cerebral cortical regions. Based on these anatomical circuits, behavioral outcomes should depend on which cerebro-cerebellar circuits are affected. Here, we briefly review cerebellar structural and functional differences in autism, ADHD, and developmental dyslexia, and discuss clinical outcomes following pediatric cerebellar damage. These data confirm the prediction that abnormalities in different cerebellar subregions produce behavioral symptoms related to the functional disruption of specific cerebro-cerebellar circuits. These circuits might also be crucial to structural brain development, as peri-natal cerebellar lesions have been associated with impaired growth of the contralateral cerebral cortex. The specific contribution of the cerebellum to typical development may therefore involve the optimization of both the structure and function of cerebro-cerebellar circuits underlying skill acquisition in multiple domains; when this process is disrupted, particularly in early development, there could be long-term alterations of these neural circuits, with significant impacts on behavior.

The cerebellum and neurodevelopmental disorders

PubMed Central

Stoodley, Catherine J.

2015-01-01

Cerebellar dysfunction is evident in several developmental disorders, including autism, attention deficit hyperactivity disorder (ADHD), and developmental dyslexia, and damage to the cerebellum early in development can have long-term effects on movement, cognition, and affective regulation. Early cerebellar damage is often associated with poorer outcomes than cerebellar damage in adulthood, suggesting that the cerebellum is particularly important during development. Differences in cerebellar development and/or early cerebellar damage could impact a wide range of behaviors via the closed-loop circuits connecting the cerebellum with multiple cerebral cortical regions. Based on these anatomical circuits, behavioral outcomes should depend on which cerebro-cerebellar circuits are affected. Here, we briefly review cerebellar structural and functional differences in autism, ADHD, and developmental dyslexia, and discuss clinical outcomes following pediatric cerebellar damage. These data confirm the prediction that abnormalities in different cerebellar subregions produce behavioral symptoms related to the functional disruption of specific cerebro-cerebellar circuits. These circuits might also be crucial to structural brain development, as peri-natal cerebellar lesions have been associated with impaired growth of the contralateral cerebral cortex. The specific contribution of the cerebellum to typical development may therefore involve the optimization of both the structure and function of cerebro-cerebellar circuits underlying skill acquisition in multiple domains; when this process is disrupted, particularly in early development, there could be long-term alterations of these neural circuits, with significant impacts on behavior. PMID:26298473

Multiple Causal Links Between Magnocellular-Dorsal Pathway Deficit and Developmental Dyslexia.

PubMed

Gori, Simone; Seitz, Aaron R; Ronconi, Luca; Franceschini, Sandro; Facoetti, Andrea

2016-10-17

Although impaired auditory-phonological processing is the most popular explanation of developmental dyslexia (DD), the literature shows that the combination of several causes rather than a single factor contributes to DD. Functioning of the visual magnocellular-dorsal (MD) pathway, which plays a key role in motion perception, is a much debated, but heavily suspected factor contributing to DD. Here, we employ a comprehensive approach that incorporates all the accepted methods required to test the relationship between the MD pathway dysfunction and DD. The results of 4 experiments show that (1) Motion perception is impaired in children with dyslexia in comparison both with age-match and with reading-level controls; (2) pre-reading visual motion perception-independently from auditory-phonological skill-predicts future reading development, and (3) targeted MD trainings-not involving any auditory-phonological stimulation-leads to improved reading skill in children and adults with DD. Our findings demonstrate, for the first time, a causal relationship between MD deficits and DD, virtually closing a 30-year long debate. Since MD dysfunction can be diagnosed much earlier than reading and language disorders, our findings pave the way for low resource-intensive, early prevention programs that could drastically reduce the incidence of DD. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Disruption of functional networks in dyslexia: a whole-brain, data-driven analysis of connectivity.

PubMed

Finn, Emily S; Shen, Xilin; Holahan, John M; Scheinost, Dustin; Lacadie, Cheryl; Papademetris, Xenophon; Shaywitz, Sally E; Shaywitz, Bennett A; Constable, R Todd

2014-09-01

Functional connectivity analyses of functional magnetic resonance imaging data are a powerful tool for characterizing brain networks and how they are disrupted in neural disorders. However, many such analyses examine only one or a small number of a priori seed regions. Studies that consider the whole brain frequently rely on anatomic atlases to define network nodes, which might result in mixing distinct activation time-courses within a single node. Here, we improve upon previous methods by using a data-driven brain parcellation to compare connectivity profiles of dyslexic (DYS) versus non-impaired (NI) readers in the first whole-brain functional connectivity analysis of dyslexia. Whole-brain connectivity was assessed in children (n = 75; 43 NI, 32 DYS) and adult (n = 104; 64 NI, 40 DYS) readers. Compared to NI readers, DYS readers showed divergent connectivity within the visual pathway and between visual association areas and prefrontal attention areas; increased right-hemisphere connectivity; reduced connectivity in the visual word-form area (part of the left fusiform gyrus specialized for printed words); and persistent connectivity to anterior language regions around the inferior frontal gyrus. Together, findings suggest that NI readers are better able to integrate visual information and modulate their attention to visual stimuli, allowing them to recognize words on the basis of their visual properties, whereas DYS readers recruit altered reading circuits and rely on laborious phonology-based "sounding out" strategies into adulthood. These results deepen our understanding of the neural basis of dyslexia and highlight the importance of synchrony between diverse brain regions for successful reading. © 2013 Society of Biological Psychiatry Published by Society of Biological Psychiatry All rights reserved.

Evidence for reading improvement following tDCS treatment in children and adolescents with Dyslexia.

PubMed

Costanzo, Floriana; Varuzza, Cristiana; Rossi, Serena; Sdoia, Stefano; Varvara, Pamela; Oliveri, Massimiliano; Giacomo, Koch; Vicari, Stefano; Menghini, Deny

2016-01-01

There is evidence that non-invasive brain stimulation transitorily modulates reading by facilitating the neural pathways underactive in individuals with dyslexia. The study aimed at investigating whether multiple sessions of transcranial direct current stimulation (tDCS) would enhance reading abilities of children and adolescents with dyslexia and whether the effect is long-lasting. Eighteen children and adolescents with dyslexia received three 20-minute sessions a week for 6 weeks (18 sessions) of left anodal/right cathodal tDCS set at 1 mA over parieto-temporal regions combined with a cognitive training. The participants were randomly assigned to the active or the sham treatment; reading tasks (text, high and low frequency words, non-words) were used as outcome measures and collected before treatment, after treatment and one month after the end of treatment. The tolerability of tDCS was evaluated. The active group showed reduced low frequency word reading errors and non-word reading times. These positive effects were stable even one month after the end of treatment. None reported adverse effects. The study shows preliminary evidence of tDCS feasibility and efficacy in improving non-words and low frequency words reading of children and adolescents with dyslexia and it opens new rehabilitative perspectives for the remediation of dyslexia.

Dyslexia risk gene relates to representation of sound in the auditory brainstem.

PubMed

Neef, Nicole E; Müller, Bent; Liebig, Johanna; Schaadt, Gesa; Grigutsch, Maren; Gunter, Thomas C; Wilcke, Arndt; Kirsten, Holger; Skeide, Michael A; Kraft, Indra; Kraus, Nina; Emmrich, Frank; Brauer, Jens; Boltze, Johannes; Friederici, Angela D

2017-04-01

Dyslexia is a reading disorder with strong associations with KIAA0319 and DCDC2. Both genes play a functional role in spike time precision of neurons. Strikingly, poor readers show an imprecise encoding of fast transients of speech in the auditory brainstem. Whether dyslexia risk genes are related to the quality of sound encoding in the auditory brainstem remains to be investigated. Here, we quantified the response consistency of speech-evoked brainstem responses to the acoustically presented syllable [da] in 159 genotyped, literate and preliterate children. When controlling for age, sex, familial risk and intelligence, partial correlation analyses associated a higher dyslexia risk loading with KIAA0319 with noisier responses. In contrast, a higher risk loading with DCDC2 was associated with a trend towards more stable responses. These results suggest that unstable representation of sound, and thus, reduced neural discrimination ability of stop consonants, occurred in genotypes carrying a higher amount of KIAA0319 risk alleles. Current data provide the first evidence that the dyslexia-associated gene KIAA0319 can alter brainstem responses and impair phoneme processing in the auditory brainstem. This brain-gene relationship provides insight into the complex relationships between phenotype and genotype thereby improving the understanding of the dyslexia-inherent complex multifactorial condition. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Investigating the Influences of Language Delay and/or Familial Risk for Dyslexia on Brain Structure in 5-Year-Olds

PubMed Central

Raschle, Nora Maria; Becker, Bryce Larkin Chessell; Smith, Sara; Fehlbaum, Lynn Valérie; Wang, Yingying; Gaab, Nadine

2017-01-01

Abstract Early language delay has often been associated with atypical language/literacy development. Neuroimaging studies further indicate functional disruptions during language and print processing in school-age children with a retrospective report of early language delay. Behavioral data of 114 5-year-olds with a retrospective report of early language delay in infancy (N = 34) and those without (N = 80) and with a familial risk for dyslexia and those without are presented. Behaviorally, children with a retrospective report of early language delay exhibited reduced performance in language/reading-related measures. A voxel-based morphometry analysis in a subset (N = 46) demonstrated an association between reduced gray matter volume and early language delay in left-hemispheric middle temporal, occipital, and frontal regions. Alterations in middle temporal cortex in children with a retrospective report of early language delay were observed regardless of familial risk for dyslexia. Additionally, while children with isolated familial risk for dyslexia showed gray matter reductions in temporoparietal and occipitotemporal regions, these effects were most profound in children with both risk factors. An interaction effect of early language delay and familial risk was revealed in temporoparietal, occipital, and frontal cortex. Our findings support a cumulative effect of early behavioral and genetic risk factors on brain development and may ultimately inform diagnosis/treatment. PMID:26585334

Seeking a unified framework for cerebellar function and dysfunction: from circuit operations to cognition

PubMed Central

D'Angelo, Egidio; Casali, Stefano

2013-01-01

Following the fundamental recognition of its involvement in sensory-motor coordination and learning, the cerebellum is now also believed to take part in the processing of cognition and emotion. This hypothesis is recurrent in numerous papers reporting anatomical and functional observations, and it requires an explanation. We argue that a similar circuit structure in all cerebellar areas may carry out various operations using a common computational scheme. On the basis of a broad review of anatomical data, it is conceivable that the different roles of the cerebellum lie in the specific connectivity of the cerebellar modules, with motor, cognitive, and emotional functions (at least partially) segregated into different cerebro-cerebellar loops. We here develop a conceptual and operational framework based on multiple interconnected levels (a meta-levels hypothesis): from cellular/molecular to network mechanisms leading to generation of computational primitives, thence to high-level cognitive/emotional processing, and finally to the sphere of mental function and dysfunction. The main concept explored is that of intimate interplay between timing and learning (reminiscent of the “timing and learning machine” capabilities long attributed to the cerebellum), which reverberates from cellular to circuit mechanisms. Subsequently, integration within large-scale brain loops could generate the disparate cognitive/emotional and mental functions in which the cerebellum has been implicated. We propose, therefore, that the cerebellum operates as a general-purpose co-processor, whose effects depend on the specific brain centers to which individual modules are connected. Abnormal functioning in these loops could eventually contribute to the pathogenesis of major brain pathologies including not just ataxia but also dyslexia, autism, schizophrenia, and depression. PMID:23335884

Neural Biomarkers for Dyslexia, ADHD, and ADD in the Auditory Cortex of Children.

PubMed

Serrallach, Bettina; Groß, Christine; Bernhofs, Valdis; Engelmann, Dorte; Benner, Jan; Gündert, Nadine; Blatow, Maria; Wengenroth, Martina; Seitz, Angelika; Brunner, Monika; Seither, Stefan; Parncutt, Richard; Schneider, Peter; Seither-Preisler, Annemarie

2016-01-01

Dyslexia, attention deficit hyperactivity disorder (ADHD), and attention deficit disorder (ADD) show distinct clinical profiles that may include auditory and language-related impairments. Currently, an objective brain-based diagnosis of these developmental disorders is still unavailable. We investigated the neuro-auditory systems of dyslexic, ADHD, ADD, and age-matched control children (N = 147) using neuroimaging, magnetencephalography and psychoacoustics. All disorder subgroups exhibited an oversized left planum temporale and an abnormal interhemispheric asynchrony (10-40 ms) of the primary auditory evoked P1-response. Considering right auditory cortex morphology, bilateral P1 source waveform shapes, and auditory performance, the three disorder subgroups could be reliably differentiated with outstanding accuracies of 89-98%. We therefore for the first time provide differential biomarkers for a brain-based diagnosis of dyslexia, ADHD, and ADD. The method allowed not only allowed for clear discrimination between two subtypes of attentional disorders (ADHD and ADD), a topic controversially discussed for decades in the scientific community, but also revealed the potential for objectively identifying comorbid cases. Noteworthy, in children playing a musical instrument, after three and a half years of training the observed interhemispheric asynchronies were reduced by about 2/3, thus suggesting a strong beneficial influence of music experience on brain development. These findings might have far-reaching implications for both research and practice and enable a profound understanding of the brain-related etiology, diagnosis, and musically based therapy of common auditory-related developmental disorders and learning disabilities.

Neural Biomarkers for Dyslexia, ADHD, and ADD in the Auditory Cortex of Children

PubMed Central

Serrallach, Bettina; Groß, Christine; Bernhofs, Valdis; Engelmann, Dorte; Benner, Jan; Gündert, Nadine; Blatow, Maria; Wengenroth, Martina; Seitz, Angelika; Brunner, Monika; Seither, Stefan; Parncutt, Richard; Schneider, Peter; Seither-Preisler, Annemarie

2016-01-01

Dyslexia, attention deficit hyperactivity disorder (ADHD), and attention deficit disorder (ADD) show distinct clinical profiles that may include auditory and language-related impairments. Currently, an objective brain-based diagnosis of these developmental disorders is still unavailable. We investigated the neuro-auditory systems of dyslexic, ADHD, ADD, and age-matched control children (N = 147) using neuroimaging, magnetencephalography and psychoacoustics. All disorder subgroups exhibited an oversized left planum temporale and an abnormal interhemispheric asynchrony (10–40 ms) of the primary auditory evoked P1-response. Considering right auditory cortex morphology, bilateral P1 source waveform shapes, and auditory performance, the three disorder subgroups could be reliably differentiated with outstanding accuracies of 89–98%. We therefore for the first time provide differential biomarkers for a brain-based diagnosis of dyslexia, ADHD, and ADD. The method allowed not only allowed for clear discrimination between two subtypes of attentional disorders (ADHD and ADD), a topic controversially discussed for decades in the scientific community, but also revealed the potential for objectively identifying comorbid cases. Noteworthy, in children playing a musical instrument, after three and a half years of training the observed interhemispheric asynchronies were reduced by about 2/3, thus suggesting a strong beneficial influence of music experience on brain development. These findings might have far-reaching implications for both research and practice and enable a profound understanding of the brain-related etiology, diagnosis, and musically based therapy of common auditory-related developmental disorders and learning disabilities. PMID:27471442

Neuroanatomical anomalies of dyslexia: Disambiguating the effects of disorder, performance, and maturation.

PubMed

Xia, Zhichao; Hoeft, Fumiko; Zhang, Linjun; Shu, Hua

2016-01-29

An increasing body of studies has revealed neuroanatomical impairments in developmental dyslexia. However, whether these structural anomalies are driven by dyslexia (disorder-specific effects), absolute reading performance (performance-dependent effects), and/or further influenced by age (maturation-sensitive effects) remains elusive. To help disentangle these sources, the current study used a novel disorder (dyslexia vs. control) by maturation (younger vs. older) factorial design in 48 Chinese children who were carefully matched. This design not only allows for direct comparison between dyslexics versus controls matched for chronological age and reading ability, but also enables examination of the influence of maturation and its interaction with dyslexia. Voxel-based morphometry (VBM) showed that dyslexic children had reduced regional gray matter volume in the left temporo-parietal cortex (spanning over Heschl's gyrus, planum temporale and supramarginal gyrus), middle frontal gyrus, superior occipital gyrus, and reduced regional white matter in bilateral parieto-occipital regions (left cuneus and right precuneus) compared with both age-matched and reading-level matched controls. Therefore, maturational stage-invariant neurobiological signatures of dyslexia were found in brain regions that have been associated with impairments in the auditory/phonological and attentional systems. On the other hand, maturational stage-dependent effects on dyslexia were observed in three regions (left ventral occipito-temporal cortex, left dorsal pars opercularis and genu of the corpus callosum), all of which were previously reported to be involved in fluent reading and its development. These striking dissociations collectively suggest potential atypical developmental trajectories of dyslexia, where underlying mechanisms are currently unknown but may be driven by interactions between genetic and/or environmental factors. In summary, this is the first study to disambiguate maturational stage on neuroanatomical anomalies of dyslexia in addition to the effects of disorder, reading performance and maturational stage on neuroanatomical anomalies of dyslexia, despite the limitation of a relatively small sample-size. These results will hopefully encourage future research to place greater emphasis on taking a developmental perspective to dyslexia, which may, in turn, further our understanding of the etiological basis of this neurodevelopmental disorder, and ultimately optimize early identification and remediation. Copyright © 2015 Elsevier Ltd. All rights reserved.

Neuroanatomical Anomalies of Dyslexia: Disambiguating the Effects of Disorder, Performance, and Maturation

PubMed Central

Xia, Zhichao; Hoeft, Fumiko; Zhang, Linjun; Shu, Hua

2016-01-01

An increasing body of studies has revealed neuroanatomical impairments in developmental dyslexia. However, whether these structural anomalies are driven by dyslexia (disorder-specific effects), absolute reading performance (performance-dependent effects), and/or further influenced by age (maturation-sensitive effects) remains elusive. To help disentangle these sources, the current study used a novel disorder (dyslexia vs. control) by maturation (younger vs. older) factorial design in 48 Chinese children who were carefully matched. This design not only allows for direct comparison between dyslexics versus controls matched for chronological age and reading ability, but also enables examination of the influence of maturation and its interaction with dyslexia. Voxel-based morphometry (VBM) showed that dyslexic children had reduced regional gray matter volume in the left temporo-parietal cortex (spanning over Heschl’s gyrus, planum temporale and supramarginal gyrus), middle frontal gyrus, superior occipital gyrus, and reduced regional white matter in bilateral parieto-occipital regions (left cuneus and right precuneus) compared with both age-matched and reading-level matched controls. Therefore, maturational stage-invariant neurobiological signatures of dyslexia were found in brain regions that have been associated with impairments in the auditory/phonological and attentional systems. On the other hand, maturational stage-dependent effects on dyslexia were observed in three regions (left ventral occipito-temporal cortex, left dorsal pars opercularis and genu of the corpus callosum), all of which were previously reported to be involved in fluent reading and its development. These striking dissociations collectively suggest potential atypical developmental trajectories of dyslexia, where underlying mechanisms are currently unknown but may be driven by interactions between genetic and/or environmental factors. In summary, this is the first study to disambiguate maturational stage on neuroanatomical anomalies of dyslexia in addition to the effects of disorder, reading performance and maturational stage on neuroanatomical anomalies of dyslexia, despite the limitation of a relatively small sample-size. These results will hopefully encourage future research to place greater emphasis on taking a developmental perspective to dyslexia, which may, in turn, further our understanding of the etiological basis of this neurodevelopmental disorder, and ultimately optimize early identification and remediation. PMID:26679527

Contrasting brain patterns of writing-related DTI parameters, fMRI connectivity, and DTI-fMRI connectivity correlations in children with and without dysgraphia or dyslexia.

PubMed

Richards, T L; Grabowski, T J; Boord, P; Yagle, K; Askren, M; Mestre, Z; Robinson, P; Welker, O; Gulliford, D; Nagy, W; Berninger, V

2015-01-01

Based on comprehensive testing and educational history, children in grades 4-9 (on average 12 years) were diagnosed with dysgraphia (persisting handwriting impairment) or dyslexia (persisting word spelling/reading impairment) or as typical writers and readers (controls). The dysgraphia group (n = 14) and dyslexia group (n = 17) were each compared to the control group (n = 9) and to each other in separate analyses. Four brain region seed points (left occipital temporal gyrus, supramarginal gyrus, precuneus, and inferior frontal gyrus) were used in these analyses which were shown in a metaanalysis to be related to written word production on four indicators of white matter integrity and fMRI functional connectivity for four tasks (self-guided mind wandering during resting state, writing letter that follows a visually displayed letter in alphabet, writing missing letter to create a correctly spelled real word, and planning for composing after scanning on topic specified by researcher). For those DTI indicators on which the dysgraphic group or dyslexic group differed from the control group (fractional anisotropy, relative anisotropy, axial diffusivity but not radial diffusivity), correlations were computed between the DTI parameter and fMRI functional connectivity for the two writing tasks (alphabet and spelling) by seed points. Analyses, controlled for multiple comparisons, showed that (a) the control group exhibited more white matter integrity than either the dysgraphic or dyslexic group; (b) the dysgraphic and dyslexic groups showed more functional connectivity than the control group but differed in patterns of functional connectivity for task and seed point; and (c) the dysgraphic and dyslexic groups showed different patterns of significant DTI-fMRI connectivity correlations for specific seed points and written language tasks. Thus, dysgraphia and dyslexia differ in white matter integrity, fMRI functional connectivity, and white matter-gray matter correlations. Of clinical relevance, brain differences were observed in dysgraphia and dyslexia on written language tasks yoked to their defining behavioral impairments in handwriting and/or in word spelling and on the cognitive mind wandering rest condition and composition planning.

Contrasting brain patterns of writing-related DTI parameters, fMRI connectivity, and DTI–fMRI connectivity correlations in children with and without dysgraphia or dyslexia

PubMed Central

Richards, T.L.; Grabowski, T.J.; Boord, P.; Yagle, K.; Askren, M.; Mestre, Z.; Robinson, P.; Welker, O.; Gulliford, D.; Nagy, W.; Berninger, V.

2015-01-01

Based on comprehensive testing and educational history, children in grades 4–9 (on average 12 years) were diagnosed with dysgraphia (persisting handwriting impairment) or dyslexia (persisting word spelling/reading impairment) or as typical writers and readers (controls). The dysgraphia group (n = 14) and dyslexia group (n = 17) were each compared to the control group (n = 9) and to each other in separate analyses. Four brain region seed points (left occipital temporal gyrus, supramarginal gyrus, precuneus, and inferior frontal gyrus) were used in these analyses which were shown in a metaanalysis to be related to written word production on four indicators of white matter integrity and fMRI functional connectivity for four tasks (self-guided mind wandering during resting state, writing letter that follows a visually displayed letter in alphabet, writing missing letter to create a correctly spelled real word, and planning for composing after scanning on topic specified by researcher). For those DTI indicators on which the dysgraphic group or dyslexic group differed from the control group (fractional anisotropy, relative anisotropy, axial diffusivity but not radial diffusivity), correlations were computed between the DTI parameter and fMRI functional connectivity for the two writing tasks (alphabet and spelling) by seed points. Analyses, controlled for multiple comparisons, showed that (a) the control group exhibited more white matter integrity than either the dysgraphic or dyslexic group; (b) the dysgraphic and dyslexic groups showed more functional connectivity than the control group but differed in patterns of functional connectivity for task and seed point; and (c) the dysgraphic and dyslexic groups showed different patterns of significant DTI–fMRI connectivity correlations for specific seed points and written language tasks. Thus, dysgraphia and dyslexia differ in white matter integrity, fMRI functional connectivity, and white matter–gray matter correlations. Of clinical relevance, brain differences were observed in dysgraphia and dyslexia on written language tasks yoked to their defining behavioral impairments in handwriting and/or in word spelling and on the cognitive mind wandering rest condition and composition planning. PMID:26106566

Experimental induction of reading difficulties in normal readers provides novel insights into the neurofunctional mechanisms of visual word recognition.

PubMed

Heim, Stefan; Weidner, Ralph; von Overheidt, Ann-Christin; Tholen, Nicole; Grande, Marion; Amunts, Katrin

2014-03-01

Phonological and visual dysfunctions may result in reading deficits like those encountered in developmental dyslexia. Here, we use a novel approach to induce similar reading difficulties in normal readers in an event-related fMRI study, thus systematically investigating which brain regions relate to different pathways relating to orthographic-phonological (e.g. grapheme-to-phoneme conversion, GPC) vs. visual processing. Based upon a previous behavioural study (Tholen et al. 2011), the retrieval of phonemes from graphemes was manipulated by lowering the identifiability of letters in familiar vs. unfamiliar shapes. Visual word and letter processing was impeded by presenting the letters of a word in a moving, non-stationary manner. FMRI revealed that the visual condition activated cytoarchitectonically defined area hOC5 in the magnocellular pathway and area 7A in the right mesial parietal cortex. In contrast, the grapheme manipulation revealed different effects localised predominantly in bilateral inferior frontal gyrus (left cytoarchitectonic area 44; right area 45) and inferior parietal lobule (including areas PF/PFm), regions that have been demonstrated to show abnormal activation in dyslexic as compared to normal readers. This pattern of activation bears close resemblance to recent findings in dyslexic samples both behaviourally and with respect to the neurofunctional activation patterns. The novel paradigm may thus prove useful in future studies to understand reading problems related to distinct pathways, potentially providing a link also to the understanding of real reading impairments in dyslexia.

Neurological Processes and Reading Pathology: Knowing About Children and Reading Dysfunction.

ERIC Educational Resources Information Center

Roberts, David Harrill

For many years dyslexia has been incorrectly applied to those who have demonstrated difficulty in learning to read. Given the proper guidance and opportunities for becoming sensitive to demonstrations of the workings of language and engaging their minds in learning, many students will overcome their so-called learning disabilities. However, there…

Civilian Health and Medical Program of the Uniformed Services (CHAMPUS). Change 6

DTIC Science & Technology

1994-06-24

Exception to general exclusion. 4-31c b. Limitations. 4-32 7. Transsexualism or hermaphroditism. 4-32 8. Cosmetic, reconstructive, or plastic surgery. 4... Transsexualism or hermaphroditism. 4-49 30. Sexual dysfunctions or inadequacies. 4-49 31. Corns, calluses, and toenails. 4-49 32. Dyslexia. 4-49 33

Paying attention to reading: the neurobiology of reading and dyslexia.

PubMed

Shaywitz, Sally E; Shaywitz, Bennett A

2008-01-01

Extraordinary progress in functional brain imaging, primarily advances in functional magnetic resonance imaging, now allows scientists to understand the neural systems serving reading and how these systems differ in dyslexic readers. Scientists now speak of the neural signature of dyslexia, a singular achievement that for the first time has made what was previously a hidden disability, now visible. Paralleling this achievement in understanding the neurobiology of dyslexia, progress in the identification and treatment of dyslexia now offers the hope of identifying children at risk for dyslexia at a very young age and providing evidence-based, effective interventions. Despite these advances, for many dyslexic readers, becoming a skilled, automatic reader remains elusive, in great part because though children with dyslexia can be taught to decode words, teaching children to read fluently and automatically represents the next frontier in research on dyslexia. We suggest that to break through this "fluency" barrier, investigators will need to reexamine the more than 20-year-old central dogma in reading research: the generation of the phonological code from print is modular, that is, automatic and not attention demanding, and not requiring any other cognitive process. Recent findings now present a competing view: other cognitive processes are involved in reading, particularly attentional mechanisms, and that disruption of these attentional mechanisms play a causal role in reading difficulties. Recognition of the role of attentional mechanisms in reading now offer potentially new strategies for interventions in dyslexia. In particular, the use of pharmacotherapeutic agents affecting attentional mechanisms not only may provide a window into the neurochemical mechanisms underlying dyslexia but also may offer a potential adjunct treatment for teaching dyslexic readers to read fluently and automatically. Preliminary studies suggest that agents traditionally used to treat disorders of attention, particularly attention-deficit/hyperactivity disorder, may prove to be an effective adjunct to improving reading in dyslexic students.

Functional Neuroanatomical Evidence for the Double-Deficit Hypothesis of Developmental Dyslexia

PubMed Central

Norton, Elizabeth S.; Black, Jessica M.; Stanley, Leanne M.; Tanaka, Hiroko; Gabrieli, John D. E.; Sawyer, Carolyn; Hoeft, Fumiko

2015-01-01

The double-deficit hypothesis of dyslexia posits that both rapid naming and phonological impairments can cause reading difficulties, and that individuals who have both of these deficits show greater reading impairments compared to those with a single deficit. Despite extensive behavioral research, the brain basis of poor reading with a double-deficit has never been investigated. The goal of the study was to evaluate the double-deficit hypothesis using functional MRI. Activation patterns during a printed word rhyme judgment task in 90 children with a wide range of reading abilities showed dissociation between brain regions that were sensitive to phonological awareness (left inferior frontal and inferior parietal regions) and rapid naming (right cerebellar lobule VI). More specifically, the double-deficit group showed less activation in the fronto-parietal reading network compared to children with only a deficit in phonological awareness, who in turn showed less activation than the typically-reading group. On the other hand, the double-deficit group showed less cerebellar activation compared to children with only a rapid naming deficit, who in turn showed less activation than the typically-reading children. Functional connectivity analyses revealed that bilateral prefrontal regions were key for linking brain regions associated with phonological awareness and rapid naming, with the double-deficit group being the most aberrant in their connectivity. Our study provides the first functional neuroanatomical evidence for the double-deficit hypothesis of developmental dyslexia. PMID:24953957

Education Influences Creativity in Dyslexic and Non-Dyslexic Children and Teenagers.

PubMed

Kapoula, Zoï; Ruiz, Sarah; Spector, Lisa; Mocorovi, Marion; Gaertner, Chrystal; Quilici, Catherine; Vernet, Marine

2016-01-01

Are dyslexic children and teenagers more creative than non-dyslexic children and teenagers? Whether creativity is higher in dyslexia, and whether this could be related to neurological development specific to the dyslexic disorder, or to compensatory strategies acquired later in life, remains unclear. Here, we suggest an additional role of differential educational approaches taken in each school that could either enhance or suppress an already higher baseline creativity of dyslexic children and teenagers. Creativity in dyslexic and non-dyslexic children and teenagers from different schools in France and in Belgium, as well as in students from different universities, was evaluated with the Torrance Test of Creative Thinking (TTCT). Children and teenagers with dyslexia and/or with other similar dysfunctions showed higher creativity scores than non-dyslexic participants. Moreover, the educational approach could further enhance the creative scores in dyslexia, which could be as high as those measured in students from art universities. We conclude that dyslexic children and teenagers can be highly creative. Yet, expression of creativity can be modulated by educational approach, indicating a probable advantage for personal follow-up compared to normalizing education strategies.

Long-lasting improvement following tDCS treatment combined with a training for reading in children and adolescents with dyslexia.

PubMed

Costanzo, Floriana; Rossi, Serena; Varuzza, Cristiana; Varvara, Pamela; Vicari, Stefano; Menghini, Deny

2018-03-14

Noninvasive brain stimulation transiently modulates reading ability in individuals with dyslexia by facilitating the underactive neural pathways in them. However, its long-term effects have not been determined. This study confirmed the ameliorative effects of multiple sessions of transcranial direct current stimulation (tDCS) combined with a training for reading on the reading abilities of children and adolescents with dyslexia and examined whether they are long-lasting. Twenty-six children and adolescents with dyslexia received 3 20-min sessions per week for 6 weeks (18 sessions) of left anodal/right cathodal tDCS, set to 1 mA, over the parieto-temporal regions, combined with training for reading. The participants were randomly assigned to receive active or sham treatment. Reading measures (text, high- and low-frequency words, non-words) were recorded before and immediately after the treatment and 1 and 6 months later. The long-term tolerability to tDCS was also evaluated. The active group received long-lasting benefits in reading. Specifically, the non-word reading efficiency index improved at every time point, as did the low-frequency word reading efficiency index at 1 and 6 months after the end of the treatment. No differences emerged in the sham group. No long-term adverse effects were documented. This study provides evidence of persistent improvements in reading in children and adolescents with dyslexia, constituting a new rehabilitative approach for the remediation of dyslexia. Copyright © 2018 Elsevier Ltd. All rights reserved.

Evaluation of ocular movements in patients with dyslexia.

PubMed

Vagge, Aldo; Cavanna, Margherita; Traverso, Carlo Enrico; Iester, Michele

2015-04-01

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 examinations, and eye movement analysis, specifically, stability analysis on fixating a still target, tracking saccades, analysis of fixation pauses, speed reading, saccades, and regressions through the reading of a text. Stability analysis on fixating a still target showed a significant (p < 0.001) difference between the two groups showing an increased amount of loss of fixation among dyslexic subjects (5.36 ± 2.5 s and 0.82 ± 2.1, respectively). Tracking saccades (left and right horizontal axis) did not show a significant difference. When reading parameters were looked into (number of saccades, number of regressions, reading time through the reading of a text), a significant (p < 0.001) difference was found between the groups. This study supports the belief that the alteration of eye movement does not depend on oculo-motor dysfunction but is secondary to a defect in the visual processing of linguistic material. Inclusion of assessment of this defect might prove beneficial in determining the presence of dyslexia in young children at a younger age, and an earlier intervention could be initiated.

An Evo-Devo Approach to Thyroid Hormones in Cerebral and Cerebellar Cortical Development: Etiological Implications for Autism

PubMed Central

Berbel, Pere; Navarro, Daniela; Román, Gustavo C.

2014-01-01

The morphological alterations of cortical lamination observed in mouse models of developmental hypothyroidism prompted the recognition that these experimental changes resembled the brain lesions of children with autism; this led to recent studies showing that maternal thyroid hormone deficiency increases fourfold the risk of autism spectrum disorders (ASD), offering for the first time the possibility of prevention of some forms of ASD. For ethical reasons, the role of thyroid hormones on brain development is currently studied using animal models, usually mice and rats. Although mammals have in common many basic developmental principles regulating brain development, as well as fundamental basic mechanisms that are controlled by similar metabolic pathway activated genes, there are also important differences. For instance, the rodent cerebral cortex is basically a primary cortex, whereas the primary sensory areas in humans account for a very small surface in the cerebral cortex when compared to the associative and frontal areas that are more extensive. Associative and frontal areas in humans are involved in many neurological disorders, including ASD, attention deficit-hyperactive disorder, and dyslexia, among others. Therefore, an evo-devo approach to neocortical evolution among species is fundamental to understand not only the role of thyroid hormones and environmental thyroid disruptors on evolution, development, and organization of the cerebral cortex in mammals but also their role in neurological diseases associated to thyroid dysfunction. PMID:25250016

The effects of Kiaa0319 knockdown on cortical and subcortical anatomy in male rats

PubMed Central

Szalkowski, Caitlin E.; Fiondella, Christopher F.; Truong, Dongnhu T.; Rosen, Glenn D.; LoTurco, Joseph J.; Fitch, Roslyn H.

2012-01-01

Developmental dyslexia is a disorder characterized by a specific deficit in reading despite adequate overall intelligence and educational resources. The neurological substrate underlying these significant behavioral impairments is not known. Studies of post mortem brain tissue from male and female dyslexic individuals revealed focal disruptions of neuronal migration concentrated in the left hemisphere, along with aberrant symmetry of the right and left the planum temporale, and changes in cell size distribution within the medial geniculate nucleus of the thalamus (Galaburda et al., 1985; Humphreys et al., 1990). More recent neuroimaging studies have identified several changes in the brains of dyslexic individuals, including regional changes in gray matter, changes in white matter, and changes in patterns of functional activation. In a further effort to elucidate the etiology of dyslexia, epidemiological and genetic studies have identified several candidate dyslexia susceptibility genes. Some recent work has investigated associations between some of these genetic variants and structural changes in the brain. Variants of one candidate dyslexia susceptibility gene, KIAA0319, have been linked to morphological changes in the cerebellum and functional activational changes in the superior temporal sulcus (Jamadar et al., 2011; Pinel et al., 2012). Animal models have been used to create a knockdown of Kiaa0319 (the rodent homolog of the human gene) via in utero RNA interference in order to study the gene’s effects on brain development and behavior. Studies using this animal model have demonstrated that knocking down the gene leads to focal disruptions of neuronal migration in the form of ectopias and heterotopias, similar to those observed in the brains of human dyslexics. However, further changes to the structure of the brain have not been studied following this genetic disruption. The current study sought to determine the effects of embryonic Kiaa0319 knockdown on volume of the cortex and hippocampus, as well as midsagittal area of the corpus callosum in male rats. Results demonstrate that Kiaa0319 knockdown did not change the volume of the cortex or hippocampus, but did result in a significant reduction in the midsagittal area of the corpus callosum. Taken in the context of previous reports of behavioral deficits following Kiaa0319 knockdown (Szalkowski et al., 2012), and reports that reductions of corpus callosum size are related to processing deficits in humans (Paul et al., 2011), these results suggest that Kiaa0319 has a specific involvement in neural systems important for temporal processing. PMID:23220223

Slow perceptual processing at the core of developmental dyslexia: a parameter-based assessment of visual attention.

PubMed

Stenneken, Prisca; Egetemeir, Johanna; Schulte-Körne, Gerd; Müller, Hermann J; Schneider, Werner X; Finke, Kathrin

2011-10-01

The cognitive causes as well as the neurological and genetic basis of developmental dyslexia, a complex disorder of written language acquisition, are intensely discussed with regard to multiple-deficit models. Accumulating evidence has revealed dyslexics' impairments in a variety of tasks requiring visual attention. The heterogeneity of these experimental results, however, points to the need for measures that are sufficiently sensitive to differentiate between impaired and preserved attentional components within a unified framework. This first parameter-based group study of attentional components in developmental dyslexia addresses potentially altered attentional components that have recently been associated with parietal dysfunctions in dyslexia. We aimed to isolate the general attentional resources that might underlie reduced span performance, i.e., either a deficient working memory storage capacity, or a slowing in visual perceptual processing speed, or both. Furthermore, by analysing attentional selectivity in dyslexia, we addressed a potential lateralized abnormality of visual attention, i.e., a previously suggested rightward spatial deviation compared to normal readers. We investigated a group of high-achieving young adults with persisting dyslexia and matched normal readers in an experimental whole report and a partial report of briefly presented letter arrays. Possible deviations in the parametric values of the dyslexic compared to the control group were taken as markers for the underlying deficit. The dyslexic group showed a striking reduction in perceptual processing speed (by 26% compared to controls) while their working memory storage capacity was in the normal range. In addition, a spatial deviation of attentional weighting compared to the control group was confirmed in dyslexic readers, which was larger in participants with a more severe dyslexic disorder. In general, the present study supports the relevance of perceptual processing speed in disorders of written language acquisition and demonstrates that the parametric assessment provides a suitable tool for specifying the underlying deficit within a unitary framework. Copyright © 2011 Elsevier Ltd. All rights reserved.

Cortical Signatures of Dyslexia and Remediation: An Intrinsic Functional Connectivity Approach

PubMed Central

Koyama, Maki S.; Di Martino, Adriana; Kelly, Clare; Jutagir, Devika R.; Sunshine, Jessica; Schwartz, Susan J.; Castellanos, Francisco X.; Milham, Michael P.

2013-01-01

This observational, cross-sectional study investigates cortical signatures of developmental dyslexia, particularly from the perspective of behavioral remediation. We employed resting-state fMRI, and compared intrinsic functional connectivity (iFC) patterns of known reading regions (seeds) among three dyslexia groups characterized by (a) no remediation (current reading and spelling deficits), (b) partial remediation (only reading deficit remediated), and (c) full remediation (both reading and spelling deficits remediated), and a group of age- and IQ-matched typically developing children (TDC) (total N = 44, age range = 7–15 years). We observed significant group differences in iFC of two seeds located in the left posterior reading network – left intraparietal sulcus (L.IPS) and left fusiform gyrus (L.FFG). Specifically, iFC between L.IPS and left middle frontal gyrus was significantly weaker in all dyslexia groups, irrespective of remediation status/literacy competence, suggesting that persistent dysfunction in the fronto-parietal attention network characterizes dyslexia. Additionally, relative to both TDC and the no remediation group, the remediation groups exhibited stronger iFC between L.FFG and right middle occipital gyrus (R.MOG). The full remediation group also exhibited stronger negative iFC between the same L.FFG seed and right medial prefrontal cortex (R.MPFC), a core region of the default network These results suggest that behavioral remediation may be associated with compensatory changes anchored in L.FFG, which reflect atypically stronger coupling between posterior visual regions (L.FFG-R.MOG) and greater functional segregation between task-positive and task-negative regions (L.FFG-R.MPFC). These findings were bolstered by significant relationships between the strength of the identified functional connections and literacy scores. We conclude that examining iFC can reveal cortical signatures of dyslexia with particular promise for monitoring neural changes associated with behavioral remediation. PMID:23408984

Brain Connectivity in Non-Reading Impaired Children and Children Diagnosed with Developmental Dyslexia

ERIC Educational Resources Information Center

Odegard, Timothy N.; Farris, Emily A.; Ring, Jeremiah; McColl, Roderick; Black, Jeffrey

2009-01-01

Diffusion Tensor Imaging (DTI) was used to investigate the relationship between white matter and reading abilities in reading impaired and non-reading impaired children. Seventeen children (7 non-reading impaired, 10 reading impaired) participated in this study. DTI was performed with 2 mm isotropic resolution to cover the entire brain along 30…

Cognitive Brain Potentials in Kindergarten Children with Subtyped Risks of Reading Retardation

ERIC Educational Resources Information Center

Bakker, Dirk J.; Van Strien, Jan W.; Licht, Robert; Smit-Glaude, Sietsia W. D.

2007-01-01

Cognition-related brain responses to meaningful and meaningless figures were registered in 5-year-old kindergarten children who either had been subtyped as being at-risk of developing an L- or P-type dyslexia (LAL versus LAP) or who were not at-risk. While identifying, naming, or categorizing pictures, event-related potentials (ERP) were…

Increased Resting-State Functional Connectivity in the Cingulo-Opercular Cognitive-Control Network after Intervention in Children with Reading Difficulties

PubMed Central

Horowitz-Kraus, Tzipi; Toro-Serey, Claudio; DiFrancesco, Mark

2015-01-01

Dyslexia, or reading difficulty, is characterized by slow, inaccurate reading accompanied by executive dysfunction. Reading training using the Reading Acceleration Program improves reading and executive functions in both children with dyslexia and typical readers. This improvement is associated with increased activation in and functional connectivity between the anterior cingulate cortex, part of the cingulo-opercular cognitive-control network, and the fusiform gyrus during a reading task after training. The objective of the current study was to determine whether the training also has an effect on functional connectivity of the cingulo-opercular and fronto-parietal cognitive-control networks during rest in children with dyslexia and typical readers. Fifteen children with reading difficulty and 17 typical readers (8-12 years old) were included in the study. Reading and executive functions behavioral measures and resting-state functional magnetic resonance imaging data were collected before and after reading training. Imaging data were analyzed using a graphical network-modeling tool. Both reading groups had increased reading and executive-functions scores after training, with greater gains among the dyslexia group. Training may have less effect on cognitive control in typical readers and a more direct effect on the visual area, as previously reported. Statistical analysis revealed that compared to typical readers, children with reading difficulty had significantly greater functional connectivity in the cingulo-opercular network after training, which may demonstrate the importance of cognitive control during reading in this population. These results support previous findings of increased error-monitoring activation after reading training in children with dyslexia and confirm greater gains with training in this group. PMID:26197049

Lessons from the Reading Brain for Reading Development and Dyslexia

ERIC Educational Resources Information Center

Wolf, Maryanne; Ullman-Shade, Catherine; Gottwald, Stephanie

2016-01-01

This essay is about the improbable emergence of written language six millennia ago that gave rise to the even more improbable, highly sophisticated reading brain of the twenty-first century. How it emerged and what it comprises--both in its most basic iteration in the very young reader and in its most elaborated iteration in the expert reader--is…

Music and Dyslexia: A New Musical Training Method to Improve Reading and Related Disorders

PubMed Central

Habib, Michel; Lardy, Chloé; Desiles, Tristan; Commeiras, Céline; Chobert, Julie; Besson, Mireille

2016-01-01

Numerous arguments in the recent neuroscientific literature support the use of musical training as a therapeutic tool among the arsenal already available to therapists and educators for treating children with dyslexia. In the present study, we tested the efficacy of a specially-designed Cognitivo-Musical Training (CMT) method based upon three principles: (1) music-language analogies: training dyslexics with music could contribute to improve brain circuits which are common to music and language processes; (2) the temporal and rhythmic features of music, which could exert a positive effect on the multiple dimensions of the “temporal deficit” characteristic of some types of dyslexia; and (3) cross-modal integration, based on converging evidence of impaired connectivity between brain regions in dyslexia and related disorders. Accordingly, we developed a series of musical exercises involving jointly and simultaneously sensory (visual, auditory, somatosensory) and motor systems, with special emphasis on rhythmic perception and production in addition to intensive training of various features of the musical auditory signal. Two separate studies were carried out, one in which dyslexic children received intensive musical exercises concentrated over 18 h during 3 consecutive days, and the other in which the 18 h of musical training were spread over 6 weeks. Both studies showed significant improvements in some untrained, linguistic and non-linguistic variables. The first one yielded significant improvement in categorical perception and auditory perception of temporal components of speech. The second study revealed additional improvements in auditory attention, phonological awareness (syllable fusion), reading abilities, and repetition of pseudo-words. Importantly, most improvements persisted after an untrained period of 6 weeks. These results provide new additional arguments for using music as part of systematic therapeutic and instructional practice for dyslexic children. PMID:26834689

Education Influences Creativity in Dyslexic and Non-Dyslexic Children and Teenagers

PubMed Central

Kapoula, Zoï; Ruiz, Sarah; Spector, Lisa; Mocorovi, Marion; Gaertner, Chrystal; Quilici, Catherine; Vernet, Marine

2016-01-01

Background and Study Hypothesis Are dyslexic children and teenagers more creative than non-dyslexic children and teenagers? Whether creativity is higher in dyslexia, and whether this could be related to neurological development specific to the dyslexic disorder, or to compensatory strategies acquired later in life, remains unclear. Here, we suggest an additional role of differential educational approaches taken in each school that could either enhance or suppress an already higher baseline creativity of dyslexic children and teenagers. Results Creativity in dyslexic and non-dyslexic children and teenagers from different schools in France and in Belgium, as well as in students from different universities, was evaluated with the Torrance Test of Creative Thinking (TTCT). Children and teenagers with dyslexia and/or with other similar dysfunctions showed higher creativity scores than non-dyslexic participants. Moreover, the educational approach could further enhance the creative scores in dyslexia, which could be as high as those measured in students from art universities. Conclusions We conclude that dyslexic children and teenagers can be highly creative. Yet, expression of creativity can be modulated by educational approach, indicating a probable advantage for personal follow-up compared to normalizing education strategies. PMID:26950067

Neurofeedback: A Comprehensive Review on System Design, Methodology and Clinical Applications.

PubMed

Marzbani, Hengameh; Marateb, Hamid Reza; Mansourian, Marjan

2016-04-01

Neurofeedback is a kind of biofeedback, which teaches self-control of brain functions to subjects by measuring brain waves and providing a feedback signal. Neurofeedback usually provides the audio and or video feedback. Positive or negative feedback is produced for desirable or undesirable brain activities, respectively. In this review, we provided clinical and technical information about the following issues: (1) Various neurofeedback treatment protocols i.e. alpha, beta, alpha/theta, delta, gamma, and theta; (2) Different EEG electrode placements i.e. standard recording channels in the frontal, temporal, central, and occipital lobes; (3) Electrode montages (unipolar, bipolar); (4) Types of neurofeedback i.e. frequency, power, slow cortical potential, functional magnetic resonance imaging, and so on; (5) Clinical applications of neurofeedback i.e. treatment of attention deficit hyperactivity disorder, anxiety, depression, epilepsy, insomnia, drug addiction, schizophrenia, learning disabilities, dyslexia and dyscalculia, autistic spectrum disorders and so on as well as other applications such as pain management, and the improvement of musical and athletic performance; and (6) Neurofeedback softwares. To date, many studies have been conducted on the neurofeedback therapy and its effectiveness on the treatment of many diseases. Neurofeedback, like other treatments, has its own pros and cons. Although it is a non-invasive procedure, its validity has been questioned in terms of conclusive scientific evidence. For example, it is expensive, time-consuming and its benefits are not long-lasting. Also, it might take months to show the desired improvements. Nevertheless, neurofeedback is known as a complementary and alternative treatment of many brain dysfunctions. However, current research does not support conclusive results about its efficacy.

Neurofeedback: A Comprehensive Review on System Design, Methodology and Clinical Applications

PubMed Central

Marzbani, Hengameh; Marateb, Hamid Reza; Mansourian, Marjan

2016-01-01

Neurofeedback is a kind of biofeedback, which teaches self-control of brain functions to subjects by measuring brain waves and providing a feedback signal. Neurofeedback usually provides the audio and or video feedback. Positive or negative feedback is produced for desirable or undesirable brain activities, respectively. In this review, we provided clinical and technical information about the following issues: (1) Various neurofeedback treatment protocols i.e. alpha, beta, alpha/theta, delta, gamma, and theta; (2) Different EEG electrode placements i.e. standard recording channels in the frontal, temporal, central, and occipital lobes; (3) Electrode montages (unipolar, bipolar); (4) Types of neurofeedback i.e. frequency, power, slow cortical potential, functional magnetic resonance imaging, and so on; (5) Clinical applications of neurofeedback i.e. treatment of attention deficit hyperactivity disorder, anxiety, depression, epilepsy, insomnia, drug addiction, schizophrenia, learning disabilities, dyslexia and dyscalculia, autistic spectrum disorders and so on as well as other applications such as pain management, and the improvement of musical and athletic performance; and (6) Neurofeedback softwares. To date, many studies have been conducted on the neurofeedback therapy and its effectiveness on the treatment of many diseases. Neurofeedback, like other treatments, has its own pros and cons. Although it is a non-invasive procedure, its validity has been questioned in terms of conclusive scientific evidence. For example, it is expensive, time-consuming and its benefits are not long-lasting. Also, it might take months to show the desired improvements. Nevertheless, neurofeedback is known as a complementary and alternative treatment of many brain dysfunctions. However, current research does not support conclusive results about its efficacy. PMID:27303609

Study the left prefrontal cortex activity of Chinese children with dyslexia in phonological processing by NIRS

NASA Astrophysics Data System (ADS)

Zhang, Zhili; Li, Ting; Zheng, Yi; Luo, Qingming; Song, Ranran; Gong, Hui

2006-02-01

Developmental dyslexia, a kind of prevalent psychological disease, represents that dyslexic children have unexpected difficulties in phonological processing and recognition test of Chinese characters. Some functional imaging technologies, such as fMRI and PET, have been used to study the brain activities of the children with dyslexia whose first language is English. In this paper, a portable, 16-channel, continuous-wave (CW) NIRS instrument was used to monitor the concentration changes of each hemoglobin species when Chinese children did the task of phonological processing and recognition test. The NIRS recorded the hemodynamic changes in the left prefrontal cortex of the children. 20 dyslexia-reading children (10~12 years old) and 20 normal-reading children took part in the phonological processing of Chinese characters including the phonological awareness section and the phonological decoding section. During the phonological awareness section, the changed concentration of deoxy-hemoglobin in dyslexia-reading children were significantly higher (p<0.05) than normal-reading children in the left ventrolateral prefrontal cortex (VLPFC). While in the phonological decoding section, both normal and dyslexic reading children had more activity in the left VLPFC, but only normal-reading children had activity in the left middorsal prefrontal cortex. In conclusion, both dyslexic and normal-reading children have activity in the left prefrontal cortex, but the degree and the areas of the prefrontal cortex activity are different between them when they did phonological processing.

An Indexed Bibliography on Tracking

DTIC Science & Technology

1990-07-01

Fitts, P. M., & Schneider, R. H. (1955). Reproduction of simple movements as a function of factors influencing proprioceptive feedback. Journal Qf...V dysfunction, dysmetric, dyslexia, and dyspraxia. Academic Therapy, 12(1), 5-27. 0314 Franks, I.M. & Wilberg, R.B. (1984). Consistent reproduction ...sensori-motor skills. ErggnQ jQ, 1.(4), 407-415. 0851 Pearson, P. (1982). Effects of post- hypnotic suggestion on the performance of a fine motor skill

Dyslexia susceptibility genes influence brain atrophy in frontotemporal dementia.

PubMed

Paternicó, Donata; Premi, Enrico; Alberici, Antonella; Archetti, Silvana; Bonomi, Elisa; Gualeni, Vera; Gasparotti, Roberto; Padovani, Alessandro; Borroni, Barbara

2015-10-01

In this study, we evaluated whether variations within genes specifically associated with dyslexia, namely KIAA0319, DCDC2, and CNTNAP2, were associated with greater damage of language-related regions in patients with frontotemporal dementia (FTD) and primary progressive aphasia (PPA) in particular. A total of 118 patients with FTD, 84 with the behavioral variant of FTD (bvFTD) and 34 with PPA, underwent neuropsychological examination, genetic analyses, and brain MRI. KIAA0319 rs17243157 G/A, DCDC2 rs793842 A/G, and CNTNAP2 rs17236239 A/G genetic variations were assessed. Patients were grouped according to clinical phenotype and genotype status (GA/AA or GG). Gray matter (GM) and white matter (WM) differences were assessed by voxel-based morphometry and structural intercorrelation pattern analyses. Patients carrying KIAA0319 A* (GA or AA) showed greater GM and WM atrophy in the left middle and inferior temporal gyri, as compared with KIAA0319 GG (p < 0.001). The effect of KIAA0319 polymorphism was mainly reported in patients with PPA. In patients with PPA carrying at-risk polymorphism, temporal damage led to loss of interhemispheric and intrahemispheric GM and WM structural association. No effect of DCDC2 and CNTNAP2 was found. Genes involved in dyslexia susceptibility, such as KIAA0319, result in language network vulnerability in FTD, and in PPA in particular.

Left neglect dyslexia and the effect of stimulus duration.

PubMed

Arduino, Lisa S; Vallar, Giuseppe; Burani, Cristina

2006-01-01

The present study investigated the effects of the duration of the stimulus on the reading performance of right-brain-damaged patients with left neglect dyslexia. Three Italian patients read aloud words and nonwords, under conditions of unlimited time of stimulus exposure and of timed presentation. In the untimed condition, the majority of the patients' errors involved the left side of the letter string (i.e., neglect dyslexia errors). Conversely, in the timed condition, although the overall level of performance decreased, errors were more evenly distributed across the whole letter string (i.e., visual - nonlateralized - errors). This reduction of neglect errors with a reduced time of presentation of the stimulus may reflect the read out of elements of the letter string from a preserved visual storage component, such as iconic memory. Conversely, a time-unlimited presentation of the stimulus may bring about the rightward bias that characterizes the performance of neglect patients, possibly by a capture of the patients' attention by the final (rightward) letters of the string.

Simulating reading acquisition: The link between reading outcome and multimodal brain signatures of letter-speech sound learning in prereaders.

PubMed

Karipidis, Iliana I; Pleisch, Georgette; Brandeis, Daniel; Roth, Alexander; Röthlisberger, Martina; Schneebeli, Maya; Walitza, Susanne; Brem, Silvia

2018-05-08

During reading acquisition, neural reorganization of the human brain facilitates the integration of letters and speech sounds, which enables successful reading. Neuroimaging and behavioural studies have established that impaired audiovisual integration of letters and speech sounds is a core deficit in individuals with developmental dyslexia. This longitudinal study aimed to identify neural and behavioural markers of audiovisual integration that are related to future reading fluency. We simulated the first step of reading acquisition by performing artificial-letter training with prereading children at risk for dyslexia. Multiple logistic regressions revealed that our training provides new precursors of reading fluency at the beginning of reading acquisition. In addition, an event-related potential around 400 ms and functional magnetic resonance imaging activation patterns in the left planum temporale to audiovisual correspondences improved cross-validated prediction of future poor readers. Finally, an exploratory analysis combining simultaneously acquired electroencephalography and hemodynamic data suggested that modulation of temporoparietal brain regions depended on future reading skills. The multimodal approach demonstrates neural adaptations to audiovisual integration in the developing brain that are related to reading outcome. Despite potential limitations arising from the restricted sample size, our results may have promising implications both for identifying poor-reading children and for monitoring early interventions.

Audio-visual speech perception in adult readers with dyslexia: an fMRI study.

PubMed

Rüsseler, Jascha; Ye, Zheng; Gerth, Ivonne; Szycik, Gregor R; Münte, Thomas F

2018-04-01

Developmental dyslexia is a specific deficit in reading and spelling that often persists into adulthood. In the present study, we used slow event-related fMRI and independent component analysis to identify brain networks involved in perception of audio-visual speech in a group of adult readers with dyslexia (RD) and a group of fluent readers (FR). Participants saw a video of a female speaker saying a disyllabic word. In the congruent condition, audio and video input were identical whereas in the incongruent condition, the two inputs differed. Participants had to respond to occasionally occurring animal names. The independent components analysis (ICA) identified several components that were differently modulated in FR and RD. Two of these components including fusiform gyrus and occipital gyrus showed less activation in RD compared to FR possibly indicating a deficit to extract face information that is needed to integrate auditory and visual information in natural speech perception. A further component centered on the superior temporal sulcus (STS) also exhibited less activation in RD compared to FR. This finding is corroborated in the univariate analysis that shows less activation in STS for RD compared to FR. These findings suggest a general impairment in recruitment of audiovisual processing areas in dyslexia during the perception of natural speech.

The Nootropic Concept and Dyslexia.

ERIC Educational Resources Information Center

Wilsher, Colin R.

1986-01-01

Studies with Nootropic psychoactive drugs (such as Piracetam) suggest that Piracetam lacks significant side effects; promotes memory and learning; and improves the reading ability of dyslexics, possibly by directly affecting the left-brain hemisphere. Results are contrasted with studies showing the lack of effectiveness of intensive teaching.…

Norman Geschwind Lecture: Geschwind's Lesson.

ERIC Educational Resources Information Center

Duane, Drake D.

2002-01-01

This article reviews the contributions of Norman Geschwind on behavioral neurology. It discusses his novel associations between brain function/structure and behavior and findings from a recent study of 200 individuals with developmental disorders that indicate altered neuroanatomy in dyslexia may be accompanied by altered clinical neurophysiology.…

Visual Illusions: An Interesting Tool to Investigate Developmental Dyslexia and Autism Spectrum Disorder

PubMed Central

Gori, Simone; Molteni, Massimo; Facoetti, Andrea

2016-01-01

A visual illusion refers to a percept that is different in some aspect from the physical stimulus. Illusions are a powerful non-invasive tool for understanding the neurobiology of vision, telling us, indirectly, how the brain processes visual stimuli. There are some neurodevelopmental disorders characterized by visual deficits. Surprisingly, just a few studies investigated illusory perception in clinical populations. Our aim is to review the literature supporting a possible role for visual illusions in helping us understand the visual deficits in developmental dyslexia and autism spectrum disorder. Future studies could develop new tools – based on visual illusions – to identify an early risk for neurodevelopmental disorders. PMID:27199702

The functional anatomy of single-digit arithmetic in children with developmental dyslexia.

PubMed

Evans, Tanya M; Flowers, D Lynn; Napoliello, Eileen M; Olulade, Olumide A; Eden, Guinevere F

2014-11-01

Some arithmetic procedures, such as addition of small numbers, rely on fact retrieval mechanisms supported by left hemisphere perisylvian language areas, while others, such as subtraction, rely on procedural-based mechanisms subserved by bilateral parietal cortices. Previous work suggests that developmental dyslexia, a reading disability, is accompanied by subtle deficits in retrieval-based arithmetic, possibly because of compromised left hemisphere function. To test this prediction, we compared brain activity underlying arithmetic problem solving in children with and without dyslexia during addition and subtraction operations using a factorial design. The main effect of arithmetic operation (addition versus subtraction) for both groups combined revealed activity during addition in the left superior temporal gyrus and activity during subtraction in the bilateral intraparietal sulcus, the right supramarginal gyrus and the anterior cingulate, consistent with prior studies. For the main effect of diagnostic group (dyslexics versus controls), we found less activity in dyslexic children in the left supramarginal gyrus. Finally, the interaction analysis revealed that while the control group showed a strong response in the right supramarginal gyrus for subtraction but not for addition, the dyslexic group engaged this region for both operations. This provides physiological evidence in support of the theory that children with dyslexia, because of disruption to left hemisphere language areas, use a less optimal route for retrieval-based arithmetic, engaging right hemisphere parietal regions typically used by good readers for procedural-based arithmetic. Our results highlight the importance of language processing for mathematical processing and illustrate that children with dyslexia have impairments that extend beyond reading. Copyright © 2014 Elsevier Inc. All rights reserved.

Dyslexic Children Show Atypical Cerebellar Activation and Cerebro-Cerebellar Functional Connectivity in Orthographic and Phonological Processing.

PubMed

Feng, Xiaoxia; Li, Le; Zhang, Manli; Yang, Xiujie; Tian, Mengyu; Xie, Weiyi; Lu, Yao; Liu, Li; Bélanger, Nathalie N; Meng, Xiangzhi; Ding, Guosheng

2017-04-01

Previous neuroimaging studies have found atypical cerebellar activation in individuals with dyslexia in either motor-related tasks or language tasks. However, studies investigating atypical cerebellar activation in individuals with dyslexia have mostly used tasks tapping phonological processing. A question that is yet unanswered is whether the cerebellum in individuals with dyslexia functions properly during orthographic processing of words, as growing evidence shows that the cerebellum is also involved in visual and spatial processing. Here, we investigated cerebellar activation and cerebro-cerebellar functional connectivity during word processing in dyslexic readers and typically developing readers using tasks that tap orthographic and phonological codes. In children with dyslexia, we observed an abnormally higher engagement of the bilateral cerebellum for the orthographic task, which was negatively correlated with literacy measures. The greater the reading impairment was for young dyslexic readers, the stronger the cerebellar activation was. This suggests a compensatory role of the cerebellum in reading for children with dyslexia. In addition, a tendency for higher cerebellar activation in dyslexic readers was found in the phonological task. Moreover, the functional connectivity was stronger for dyslexic readers relative to typically developing readers between the lobule VI of the right cerebellum and the left fusiform gyrus during the orthographic task and between the lobule VI of the left cerebellum and the left supramarginal gyrus during the phonological task. This pattern of results suggests that the cerebellum compensates for reading impairment through the connections with specific brain regions responsible for the ongoing reading task. These findings enhance our understanding of the cerebellum's involvement in reading and reading impairment.

The Functional Anatomy of Single-Digit Arithmetic in Children with Developmental Dyslexia

PubMed Central

Evans, Tanya M.; Flowers, D. Lynn; Napoliello, Eileen M.; Olulade, Olumide A.; Eden, Guinevere F.

2014-01-01

Some arithmetic procedures, such as addition of small numbers, rely on fact retrieval mechanisms supported by left hemisphere perisylvian language areas, while others, such as subtraction, rely on procedural-based mechanisms subserved by bilateral parietal cortices. Previous work suggests that developmental dyslexia, a reading disability, is accompanied by subtle deficits in retrieval-based arithmetic, possibly because of compromised left hemisphere function. To test this prediction, we compared brain activity underlying arithmetic problem solving in children with and without dyslexia during addition and subtraction operations using a factorial design. The main effect of arithmetic operation (addition versus subtraction) for both groups combined revealed activity during addition in the left superior temporal gyrus and activity during subtraction in bilateral intraparietal sulcus, right supramarginal gyrus and the anterior cingulate, consistent with prior studies. For the main effect of diagnostic group (dyslexics versus controls), we found less activity in dyslexic children in the left supramarginal gyrus. Finally, the interaction analysis revealed that while the control group showed a strong response in right supramarginal gyrus for subtraction but not for addition, the dyslexic group engaged this region for both operations. This provides physiological evidence in support of the theory that children with dyslexia, because of disruption to left hemisphere language areas, use a less optimal route for retrieval-based arithmetic, engaging right hemisphere parietal regions typically used by good readers for procedural-based arithmetic. Our results highlight the importance of language processing for mathematical processing and illustrate that children with dyslexia have impairments that extend beyond reading. PMID:25067820

Neuropsychological Features of Dyslexia.

ERIC Educational Resources Information Center

Feifer, Steven G.

This literature review provides support for the idea that subtle anatomical and functional deviations in the brain correlate with specific types of reading disorders. It finds evidence that symmetry or reversed asymmetry in the plana temporale may be associated with difficulty in acquiring sound/symbol relationships. Studies are reported to show…

Diagnosing Dyslexia: The Screening of Auditory Laterality.

ERIC Educational Resources Information Center

Johansen, Kjeld

A study investigated whether a correlation exists between the degree and nature of left-brain laterality and specific reading and spelling difficulties. Subjects, 50 normal readers and 50 reading disabled persons native to the island of Bornholm, had their auditory laterality screened using pure-tone audiometry and dichotic listening. Results…

Minding the Brain

ERIC Educational Resources Information Center

Hruby, George G.

2011-01-01

In literacy education, neuroscience research has been alluded to increasingly in work meant to substantiate cognitive models of the reading process related to text decoding and its instruction. As a result, this material tends to focus on early reading or reading disability and dyslexia (e.g., Hudson, High, & Al Otaiba, 2007; Shaywitz, 2003). It…

Hearing: An Overlooked Fact in Relationship to Dyslexia.

ERIC Educational Resources Information Center

Johansen, Kjeld

Sophisticated neurological research shows that early problems with auditory perception can result in long-range negative effects for the linguistic processes in general, and such long-range effects must be assumed to be correlated with induced degenerative changes in the auditory system and perhaps in the brain's linguistic sector. This research…

Dissociations between developmental dyslexias and attention deficits

PubMed Central

Lukov, Limor; Friedmann, Naama; Shalev, Lilach; Khentov-Kraus, Lilach; Shalev, Nir; Lorber, Rakefet; Guggenheim, Revital

2014-01-01

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 visuospatial attention deficits do not underlie these dyslexias. PMID:25628578

Dissociations between developmental dyslexias and attention deficits.

PubMed

Lukov, Limor; Friedmann, Naama; Shalev, Lilach; Khentov-Kraus, Lilach; Shalev, Nir; Lorber, Rakefet; Guggenheim, Revital

2014-01-01

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 visuospatial attention deficits do not underlie these dyslexias.

The level of audiovisual print-speech integration deficits in dyslexia.

PubMed

Kronschnabel, Jens; Brem, Silvia; Maurer, Urs; Brandeis, Daniel

2014-09-01

The classical phonological deficit account of dyslexia is increasingly linked to impairments in grapho-phonological conversion, and to dysfunctions in superior temporal regions associated with audiovisual integration. The present study investigates mechanisms of audiovisual integration in typical and impaired readers at the critical developmental stage of adolescence. Congruent and incongruent audiovisual as well as unimodal (visual only and auditory only) material was presented. Audiovisual presentations were single letters and three-letter (consonant-vowel-consonant) stimuli accompanied by matching or mismatching speech sounds. Three-letter stimuli exhibited fast phonetic transitions as in real-life language processing and reading. Congruency effects, i.e. different brain responses to congruent and incongruent stimuli were taken as an indicator of audiovisual integration at a phonetic level (grapho-phonological conversion). Comparisons of unimodal and audiovisual stimuli revealed basic, more sensory aspects of audiovisual integration. By means of these two criteria of audiovisual integration, the generalizability of audiovisual deficits in dyslexia was tested. Moreover, it was expected that the more naturalistic three-letter stimuli are superior to single letters in revealing group differences. Electrophysiological and hemodynamic (EEG and fMRI) data were acquired simultaneously in a simple target detection task. Applying the same statistical models to event-related EEG potentials and fMRI responses allowed comparing the effects detected by the two techniques at a descriptive level. Group differences in congruency effects (congruent against incongruent) were observed in regions involved in grapho-phonological processing, including the left inferior frontal and angular gyri and the inferotemporal cortex. Importantly, such differences also emerged in superior temporal key regions. Three-letter stimuli revealed stronger group differences than single letters. No significant differences in basic measures of audiovisual integration emerged. Convergence of hemodynamic and electrophysiological signals appeared to be limited and mainly occurred for highly significant and large effects in visual cortices. The findings suggest efficient superior temporal tuning to audiovisual congruency in controls. In impaired readers, however, grapho-phonological conversion is effortful and inefficient, although basic audiovisual mechanisms seem intact. This unprecedented demonstration of audiovisual deficits in adolescent dyslexics provides critical evidence that the phonological deficit might be explained by impaired audiovisual integration at a phonetic level, especially for naturalistic and word-like stimulation. Copyright © 2014 Elsevier Ltd. All rights reserved.

A structural–functional basis for dyslexia in the cortex of Chinese readers

PubMed Central

Siok, Wai Ting; Niu, Zhendong; Jin, Zhen; Perfetti, Charles A.; Tan, Li Hai

2008-01-01

Developmental dyslexia is a neurobiologically based disorder that affects ≈5–17% of school children and is characterized by a severe impairment in reading skill acquisition. For readers of alphabetic (e.g., English) languages, recent neuroimaging studies have demonstrated that dyslexia is associated with weak reading-related activity in left temporoparietal and occipitotemporal regions, and this activity difference may reflect reductions in gray matter volume in these areas. Here, we find different structural and functional abnormalities in dyslexic readers of Chinese, a nonalphabetic language. Compared with normally developing controls, children with impaired reading in logographic Chinese exhibited reduced gray matter volume in a left middle frontal gyrus region previously shown to be important for Chinese reading and writing. Using functional MRI to study language-related activation of cortical regions in dyslexics, we found reduced activation in this same left middle frontal gyrus region in Chinese dyslexics versus controls, and there was a significant correlation between gray matter volume and activation in the language task in this same area. By contrast, Chinese dyslexics did not show functional or structural (i.e., volumetric gray matter) differences from normal subjects in the more posterior brain systems that have been shown to be abnormal in alphabetic-language dyslexics. The results suggest that the structural and functional basis for dyslexia varies between alphabetic and nonalphabetic languages. PMID:18391194

Impairments of Multisensory Integration and Cross-Sensory Learning as Pathways to Dyslexia

PubMed Central

Hahn, Noemi; Foxe, John J.; Molholm, Sophie

2014-01-01

Two sensory systems are intrinsic to learning to read. Written words enter the brain through the visual system and associated sounds through the auditory system. The task before the beginning reader is quite basic. She must learn correspondences between orthographic tokens and phonemic utterances, and she must do this to the point that there is seamless automatic ‘connection’ between these sensorially distinct units of language. It is self-evident then that learning to read requires formation of cross-sensory associations to the point that deeply encoded multisensory representations are attained. While the majority of individuals manage this task to a high degree of expertise, some struggle to attain even rudimentary capabilities. Why do dyslexic individuals, who learn well in myriad other domains, fail at this particular task? Here, we examine the literature as it pertains to multisensory processing in dyslexia. We find substantial support for multisensory deficits in dyslexia, and make the case that to fully understand its neurological basis, it will be necessary to thoroughly probe the integrity of auditory-visual integration mechanisms. PMID:25265514

Representational neglect for words as revealed by bisection tasks.

PubMed

Arduino, Lisa S; Marinelli, Chiara Valeria; Pasotti, Fabrizio; Ferrè, Elisa Raffaella; Bottini, Gabriella

2012-03-01

In the present study, we showed that a representational disorder for words can dissociate from both representational neglect for objects and neglect dyslexia. This study involved 14 brain-damaged patients with left unilateral spatial neglect and a group of normal subjects. Patients were divided into four groups based on presence of left neglect dyslexia and representational neglect for non-verbal material, as evaluated by the Clock Drawing test. The patients were presented with bisection tasks for words and lines. The word bisection tasks (with words of five and seven letters) comprised the following: (1) representational bisection: the experimenter pronounced a word and then asked the patient to name the letter in the middle position; (2) visual bisection: same as (1) with stimuli presented visually; and (3) motor bisection: the patient was asked to cross out the letter in the middle position. The standard line bisection task was presented using lines of different length. Consistent with the literature, long lines were bisected to the right and short lines, rendered comparable in length to the words of the word bisection test, deviated to the left (crossover effect). Both patients and controls showed the same leftward bias on words in the visual and motor bisection conditions. A significant difference emerged between the groups only in the case of the representational bisection task, whereas the group exhibiting neglect dyslexia associated with representational neglect for objects showed a significant rightward bias, while the other three patient groups and the controls showed a leftward bisection bias. Neither the presence of neglect alone nor the presence of visual neglect dyslexia was sufficient to produce a specific disorder in mental imagery. These results demonstrate a specific representational neglect for words independent of both representational neglect and neglect dyslexia. ©2011 The British Psychological Society.

The role of the left anterior temporal lobe in exception word reading: reconciling patient and neuroimaging findings.

PubMed

Wilson, Maximiliano A; Joubert, Sven; Ferré, Perrine; Belleville, Sylvie; Ansaldo, Ana Inés; Joanette, Yves; Rouleau, Isabelle; Brambati, Simona Maria

2012-05-01

Semantic dementia (SD) is a neurodegenerative disease that occurs following the atrophy of the anterior temporal lobes (ATLs). It is characterised by the degradation of semantic knowledge and difficulties in reading exception words (surface dyslexia). This disease has highlighted the role of the ATLs in the process of exception word reading. However, imaging studies in healthy subjects have failed to detect activation of the ATLs during exception word reading. The aim of the present study was to test whether the functional brain regions that mediate exception word reading in normal readers overlap those brain regions atrophied in SD. In Study One, we map the brain regions of grey matter atrophy in AF, a patient with mild SD and surface dyslexia profile. In Study Two, we map the activation pattern associated with exception word compared to pseudoword reading in young, healthy participants using fMRI. The results revealed areas of significant activation in healthy subjects engaged in the exception word reading task in the left anterior middle temporal gyrus, in a region observed to be atrophic in the patient AF. These results reconcile neuropsychological and functional imaging data, revealing the critical role of the left ATL in exception word reading. Copyright © 2012 Elsevier Inc. All rights reserved.

Facial Speech Gestures: The Relation between Visual Speech Processing, Phonological Awareness, and Developmental Dyslexia in 10-Year-Olds

ERIC Educational Resources Information Center

Schaadt, Gesa; Männel, Claudia; van der Meer, Elke; Pannekamp, Ann; Friederici, Angela D.

2016-01-01

Successful communication in everyday life crucially involves the processing of auditory and visual components of speech. Viewing our interlocutor and processing visual components of speech facilitates speech processing by triggering auditory processing. Auditory phoneme processing, analyzed by event-related brain potentials (ERP), has been shown…

Cortical Reorganization in Dyslexic Children after Phonological Training: Evidence from Early Evoked Potentials

ERIC Educational Resources Information Center

Spironelli, Chiara; Penolazzi, Barbara; Vio, Claudio; Angrilli, Alessandro

2010-01-01

Brain plasticity was investigated in 14 Italian children affected by developmental dyslexia after 6 months of phonological training. The means used to measure language reorganization was the recognition potential, an early wave, also called N150, elicited by automatic word recognition. This component peaks over the left temporo-occipital cortex…

Reproducibility of proton MR spectroscopic imaging (PEPSI): comparison of dyslexic and normal-reading children and effects of treatment on brain lactate levels during language tasks.

PubMed

Richards, Todd L; Berninger, Virginia W; Aylward, Elizabeth H; Richards, Anne L; Thomson, Jennifer B; Nagy, William E; Carlisle, Joanne F; Dager, Stephen R; Abbott, Robert D

2002-01-01

We repeated a proton echo-planar spectroscopic imaging (PEPSI) study to test the hypothesis that children with dyslexia and good readers differ in brain lactate activation during a phonologic judgment task before but not after instructional treatment. We measured PEPSI brain lactate activation (TR/TE, 4000/144; 1.5 T) at two points 1-2 months apart during two language tasks (phonologic and lexical) and a control task (passive listening). Dyslexic participants (n = 10) and control participants (n = 8) (boys and girls aged 9-12 years) were matched in age, verbal intelligence quotients, and valid PEPSI voxels. In contrast to patients in past studies who received combined treatment, our patients were randomly assigned to either phonologic or morphologic (meaning-based) intervention between the scanning sessions. Before treatment, the patients showed significantly greater lactate elevation in the left frontal regions (including the inferior frontal gyrus) during the phonologic task. Both patients and control subjects differed significantly in the right parietal and occipital regions during both tasks. After treatment, the two groups did not significantly differ in any brain region during either task, but individuals given morphologic treatment were significantly more likely to have reduced left frontal lactate activation during the phonologic task. The previous finding of greater left frontal lactate elevation in children with dyslexia during a phonologic judgment task was replicated, and brain activation changed as a result of treatment. However, the treatment effect was due to the morphologic component rather than the phonologic component.

Multi-parameter machine learning approach to the neuroanatomical basis of developmental dyslexia.

PubMed

Płoński, Piotr; Gradkowski, Wojciech; Altarelli, Irene; Monzalvo, Karla; van Ermingen-Marbach, Muna; Grande, Marion; Heim, Stefan; Marchewka, Artur; Bogorodzki, Piotr; Ramus, Franck; Jednoróg, Katarzyna

2017-02-01

Despite decades of research, the anatomical abnormalities associated with developmental dyslexia are still not fully described. Studies have focused on between-group comparisons in which different neuroanatomical measures were generally explored in isolation, disregarding potential interactions between regions and measures. Here, for the first time a multivariate classification approach was used to investigate grey matter disruptions in children with dyslexia in a large (N = 236) multisite sample. A variety of cortical morphological features, including volumetric (volume, thickness and area) and geometric (folding index and mean curvature) measures were taken into account and generalizability of classification was assessed with both 10-fold and leave-one-out cross validation (LOOCV) techniques. Classification into control vs. dyslexic subjects achieved above chance accuracy (AUC = 0.66 and ACC = 0.65 in the case of 10-fold CV, and AUC = 0.65 and ACC = 0.64 using LOOCV) after principled feature selection. Features that discriminated between dyslexic and control children were exclusively situated in the left hemisphere including superior and middle temporal gyri, subparietal sulcus and prefrontal areas. They were related to geometric properties of the cortex, with generally higher mean curvature and a greater folding index characterizing the dyslexic group. Our results support the hypothesis that an atypical curvature pattern with extra folds in left hemispheric perisylvian regions characterizes dyslexia. Hum Brain Mapp 38:900-908, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

How Should Medical Schools Respond to Students with Dyslexia?

PubMed

Romberg, Frederick; Shaywitz, Bennett A; Shaywitz, Sally E

2016-10-01

We examine the dilemmas faced by a medical student with dyslexia who wonders whether he should "out" himself to faculty to receive the accommodations entitled by federal law. We first discuss scientific evidence on dyslexia's prevalence, unexpected nature, and neurobiology. We then examine the experiences of medical students who have revealed their dyslexia to illustrate the point that, far too often, attending physicians who know little about dyslexia can misperceive the motives or behavior of students with dyslexia. Because ignorance and misperception of dyslexia can result in bias against students with dyslexia, we strongly recommend a mandatory course for faculty that provides a basic scientific and clinical overview of dyslexia to facilitate greater understanding of dyslexia and support for students with dyslexia. © 2016 American Medical Association. All Rights Reserved.

Reading Impairment in a Patient with Missing Arcuate Fasciculus

ERIC Educational Resources Information Center

Rauschecker, Andreas M.; Deutsch, Gayle K.; Ben-Shachar, Michal; Schwartzman, Armin; Perry, Lee M.; Dougherty, Robert F.

2009-01-01

We describe the case of a child ("S") who was treated with radiation therapy at age 5 for a recurrent malignant brain tumor. Radiation successfully abolished the tumor but caused radiation-induced tissue necrosis, primarily affecting cerebral white matter. "S" was introduced to us at age 15 because of her profound dyslexia. We assessed cognitive…

Reading, Laterality, and the Brain: Early Contributions on Reading Disabilities by Sara S. Sparrow

ERIC Educational Resources Information Center

Fletcher, Jack M.; Morris, Robin D.

2014-01-01

Although best known for work with children and adults with intellectual disabilities and autism spectrum disorders, training in speech pathology and a doctorate in clinical psychology and neuropsychology was the foundation for Sara Sparrow's long-term interest in reading disabilities. Her first papers were on dyslexia and laterality, and the…

Procedural learning and dyslexia.

PubMed

Nicolson, R I; Fawcett, A J; Brookes, R L; Needle, J

2010-08-01

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. 2010 John Wiley & Sons, Ltd.

Blood-brain barrier dysfunction in brain diseases: clinical experience.

PubMed

Schoknecht, Karl; Shalev, Hadar

2012-11-01

The blood-brain barrier, a unique feature of the cerebral vasculature, is gaining attention as a feature in common neurologic disorders including stroke, traumatic brain injury, epilepsy, and schizophrenia. Although acute blood-brain barrier dysfunction can induce cerebral edema, seizures, or neuropsychiatric symptoms, epileptogenesis and cognitive decline are among the chronic effects. The mechanisms underlying blood-brain barrier dysfunction are diverse and may range from physical endothelial damage in traumatic brain injury to degradation of extracellular matrix proteins via matrix metalloproteinases as part of an inflammatory response. Clinically, blood-brain barrier dysfunction is often detected using contrast-enhanced imaging. However, these techniques do not give any insights into the underlying mechanism. Elucidating the specific pathways of blood-brain barrier dysfunction at different time points and in different brain diseases using novel imaging techniques promises a more accurate blood-brain barrier terminology as well as new treatment options and personalized treatment. Wiley Periodicals, Inc. © 2012 International League Against Epilepsy.

Too little or too much? Parafoveal preview benefits and parafoveal load costs in dyslexic adults.

PubMed

Silva, Susana; Faísca, Luís; Araújo, Susana; Casaca, Luis; Carvalho, Loide; Petersson, Karl Magnus; Reis, Alexandra

2016-07-01

Two different forms of parafoveal dysfunction have been hypothesized as core deficits of dyslexic individuals: reduced parafoveal preview benefits ("too little parafovea") and increased costs of parafoveal load ("too much parafovea"). We tested both hypotheses in a single eye-tracking experiment using a modified serial rapid automatized naming (RAN) task. Comparisons between dyslexic and non-dyslexic adults showed reduced parafoveal preview benefits in dyslexics, without increased costs of parafoveal load. Reduced parafoveal preview benefits were observed in a naming task, but not in a silent letter-finding task, indicating that the parafoveal dysfunction may be consequent to the overload with extracting phonological information from orthographic input. Our results suggest that dyslexics' parafoveal dysfunction is not based on strict visuo-attentional factors, but nevertheless they stress the importance of extra-phonological processing. Furthermore, evidence of reduced parafoveal preview benefits in dyslexia may help understand why serial RAN is an important reading predictor in adulthood.

Neural initialization of audiovisual integration in prereaders at varying risk for developmental dyslexia.

PubMed

I Karipidis, Iliana; Pleisch, Georgette; Röthlisberger, Martina; Hofstetter, Christoph; Dornbierer, Dario; Stämpfli, Philipp; Brem, Silvia

2017-02-01

Learning letter-speech sound correspondences is a major step in reading acquisition and is severely impaired in children with dyslexia. Up to now, it remains largely unknown how quickly neural networks adopt specific functions during audiovisual integration of linguistic information when prereading children learn letter-speech sound correspondences. Here, we simulated the process of learning letter-speech sound correspondences in 20 prereading children (6.13-7.17 years) at varying risk for dyslexia by training artificial letter-speech sound correspondences within a single experimental session. Subsequently, we acquired simultaneously event-related potentials (ERP) and functional magnetic resonance imaging (fMRI) scans during implicit audiovisual presentation of trained and untrained pairs. Audiovisual integration of trained pairs correlated with individual learning rates in right superior temporal, left inferior temporal, and bilateral parietal areas and with phonological awareness in left temporal areas. In correspondence, a differential left-lateralized parietooccipitotemporal ERP at 400 ms for trained pairs correlated with learning achievement and familial risk. Finally, a late (650 ms) posterior negativity indicating audiovisual congruency of trained pairs was associated with increased fMRI activation in the left occipital cortex. Taken together, a short (<30 min) letter-speech sound training initializes audiovisual integration in neural systems that are responsible for processing linguistic information in proficient readers. To conclude, the ability to learn grapheme-phoneme correspondences, the familial history of reading disability, and phonological awareness of prereading children account for the degree of audiovisual integration in a distributed brain network. Such findings on emerging linguistic audiovisual integration could allow for distinguishing between children with typical and atypical reading development. Hum Brain Mapp 38:1038-1055, 2017. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Assessment of rhythmic entrainment at multiple timescales in dyslexia: Evidence for disruption to syllable timing☆

PubMed Central

Leong, Victoria; Goswami, Usha

2014-01-01

Developmental dyslexia is associated with rhythmic difficulties, including impaired perception of beat patterns in music and prosodic stress patterns in speech. Spoken prosodic rhythm is cued by slow (<10 Hz) fluctuations in speech signal amplitude. Impaired neural oscillatory tracking of these slow amplitude modulation (AM) patterns is one plausible source of impaired rhythm tracking in dyslexia. Here, we characterise the temporal profile of the dyslexic rhythm deficit by examining rhythmic entrainment at multiple speech timescales. Adult dyslexic participants completed two experiments aimed at testing the perception and production of speech rhythm. In the perception task, participants tapped along to the beat of 4 metrically-regular nursery rhyme sentences. In the production task, participants produced the same 4 sentences in time to a metronome beat. Rhythmic entrainment was assessed using both traditional rhythmic indices and a novel AM-based measure, which utilised 3 dominant AM timescales in the speech signal each associated with a different phonological grain-sized unit (0.9–2.5 Hz, prosodic stress; 2.5–12 Hz, syllables; 12–40 Hz, phonemes). The AM-based measure revealed atypical rhythmic entrainment by dyslexic participants to syllable patterns in speech, in perception and production. In the perception task, both groups showed equally strong phase-locking to Syllable AM patterns, but dyslexic responses were entrained to a significantly earlier oscillatory phase angle than controls. In the production task, dyslexic utterances showed shorter syllable intervals, and differences in Syllable:Phoneme AM cross-frequency synchronisation. Our data support the view that rhythmic entrainment at slow (∼5 Hz, Syllable) rates is atypical in dyslexia, suggesting that neural mechanisms for syllable perception and production may also be atypical. These syllable timing deficits could contribute to the atypical development of phonological representations for spoken words, the central cognitive characteristic of developmental dyslexia across languages. This article is part of a Special Issue entitled . PMID:23916752

Dyslexia Defined. NetNews. Volume 5, Number 2

ERIC Educational Resources Information Center

LDA of Minnesota, 2004

2004-01-01

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?…

Left-right asymmetry of the Maxwell spot centroids in adults without and with dyslexia.

PubMed

Le Floch, Albert; Ropars, Guy

2017-10-25

In human vision, the brain has to select one view of the world from our two eyes. However, the existence of a clear anatomical asymmetry providing an initial imbalance for normal neural development is still not understood. Using a so-called foveascope, we found that for a cohort of 30 normal adults, the two blue cone-free areas at the centre of the foveas are asymmetrical. The noise-stimulated afterimage dominant eye introduced here corresponds to the circular blue cone-free area, while the non-dominant eye corresponds to the diffuse and irregular elliptical outline. By contrast, we found that this asymmetry is absent or frustrated in a similar cohort of 30 adults with normal ocular status, but with dyslexia, i.e. with visual and phonological deficits. In this case, our results show that the two Maxwell centroid outlines are both circular but lead to an undetermined afterimage dominance with a coexistence of primary and mirror images. The interplay between the lack of asymmetry and the development in the neural maturation of the brain pathways suggests new implications in both fundamental and biomedical sciences. © 2017 The Author(s).

Psychosocial Functioning of Children with and without Dyslexia: A Follow-up Study from Ages Four to Nine.

PubMed

Parhiala, P; Torppa, M; Eklund, K; Aro, T; Poikkeus, A-M; Heikkilä, R; Ahonen, T

2015-08-01

This longitudinal study compares developmental changes in psychosocial functioning during the transition into school of children with and without dyslexia. In addition, it examines the effects of gender and family risk for dyslexia in terms of the associations between dyslexia and psychosocial functioning. Children's psychosocial functioning (social skills, inattention and externalizing and internalizing problems) was evaluated by their parents at ages 4, 6 and 9, and diagnosis for dyslexia was made at age 8 (in grade 2). The findings indicated that children with dyslexia were already rated as having poorer social skills and being more inattentive than were typical readers before their entry into school. Significant interactions of gender and diagnosis of dyslexia emerged for social skills and inattention. The social skills of boys with dyslexia improved after school entry as compared to the level of girls without dyslexia, whereas the social skills of girls with dyslexia did not improve. Boys with dyslexia were rated as showing a high level of inattention both prior to and after school entry, whereas, for girls with dyslexia, inattention ratings increased after school entry, eventually matching the boys' levels. Copyright © 2014 John Wiley & Sons, Ltd.

Learning problems, delayed development, and puberty

PubMed Central

Wright, Beverly A.; Zecker, Steven G.

2004-01-01

Language-based learning disorders such as dyslexia affect millions of people, but there is little agreement as to their cause. New evidence from behavioral measures of the ability to hear tones in the presence of background noise indicates that the brains of affected individuals develop more slowly than those of their unaffected counterparts. In addition, it seems that brain changes occurring at ≈10 years of age, presumably associated with puberty, may prematurely halt this slower-than-normal development when improvements would normally continue into adolescence. The combination of these ideas can account for a wide range of previous results, suggesting that delayed brain development, and its interaction with puberty, may be key factors contributing to learning problems. PMID:15210987

Dyslexia and Astronomy

NASA Astrophysics Data System (ADS)

Schneps, Matthew H.; Greenhill, L. J.; Rose, L. T.

2007-12-01

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.

Dorsal brain stem syndrome: MR imaging location of brain stem tegmental lesions in neonates with oral motor dysfunction.

PubMed

Quattrocchi, C C; Longo, D; Delfino, L N; Cilio, M R; Piersigilli, F; Capua, M D; Seganti, G; Danhaive, O; Fariello, G

2010-09-01

The anatomic extent of brain stem damage may provide information about clinical outcome and prognosis in children with hypoxic-ischemic encephalopathy and oral motor dysfunction. The aim of this study was to retrospectively characterize the location and extent of brain stem lesions in children with oral motor dysfunction. From January 2005 to August 2009, 43 infants hospitalized at our institution were included in the study because of a history of hypoxic-ischemic events. Of this group, 14 patients showed oral motor dysfunction and brain stem tegmental lesions detected at MR imaging. MR imaging showed hypoxic-ischemic lesions in supra- and infratentorial areas. Six of 14 patients revealed only infratentorial lesions. Focal symmetric lesions of the tegmental brain stem were always present. The lesions appeared hyperintense on T2-weighted images and hypointense on IR images. We found a strong association (P < .0001) between oral motor dysfunction and infratentorial lesions on MR imaging. Oral motor dysfunction was associated with brain stem tegmental lesions in posthypoxic-ischemic infants. The MR imaging examination should be directed to the brain stem, especially when a condition of prolonged gavage feeding is necessary in infants.

Arithmetic Skills in Using Algorithms

DTIC Science & Technology

1990-06-01

that this bulb is really defective? (table continues) 3 Table 1 (continued) Dyslexia Dyslexia is a disorder characterized by an impaired ability to...read. Two percent (2%) of all first graders have dyslexia . A screen4ng test for dyslexia has recently been devised that can be used with first graders...whether the child has dyslexia . The screening test is not completely accurate. For children who really have dyslexia , the screening test is positive

Why Autism Must Be Taken Apart

ERIC Educational Resources Information Center

Waterhouse, Lynn; Gillberg, Christopher

2014-01-01

Although accumulated evidence has demonstrated that autism is found with many varied brain dysfunctions, researchers have tried to find a single brain dysfunction that would provide neurobiological validity for autism. However, unitary models of autism brain dysfunction have not adequately addressed conflicting evidence, and efforts to find a…

An eye movement based reading intervention in lexical and segmental readers with acquired dyslexia.

PubMed

Ablinger, Irene; von Heyden, Kerstin; Vorstius, Christian; Halm, Katja; Huber, Walter; Radach, Ralph

2014-01-01

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.

Lack of replication for the myosin-18B association with mathematical ability in independent cohorts.

PubMed

Pettigrew, K A; Fajutrao Valles, S F; Moll, K; Northstone, K; Ring, S; Pennell, C; Wang, C; Leavett, R; Hayiou-Thomas, M E; Thompson, P; Simpson, N H; Fisher, S E; Whitehouse, A J O; Snowling, M J; Newbury, D F; Paracchini, S

2015-04-01

Twin studies indicate that dyscalculia (or mathematical disability) is caused partly by a genetic component, which is yet to be understood at the molecular level. Recently, a coding variant (rs133885) in the myosin-18B gene was shown to be associated with mathematical abilities with a specific effect among children with dyslexia. This association represents one of the most significant genetic associations reported to date for mathematical abilities and the only one reaching genome-wide statistical significance. We conducted a replication study in different cohorts to assess the effect of rs133885 maths-related measures. The study was conducted primarily using the Avon Longitudinal Study of Parents and Children (ALSPAC), (N = 3819). We tested additional cohorts including the York Cohort, the Specific Language Impairment Consortium (SLIC) cohort and the Raine Cohort, and stratified them for a definition of dyslexia whenever possible. We did not observe any associations between rs133885 in myosin-18B and mathematical abilities among individuals with dyslexia or in the general population. Our results suggest that the myosin-18B variant is unlikely to be a main factor contributing to mathematical abilities. © 2015 The Authors. Genes, Brain and Behavior published by International Behavioural and Neural Genetics Society and John Wiley & Sons Ltd.

Dyslexia: What Teachers Need to Know

ERIC Educational Resources Information Center

Williams, Joan A.; Lynch, Sharon A.

2010-01-01

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…

Dyslexia in higher education: implications for maths anxiety, statistics anxiety and psychological well-being.

PubMed

Jordan, Julie-Ann; McGladdery, Gary; Dyer, Kevin

2014-08-01

This study examined levels of mathematics and statistics anxiety, as well as general mental health amongst undergraduate students with dyslexia (n = 28) and those without dyslexia (n = 71). Students with dyslexia had higher levels of mathematics anxiety relative to those without dyslexia, while statistics anxiety and general mental health were comparable for both reading ability groups. In terms of coping strategies, undergraduates with dyslexia tended to use planning-based strategies and seek instrumental support more frequently than those without dyslexia. Higher mathematics anxiety was associated with having a dyslexia diagnosis, as well as greater levels of worrying, denial, seeking instrumental support and less use of the positive reinterpretation coping strategy. By contrast, statistics anxiety was not predicted by dyslexia diagnosis, but was instead predicted by overall worrying and the use of denial and emotion focused coping strategies. The results suggest that disability practitioners should be aware that university students with dyslexia are at risk of high mathematics anxiety. Additionally, effective anxiety reduction strategies such as positive reframing and thought challenging would form a useful addition to the support package delivered to many students with dyslexia. Copyright © 2014 John Wiley & Sons, Ltd.

Are Specific Language Impairment and Dyslexia Distinct Disorders?

PubMed Central

Catts, Hugh W.; Adlof, Suzanne M.; Hogan, Tiffany; Weismer, Susan Ellis

2010-01-01

Purpose The purpose of this study was to determine whether specific language impairment (SLI) and dyslexia are distinct developmental disorders. Method Study 1 investigated the overlap between SLI identified in kindergarten and dyslexia identified in 2nd, 4th, or 8th grades in a representative sample of 527 children. Study 2 examined phonological processing in a subsample of participants, including 21 children with dyslexia only, 43 children with SLI only, 18 children with SLI and dyslexia, and 165 children with typical language/reading development. Measures of phonological awareness and nonword repetition were considered. Results Study 1 showed limited but statistically significant overlap between SLI and dyslexia. Study 2 found that children with dyslexia or a combination of dyslexia and SLI performed significantly less well on measures of phonological processing than did children with SLI only and those with typical development. Children with SLI only showed only mild deficits in phonological processing compared with typical children. Conclusions These results support the view that SLI and dyslexia are distinct but potentially comorbid developmental language disorders. A deficit in phonological processing is closely associated with dyslexia but not with SLI when it occurs in the absence of dyslexia. PMID:16478378

Fictional Characters with Dyslexia: What Are We Seeing in Books?

ERIC Educational Resources Information Center

Altieri, Jennifer L.

2008-01-01

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…

Depression and Anxiety among Transitioning Adolescents and College Students with ADHD, Dyslexia, or Comorbid ADHD/Dyslexia

ERIC Educational Resources Information Center

Nelson, Jason M.; Gregg, Noel

2012-01-01

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.…

Dyslexia Heterogeneity: Cognitive Profiling of Portuguese Children with Dyslexia

ERIC Educational Resources Information Center

Pacheco, Andreia; Reis, Alexandra; Araújo, Susana; Inácio, Filomena; Petersson, Karl Magnus; Faísca, Luís

2014-01-01

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…

Dispelling the Myth: Training in Education or Neuroscience Decreases but Does Not Eliminate Beliefs in Neuromyths

PubMed Central

Macdonald, Kelly; Germine, Laura; Anderson, Alida; Christodoulou, Joanna; McGrath, Lauren M.

2017-01-01

Neuromyths are misconceptions about brain research and its application to education and learning. Previous research has shown that these myths may be quite pervasive among educators, but less is known about how these rates compare to the general public or to individuals who have more exposure to neuroscience. This study is the first to use a large sample from the United States to compare the prevalence and predictors of neuromyths among educators, the general public, and individuals with high neuroscience exposure. Neuromyth survey responses and demographics were gathered via an online survey hosted at TestMyBrain.org. We compared performance among the three groups of interest: educators (N = 598), high neuroscience exposure (N = 234), and the general public (N = 3,045) and analyzed predictors of individual differences in neuromyths performance. In an exploratory factor analysis, we found that a core group of 7 “classic” neuromyths factored together (items related to learning styles, dyslexia, the Mozart effect, the impact of sugar on attention, right-brain/left-brain learners, and using 10% of the brain). The general public endorsed the greatest number of neuromyths (M = 68%), with significantly fewer endorsed by educators (M = 56%), and still fewer endorsed by the high neuroscience exposure group (M = 46%). The two most commonly endorsed neuromyths across all groups were related to learning styles and dyslexia. More accurate performance on neuromyths was predicted by age (being younger), education (having a graduate degree), exposure to neuroscience courses, and exposure to peer-reviewed science. These findings suggest that training in education and neuroscience can help reduce but does not eliminate belief in neuromyths. We discuss the possible underlying roots of the most prevalent neuromyths and implications for classroom practice. These empirical results can be useful for developing comprehensive training modules for educators that target general misconceptions about the brain and learning. PMID:28848461

Dispelling the Myth: Training in Education or Neuroscience Decreases but Does Not Eliminate Beliefs in Neuromyths.

PubMed

Macdonald, Kelly; Germine, Laura; Anderson, Alida; Christodoulou, Joanna; McGrath, Lauren M

2017-01-01

Neuromyths are misconceptions about brain research and its application to education and learning. Previous research has shown that these myths may be quite pervasive among educators, but less is known about how these rates compare to the general public or to individuals who have more exposure to neuroscience. This study is the first to use a large sample from the United States to compare the prevalence and predictors of neuromyths among educators, the general public, and individuals with high neuroscience exposure. Neuromyth survey responses and demographics were gathered via an online survey hosted at TestMyBrain.org. We compared performance among the three groups of interest: educators ( N = 598), high neuroscience exposure ( N = 234), and the general public ( N = 3,045) and analyzed predictors of individual differences in neuromyths performance. In an exploratory factor analysis, we found that a core group of 7 "classic" neuromyths factored together (items related to learning styles, dyslexia, the Mozart effect, the impact of sugar on attention, right-brain/left-brain learners, and using 10% of the brain). The general public endorsed the greatest number of neuromyths ( M = 68%), with significantly fewer endorsed by educators ( M = 56%), and still fewer endorsed by the high neuroscience exposure group ( M = 46%). The two most commonly endorsed neuromyths across all groups were related to learning styles and dyslexia. More accurate performance on neuromyths was predicted by age (being younger), education (having a graduate degree), exposure to neuroscience courses, and exposure to peer-reviewed science. These findings suggest that training in education and neuroscience can help reduce but does not eliminate belief in neuromyths. We discuss the possible underlying roots of the most prevalent neuromyths and implications for classroom practice. These empirical results can be useful for developing comprehensive training modules for educators that target general misconceptions about the brain and learning.

Neural substrates related to auditory working memory comparisons in dyslexia: An fMRI study

PubMed Central

CONWAY, TIM; HEILMAN, KENNETH M.; GOPINATH, KAUNDINYA; PECK, KYUNG; BAUER, RUSSELL; BRIGGS, RICHARD W.; TORGESEN, JOSEPH K.; CROSSON, BRUCE

2010-01-01

Adult readers with developmental phonological dyslexia exhibit significant difficulty comparing pseudowords and pure tones in auditory working memory (AWM). This suggests deficient AWM skills for adults diagnosed with dyslexia. Despite behavioral differences, it is unknown whether neural substrates of AWM differ between adults diagnosed with dyslexia and normal readers. Prior neuroimaging of adults diagnosed with dyslexia and normal readers, and post-mortem findings of neural structural anomalies in adults diagnosed with dyslexia support the hypothesis of atypical neural activity in temporoparietal and inferior frontal regions during AWM tasks in adults diagnosed with dyslexia. We used fMRI during two binaural AWM tasks (pseudowords or pure tones comparisons) in adults diagnosed with dyslexia (n = 11) and normal readers (n = 11). For both AWM tasks, adults diagnosed with dyslexia exhibited greater activity in left posterior superior temporal (BA 22) and inferior parietal regions (BA 40) than normal readers. Comparing neural activity between groups and between stimuli contrasts (pseudowords vs. tones), adults diagnosed with dyslexia showed greater primary auditory cortex activity (BA 42; tones > pseudowords) than normal readers. Thus, greater activity in primary auditory, posterior superior temporal, and inferior parietal cortices during linguistic and non-linguistic AWM tasks for adults diagnosed with dyslexia compared to normal readers indicate differences in neural substrates of AWM comparison tasks. PMID:18577292

Five Describing Factors of Dyslexia.

PubMed

Tamboer, Peter; Vorst, Harrie C M; Oort, Frans J

2016-09-01

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. © Hammill Institute on Disabilities 2014.

Speech and Language Difficulties in Children with and without a Family History of Dyslexia

ERIC Educational Resources Information Center

Carroll, Julia M.; Myers, Joanne M.

2010-01-01

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…

Predicting Dyslexia at Age 11 from a Risk Index Questionnaire at Age 5

ERIC Educational Resources Information Center

Helland, Turid; Plante, Elena; Hugdahl, Kenneth

2011-01-01

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…

Practitioners' Perceptions of Dyslexia and Approaches towards Teaching Learners with Dyslexia in Adult Literacy Classes

ERIC Educational Resources Information Center

Ade-Ojo, Gordon O.

2012-01-01

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…

Coping Successfully with Dyslexia: An Initial Study of an Inclusive School-Based Resilience Programme

ERIC Educational Resources Information Center

Firth, Nola; Frydenberg, Erica; Steeg, Charlotte; Bond, Lyndal

2013-01-01

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…

Is Weak Oral Language Associated with Poor Spelling in School-Age Children with Specific Language Impairment, Dyslexia, or Both?

PubMed Central

McCarthy, Jillian H.; Hogan, Tiffany P.; Catts, Hugh W.

2013-01-01

The purpose of this study was to test the hypothesis that word reading accuracy, not oral language, is associated with spelling performance in school-age children. We compared fourth grade spelling accuracy in children with specific language impairment (SLI), dyslexia, or both (SLI/dyslexia) to their typically developing grade-matched peers. Results of the study revealed that children with SLI performed similarly to their typically developing peers on a single word spelling task. Alternatively, those with dyslexia and SLI/dyslexia evidenced poor spelling accuracy. Errors made by both those with dyslexia and SLI/dyslexia were characterized by numerous phonologic, orthographic, and semantic errors. Cumulative results support the hypothesis that word reading accuracy, not oral language, is associated with spelling performance in typically developing school-age children and their peers with SLI and dyslexia. Findings are provided as further support for the notion that SLI and dyslexia are distinct, yet co-morbid, developmental disorders. PMID:22876769

Effect of Atomoxetine Treatment on Reading and Phonological Skills in Children with Dyslexia or Attention-Deficit/Hyperactivity Disorder and Comorbid Dyslexia in a Randomized, Placebo-Controlled Trial.

PubMed

Shaywitz, Sally; Shaywitz, Bennett; Wietecha, Linda; Wigal, Sharon; McBurnett, Keith; Williams, David; Kronenberger, William G; Hooper, Stephen R

2017-02-01

Evaluated the effects of atomoxetine on the reading abilities of children with dyslexia only or attention-deficit/hyperactivity disorder (ADHD) and comorbid dyslexia. Children aged 10-16 years (N = 209) met Diagnostic and Statistical Manual of Mental Disorders, 4th Edition, Text Revision (DSM-IV-TR) criteria for dyslexia only (n = 58), ADHD and comorbid dyslexia (n = 124), or ADHD only (n = 27) and were of normal intelligence. Patients were treated with atomoxetine (1.0-1.4 mg/kg/day) or placebo in a 16-week, randomized, placebo-controlled, double-blind trial. The dyslexia-only and ADHD and comorbid dyslexia groups were randomized 1:1; the ADHD-only group received atomoxetine in a blinded manner. Reading abilities were measured with the Woodcock Johnson III (WJIII), Comprehensive Test of Phonological Processing (CTOPP), Gray Oral Reading Tests-4, and Test of Word Reading Efficiency. Atomoxetine-treated dyslexia-only patients compared with placebo patients had significantly greater improvement (p < 0.02) with moderate to approaching high effect sizes (ES) on WJIII Word Attack (ES = 0.72), Basic Reading Skills (ES = 0.48), and Reading Vocabulary (ES = 0.73). In the atomoxetine-treated ADHD and comorbid dyslexia group, improvement on the CTOPP Elision measure (ES = 0.50) was significantly greater compared with placebo (p < 0.02). Total, inattentive, and hyperactive/impulsive ADHD symptom reductions were significant in the atomoxetine-treated ADHD and comorbid dyslexia group compared with placebo, and from baseline in the ADHD-only group (p ≤ 0.02). ADHD symptom improvements in the ADHD and comorbid dyslexia group were not correlated with improvements in reading. Atomoxetine treatment improved reading scores in patients with dyslexia only and ADHD and comorbid dyslexia. Improvements for patients with dyslexia only were in critical components of reading, including decoding and reading vocabulary. For patients with ADHD and comorbid dyslexia, improvements in reading scores were distinct from improvement in ADHD inattention symptoms alone. These data represent the first report of improvements in reading measures following pharmacotherapy treatment in patients with dyslexia only evaluated in a randomized, double-blind trial.

Effect of Atomoxetine Treatment on Reading and Phonological Skills in Children with Dyslexia or Attention-Deficit/Hyperactivity Disorder and Comorbid Dyslexia in a Randomized, Placebo-Controlled Trial

PubMed Central

Shaywitz, Bennett; Wietecha, Linda; Wigal, Sharon; McBurnett, Keith; Williams, David; Kronenberger, William G.; Hooper, Stephen R.

2017-01-01

Abstract Objectives: Evaluated the effects of atomoxetine on the reading abilities of children with dyslexia only or attention-deficit/hyperactivity disorder (ADHD) and comorbid dyslexia. Methods: Children aged 10–16 years (N = 209) met Diagnostic and Statistical Manual of Mental Disorders, 4th Edition, Text Revision (DSM-IV-TR) criteria for dyslexia only (n = 58), ADHD and comorbid dyslexia (n = 124), or ADHD only (n = 27) and were of normal intelligence. Patients were treated with atomoxetine (1.0–1.4 mg/kg/day) or placebo in a 16-week, randomized, placebo-controlled, double-blind trial. The dyslexia-only and ADHD and comorbid dyslexia groups were randomized 1:1; the ADHD-only group received atomoxetine in a blinded manner. Reading abilities were measured with the Woodcock Johnson III (WJIII), Comprehensive Test of Phonological Processing (CTOPP), Gray Oral Reading Tests-4, and Test of Word Reading Efficiency. Results: Atomoxetine-treated dyslexia-only patients compared with placebo patients had significantly greater improvement (p < 0.02) with moderate to approaching high effect sizes (ES) on WJIII Word Attack (ES = 0.72), Basic Reading Skills (ES = 0.48), and Reading Vocabulary (ES = 0.73). In the atomoxetine-treated ADHD and comorbid dyslexia group, improvement on the CTOPP Elision measure (ES = 0.50) was significantly greater compared with placebo (p < 0.02). Total, inattentive, and hyperactive/impulsive ADHD symptom reductions were significant in the atomoxetine-treated ADHD and comorbid dyslexia group compared with placebo, and from baseline in the ADHD-only group (p ≤ 0.02). ADHD symptom improvements in the ADHD and comorbid dyslexia group were not correlated with improvements in reading. Conclusions: Atomoxetine treatment improved reading scores in patients with dyslexia only and ADHD and comorbid dyslexia. Improvements for patients with dyslexia only were in critical components of reading, including decoding and reading vocabulary. For patients with ADHD and comorbid dyslexia, improvements in reading scores were distinct from improvement in ADHD inattention symptoms alone. These data represent the first report of improvements in reading measures following pharmacotherapy treatment in patients with dyslexia only evaluated in a randomized, double-blind trial. PMID:27410907

Clinicians with dyslexia: a systematic review of effects and strategies.

PubMed

Locke, Rachel; Scallan, Samantha; Mann, Richard; Alexander, Gail

2015-12-01

For educators, an awareness of the impact of dyslexia on learners in the clinical workplace is vital: first, to be able to identify whether dyslexia may underlie certain traits and behaviours; and second, to be able to provide appropriate advice and support when dyslexia is identified. We reviewed the primary research evidence concerning the effects of dyslexia on clinicians (in or after training) in the workplace, and adaptive strategies ('workarounds') that are presently in use. A systematic search of literature was undertaken, followed by a narrative review of studies selected as meeting the inclusion criteria. The review used a priori research questions and focused on studies based on primary research evidence. The review identified five key studies on qualified doctors or nurses with dyslexia. The impact of dyslexia on doctors can include: writing and calculating prescriptions, writing patient notes, and prioritising and making referrals. Strategies to minimise the effects of dyslexia include the use of adaptive technologies, the need for more time for mentors and supervisors, and an awareness of 'enabling' and 'disabling' environments. An awareness of the impact of dyslexia on learners in the clinical workplace is vital The difficulties associated with dyslexia are varied and may be unexpected. Medical educators must therefore be aware of dyslexia and its impact. When supporting a trainee with dyslexia, there is guidance available but educators may struggle to identify strategies and resources that are evidence based, so further research is required. © 2015 John Wiley & Sons Ltd.

Emotional experience with dyslexia and self-esteem: the protective role of perceived family support in late adulthood.

PubMed

Carawan, Lena W; Nalavany, Blace A; Jenkins, Carol

2016-01-01

Despite the growing body of evidence that suggests dyslexia persists through the life span, there is a dearth of research that explores the complicating factor of dyslexia in late adulthood. Based upon stress and coping theory, this study examined whether perceived family support protects the impact of negative emotional experience with dyslexia on self-esteem. Adults aged 21 years and older with diagnosed or self-reported dyslexia were participants in a web-based survey. A total of 224 individuals completed the survey. These findings are from the 50 participants who reported to be 60 years or older. Completed measures include their perception of family support, emotional experience with dyslexia, self-esteem, and demographic variables. Preliminary analysis revealed that negative emotional experience with dyslexia negatively impacts self-esteem. Hierarchical moderated regression analysis demonstrated that positive perceived family support significantly buffers, mitigates, and protects the effects of negative emotional experiences with dyslexia on self-esteem in individuals with dyslexia in late adulthood. In this study, family support promoted self-esteem because as a protective dynamic, it helped older adults cope with the emotional distress associated with dyslexia. Implications of these findings are discussed.

From Languishing Dyslexia to Thriving Dyslexia: Developing a New Conceptual Approach to Working with People with Dyslexia

PubMed Central

Kannangara, Chathurika S.

2015-01-01

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

Dyslexic brain activation abnormalities in deep and shallow orthographies: A meta‐analysis of 28 functional neuroimaging studies

PubMed Central

Martin, Anna; Kronbichler, Martin

2016-01-01

Abstract We used coordinate‐based meta‐analysis to objectively quantify commonalities and differences of dyslexic functional brain abnormalities between alphabetic languages differing in orthographic depth. Specifically, we compared foci of under‐ and overactivation in dyslexic readers relative to nonimpaired readers reported in 14 studies in deep orthographies (DO: English) and in 14 studies in shallow orthographies (SO: Dutch, German, Italian, Swedish). The separate meta‐analyses of the two sets of studies showed universal reading‐related dyslexic underactivation in the left occipitotemporal cortex (including the visual word form area (VWFA)). The direct statistical comparison revealed higher convergence of underactivation for DO compared with SO in bilateral inferior parietal regions, but this abnormality disappeared when foci resulting from stronger dyslexic task‐negative activation (i.e., deactivation relative to baseline) were excluded. Higher convergence of underactivation for DO compared with SO was further identified in the left inferior frontal gyrus (IFG) pars triangularis, left precuneus, and right superior temporal gyrus, together with higher convergence of overactivation in the left anterior insula. Higher convergence of underactivation for SO compared with DO was found in the left fusiform gyrus, left temporoparietal cortex, left IFG pars orbitalis, and left frontal operculum, together with higher convergence of overactivation in the left precentral gyrus. Taken together, the findings support the notion of a biological unity of dyslexia, with additional orthography‐specific abnormalities and presumably different compensatory mechanisms. The results are discussed in relation to current functional neuroanatomical models of developmental dyslexia. Hum Brain Mapp 37:2676–2699, 2016. © 2016 The Authors Human Brain Mapping Published by Wiley Periodicals, Inc. PMID:27061464

Information Processing Differences and Similarities in Adults with Dyslexia and Adults with Attention Deficit Hyperactivity Disorder during a Continuous Performance Test: A Study of Cortical Potentials

ERIC Educational Resources Information Center

Dhar, Monica; Been, Pieter H.; Minderaa, Ruud B.; Althaus, Monika

2010-01-01

Twenty male adults with ADHD, 16 dyslexic adults, 15 comorbid adults, and 16 normal controls were compared on performance and underlying brain responses, during a cued Continuous Performance Test (O-X CPT), with the aim of discovering features of information processing differentiating between the groups. The study evaluated both cue- and…

Neural changes associated to procedural learning and automatization process in Developmental Coordination Disorder and/or Developmental Dyslexia.

PubMed

Biotteau, Maëlle; Péran, Patrice; Vayssière, Nathalie; Tallet, Jessica; Albaret, Jean-Michel; Chaix, Yves

2017-03-01

Recent theories hypothesize that procedural learning may support the frequent overlap between neurodevelopmental disorders. The neural circuitry supporting procedural learning includes, among others, cortico-cerebellar and cortico-striatal loops. Alteration of these loops may account for the frequent comorbidity between Developmental Coordination Disorder (DCD) and Developmental Dyslexia (DD). The aim of our study was to investigate cerebral changes due to the learning and automatization of a sequence learning task in children with DD, or DCD, or both disorders. fMRI on 48 children (aged 8-12) with DD, DCD or DD + DCD was used to explore their brain activity during procedural tasks, performed either after two weeks of training or in the early stage of learning. Firstly, our results indicate that all children were able to perform the task with the same level of automaticity, but recruit different brain processes to achieve the same performance. Secondly, our fMRI results do not appear to confirm Nicolson and Fawcett's model. The neural correlates recruited for procedural learning by the DD and the comorbid groups are very close, while the DCD group presents distinct characteristics. This provide a promising direction on the neural mechanisms associated with procedural learning in neurodevelopmental disorders and for understanding comorbidity. Published by Elsevier Ltd.

Phonological abilities in literacy-impaired children: Brain potentials reveal deficient phoneme discrimination, but intact prosodic processing.

PubMed

Männel, Claudia; Schaadt, Gesa; Illner, Franziska K; van der Meer, Elke; Friederici, Angela D

2017-02-01

Intact phonological processing is crucial for successful literacy acquisition. While individuals with difficulties in reading and spelling (i.e., developmental dyslexia) are known to experience deficient phoneme discrimination (i.e., segmental phonology), findings concerning their prosodic processing (i.e., suprasegmental phonology) are controversial. Because there are no behavior-independent studies on the underlying neural correlates of prosodic processing in dyslexia, these controversial findings might be explained by different task demands. To provide an objective behavior-independent picture of segmental and suprasegmental phonological processing in impaired literacy acquisition, we investigated event-related brain potentials during passive listening in typically and poor-spelling German school children. For segmental phonology, we analyzed the Mismatch Negativity (MMN) during vowel length discrimination, capturing automatic auditory deviancy detection in repetitive contexts. For suprasegmental phonology, we analyzed the Closure Positive Shift (CPS) that automatically occurs in response to prosodic boundaries. Our results revealed spelling group differences for the MMN, but not for the CPS, indicating deficient segmental, but intact suprasegmental phonological processing in poor spellers. The present findings point towards a differential role of segmental and suprasegmental phonology in literacy disorders and call for interventions that invigorate impaired literacy by utilizing intact prosody in addition to training deficient phonemic awareness. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Pituitary disorders as a predictor of apathy and executive dysfunction in adult survivors of childhood brain tumors.

PubMed

Fox, Michelle E; King, Tricia Z

2016-11-01

The relationship between apathy and endocrine dysfunction, both frequent outcomes of neurological insult, has not yet been investigated in brain tumor survivors. The present study aimed to assess the relationship between pituitary disorders and apathy and other facets of executive function in long-term adult survivors of childhood brain tumors and to differentiate between apathy and depression in this population. Seventy-six adult survivors of childhood brain tumors at least 5 years past diagnosis participated. An informant completed the Frontal Systems Behavior Scale (FrSBe), and 75 of the 76 participants completed a Structured Clinical Interview for the DSM-IV-TR (SCID). Information on neuroendocrine dysfunction was obtained through medical chart review. Clinically significant levels of apathy on the FrSBe were identified in 41% of survivors. Pituitary dysfunction significantly explained 9% of the variance in apathy scores and affected whether an individual presented with clinical levels of apathy. Pituitary dysfunction predicted higher levels of executive dysfunction but did not impact whether a participant reached clinical levels of executive dysfunction. A past major depressive episode (MDE) significantly predicted current apathy but showed no relationship with pituitary disorders. Radiation treatment predicted pituitary dysfunction but not the differences in apathy or executive functions. Apathy and executive dysfunction in survivors of childhood brain tumors are strongly predicted by pituitary dysfunction, and individuals with pituitary dysfunction are more likely to present with clinical levels of apathy as adults. Clinical levels of apathy may present absent of current depression, and pituitary dysfunction impacts apathy uniquely. © 2016 Wiley Periodicals, Inc.

Subtypes of developmental dyslexia: testing the predictions of the dual-route and connectionist frameworks.

PubMed

Peterson, Robin L; Pennington, Bruce F; Olson, Richard K

2013-01-01

We investigated the phonological and surface subtypes of developmental dyslexia in light of competing predictions made by two computational models of single word reading, the Dual-Route Cascaded Model (DRC; Coltheart, Rastle, Perry, Langdon, & Ziegler, 2001) and Harm and Seidenberg's connectionist model (HS model; Harm & Seidenberg, 1999). The regression-outlier procedure was applied to a large sample to identify children with disproportionately poor phonological coding skills (phonological dyslexia) or disproportionately poor orthographic coding skills (surface dyslexia). Consistent with the predictions of the HS model, children with "pure" phonological dyslexia, who did not have orthographic deficits, had milder phonological impairments than children with "relative" phonological dyslexia, who did have secondary orthographic deficits. In addition, pure cases of dyslexia were more common among older children. Consistent with the predictions of the DRC model, surface dyslexia was not well conceptualized as a reading delay; both phonological and surface dyslexia were associated with patterns of developmental deviance. In addition, some results were problematic for both models. We identified a small number of individuals with severe phonological dyslexia, relatively intact orthographic coding skills, and very poor real word reading. Further, a subset of controls could read normally despite impaired orthographic coding. The findings are discussed in terms of improvements to both models that might help better account for all cases of developmental dyslexia. Copyright © 2012 Elsevier B.V. All rights reserved.

Subtypes of developmental dyslexia: Testing the predictions of the dual-route and connectionist frameworks

PubMed Central

Peterson, Robin L.; Pennington, Bruce F.; Olson, Richard K.

2012-01-01

We investigated the phonological and surface subtypes of developmental dyslexia in light of competing predictions made by two computational models of single word reading, the dual-route cascaded model (DRC; Coltheart, Rastle, Perry, Langdon, & Ziegler, 2001) and Harm and Seidenberg’s connectionist model (HS model; Harm & Seidenberg, 1999). The regression-outlier procedure was applied to a large sample to identify children with disproportionately poor phonological coding skills (phonological dyslexia) or disproportionately poor orthographic coding skills (surface dyslexia). Consistent with the predictions of the HS model, children with “pure” phonological dyslexia, who did not have orthographic deficits, had milder phonological impairments than children with “relative” phonological dyslexia, who did have secondary orthographic deficits. In addition, pure cases of dyslexia were more common among older children. Consistent with the predictions of the DRC model, surface dyslexia was not well conceptualized as a reading delay; both phonological and surface dyslexia were associated with patterns of developmental deviance. In addition, some results were problematic for both models. We identified a small number of individuals with severe phonological dyslexia, relatively intact orthographic coding skills, and very poor real word reading. Further, a subset of controls could read normally despite impaired orthographic coding. The findings are discussed in terms of improvements to both models that might help better account for all cases of developmental dyslexia. PMID:23010562

A review of the neurobiological basis of dyslexia in the adult population.

PubMed

Soriano-Ferrer, M; Piedra Martínez, E

Adult dyslexia affects about 4% of the population. However, studies on the neurobiological basis of dyslexia in adulthood are scarce compared to paediatric studies. This review investigates the neurobiological basis of dyslexia in adulthood. Using PsycINFO, a database of psychology abstracts, we identified 11 studies on genetics, 9 neurostructural studies, 13 neurofunctional studies and 24 neurophysiological studies. Results from the review show that dyslexia is highly heritable and displays polygenic transmission. Likewise, adult neuroimaging studies found structural, functional, and physiological changes in the parieto-occipital and occipito-temporal regions, and in the inferior frontal gyrus, in adults with dyslexia. According to different studies, aetiology in cases of adult dyslexia is complex. We stress the need for neurobiological studies of dyslexia in languages with transparent spelling systems. Copyright © 2014 Sociedad Española de Neurología. Publicado por Elsevier España, S.L.U. All rights reserved.

Cognitive-linguistic performances of multilingual university students suspected of dyslexia.

PubMed

Lindgrén, Signe-Anita; Laine, Matti

2011-05-01

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 retrieval, phonological processing and other cognitive functions relevant for dyslexia. Reading and writing were examined in the two domestic languages, Swedish and Finnish. The most prominent group differences in reading and writing emerged on accuracy measures in both languages (reading text aloud, proofreading, writing to dictation, free writing). The dyslexia group also performed less well on speeded segmentation of written input, complex speeded naming and complex phoneme manipulation. The pattern of results fits the phonological deficit hypothesis of dyslexia and indicates the presence of pervasive underlying defects in compensated dyslexia. Copyright © 2010 John Wiley & Sons, Ltd.

Aggression and risk of future violence in forensic psychiatric patients with and without dyslexia.

PubMed

Selenius, Heidi; Hellström, Ake; Belfrage, Henrik

2011-05-01

Dyslexia does not cause criminal behaviour, but it may worsen aggressive behaviour tendencies. In this study, aggressive behaviour and risk of future violence were compared between forensic psychiatric patients with and without dyslexia. Dyslexia was assessed using the Swedish phonological processing battery 'The Pigeon'. The patients filled in the Aggression Questionnaire, and trained assessors performed the risk assessments using HCR-20 version 2. Patients with dyslexia self-reported more aggressive behaviour compared with those without dyslexia. There was only a nearly significant tendency (p = 0.06) for the patients with dyslexia to receive higher scores in the HCR-20 compared with the patients without dyslexia, and phonological processing skills did not significantly predict aggression or risk of future violence. However, regression analyses demonstrated that poor phonological processing skills are a significant predictor of anger, which in turn significantly predicts risk of future violence. Copyright © 2011 John Wiley & Sons, Ltd.

Dysfunction of mitochondrial dynamics in the brains of scrapie-infected mice

DOE Office of Scientific and Technical Information (OSTI.GOV)

Choi, Hong-Seok; Ilsong Institute of Life Science, Hallym University, 1605-4 Gwanyang-dong, Dongan-gu, Anyang, Gyeonggi-do 431-060; Choi, Yeong-Gon

Highlights: • Mfn1 and Fis1 are significantly increased in the hippocampal region of the ME7 prion-infected brain, whereas Dlp1 is significantly decreased in the infected brain. • Dlp1 is significantly decreased in the cytosolic fraction of the hippocampus in the infected brain. • Neuronal mitochondria in the prion-infected brains are enlarged and swollen compared to those of control brains. • There are significantly fewer mitochondria in the ME7-infected brain compared to the number in control brain. - Abstract: Mitochondrial dysfunction is a common and prominent feature of many neurodegenerative diseases, including prion diseases; it is induced by oxidative stress inmore » scrapie-infected animal models. In previous studies, we found swelling and dysfunction of mitochondria in the brains of scrapie-infected mice compared to brains of controls, but the mechanisms underlying mitochondrial dysfunction remain unclear. To examine whether the dysregulation of mitochondrial proteins is related to the mitochondrial dysfunction associated with prion disease, we investigated the expression patterns of mitochondrial fusion and fission proteins in the brains of ME7 prion-infected mice. Immunoblot analysis revealed that Mfn1 was up-regulated in both whole brain and specific brain regions, including the cerebral cortex and hippocampus, of ME7-infected mice compared to controls. Additionally, expression levels of Fis1 and Mfn2 were elevated in the hippocampus and the striatum, respectively, of the ME7-infected brain. In contrast, Dlp1 expression was significantly reduced in the hippocampus in the ME7-infected brain, particularly in the cytosolic fraction. Finally, we observed abnormal mitochondrial enlargement and histopathological change in the hippocampus of the ME7-infected brain. These observations suggest that the mitochondrial dysfunction, which is presumably caused by the dysregulation of mitochondrial fusion and fission proteins, may contribute to the neuropathological changes associated with prion disease.« less

Matrix Metalloproteinase-Mediated Blood-Brain Barrier Dysfunction in Epilepsy.

PubMed

Rempe, Ralf G; Hartz, Anika M S; Soldner, Emma L B; Sokola, Brent S; Alluri, Satya R; Abner, Erin L; Kryscio, Richard J; Pekcec, Anton; Schlichtiger, Juli; Bauer, Björn

2018-05-02

The blood-brain barrier is dysfunctional in epilepsy, thereby contributing to seizure genesis and resistance to antiseizure drugs. Previously, several groups reported that seizures increase brain glutamate levels, which leads to barrier dysfunction. One critical component of barrier dysfunction is brain capillary leakage. Based on our preliminary data, we hypothesized that glutamate released during seizures mediates an increase in matrix-metalloproteinase (MMP) expression and activity levels, thereby contributing to barrier leakage. To test this hypothesis, we exposed isolated brain capillaries from male Sprague Dawley rats to glutamate ex vivo and used an in vivo / ex vivo approach of isolated brain capillaries from female Wistar rats that experienced status epilepticus as an acute seizure model. We found that exposing isolated rat brain capillaries to glutamate increased MMP-2 and MMP-9 protein and activity levels, and decreased tight junction protein levels, which resulted in barrier leakage. We confirmed these findings in vivo in rats after status epilepticus and in brain capillaries from male mice lacking cytosolic phospholipase A 2 Together, our data support the hypothesis that glutamate released during seizures signals an increase in MMP-2 and MMP-9 protein expression and activity levels, resulting in blood-brain barrier leakage. SIGNIFICANCE STATEMENT The mechanism leading to seizure-mediated blood-brain barrier dysfunction in epilepsy is poorly understood. In the present study, we focused on defining this mechanism in the brain capillary endothelium. We demonstrate that seizures trigger a pathway that involves glutamate signaling through cytosolic phospholipase A 2 , which increases MMP levels and decreases tight junction protein expression levels, resulting in barrier leakage. These findings may provide potential therapeutic avenues within the blood-brain barrier to limit barrier dysfunction in epilepsy and decrease seizure burden. Copyright © 2018 the authors 0270-6474/18/384301-15$15.00/0.

Proton Magnetic Resonance Spectroscopy and MRI Reveal No Evidence for Brain Mitochondrial Dysfunction in Children with Autism Spectrum Disorder

ERIC Educational Resources Information Center

Corrigan, Neva M.; Shaw, Dennis. W. W.; Richards, Todd L.; Estes, Annette M.; Friedman, Seth D.; Petropoulos, Helen; Artru, Alan A.; Dager, Stephen R.

2012-01-01

Brain mitochondrial dysfunction has been proposed as an etiologic factor in autism spectrum disorder (ASD). Proton magnetic resonance spectroscopic imaging ([superscript 1]HMRS) and MRI were used to assess for evidence of brain mitochondrial dysfunction in longitudinal samples of children with ASD or developmental delay (DD), and cross-sectionally…

Are Students with Developmental Dyslexia Neurologically Different?

ERIC Educational Resources Information Center

Goldsmith-Phillips, Josephine

1994-01-01

Reviews the controversy over a biological basis for developmental dyslexia and illustrates it with two case studies of junior high school students. Reviews neurological evidence for developmental dyslexia, and proposes seven signs characteristic of reading disability that may qualify as dyslexia. (SR)

High Reading Skills Mask Dyslexia in Gifted Children.

PubMed

van Viersen, Sietske; Kroesbergen, Evelyn H; Slot, Esther M; de Bree, Elise H

2016-01-01

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. © Hammill Institute on Disabilities 2014.

How phonological awareness mediates the relation between working memory and word reading efficiency in children with dyslexia.

PubMed

Knoop-van Campen, Carolien A N; Segers, Eliane; Verhoeven, Ludo

2018-05-01

This study examined the relation between working memory, phonological awareness, and word reading efficiency in fourth-grade children with dyslexia. To test whether the relation between phonological awareness and word reading efficiency differed for children with dyslexia versus typically developing children, we assessed phonological awareness and word reading efficiency in 50 children with dyslexia (aged 9;10, 35 boys) and 613 typically developing children (aged 9;5, 279 boys). Phonological awareness was found to be associated with word reading efficiency, similar for children with dyslexia and typically developing children. To find out whether the relation between working memory and word reading efficiency in the group with dyslexia could be explained by phonological awareness, the children with dyslexia were also tested on working memory. Results of a mediation analysis showed a significant indirect effect of working memory on word reading efficiency via phonological awareness. Working memory predicted reading efficiency, via its relation with phonological awareness in children with dyslexia. This indicates that working memory is necessary for word reading efficiency via its impact on phonological awareness and that phonological awareness continues to be important for word reading efficiency in older children with dyslexia. © 2018 The Authors Dyslexia Published by John Wiley & Sons Ltd.

Compound mechanism hypothesis on +Gz induced brain injury and dysfunction of learning and memory

NASA Astrophysics Data System (ADS)

Sun, Xi-Qing; Li, Jin-Sheng; Cao, Xin-Sheng; Wu, Xing-Yu

2005-08-01

We systematically studied the effect of high- sustained +Gz on the brain and its mechanism in past ten years by animal centrifuge experiments. On the basis of the facts we observed and the more recent advances in acceleration physiology, we put forward a compound mechanism hypothesis to offer a possible explanation for +Gz-induced brain injury and dysfunction of learning and memory. It states that, ischemia during high G exposure might be the main factor accounting for +Gz-induced brain injury and dysfunction of learning and memory, including transient depression of brain energy metabolism, disturbance of ion homeostasis, increased blood-brain barrier permeability, increased brain nitric oxide synthase expression, and the protective effect of heat shock protein 70. In addition, the large rapid change of intracranial pressure and increased stress during +Gz exposure, and the hemorrheologic change after +Gz exposure might be one of the important factors accounting for +Gz-induced brain injury and dysfunction of learning and memory.

Hypothalamic digoxin and hemispheric chemical dominance: relation to speech and language dysfunction.

PubMed

Kurup, Ravi Kumar; Kurup, Parameswara Achutha

2003-06-01

The isoprenoid pathway produces three key metabolites--endogenous digoxin, dolichol, and ubiquinone. Since endogenous digoxin can regulate neurotransmitter transport and dolichols can modulate glycoconjugate synthesis important in synaptic connectivity, the pathway was assessed in patients with dyslexia, delayed recovery from global aphasia consequent to a dominant hemispheric thrombotic infarct, and developmental delay of speech milestone. The pathway was also studied in right hemispheric, left hemispheric, and bihemispheric dominance to find out the role of hemispheric dominance in the pathogenesis of speech disorders. The plasma/serum--activity of HMG CoA reductase, magnesium, digoxin, dolichol, ubiquinone--and tryptophan/tyrosine catabolic patterns, as well as RBC (Na+)-K+ ATPase activity, were measured in the above mentioned groups. The glycoconjugate metabolism and membrane composition was also studied. The study showed that in dyslexia, developmental delay of speech milestone, and delayed recovery from global aphasia there was an upregulated isoprenoidal pathway with increased digoxin and dolichol levels. The membrane (Na+)-K+ ATPase activity, serum magnesium and ubiquinone levels were low. The tryptophan catabolites were increased and the tyrosine catabolites including dopamine decreased in the serum contributing to a speech dysfunction. There was an increase in carbohydrate residues of glycoproteins, glycosaminoglycans, and glycolipids levels as well as an increased activity of GAG degrading enzymes and glyco hydrolases in the serum. The cholesterol:phospholipid ratio of RBC membrane increased and membrane glycoconjugates showed a decrease. All of these could contribute to altered synaptic inactivity in these disorders. The patterns correlated with those obtained in right hemispheric chemical dominance. Right hemispheric chemical dominance may play a role in the genesis of these disorders. Hemispheric chemical dominance has no correlation with handedness or the dichotic listening test.

Environmental Risk Factors in Han and Uyghur Children with Dyslexia: A Comparative Study.

PubMed

Zhao, Hua; Zhang, Baoping; Chen, Yun; Zhou, Xiang; Zuo, Pengxiang

2016-01-01

Several studies have been conducted to explore risk factors for dyslexia. However, most studies examining dyslexia have been skewed toward Western countries, and few have considered two nationalities simultaneously. This study focused on differences in dyslexia prevalence and potential environmental risk factors between Han and Uyghur children. A cross-sectional study was conducted in Kashgar and Aksu, cities in Xinjiang province, China. A two-stage sampling strategy was used to recruit 2,854 students in grades 3-6 from 5 primary schools in 5 districts; 2,348 valid student questionnaires were included in the analysis. Dyslexia checklists for Chinese and Uyghur children and pupil rating scales were used to identify children with dyslexia. Questions related to the home literacy environment and reading ability were used to evaluate potential environmental risk factors. Single factor analysis and multivariate logistic regression were used to examine prevalence and risk factors for dyslexia. Dyslexia prevalence differed significantly between Han (3.9%) and Uyghur (7.0%) children (P < 0.05), and the boy-to-girl diagnosis ratio was almost 2:1. Multiple logistic regression analysis showed that ethnic differences in dyslexia prevalence between Han and Uyghur children could have occurred because of factors such as mother's occupation (P = 0.02, OR = 0.04, 95% CI = 0.01-0.68) and the frequency with which parents told stories (P = 0.00, OR = 4.50, 95% CI = 1.67-12.11). The prevalence of dyslexia was high in all children, particularly those in the Uyghur group. Environmental factors could have been responsible for some of the differences observed. The results contribute to the early identification and management of dyslexia in children from these two groups and research examining developmental dyslexia and differences in racial genetics.

A few words about dyslexia.

PubMed

Peretz, Benny

2009-10-01

More and more, one encounters people who describe themselves as dyslectic. What is dyslexia? A detailed article in the July issue of Science, explains the phenomenon, and related aspects (1). The following are some of its points. Dyslexia is characterized by a difficulty is understanding and using alphabetic or logographic principles to acquire accurate and fluent reading skills. Dyslexia is persistent: a child who fails to read adequately in 1st grade has a high probability of reading poorly in 4th grade and in high school. Thus, difficulty in early reading limits reading comprehension in the later years of education, as students shift from learning to read to reading to learn. Dyslexia is often defined by a discrepancy between an average or above-average score on a test of general intelligence (intelligence quotient [IQ] test) and a low score on a standardized reading test. There is an observation that dyslexia is independent of other talents that allow some children with dyslexia to grow into re markably successful adults. Dyslexia is strongly heritable, occurring in up to 70% of identical twins and 50% of individuals who have a parent or sibling with dyslexia. Environmental factors are also important in reading development, even in children at genetic risk for dyslexia. Dyslexia can be treated. Once children are diagnosed with dyslexia because of reading failure, treatments are instructional. Instruction yields substantial improvement in reading accuracy for many, but not all, children if instruction is more intensive (for instance, 100 minutes per day for 8 weeks), occurs in small groups (1 or 2 students per teacher), and includes explicit and systematic instruction in phonological awareness and decoding strategies.

The human lexinome: Genes of language and reading

PubMed Central

Gibson, Christopher J.; Gruen, Jeffrey R.

2008-01-01

Within the human genome, genetic mapping studies have identified ten regions of different chromosomes, known as DYX loci, in genetic linkage with dyslexia, and two, known as SLI loci, in genetic linkage with Specific Language Impairment. Further genetic studies have identified four dyslexia genes within the DYX loci: DYX1C1 on 15q, KIAA0319 and DCDC2 on 6p22, and ROBO1on 13q. FOXP2 on 7q has been implicated in the development of Speech-Language Disorder. No genes for Specific Language impairment have yet been identified within the two SLI loci. Functional studies have shown that all four dyslexia genes play roles in brain development, and ongoing molecular studies are attempting to elucidate how these genes exert their effects at a subcellular level. Taken together, these genes and loci likely represent only a fraction of the human lexinome, a term we introduce here to refer to the collection of all the genetic and protein elements involved in the development of human language, expression, and reading. Learning outcomes The reader will become familiar with (i) methods for identifying genes for complex diseases, (ii) the application of these methods in the elucidation of genes underlying disorders of language and reading, and (iii) the cellular pathways through which polymorphisms in these genes may contribute to the development of the disorders. PMID:18466916

Five Describing Factors of Dyslexia

ERIC Educational Resources Information Center

Tamboer, Peter; Vorst, Harrie C. M.; Oort, Frans J.

2016-01-01

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…

Cognitive Endophenotypes of Dyslexia

ERIC Educational Resources Information Center

Moll, Kristina; Loff, Ariana; Snowling, Margaret J.

2013-01-01

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…

Teachers' Understandings, Perspectives, and Experiences of Dyslexia

ERIC Educational Resources Information Center

Worthy, Jo; DeJulio, Samuel; Svrcek, Natalie; Villarreal, Doris Ann; Derbyshire, Christine; LeeKeenan, Kira; Wiebe, Molly Trinh; Lammert, Catherine; Rubin, Jessica Cira; Salmerón, Cori

2016-01-01

Dyslexia policy and practice have been rapidly outpacing research. Due to legislation and media attention, schools are under pressure to attend to dyslexia, but research provides few clear answers about characteristics, identification, or instruction. Most dyslexia research takes place outside literacy education, and teachers' perspectives are…

Sound localization and word discrimination in reverberant environment in children with developmental dyslexia.

PubMed

Castro-Camacho, Wendy; Peñaloza-López, Yolanda; Pérez-Ruiz, Santiago J; García-Pedroza, Felipe; Padilla-Ortiz, Ana L; Poblano, Adrián; Villarruel-Rivas, Concepción; Romero-Díaz, Alfredo; Careaga-Olvera, Aidé

2015-04-01

Compare if localization of sounds and words discrimination in reverberant environment is different between children with dyslexia and controls. We studied 30 children with dyslexia and 30 controls. Sound and word localization and discrimination was studied in five angles from left to right auditory fields (-90o, -45o, 0o, +45o, +90o), under reverberant and no-reverberant conditions; correct answers were compared. Spatial location of words in no-reverberant test was deficient in children with dyslexia at 0º and +90o. Spatial location for reverberant test was altered in children with dyslexia at all angles, except –-90o. Word discrimination in no-reverberant test in children with dyslexia had a poor performance at left angles. In reverberant test, children with dyslexia exhibited deficiencies at -45o, -90o, and +45o angles. Children with dyslexia could had problems when have to locate sound, and discriminate words in extreme locations of the horizontal plane in classrooms with reverberation.

Coping successfully with dyslexia: an initial study of an inclusive school-based resilience programme.

PubMed

Firth, Nola; Frydenberg, Erica; Steeg, Charlotte; Bond, Lyndal

2013-05-01

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 programme and maintenance of effects for the students after transition to secondary school were investigated. Inclusion of contrast group data in the follow-up year suggested significant positive changes at first and second follow-ups in locus of control and nonproductive coping may also be associated with increase in age. Most trends were in the expected direction, especially for students with dyslexia. At follow-up, students with dyslexia reported similar perceived control and adaptive coping to students without dyslexia rather than a decrease in these areas as is usually the case. A larger sample and an ongoing control group are needed to confirm these results. Copyright © 2013 John Wiley & Sons, Ltd.

Auditory temporal processing skills in musicians with dyslexia.

PubMed

Bishop-Liebler, Paula; Welch, Graham; Huss, Martina; Thomson, Jennifer M; Goswami, Usha

2014-08-01

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. Copyright © 2014 John Wiley & Sons, Ltd.

Foundation doctors and dyslexia: a qualitative study of their experiences and coping strategies.

PubMed

Newlands, Freda; Shrewsbury, Duncan; Robson, Jean

2015-03-01

Dyslexia is the most common form of specific learning difficulty affecting approximately 6% of the general UK population and believed to affect approximately 2% of UK medical students. The impact of dyslexia on early practice has not been studied. To develop an understanding of the challenges faced by doctors with dyslexia in the first year of practice and their support requirements. Semistructured telephone interviews were conducted with seven foundation year 1 doctors with dyslexia from Scottish hospitals between March 2013 and August 2013. Foundation doctors indicated that due to their dyslexia, they experience difficulty with all forms of communication, time management and anxiety. There were concerns about disclosure of their dyslexia to colleagues and supervisors. Coping strategies used frequently were safety-netting and planning; technology solutions did offer some assistance. Although technological interventions have the potential to offer benefits to foundation doctors with dyslexia, increased openness about a diagnosis of dyslexia with discussion between doctor and supervisors about the challenges and anxieties is likely to provide the most benefit. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

The joint effects of risk status, gender, early literacy and cognitive skills on the presence of dyslexia among a group of high-risk Chinese children.

PubMed

Wong, Simpson W L; McBride-Chang, Catherine; Lam, Catherine; Chan, Becky; Lam, Fanny W F; Doo, Sylvia

2012-02-01

This study sought to examine factors that are predictive of future developmental dyslexia among a group of 5-year-old Chinese children at risk for dyslexia, including 62 children with a sibling who had been previously diagnosed with dyslexia and 52 children who manifested clinical at-risk factors in aspects of language according to testing by paediatricians. The age-5 performances on various literacy and cognitive tasks, gender and group status (familial risk or language delayed) were used to predict developmental dyslexia 2 years later using logistic regression analysis. Results showed that greater risk of dyslexia was related to slower rapid automatized naming, lower scores on morphological awareness, Chinese character recognition and English letter naming, and gender (boys had more risk). Three logistic equations were generated for estimating individual risk of dyslexia. The strongest models were those that included all print-related variables (including speeded number naming, character recognition and letter identification) and gender, with about 70% accuracy or above. Early identification of those Chinese children at risk for dyslexia can facilitate better dyslexia risk management. Copyright © 2012 John Wiley & Sons, Ltd.

Viral infection leading to brain dysfunction: more prevalent than appreciated?

PubMed Central

van den Pol, Anthony N.

2009-01-01

Virus infections of the brain can lead to transient or permanent neurologic or psychiatric dysfunction. Some of the complexities in establishing the causal role of viruses in brain disease are explored here. PMID:19840542

Functional Specialization in the Lower and Upper Visual Fields in Humans: Its Ecological Origins and Neurophysiological Implications

DTIC Science & Technology

1990-01-01

in that the with this hypothesis are the many reports (e.g., Adler - crossed-disparity system does appear to develop first Grinberg & Stark 1978... Rodman et al. 1986) that survives as independent of hemispheric asymmetries and additive to striate lesions critically depends on the superior...Perfomance. IRAAI human brain. No longer can visual cortical physiology Adler -Grinberg, D. & Stark, L. (1978) Eye movements, scanpaths, and dyslexia

Verbal and Non-verbal Fluency in Adults with Developmental Dyslexia: Phonological Processing or Executive Control Problems?

PubMed

Smith-Spark, James H; Henry, Lucy A; Messer, David J; Zięcik, Adam P

2017-08-01

The executive function of fluency describes the ability to generate items according to specific rules. Production of words beginning with a certain letter (phonemic fluency) is impaired in dyslexia, while generation of words belonging to a certain semantic category (semantic fluency) is typically unimpaired. However, in dyslexia, verbal fluency has generally been studied only in terms of overall words produced. Furthermore, performance of adults with dyslexia on non-verbal design fluency tasks has not been explored but would indicate whether deficits could be explained by executive control, rather than phonological processing, difficulties. Phonemic, semantic and design fluency tasks were presented to adults with dyslexia and without dyslexia, using fine-grained performance measures and controlling for IQ. Hierarchical regressions indicated that dyslexia predicted lower phonemic fluency, but not semantic or design fluency. At the fine-grained level, dyslexia predicted a smaller number of switches between subcategories on phonemic fluency, while dyslexia did not predict the size of phonemically related clusters of items. Overall, the results suggested that phonological processing problems were at the root of dyslexia-related fluency deficits; however, executive control difficulties could not be completely ruled out as an alternative explanation. Developments in research methodology, equating executive demands across fluency tasks, may resolve this issue. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

Simulation of dyslexia. How literacy and cognitive skills can help distinguish college students with dyslexia from malingerers

PubMed Central

de Bree, Elise H.; de Jong, Peter F.

2018-01-01

Academic accommodations associated with a diagnosis of dyslexia might be incentives for college students without reading or spelling difficulties to feign dyslexia and obtain the diagnosis unfairly. In the current study we examined malingering practices by comparing the performance of college students instructed to malinger dyslexia (n = 28) to that of students actually diagnosed with dyslexia (n = 16). We also included a control group of students without reading and spelling difficulties (n = 28). The test battery included tasks tapping literacy skills as well as underlying cognitive skills associated with literacy outcomes. These tasks are commonly used in diagnosing dyslexia. We examined patterns in the performance of malingerers across tasks and tested whether malingerers could be identified based on their performance on a limited number of tasks. Results indicated that malingerers scored significantly lower than students with dyslexia on reading and spelling skills; i.e., the core characteristics of dyslexia. Especially reading performance was extremely low and not in line with students’ age and level of education. Findings for underlying cognitive skills were mixed. Overall, malingerers scored lower than students with dyslexia on tasks tapping mainly speed, whereas the two groups did not differ on tasks reflecting mainly accuracy. Based on word and pseudoword reading and letter and digit naming, the three groups could be distinguished with reasonable sensitivity and specificity. In all, results indicate that college students seem to understand on which tasks they should feign dyslexia, but tend to exaggerate difficulties on these tasks to the point where diagnosticians should mistrust performance. PMID:29782515

Foreign language reading and spelling in gifted students with dyslexia in secondary education.

PubMed

van Viersen, Sietske; de Bree, Elise H; Kalee, Lilian; Kroesbergen, Evelyn H; de Jong, Peter F

2017-01-01

A few studies suggest that gifted children with dyslexia have better literacy skills than averagely intelligent children with dyslexia. This finding aligns with the hypothesis that giftedness-related factors provide compensation for poor reading. The present study investigated whether, as in the native language (NL), the level of foreign language (FL) literacy of gifted students with dyslexia is higher than the literacy level of averagely intelligent students with dyslexia and whether this difference can be accounted for by the difference in their NL literacy level. The sample consisted of 148 Dutch native speaking secondary school students divided in four groups: dyslexia, gifted/dyslexia, typically developing (TD), and gifted. All students were assessed on word reading and orthographic knowledge in Dutch and English when they were in 7th or 8th grade. A subsample ( n  = 71) was (re)assessed on Dutch, English, French, and German literacy one year later. Results showed that Dutch gifted students with dyslexia have higher NL literacy levels than averagely intelligent students with dyslexia. As in the NL, a stepwise pattern of group differences was found for English word reading and spelling, i.e., dyslexia < gifted/dyslexia < TD < gifted. However, it was not found for French and German literacy performance. These results point towards compensation: the higher English literacy levels of gifted/dyslexic students compared to their averagely intelligent dyslexic peers result from mechanisms that are unique to English as a FL. Differences in results between FLs are discussed in terms of variation in orthographic transparency and exposure.

Coexisting Problem Behaviour in Severe Dyslexia

ERIC Educational Resources Information Center

Dahle, Anne Elisabeth; Knivsberg, Ann-Mari; Andreassen, Anne Brit

2011-01-01

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…

Naming Speed in Dyslexia and Dyscalculia

ERIC Educational Resources Information Center

Willburger, Edith; Fussenegger, Barbara; Moll, Kristina; Wood, Guilherme; Landerl, Karin

2008-01-01

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…

DYSLEXIA--IS THERE SUCH A THING.

ERIC Educational Resources Information Center

BOTEL, MORTON

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)…

Developmental Dyslexia as Developmental and Linguistic Variation: Editor's Commentary.

ERIC Educational Resources Information Center

Leong, Che Kan

2002-01-01

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…

Cognitive Linguistic Performances of Multilingual University Students Suspected of Dyslexia

ERIC Educational Resources Information Center

Lindgren, Signe-Anita; Laine, Matti

2011-01-01

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…

Learners with Dyslexia: Exploring Their Experiences with Different Online Reading Affordances

ERIC Educational Resources Information Center

Chen, Chwen Jen; Keong, Melissa Wei Yin; Teh, Chee Siong; Chuah, Kee Man

2015-01-01

To date, empirically derived guidelines for designing accessible online learning environments for learners with dyslexia are still scarce. This study aims to explore the learning experience of learners with dyslexia when reading passages using different online reading affordances to derive some guidelines for dyslexia-friendly online text. The…

Learned Helplessness and Dyslexia: A Carts and Horses Issue?

ERIC Educational Resources Information Center

Kerr, H.

2001-01-01

Surveys attitudes towards and beliefs about dyslexia among Adult Basic Education (ABE) teachers and providers. Finds doubt, uncertainty and confusion about dyslexia and considerable misgiving. Discusses attribution theory and learned helplessness in the context of ABE. Argues that a diagnosis of dyslexia may be a maladaptive attribution and so…

Dyslexia Limits the Ability to Categorize Talker Dialect

ERIC Educational Resources Information Center

Long, Gayle Beam; Fox, Robert Allen; Jacewicz, Ewa

2016-01-01

Purpose: The purpose of this study was to determine whether the underlying phonological impairment in dyslexia is associated with a deficit in categorizing regional dialects. Method: Twenty adults with dyslexia, 20 school-age children with dyslexia, and 40 corresponding control listeners with average reading ability listened to sentences produced…

Developing an Ambivalence Perspective on Medical Labelling in Education: Case Dyslexia

ERIC Educational Resources Information Center

Solvang, Per

2007-01-01

There are several social actors involved in the process of constructing the social meaning of dyslexia--namely, parents, teachers, educational authorities and organisations representing dyslectics. Some of these actors emphasise the constructive social powers related to the dyslexia label, while others perceive dyslexia as diagnostic reasoning…

Vascular impairment as a pathological mechanism underlying long-lasting cognitive dysfunction after pediatric traumatic brain injury.

PubMed

Ichkova, Aleksandra; Rodriguez-Grande, Beatriz; Bar, Claire; Villega, Frederic; Konsman, Jan Pieter; Badaut, Jerome

2017-12-01

Traumatic brain injury (TBI) is the leading cause of death and disability in children. Indeed, the acute mechanical injury often evolves to a chronic brain disorder with long-term cognitive, emotional and social dysfunction even in the case of mild TBI. Contrary to the commonly held idea that children show better recovery from injuries than adults, pediatric TBI patients actually have worse outcome than adults for the same injury severity. Acute trauma to the young brain likely interferes with the fine-tuned developmental processes and may give rise to long-lasting consequences on brain's function. This review will focus on cerebrovascular dysfunction as an important early event that may lead to long-term phenotypic changes in the brain after pediatric TBI. These, in turn may be associated with accelerated brain aging and cognitive dysfunction. Finally, since no effective treatments are currently available, understanding the unique pathophysiological mechanisms of pediatric TBI is crucial for the development of new therapeutic options. Copyright © 2017 Elsevier Ltd. All rights reserved.

Omega-3 and dyslexia

PubMed Central

Zelcer, Michal; Goldman, Ran D.

2015-01-01

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

Socially Desirable Responding and College Students with Dyslexia: Implications for the Assessment of Anxiety and Depression.

PubMed

Nelson, Jason M; Liebel, Spencer W

2018-02-01

We investigated self-reported depressive and anxiety-related symptoms among college students with dyslexia, with emphasis on the role of socially desirable responding (SDR) in understanding these reports. Analyses included examination of differences in self-reported depressive symptoms, anxiety-related symptoms, and SDR. We also examined the relationships among SDR, depressive symptoms, anxiety-related symptoms, and reading skills. Participants with dyslexia demonstrated significantly higher SDR than did participants without dyslexia, and higher SDR was significantly associated with lower self-reported depressive and anxiety-related symptoms. Moreover, higher SDR was significantly associated with lower reading skills. There was no group difference on anxiety-related symptoms, but participants with dyslexia had higher depressive symptoms than did participants without dyslexia when SDR was controlled. Implications for the assessment of anxiety and depression among college students with dyslexia are discussed. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

Psychological Well-being Trajectories of Individuals with Dyslexia Aged 3-11 Years.

PubMed

Jordan, Julie-Ann; Dyer, Kevin

2017-05-01

Dyslexia has been associated with a range of psychological well-being issues in childhood. However, it is unclear if these difficulties stem from coping with academic struggles at school, or from other pre-existing diagnoses that sometimes co-occur with dyslexia. Using UK Millennium Cohort Study data (n = 7224) from 2003 to 2011, the present study compared psychological well-being development from ages 3-11 years for children with (1) dyslexia only; (2) special educational needs excluding dyslexia; (3) comorbid dyslexia and other special educational needs; and (4) no special educational needs. Growth curve modelling results controlling for race, gender, age and family income suggested that with the exception of conduct difficulties, psychological well-being issues related to dyslexia do not occur preschool; rather, they commence upon starting school. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

A survey-based exploration of the impact of dyslexia on career progression of UK registered nurses.

PubMed

Morris, David; Turnbull, Patricia

2007-01-01

To explore the effects of dyslexia on the practice and career progression of UK registered nurses (RN). Literature suggests dyslexia can have a negative impact in the workplace and may pose particular difficulties for nurses, where accuracy in information processing activities is essential for practice. A questionnaire was used to survey RNs with dyslexia (n = 116) and results analysed using content analysis. Dyslexia provided a challenge to the everyday work of RNs, which was often met successfully using a range of individualized strategies. Career progression was achievable but compared with peers, was perceived to take longer. Disclosure of dyslexia to work-colleagues was selective and dependent on the perceived benefits. Informal support mechanisms were commonly utilized with formal management support less well defined. Dyslexia appears to have a negative impact on working practices and career progression, but remains a poorly understood and often hidden disability.

Children with Specific Language Impairment are not impaired in the acquisition and retention of Pavlovian delay and trace conditioning of the eyeblink response☆

PubMed Central

Hardiman, Mervyn J.; Hsu, Hsin-jen; Bishop, Dorothy V.M.

2013-01-01

Three converging lines of evidence have suggested that cerebellar abnormality is implicated in developmental language and literacy problems. First, some brain imaging studies have linked abnormalities in cerebellar grey matter to dyslexia and specific language impairment (SLI). Second, theoretical accounts of both dyslexia and SLI have postulated impairments of procedural learning and automatisation of skills, functions that are known to be mediated by the cerebellum. Third, motor learning has been shown to be abnormal in some studies of both disorders. We assessed the integrity of face related regions of the cerebellum using Pavlovian eyeblink conditioning in 7–11 year-old children with SLI. We found no relationship between oral language skills or literacy skills with either delay or trace conditioning in the children. We conclude that this elementary form of associative learning is intact in children with impaired language or literacy development. PMID:24139661

Aggression and Risk of Future Violence in Forensic Psychiatric Patients with and without Dyslexia

ERIC Educational Resources Information Center

Selenius, Heidi; Hellstrom, Ake; Belfrage, Henrik

2011-01-01

Dyslexia does not cause criminal behaviour, but it may worsen aggressive behaviour tendencies. In this study, aggressive behaviour and risk of future violence were compared between forensic psychiatric patients with and without dyslexia. Dyslexia was assessed using the Swedish phonological processing battery "The Pigeon". The patients…

"Just Deal with It": Neoliberalism in Dyslexic Students' Talk about Dyslexia and Learning at University

ERIC Educational Resources Information Center

Cameron, Harriet; Billington, Tom

2017-01-01

There are different ways of theorising dyslexia and different ways of constructing meanings around dyslexia in different learning contexts. This paper considers the role of neoliberalist ideology in shaping conversations about dyslexia and "fairness" during two focus group conversations analysed as part of a study into the discursive…

Reading Difficulties in Spanish Adults with Dyslexia

ERIC Educational Resources Information Center

Suárez-Coalla, Paz; Cuetos, Fernando

2015-01-01

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…

Factors Associated with Successful Learning in Pupils with Dyslexia: A Motivational Analysis

ERIC Educational Resources Information Center

Burden, Robert; Burdett, Julia

2005-01-01

In 2002, Neil Humphrey and Patricia Mullins published their research into personal constructs and attribution for academic success and failure in dyslexia in BJSE's "Research Section". Their work suggested that pupils with dyslexia, in a range of settings, experience real challenges to their self-esteem and that dyslexia leads to "negative…

Identification of Students with Dyslexia in California Public Schools

ERIC Educational Resources Information Center

Futterman, Kathy R.

2017-01-01

One of the key problems facing public education today is the need for early and accurate identification of students with dyslexia. Students with dyslexia in public schools have historically been largely ignored or under-identified. California public school educators and administrators need to understand what dyslexia is and how to accurately…

Developmental Dyslexia: Predicting Individual Risk

ERIC Educational Resources Information Center

Thompson, Paul A.; Hulme, Charles; Nash, Hannah M.; Gooch, Debbie; Hayiou-Thomas, Emma; Snowling, Margaret J.

2015-01-01

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…

Connectionist neuropsychology: uncovering ultimate causes of acquired dyslexia.

PubMed

Woollams, Anna M

2014-01-01

Acquired dyslexia offers a unique window on to the nature of the cognitive and neural architecture supporting skilled reading. This paper provides an integrative overview of recent empirical and computational work on acquired dyslexia within the context of the primary systems framework as implemented in connectionist neuropsychological models. This view proposes that damage to general visual, phonological or semantic processing abilities are the root causes of different forms of acquired dyslexia. Recent case-series behavioural evidence concerning pure alexia, phonological dyslexia and surface dyslexia that supports this perspective is presented. Lesion simulations of these findings within connectionist models of reading demonstrate the viability of this approach. The commitment of such models to learnt representations allows them to capture key aspects of performance in each type of acquired dyslexia, particularly the associated non-reading deficits, the role of relearning and the influence of individual differences in the premorbid state of the reading system. Identification of these factors not only advances our understanding of acquired dyslexia and the mechanisms of normal reading but they are also relevant to the complex interactions underpinning developmental reading disorders.

Exploring the learning experiences of nursing students with dyslexia.

PubMed

Child, J; Langford, E

To examine the learning experiences of nursing students with dyslexia during clinical placements to establish ways of improving support in practice, A phenomenological lifeworld approach was adopted using semi-structured interviews. Students reflected on their experiences during clinical placements, allowing the researcher to gain an in-depth knowledge of the students' lived experience of dyslexia. Twelve student nurses, six with dyslexia and six without, were interviewed using a standard set of questions, and the data were collated and analysed. Using a comparison group of students without dyslexia was felt to be important to contextualise and compare the students' experiences. Three main themes emerged: the value of work-based learning days, the importance of the clinical placement mentor role and the need for advocacy. Both groups of nursing students contributed to recommendations relating to support in practice and those with dyslexia also shared their individual coping strategies, Nursing students with dyslexia may benefit from sharing placement experiences with colleagues outside the clinical environment. They may also benefit from receiving support from their placement mentor and a representative from the university who knows about dyslexia.

Connectionist neuropsychology: uncovering ultimate causes of acquired dyslexia

PubMed Central

Woollams, Anna M.

2014-01-01

Acquired dyslexia offers a unique window on to the nature of the cognitive and neural architecture supporting skilled reading. This paper provides an integrative overview of recent empirical and computational work on acquired dyslexia within the context of the primary systems framework as implemented in connectionist neuropsychological models. This view proposes that damage to general visual, phonological or semantic processing abilities are the root causes of different forms of acquired dyslexia. Recent case-series behavioural evidence concerning pure alexia, phonological dyslexia and surface dyslexia that supports this perspective is presented. Lesion simulations of these findings within connectionist models of reading demonstrate the viability of this approach. The commitment of such models to learnt representations allows them to capture key aspects of performance in each type of acquired dyslexia, particularly the associated non-reading deficits, the role of relearning and the influence of individual differences in the premorbid state of the reading system. Identification of these factors not only advances our understanding of acquired dyslexia and the mechanisms of normal reading but they are also relevant to the complex interactions underpinning developmental reading disorders. PMID:24324241

Inhibition and Updating, but Not Switching, Predict Developmental Dyslexia and Individual Variation in Reading Ability

PubMed Central

Doyle, Caoilainn; Smeaton, Alan F.; Roche, Richard A. P.; Boran, Lorraine

2018-01-01

To elucidate the core executive function profile (strengths and weaknesses in inhibition, updating, and switching) associated with dyslexia, this study explored executive function in 27 children with dyslexia and 29 age matched controls using sensitive z-mean measures of each ability and controlled for individual differences in processing speed. This study found that developmental dyslexia is associated with inhibition and updating, but not switching impairments, at the error z-mean composite level, whilst controlling for processing speed. Inhibition and updating (but not switching) error composites predicted both dyslexia likelihood and reading ability across the full range of variation from typical to atypical. The predictive relationships were such that those with poorer performance on inhibition and updating measures were significantly more likely to have a diagnosis of developmental dyslexia and also demonstrate poorer reading ability. These findings suggest that inhibition and updating abilities are associated with developmental dyslexia and predict reading ability. Future studies should explore executive function training as an intervention for children with dyslexia as core executive functions appear to be modifiable with training and may transfer to improved reading ability. PMID:29892245

Socioemotional Features and Resilience in Italian University Students with and without Dyslexia

PubMed Central

Ghisi, Marta; Bottesi, Gioia; Re, Anna M.; Cerea, Silvia; Mammarella, Irene C.

2016-01-01

Dyslexia is a permanent condition characterized by reading difficulties that include inaccurate or slow and effortful word reading, poor decoding, and poor spelling abilities. People with dyslexia may have psychological and psychopathological issues such as low self-esteem, poor resilience, and symptoms of depression and anxiety. They may also develop social problems and emotional issues, as well as low academic and social self-efficacy. The present study aimed to assess the psychological features of a sample of 28 Italian university students with dyslexia, comparing them with a control group of typically developing students matched for gender, education, and academic discipline, to enhance our knowledge of dyslexia outcomes in an Italian setting. The results show that university students with dyslexia experience higher levels of somatic complaints, social and attentional problems, lower self-esteem, and higher depression scores than controls, while no difference emerged between the two groups’ resilience scores. In conclusion, the present findings suggest that university students with dyslexia report more psychological issues than students without dyslexia and could benefit from intervention to improve their psychological and physical well-being. PMID:27065220

Dyslexia Limits the Ability to Categorize Talker Dialect

PubMed Central

Long, Gayle Beam; Jacewicz, Ewa

2016-01-01

Purpose The purpose of this study was to determine whether the underlying phonological impairment in dyslexia is associated with a deficit in categorizing regional dialects. Method Twenty adults with dyslexia, 20 school-age children with dyslexia, and 40 corresponding control listeners with average reading ability listened to sentences produced by multiple talkers (both sexes) representing two dialects: Midland dialect in Ohio (same as listeners' dialect) and Southern dialect in Western North Carolina. Participants' responses were analyzed using signal detection theory. Results Listeners with dyslexia were less sensitive to talker dialect than listeners with average reading ability. Children were less sensitive to dialect than adults. Under stimulus uncertainty, listeners with average reading ability were biased toward Ohio dialect, whereas listeners with dyslexia were unbiased in their responses. Talker sex interacted with sensitivity and bias differently for listeners with dyslexia than for listeners with average reading ability. The correlations between dialect sensitivity and phonological memory scores were strongest for adults with dyslexia. Conclusions The results imply that the phonological deficit in dyslexia arises from impaired access to intact phonological representations rather than from poorly specified representations. It can be presumed that the impeded access to implicit long-term memory representations for indexical (dialect) information is due to less efficient operations in working memory, including deficiencies in utilizing talker normalization processes. PMID:27575597

Early dynamics of white matter deficits in children developing dyslexia.

PubMed

Vanderauwera, Jolijn; Wouters, Jan; Vandermosten, Maaike; Ghesquière, Pol

2017-10-01

Neural anomalies have been demonstrated in dyslexia. Recent studies in pre-readers at risk for dyslexia and in pre-readers developing poor reading suggest that these anomalies might be a cause of their reading impairment. Our study goes one step further by exploring the neurodevelopmental trajectory of white matter anomalies in pre-readers with and without a familial risk for dyslexia (n=61) of whom a strictly selected sample develops dyslexia later on (n=15). We collected longitudinal diffusion MRI and behavioural data until grade 3. The results provide evidence that children with dyslexia exhibit pre-reading white matter anomalies in left and right long segment of the arcuate fasciculus (AF), with predictive power of the left segment above traditional cognitive measures and familial risk. Whereas white matter differences in the left AF seem most strongly related to the development of dyslexia, differences in the left IFOF and in the right AF seem driven by both familial risk and later reading ability. Moreover, differences in the left AF appeared to be dynamic. This study supports and expands recent insights into the neural basis of dyslexia, pointing towards pre-reading anomalies related to dyslexia, as well as underpinning the dynamic character of white matter. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Screening for Dyslexia in French-Speaking University Students: An Evaluation of the Detection Accuracy of the Alouette Test.

PubMed

Cavalli, Eddy; Colé, Pascale; Leloup, Gilles; Poracchia-George, Florence; Sprenger-Charolles, Liliane; El Ahmadi, Abdessadek

Developmental dyslexia is a lifelong impairment affecting 5% to 10% of the population. In French-speaking countries, although a number of standardized tests for dyslexia in children are available, tools suitable to screen for dyslexia in adults are lacking. In this study, we administered the Alouette reading test to a normative sample of 164 French university students without dyslexia and a validation sample of 83 students with dyslexia. The Alouette reading test is designed to screen for dyslexia in children, since it taps skills that are typically deficient in dyslexia (i.e., phonological skills). However, the test's psychometric properties have not previously been available, and it is not standardized for adults. The results showed that, on the Alouette test, dyslexic readers were impaired on measures of accuracy, speed, and efficiency (accuracy/reading time). We also found significant correlations between the Alouette reading efficiency and phonological efficiency scores. Finally, in terms of the Alouette test, speed-accuracy trade-offs were found in both groups, and optimal cutoff scores were determined with receiver operator characteristic curves analysis, yielding excellent discriminatory power, with 83.1% sensitivity and 100% specificity for reading efficiency. Thus, this study supports the Alouette test as a sensitive and specific screening tool for adults with dyslexia.

Dyslexia as Disability or Handicap: When Does Vocabulary Matter?

ERIC Educational Resources Information Center

Elbro, Carsten

2010-01-01

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…

Response Inhibition and Its Relationship to Phonological Processing in Children with and without Dyslexia

ERIC Educational Resources Information Center

Schmid, Johanna M.; Labuhn, Andju S.; Hasselhorn, Marcus

2011-01-01

This study investigates response inhibition and its relationship to phonological processing in third-graders with and without dyslexia. Children with dyslexia (n = 20) and children without dyslexia (n = 16) were administered a stop signal task and a digit span forwards task. Initial analyses revealed phonological processing deficits in terms of a…

The Influence of Spelling Ability on Vocabulary Choices When Writing for Children with Dyslexia

ERIC Educational Resources Information Center

Sumner, Emma; Connelly, Vincent; Barnett, Anna L.

2016-01-01

Spelling is a prerequisite to expressing vocabulary in writing. Research has shown that children with dyslexia are hesitant spellers when composing. This study aimed to determine whether the hesitant spelling of children with dyslexia, evidenced by frequent pausing, affects vocabulary choices when writing. A total of 31 children with dyslexia,…

The Role of Categorical Speech Perception and Phonological Processing in Familial Risk Children with and without Dyslexia

ERIC Educational Resources Information Center

Hakvoort, Britt; de Bree, Elise; van der Leij, Aryan; Maassen, Ben; van Setten, Ellie; Maurits, Natasha; van Zuijen, Titia L.

2016-01-01

Purpose: This study assessed whether a categorical speech perception (CP) deficit is associated with dyslexia or familial risk for dyslexia, by exploring a possible cascading relation from speech perception to phonology to reading and by identifying whether speech perception distinguishes familial risk (FR) children with dyslexia (FRD) from those…

Adult Dyslexia and Attention Deficit Disorder in Finland--Project DyAdd: WAIS-III Cognitive Profiles

ERIC Educational Resources Information Center

Laasonen, Marja; Leppamaki, Sami; Tani, Pekka; Hokkanen, Laura

2009-01-01

The project Adult Dyslexia and Attention Deficit Disorder in Finland (Project DyAdd) compares adults (n = 119, 18-55 years) with dyslexia, attention-deficit/hyperactivity disorder (ADHD), dyslexia together with ADHD (comorbid), and healthy controls with neuropsychological, psychophysical, and biological methods. The focus of this article is on the…

Reading acceleration training changes brain circuitry in children with reading difficulties

PubMed Central

Horowitz-Kraus, Tzipi; Vannest, Jennifer J; Kadis, Darren; Cicchino, Nicole; Wang, Yingying Y; Holland, Scott K

2014-01-01

Introduction Dyslexia is characterized by slow, inaccurate reading. Previous studies have shown that the Reading Acceleration Program (RAP) improves reading speed and accuracy in children and adults with dyslexia and in typical readers across different orthographies. However, the effect of the RAP on the neural circuitry of reading has not been established. In the current study, we examined the effect of the RAP training on regions of interest in the neural circuitry for reading using a lexical decision task during fMRI in children with reading difficulties and typical readers. Methods Children (8–12 years old) with reading difficulties and typical readers were studied before and after 4 weeks of training with the RAP in both groups. Results In addition to improvements in oral and silent contextual reading speed, training-related gains were associated with increased activation of the left hemisphere in both children with reading difficulties and typical readers. However, only children with reading difficulties showed improvements in reading comprehension, which were associated with significant increases in right frontal lobe activation. Conclusions Our results demonstrate differential effects of the RAP on neural circuits supporting reading in both children with reading difficulties and typical readers and suggest that the intervention may stimulate use of typical neural circuits for reading and engage compensatory pathways to support reading in the developing brain of children with reading difficulties. PMID:25365797

CD40-CD40 Ligand Pathway is a Major Component of Acute Neuroinflammation and Contributes to Long-term Cognitive Dysfunction after Sepsis.

PubMed

Michels, Monique; Danieslki, Lucinéia Gainski; Vieira, Andriele; Florentino, Drielly; Dall'Igna, Dhébora; Galant, Letícia; Sonai, Beatriz; Vuolo, Francieli; Mina, Franciele; Pescador, Bruna; Dominguini, Diogo; Barichello, Tatiana; Quevedo, João; Dal-Pizzol, Felipe; Petronilho, Fabrícia

2015-03-26

Sepsis-associated encephalopathy (SAE) is associated with an increased rate of morbidity and mortality. It is not understood what the exact mechanism is for the brain dysfunction that occurs in septic patients, but brain inflammation and oxidative stress are a possible theory. Such events can occur through the alteration of molecules that perpetuate the inflammatory response. Thus, it is possible to postulate that CD40 may be involved in this process. The aim of this work is to evaluate the role of CD40-CD40L pathway activation in brain dysfunction associated with sepsis in an animal model. Microglia activation induces the upregulation of CD40-CD40L, both in vitro and in vivo. The inhibition of microglia activation decreases levels of CD40-CD40L in the brain and decreases brain inflammation, oxidative damage and blood brain barrier dysfunction. Despite this, anti-CD40 treatment does not improve mortality in this model. However, it is able to improve long-term cognitive impairment in sepsis survivors. In conclusion, there is a major involvement of the CD40-CD40L signaling pathway in long-term brain dysfunction in an animal model of sepsis.

CD40–CD40 Ligand Pathway Is a Major Component of Acute Neuroinflammation and Contributes to Long-term Cognitive Dysfunction after Sepsis

PubMed Central

Michels, Monique; Danieslki, Lucinéia Gainski; Vieira, Andriele; Florentino, Drielly; Dall’Igna, Dhébora; Galant, Letícia; Sonai, Beatriz; Vuolo, Francieli; Mina, Franciele; Pescador, Bruna; Dominguini, Diogo; Barichello, Tatiana; Quevedo, João; Dal-Pizzol, Felipe; Petronilho, Fabrícia

2015-01-01

Sepsis-associated encephalopathy (SAE) is associated with an increased rate of morbidity and mortality. It is not understood what the exact mechanism is for the brain dysfunction that occurs in septic patients, but brain inflammation and oxidative stress are a possible theory. Such events can occur through the alteration of molecules that perpetuate the inflammatory response. Thus, it is possible to postulate that CD40 may be involved in this process. The aim of this work is to evaluate the role of CD40–CD40L pathway activation in brain dysfunction associated with sepsis in an animal model. Microglia activation induces the upregulation of CD40–CD40L, both in vitro and in vivo. The inhibition of microglia activation decreases levels of CD40–CD40L in the brain and decreases brain inflammation, oxidative damage and blood brain barrier dysfunction. Despite this, anti-CD40 treatment does not improve mortality in this model. However, it is able to improve long-term cognitive impairment in sepsis survivors. In conclusion, there is a major involvement of the CD40–CD40L signaling pathway in long-term brain dysfunction in an animal model of sepsis. PMID:25822797

Development of the Korean Academy of Medical Sciences Guideline for Rating the Impairment in the Brain Injured and Brain Diseased Persons with Motor Dysfunction

PubMed Central

Baik, Jong Sam; Jang, Seong Ho; Park, Dong Sik

2009-01-01

To develop an objective and scientific method to evaluate the brain injured and brain diseased persons with motor dysfunction, American Medical Association's Guides to the Evaluation of Permanent Impairment was used as an exemplar. After the motor dysfunction due to brain injury or brain disease was confirmed, active range of motion and muscle strength of affected extremities were measured. Also, the total function of extremities was evaluated through the assessment of activities of daily living, fine coordination of hand, balance and gait. Then, the total score of manual muscle test and functional assessment of impaired upper and lower extremity were added, respectively. Spasticity of upper and lower extremity was used as minus factors. Patients with movement disorder such as Parkinson's disease were assessed based on the degree of dysfunction in response to medication. We develop a new rating system based on the concept of total score. PMID:19503680

Revisiting the "enigma" of musicians with dyslexia: Auditory sequencing and speech abilities.

PubMed

Zuk, Jennifer; Bishop-Liebler, Paula; Ozernov-Palchik, Ola; Moore, Emma; Overy, Katie; Welch, Graham; Gaab, Nadine

2017-04-01

Previous research has suggested a link between musical training and auditory processing skills. Musicians have shown enhanced perception of auditory features critical to both music and speech, suggesting that this link extends beyond basic auditory processing. It remains unclear to what extent musicians who also have dyslexia show these specialized abilities, considering often-observed persistent deficits that coincide with reading impairments. The present study evaluated auditory sequencing and speech discrimination in 52 adults comprised of musicians with dyslexia, nonmusicians with dyslexia, and typical musicians. An auditory sequencing task measuring perceptual acuity for tone sequences of increasing length was administered. Furthermore, subjects were asked to discriminate synthesized syllable continua varying in acoustic components of speech necessary for intraphonemic discrimination, which included spectral (formant frequency) and temporal (voice onset time [VOT] and amplitude envelope) features. Results indicate that musicians with dyslexia did not significantly differ from typical musicians and performed better than nonmusicians with dyslexia for auditory sequencing as well as discrimination of spectral and VOT cues within syllable continua. However, typical musicians demonstrated superior performance relative to both groups with dyslexia for discrimination of syllables varying in amplitude information. These findings suggest a distinct profile of speech processing abilities in musicians with dyslexia, with specific weaknesses in discerning amplitude cues within speech. Because these difficulties seem to remain persistent in adults with dyslexia despite musical training, this study only partly supports the potential for musical training to enhance the auditory processing skills known to be crucial for literacy in individuals with dyslexia. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Adults with developmental dyslexia show selective impairments in time-based and self-initiated prospective memory: Self-report and clinical evidence.

PubMed

Smith-Spark, James H; Zięcik, Adam P; Sterling, Christopher

2017-03-01

Prospective memory (PM; memory for delayed intentions) would seem to be impaired in dyslexia but evidence is currently limited in scope. There is a need, therefore, firstly, to explore PM under controlled conditions using a broader range of PM tasks than used previously and, secondly, to determine whether objectively measured and self-reported PM problems can be found in the same individuals with dyslexia. The responses of 30 adults with dyslexia were compared with those of 30 IQ-matched adults without dyslexia on a self-report and a clinical measure of PM. Dyslexia-related deficits were shown on the clinical measure overall and, more particularly, when PM responses had to be made to cues based on time rather than environmental events. Adults with dyslexia were also more likely to forget to carry out an intention under naturalistic conditions 24h later. On the self-report questionnaire, the group with dyslexia reported significantly more frequent problems with PM overall, despite using more techniques to aid their memory. In particular, problems were identified with longer-term PM tasks and PM which had to be self-initiated. Dyslexia-related PM deficits were found under both laboratory and everyday conditions in the same participants; the first time that this has been demonstrated. These findings support previous experimental research which has highlighted dyslexia-related deficits in PM when the enacting of intentions is based on time cues and/or has to be self-initiated rather than being in prompted by environmental events. Copyright © 2017 Elsevier Ltd. All rights reserved.

False memory for orthographically versus semantically similar words in adolescents with dyslexia: a fuzzy-trace theory perspective.

PubMed

Obidziński, Michał; Nieznański, Marek

2017-10-01

The presented research was conducted in order to investigate the connections between developmental dyslexia and the functioning of verbatim and gist memory traces-assumed in the fuzzy-trace theory. The participants were 71 high school students (33 with dyslexia and 38 without learning difficulties). The modified procedure and multinomial model of Stahl and Klauer (simplified conjoint recognition model) was used to collect and analyze data. Results showed statistically significant differences in four of the model parameters: (a) the probability of verbatim trace recollection upon presentation of orthographically similar stimulus was higher in the control than dyslexia group, (b) the probability of verbatim trace recollection upon presentation of semantically similar stimulus was higher in the control than dyslexia group, (c) the probability of gist trace retrieval upon presentation of semantically similar stimulus was higher in the dyslexia than control group, and (d) the probability of gist trace retrieval upon target stimulus presentation (in the semantic condition) was higher in the control than dyslexia group. The obtained results suggest differences of memory functioning in terms of verbatim and gist trace retrieval between people with and without dyslexia on specific, elementary cognitive processes postulated by the fuzzy-trace theory. These can indicate new approaches in the education of persons with developmental dyslexia, focused on specific impairments and the strengths of their memory functioning.

Prosodic Similarity Effects in Short-Term Memory in Developmental Dyslexia.

PubMed

Goswami, Usha; Barnes, Lisa; Mead, Natasha; Power, Alan James; Leong, Victoria

2016-11-01

Children with developmental dyslexia are characterized by phonological difficulties across languages. Classically, this 'phonological deficit' in dyslexia has been investigated with tasks using single-syllable words. Recently, however, several studies have demonstrated difficulties in prosodic awareness in dyslexia. Potential prosodic effects in short-term memory have not yet been investigated. Here we create a new instrument based on three-syllable words that vary in stress patterns, to investigate whether prosodic similarity (the same prosodic pattern of stressed and unstressed syllables) exerts systematic effects on short-term memory. We study participants with dyslexia and age-matched and younger reading-level-matched typically developing controls. We find that all participants, including dyslexic participants, show prosodic similarity effects in short-term memory. All participants exhibited better retention of words that differed in prosodic structure, although participants with dyslexia recalled fewer words accurately overall compared to age-matched controls. Individual differences in prosodic memory were predicted by earlier vocabulary abilities, by earlier sensitivity to syllable stress and by earlier phonological awareness. To our knowledge, this is the first demonstration of prosodic similarity effects in short-term memory. The implications of a prosodic similarity effect for theories of lexical representation and of dyslexia are discussed. © 2016 The Authors. Dyslexia published by John Wiley & Sons Ltd. © 2016 The Authors. Dyslexia published by John Wiley & Sons Ltd.

Children with Dyslexia Are Slow Writers Because They Pause More Often and Not Because They Are Slow at Handwriting Execution

ERIC Educational Resources Information Center

Sumner, Emma; Connelly, Vincent; Barnett, Anna L.

2013-01-01

It is commonly assumed that children with dyslexia are slower at handwriting than other children. However, evidence of slow handwriting in children with dyslexia is very mixed. Thirty-one children with dyslexia, aged 9 years, were compared to both age-matched children and younger spelling-ability matched children. Participants completed an…

Investigating Speech Perception in Children with Dyslexia: Is There Evidence of a Consistent Deficit in Individuals?

ERIC Educational Resources Information Center

Messaoud-Galusi, Souhila; Hazan, Valerie; Rosen, Stuart

2011-01-01

Purpose: The claim that speech perception abilities are impaired in dyslexia was investigated in a group of 62 children with dyslexia and 51 average readers matched in age. Method: To test whether there was robust evidence of speech perception deficits in children with dyslexia, speech perception in noise and quiet was measured using 8 different…

"I Don't Know What It Is to Be Able to Read": How Students with Dyslexia Experience Their Reading Impairment

ERIC Educational Resources Information Center

Wennas Brante, Eva

2013-01-01

Better understanding of the diverse reading abilities of people with dyslexia is necessary for the design of more effective learning situations, which are vital both to students with dyslexia and to their teachers. Seven individuals with dyslexia currently or formerly in higher education were interviewed about their reading experiences to learn…

Auditory Temporal Structure Processing in Dyslexia: Processing of Prosodic Phrase Boundaries Is Not Impaired in Children with Dyslexia

ERIC Educational Resources Information Center

Geiser, Eveline; Kjelgaard, Margaret; Christodoulou, Joanna A.; Cyr, Abigail; Gabrieli, John D. E.

2014-01-01

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…

Screening for Dyslexia in French-Speaking University Students: An Evaluation of the Detection Accuracy of the "Alouette" Test

ERIC Educational Resources Information Center

Cavalli, Eddy; Colé, Pascale; Leloup, Gilles; Poracchia-George, Florence; Sprenger-Charolles, Liliane; El Ahmadi, Abdessadek

2018-01-01

Developmental dyslexia is a lifelong impairment affecting 5% to 10% of the population. In French-speaking countries, although a number of standardized tests for dyslexia in children are available, tools suitable to screen for dyslexia in adults are lacking. In this study, we administered the "Alouette" reading test to a normative sample…

Evaluating the Impact of Dyslexia Laws on the Identification of Specific Learning Disability and Dyslexia

ERIC Educational Resources Information Center

Phillips, B. Anne Barber; Odegard, Timothy N.

2017-01-01

Dyslexia is a specific learning disability that impacts word reading accuracy and/or reading fluency. Over half of the states in the USA have passed legislation intended to promote better identification of individuals with dyslexia. To date, no study has been conducted to investigate the potential impact of state laws on the identification of…

Dyslexia and Voxel-Based Morphometry: Correlations between Five Behavioural Measures of Dyslexia and Gray and White Matter Volumes

ERIC Educational Resources Information Center

Tamboer, Peter; Scholte, H. Steven; Vorst, Harrie C. M.

2015-01-01

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…

The Dyslexia Handbook: Procedures Concerning Dyslexia and Related Disorders = Manual sobre la dislexia: Procedimientos relacionados con la dislexia y otros desordenes.

ERIC Educational Resources Information Center

Texas Education Agency, Austin.

This handbook, available in English and Spanish, contains the Texas State Board of Education's approved procedures concerning dyslexia and related disorders and information regarding the state's dyslexia statutes and their relation to the federal Rehabilitation Act of 1973, Section 504, and the Individuals with Disabilities Education Act. Chapters…

Analysing Conflicting Approaches to Dyslexia on a European Project: Moving to a More Strategic, Participatory, Strength-Based and Integrated Approach

ERIC Educational Resources Information Center

Davis, J. M.; Deponio, P.

2014-01-01

This paper draws from our experiences of an EU Life Long Learning Programme Project: GATE Understanding Dyslexia Phenomena Between Pre-Primary And Primary (2009-2011) to discuss different conceptual positions concerning dyslexia. It compares medical notions of dyslexia with perspectives from childhood and disability studies to question the ways in…

Postural Control in Children with Dyslexia: Effects of Emotional Stimuli in a Dual-Task Environment.

PubMed

Goulème, Nathalie; Gerard, Christophe-Loïc; Bucci, Maria Pia

2017-08-01

The aim of this study was to compare the visual exploration strategies used during a postural control task across participants with and without dyslexia. We simultaneously recorded eye movements and postural control while children were viewing different types of emotional faces. Twenty-two children with dyslexia and twenty-two aged-matched children without dyslexia participated in the study. We analysed the surface area, the length and the mean velocity of the centre of pressure for balance in parallel with visual saccadic latency, the number of saccades and the time spent in regions of interest. Our results showed that postural stability in children with dyslexia was weaker and the surface area of their centre of pressure increased significantly when they viewed an unpleasant face. Moreover, children with dyslexia had different strategies to those used by children without dyslexia during visual exploration, and in particular when they viewed unpleasant emotional faces. We suggest that lower performance in emotional face processing in children with dyslexia could be due to a difference in their visual strategies, linked to their identification of unpleasant emotional faces. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

The incidence of dyslexia among young offenders in Kuwait.

PubMed

Elbeheri, Gad; Everatt, John; Al Malki, Mohammad

2009-05-01

This paper investigates the incidence of dyslexia among young offenders in Kuwait. A total of 91 children/young adults from 8 juvenile delinquent welfare centres across Kuwait were interviewed and tested. A measure of non-verbal reasoning ability was used to exclude those with low general ability. The remaining 53 participants were tested on their ability to identify alliteration and rhyme, retain and manipulate sequences of digit and letter names, decode novel letter strings and identify words within letter chains. Participants' reading accuracy, rate of reading, reading comprehension and ability to spell correctly dictated text were also assessed. These measures were used to determine those with indicators of dyslexia. The results indicated that the percentage of individuals presenting evidence of dyslexia was much larger (greater than 20%) in this population of young offenders than would be expected based on the national average (around 6%) of dyslexics in Kuwait derived from a nationwide study (A survey study of dyslexia in Kuwait, Kuwait Dyslexia Association: Kuwait City; 2002). These findings replicate previous evidence for an increased frequency of dyslexia among young offenders. The implications of such findings are discussed in terms of dyslexia awareness, socio-cultural factors, education and intervention, particularly in Kuwait juvenile delinquent welfare centres.

Iron assessment to protect the developing brain.

PubMed

Georgieff, Michael K

2017-12-01

Iron deficiency (ID) before the age of 3 y can lead to long-term neurological deficits despite prompt diagnosis of ID anemia (IDA) by screening of hemoglobin concentrations followed by iron treatment. Furthermore, pre- or nonanemic ID alters neurobehavioral function and is 3 times more common than IDA in toddlers. Given the global prevalence of ID and the enormous societal cost of developmental disabilities across the life span, better methods are needed to detect the risk of inadequate concentrations of iron for brain development (i.e., brain tissue ID) before dysfunction occurs and to monitor its amelioration after diagnosis and treatment. The current screening and treatment strategy for IDA fails to achieve this goal for 3 reasons. First, anemia is the final state in iron depletion. Thus, the developing brain is already iron deficient when IDA is diagnosed owing to the prioritization of available iron to red blood cells over all other tissues during negative iron balance in development. Second, brain ID, independently of IDA, is responsible for long-term neurological deficits. Thus, starting iron treatment after the onset of IDA is less effective than prevention. Multiple studies in humans and animal models show that post hoc treatment strategies do not reliably prevent ID-induced neurological deficits. Third, most currently used indexes of ID are population statistical cutoffs for either hematologic or iron status but are not bioindicators of brain ID and brain dysfunction in children. Furthermore, their relation to brain iron status is not known. To protect the developing brain, there is a need to generate serum measures that index brain dysfunction in the preanemic stage of ID, assess the ability of standard iron indicators to detect ID-induced brain dysfunction, and evaluate the efficacy of early iron treatment in preventing ID-induced brain dysfunction. © 2017 American Society for Nutrition.

Adults with dyslexia demonstrate space-based and object-based covert attention deficits: shifting attention to the periphery and shifting attention between objects in the left visual field.

PubMed

Buchholz, Judy; Aimola Davies, Anne

2005-02-01

Performance on a covert visual attention task is compared between a group of adults with developmental dyslexia (specifically phonological difficulties) and a group of age and IQ matched controls. The group with dyslexia were generally slower to detect validly-cued targets. Costs of shifting attention toward the periphery when the target was invalidly cued were significantly higher for the group with dyslexia, while costs associated with shifts toward the fovea tended to be lower. Higher costs were also shown by the group with dyslexia for up-down shifts of attention in the periphery. A visual field processing difference was found, in that the group with dyslexia showed higher costs associated with shifting attention between objects in they LVF. These findings indicate that these adults with dyslexia have difficulty in both the space-based and the object-based components of covert visual attention, and more specifically to stimuli located in the periphery.

Familial history of reading difficulty is associated with diffused bilateral brain activation during reading and greater association with visual attention abilities.

PubMed

Horowitz-Kraus, Tzipi

2017-10-01

Reading difficulty (RD; or dyslexia) is a heritable condition characterized by slow, inaccurate reading accompanied by executive dysfunction, specifically with respect to visual attention. The current study was designed to examine the effect of familial history of RD on the relationship between reading and visual attention abilities in children with RD using a functional MRI reading task. Seventy-one children with RD participated in the study. Based on parental reports of the existence of RD in one or both of each child's parents, children with RD were divided into two groups: (1) those with a familial history of RD and (2) those without a familial history of RD. Reading and visual attention measures were collected from all participants. Functional MRI data during word reading was acquired in 30 participants of the entire cohort. Children with or without a familial history of RD demonstrated below-average reading and visual attention scores, with greater interaction between these measures in the group with a familial history of RD. Greater bilateral and diffused activation during word reading also were found in this group. We suggest that a familial history of RD is related to greater association between lower reading abilities and visual attention abilities. Parental history of RD therefore may be an important preschool screener (before reading age) to prompt early intervention focused on executive functions and reading-related skills.

A taxometric investigation of developmental dyslexia subtypes.

PubMed

O'Brien, Beth A; Wolf, Maryanne; Lovett, Maureen W

2012-02-01

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 severe reading disorders. Latent characteristics of the sample are assessed in regard to posited subtypes with phonological deficits and naming speed deficits, thus extending prior work by addressing whether these deficits embody separate classes of individuals. Findings support separate taxa of dyslexia with and without phonological deficits. Different latent structure for naming speed deficits was found depending on the definitional criterion used to define dyslexia. Non-phonologically based forms of dyslexia showed particular difficulty with naming speed and reading fluency. Copyright © 2012 John Wiley & Sons, Ltd.

What do preservice teachers from the USA and the UK know about dyslexia?

PubMed

Washburn, Erin K; Binks-Cantrell, Emily S; Joshi, R Malatesha

2014-02-01

The purpose of the study was to examine the knowledge base of preservice teachers from the USA and the UK of dyslexia as a language-based learning disability. A survey (both US and UK versions) was constructed using current research-based understandings of dyslexia as a language-based learning disability. One hundred and one preservice teachers from the USA and 70 preservice teachers from the UK were administered the survey. Results indicated that participants in the two groups demonstrated some similar accurate knowledge about dyslexia as well as displaying some common misunderstandings about dyslexia. Recommendations concerning preservice teacher preparation and professional development for in-service teachers about dyslexia as well as future research directions are discussed. Copyright © 2013 John Wiley & Sons, Ltd.

Dyslexia in general practice education: considerations for recognition and support.

PubMed

Shrewsbury, Duncan

2016-07-01

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.

Development of Tract-Specific White Matter Pathways During Early Reading Development in At-Risk Children and Typical Controls.

PubMed

Wang, Yingying; Mauer, Meaghan V; Raney, Talia; Peysakhovich, Barbara; Becker, Bryce L C; Sliva, Danielle D; Gaab, Nadine

2017-04-01

Developmental dyslexia is a neurodevelopmental disorder with a strong genetic basis. Previous studies observed white matter alterations in the left posterior brain regions in adults and school-age children with dyslexia. However, no study yet has examined the development of tract-specific white matter pathways from the pre-reading to the fluent reading stage in children at familial risk for dyslexia (FHD+) versus controls (FHD-). This study examined white matter integrity at pre-reading, beginning, and fluent reading stages cross-sectionally ( n = 78) and longitudinally (n = 45) using an automated fiber-tract quantification method. Our findings depict white matter alterations and atypical lateralization of the arcuate fasciculus at the pre-reading stage in FHD+ versus FHD- children. Moreover, we demonstrate faster white matter development in subsequent good versus poor readers and a positive association between white matter maturation and reading development using a longitudinal design. Additionally, the combination of white matter maturation, familial risk, and psychometric measures best predicted later reading abilities. Furthermore, within FHD+ children, subsequent good readers exhibited faster white matter development in the right superior longitudinal fasciculus compared with subsequent poor readers, suggesting a compensatory mechanism. Overall, our findings highlight the importance of white matter pathway maturation in the development of typical and atypical reading skills. Published by Oxford University Press 2016. This work is written by (a) US Government employee(s) and is in the public domain in the US.

Word Recognition and Cognitive Profiles of Chinese Pre-School Children at Risk for Dyslexia through Language Delay or Familial History of Dyslexia

ERIC Educational Resources Information Center

McBride-Chang, Catherine; Lam, Fanny; Lam, Catherine; Doo, Sylvia; Wong, Simpson W. L.; Chow, Yvonne Y. Y.

2008-01-01

Background: This study sought to identify cognitive abilities that might distinguish Hong Kong Chinese kindergarten children at risk for dyslexia through either language delay or familial history of dyslexia from children who were not at risk and to examine how these abilities were associated with Chinese word recognition. The cognitive skills of…

The Development of Children at Familial Risk for Dyslexia: Birth to Early School Age

ERIC Educational Resources Information Center

Lyytinen, Heikki; Aro, Mikko; Eklund, Kenneth; Erskine, Jane; Guttorm, Tomi; Laakso, Marja-Leena; Leppanen, Paavo H. T.; Lyytinen, Paula; Poikkeus, Anna-Maija; Richardson, Ulla; Torppa, Minna

2004-01-01

Children at risk for familial dyslexia (n = 107) and their controls (n = 93) have been followed from birth to school entry in the Jyvaskyla Longitudinal study of Dyslexia (JLD) on developmental factors linked to reading and dyslexia. At the point of school entry, the majority of the at-risk children displayed decoding ability that fell at least 1…

Music and Dyslexia: The Therapeutic Use of Instrument (Piano) Training with a Child with Dyslexia (A Case Study)

ERIC Educational Resources Information Center

Eren, Bilgehan

2017-01-01

Dyslexia is defined as a difficulty in learning at an expected level according to age, intelligence and education that is given, even though the intelligence level of the individual is normal or above normal. Individuals with dyslexia have difficulties in many developmental areas that can be considered in the scope of music therapy. Interventions…

Perceptual organization of speech signals by children with and without dyslexia

PubMed Central

Nittrouer, Susan; Lowenstein, Joanna H.

2013-01-01

Developmental dyslexia is a condition in which children encounter difficulty learning to read in spite of adequate instruction. Although considerable effort has been expended trying to identify the source of the problem, no single solution has been agreed upon. The current study explored a new hypothesis, that developmental dyslexia may be due to faulty perceptual organization of linguistically relevant sensory input. To test that idea, sentence-length speech signals were processed to create either sine-wave or noise-vocoded analogs. Seventy children between 8 and 11 years of age, with and without dyslexia participated. Children with dyslexia were selected to have phonological awareness deficits, although those without such deficits were retained in the study. The processed sentences were presented for recognition, and measures of reading, phonological awareness, and expressive vocabulary were collected. Results showed that children with dyslexia, regardless of phonological subtype, had poorer recognition scores than children without dyslexia for both kinds of degraded sentences. Older children with dyslexia recognized the sine-wave sentences better than younger children with dyslexia, but no such effect of age was found for the vocoded materials. Recognition scores were used as predictor variables in regression analyses with reading, phonological awareness, and vocabulary measures used as dependent variables. Scores for both sorts of sentence materials were strong predictors of performance on all three dependent measures when all children were included, but only performance for the sine-wave materials explained significant proportions of variance when only children with dyslexia were included. Finally, matching young, typical readers with older children with dyslexia on reading abilities did not mitigate the group difference in recognition of vocoded sentences. Conclusions were that children with dyslexia have difficulty organizing linguistically relevant sensory input, but learn to do so for the structure preserved by sine-wave signals before they do so for other sorts of signal structure. These perceptual organization deficits could account for difficulties acquiring refined linguistic representations, including those of a phonological nature, although ramifications are different across affected children. PMID:23702597

Perceptual organization of speech signals by children with and without dyslexia.

PubMed

Nittrouer, Susan; Lowenstein, Joanna H

2013-08-01

Developmental dyslexia is a condition in which children encounter difficulty learning to read in spite of adequate instruction. Although considerable effort has been expended trying to identify the source of the problem, no single solution has been agreed upon. The current study explored a new hypothesis, that developmental dyslexia may be due to faulty perceptual organization of linguistically relevant sensory input. To test that idea, sentence-length speech signals were processed to create either sine-wave or noise-vocoded analogs. Seventy children between 8 and 11 years of age, with and without dyslexia participated. Children with dyslexia were selected to have phonological awareness deficits, although those without such deficits were retained in the study. The processed sentences were presented for recognition, and measures of reading, phonological awareness, and expressive vocabulary were collected. Results showed that children with dyslexia, regardless of phonological subtype, had poorer recognition scores than children without dyslexia for both kinds of degraded sentences. Older children with dyslexia recognized the sine-wave sentences better than younger children with dyslexia, but no such effect of age was found for the vocoded materials. Recognition scores were used as predictor variables in regression analyses with reading, phonological awareness, and vocabulary measures used as dependent variables. Scores for both sorts of sentence materials were strong predictors of performance on all three dependent measures when all children were included, but only performance for the sine-wave materials explained significant proportions of variance when only children with dyslexia were included. Finally, matching young, typical readers with older children with dyslexia on reading abilities did not mitigate the group difference in recognition of vocoded sentences. Conclusions were that children with dyslexia have difficulty organizing linguistically relevant sensory input, but learn to do so for the structure preserved by sine-wave signals before they do so for other sorts of signal structure. These perceptual organization deficits could account for difficulties acquiring refined linguistic representations, including those of a phonological nature, although ramifications are different across affected children. Copyright © 2013 Elsevier Ltd. All rights reserved.

A Principled Relation between Reading and Naming in Acquired and Developmental Anomia: Surface Dyslexia Following Impairment in the Phonological Output Lexicon

PubMed Central

Gvion, Aviah; Friedmann, Naama

2016-01-01

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 it to lexical semantics. This pattern was shown both by the adults with acquired anomia and by the participants with developmental anomia. These results thus suggest a principled relation between anomia and dyslexia, and point to a distinct type of surface dyslexia. They further show the possibility of good comprehension of written words when the phonological output stages are impaired. PMID:27065897

The effect of learning on feedback-related potentials in adolescents with dyslexia: an EEG-ERP study.

PubMed

Kraus, Dror; Horowitz-Kraus, Tzipi

2014-01-01

Individuals with dyslexia exhibit associated learning deficits and impaired executive functions. The Wisconsin Card Sorting Test (WCST) is a learning-based task that relies heavily on executive functioning, in particular, attention shift and working memory. Performance during early and late phases of a series within the task represents learning and implementation of a newly learned rule. Here, we aimed to examine two event-related potentials associated with learning, feedback-related negativity (FRN)-P300 complex, in individuals with dyslexia performing the WCST. Adolescents with dyslexia and age-matched typical readers performed the Madrid card sorting test (MCST), a computerized version of the WCST. Task performance, reading measures, and cognitive measures were collected. FRN and the P300 complex were acquired using the event-related potentials methodology and were compared in early vs late errors within a series. While performing the MCST, both groups showed a significant reduction in average reaction times and a trend toward decreased error rates. Typical readers performed consistently better than individuals with dyslexia. FRN amplitudes in early phases were significantly smaller in dyslexic readers, but were essentially equivalent to typical readers in the late phase. P300 amplitudes were initially smaller among readers with dyslexia and tended to decrease further in late phases. Differences in FRN amplitudes for early vs late phases were positively correlated with those of P300 amplitudes in the entire sample. Individuals with dyslexia demonstrate a behavioral and electrophysiological change within single series of the MCST. However, learning patterns seem to differ between individuals with dyslexia and typical readers. We attribute these differences to the lower baseline performance of individuals with dyslexia. We suggest that these changes represent a fast compensatory mechanism, demonstrating the importance of learning strategies on reading among individuals with dyslexia.

Dyslexia Linked to Visual Strengths Useful in Astronomy

NASA Astrophysics Data System (ADS)

Schneps, Matthew H.; Brockmole, J. R.; Rose, L. T.; Pomplun, M.; Sonnert, G.; Greenhill, L. J.

2011-05-01

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 under Grants HRD-0726032 and HRD-0930962.

Cortical thickness abnormalities associated with dyslexia, independent of remediation status.

PubMed

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

2015-01-01

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.

Doctors with dyslexia: strategies and support.

PubMed

Locke, Rachel; Alexander, Gail; Mann, Richard; Kibble, Sharon; Scallan, Samantha

2017-10-01

Looking beyond dyslexia as an individual doctor's issue requires adjusting a working environment to better serve the needs of doctors with dyslexia. With an increasing number of doctors disclosing dyslexia at medical school, how can educators best provide this support? Our research looks at the impact of dyslexia on clinical practice and the coping strategies used by doctors to minimise the effect. Qualitative data were collected from 14 doctors with dyslexia using semi-structured interviews and by survey. 'In situ' demonstration interviews were conducted in order to understand how dyslexia is managed in the workplace from first-hand experience. Employers and educators who have responsibility for meeting the needs of this group were also consulted. Even in cases of doctors who had a diagnosis, they often did not disclose their dyslexia to their employer. Study participants reported having developed individual ways of coping and devised useful 'workarounds'. Support from employers comes in the form of 'reasonable adjustments', although from our data we cannot be sure that such adjustments contribute to an 'enabling' work environment. Supportive characteristics included the opportunity to shadow others and the time and space to complete paperwork on a busy ward. How can educators best provide support [for doctors with dyslexia]? Doctors with dyslexia need to be helped to feel comfortable enough to disclose. Educators need to challenge any negative assumptions that exist as well as promote understanding about the elements that contribute to a positive working environment. As a result of the research there is now practice available for educators to identify evidence-based strategies and resources. © 2016 John Wiley & Sons Ltd and The Association for the Study of Medical Education.

Cortical thickness abnormalities associated with dyslexia, independent of remediation status

PubMed Central

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

2014-01-01

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

Attention Dysfunction Subtypes of Developmental Dyslexia

PubMed Central

Lewandowska, Monika; Milner, Rafał; Ganc, Małgorzata; Włodarczyk, Elżbieta; Skarżyński, Henryk

2014-01-01

Background Previous studies indicate that many different aspects of attention are impaired in children diagnosed with developmental dyslexia (DD). The objective of the present study was to identify cognitive profiles of DD on the basis of attentional test performance. Material/Methods 78 children with DD (30 girls, 48 boys, mean age of 12 years ±8 months) and 32 age- and sex-matched non-dyslexic children (14 girls, 18 boys) were examined using a battery of standardized tests of reading, phonological and attentional processes (alertness, covert shift of attention, divided attention, inhibition, flexibility, vigilance, and visual search). Cluster analysis was used to identify subtypes of DD. Results Dyslexic children showed deficits in alertness, covert shift of attention, divided attention, flexibility, and visual search. Three different subtypes of DD were identified, each characterized by poorer performance on the reading, phonological awareness, and visual search tasks. Additionally, children in cluster no. 1 displayed deficits in flexibility and divided attention. In contrast to non-dyslexic children, cluster no. 2 performed poorer in tasks involving alertness, covert shift of attention, divided attention, and vigilance. Cluster no. 3 showed impaired covert shift of attention. Conclusions These results indicate different patterns of attentional impairments in dyslexic children. Remediation programs should address the individual child’s deficit profile. PMID:25387479

Defective chromatic and achromatic visual pathways in developmental dyslexia: Cues for an integrated intervention programme.

PubMed

Bonfiglio, Luca; Bocci, Tommaso; Minichilli, Fabrizio; Crecchi, Alessandra; Barloscio, Davide; Spina, Donata Maria; Rossi, Bruno; Sartucci, Ferdinando

2017-01-01

As well as obtaining confirmation of the magnocellular system involvement in developmental dyslexia (DD); the aim was primarily to search for a possible involvement of the parvocellular system; and, furthermore, to complete the assessment of the visual chromatic axis by also analysing the koniocellular system. Visual evoked potentials (VEPs) in response to achromatic stimuli with low luminance contrast and low spatial frequency, and isoluminant red/green and blue/yellow stimuli with high spatial frequency were recorded in 10 dyslexic children and 10 age- and sex-matched, healthy subjects. Dyslexic children showed delayed VEPs to both achromatic stimuli (magnocellular-dorsal stream) and isoluminant red/green and blue/yellow stimuli (parvocellular-ventral and koniocellular streams). To our knowledge, this is the first time that a dysfunction of colour vision has been brought to light in an objective way (i.e., by means of electrophysiological methods) in children with DD. These results give rise to speculation concerning the need for a putative approach for promoting both learning how to read and/or improving existing reading skills of children with or at risk of DD. The working hypothesis would be to combine two integrated interventions in a single programme aimed at fostering the function of both the magnocellular and the parvocellular streams.

Decoding Dyslexia, a Common Learning Disability | NIH MedlinePlus the Magazine

MedlinePlus

... JavaScript on. Feature: Dyslexia Decoding Dyslexia, a Common Learning Disability Past Issues / Winter 2016 Table of Contents What Are Learning Disabilities? Learning disabilities affect how someone learns to read, ...

Planum Temporale Morphology in Children with Developmental Dyslexia

PubMed Central

Bloom, Juliana Sanchez; Garcia-Barrera, Mauricio A.; Miller, Carlin J.; Miller, Scott R.; Hynd, George W.

2013-01-01

The planum temporale is a highly lateralized cortical region, located within Wernicke’s area, which is thought to be involved in auditory processing, phonological processing, and language. Research has linked abnormal morphology of the planum temporale to developmental dyslexia, although results have varied in large part due to methodological inconsistencies in the literature. This study examined the asymmetry of the planum temporale in 29 children who met criteria for dyslexia and 26 children whose reading was unimpaired. Leftward asymmetry of the planum temporale was found in the total sample and this leftward asymmetry was significantly reduced in children with dyslexia. This reduced leftward asymmetry in children with dyslexia was due to a planum temporale that is larger in the right hemisphere. This study lends support to the idea that planum temporale asymmetry is altered in children with developmental dyslexia. PMID:23707683

Neurogenetics of developmental dyslexia: from genes to behavior through brain neuroimaging and cognitive and sensorial mechanisms

PubMed Central

Mascheretti, S; De Luca, A; Trezzi, V; Peruzzo, D; Nordio, A; Marino, C; Arrigoni, F

2017-01-01

Developmental dyslexia (DD) is a complex neurodevelopmental deficit characterized by impaired reading acquisition, in spite of adequate neurological and sensorial conditions, educational opportunities and normal intelligence. Despite the successful characterization of DD-susceptibility genes, we are far from understanding the molecular etiological pathways underlying the development of reading (dis)ability. By focusing mainly on clinical phenotypes, the molecular genetics approach has yielded mixed results. More optimally reduced measures of functioning, that is, intermediate phenotypes (IPs), represent a target for researching disease-associated genetic variants and for elucidating the underlying mechanisms. Imaging data provide a viable IP for complex neurobehavioral disorders and have been extensively used to investigate both morphological, structural and functional brain abnormalities in DD. Performing joint genetic and neuroimaging studies in humans is an emerging strategy to link DD-candidate genes to the brain structure and function. A limited number of studies has already pursued the imaging–genetics integration in DD. However, the results are still not sufficient to unravel the complexity of the reading circuit due to heterogeneous study design and data processing. Here, we propose an interdisciplinary, multilevel, imaging–genetic approach to disentangle the pathways from genes to behavior. As the presence of putative functional genetic variants has been provided and as genetic associations with specific cognitive/sensorial mechanisms have been reported, new hypothesis-driven imaging–genetic studies must gain momentum. This approach would lead to the optimization of diagnostic criteria and to the early identification of ‘biologically at-risk’ children, supporting the definition of adequate and well-timed prevention strategies and the implementation of novel, specific remediation approach. PMID:28045463

DOD SCHOOLS: Additional Reporting Could Improve Accountability for Academic Achievement of Students with Dyslexia

DTIC Science & Technology

2007-12-01

Representatives DOD SCHOOLS Additional Reporting Could Improve Accountability for Academic Achievement of Students with Dyslexia December...Could Improve Accountability for Academic Achievement of Students with Dyslexia 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6...Students with Dyslexia Highlights of GAO-08-70, a report to the Chairman, Committee on Science and Technology, House of Representatives Many of our

Increased variability of stimulus-driven cortical responses is associated with genetic variability in children with and without dyslexia.

PubMed

Centanni, T M; Pantazis, D; Truong, D T; Gruen, J R; Gabrieli, J D E; Hogan, T P

2018-05-26

Individuals with dyslexia exhibit increased brainstem variability in response to sound. It is unknown as to whether increased variability extends to neocortical regions associated with audition and reading, extends to visual stimuli, and whether increased variability characterizes all children with dyslexia or, instead, a specific subset of children. We evaluated the consistency of stimulus-evoked neural responses in children with (N = 20) or without dyslexia (N = 12) as measured by magnetoencephalography (MEG). Approximately half of the children with dyslexia had significantly higher levels of variability in cortical responses to both auditory and visual stimuli in multiple nodes of the reading network. There was a significant and positive relationship between the number of risk alleles at rs6935076 in the dyslexia-susceptibility gene KIAA0319 and the degree of neural variability in primary auditory cortex across all participants. This gene has been linked with neural variability in rodents and in typical readers. These findings indicate that unstable representations of auditory and visual stimuli in auditory and other reading-related neocortical regions are present in a subset of children with dyslexia and support the link between the gene KIAA0319 and the auditory neural variability across children with or without dyslexia. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

Writing Problems in Developmental Dyslexia: Under-Recognized and Under-Treated2,3

PubMed Central

Berninger, Virginia W.; Nielsen, Kathleen H.; Abbott, Robert D.; Wijsman, Ellen; Raskind, Wendy

2008-01-01

The International Dyslexia Association defines dyslexia as unexpected problems of neurobiological origin in accuracy and rate of oral reading of single real words, single pseudowords, or text or of written spelling. However, prior research has focused more on the reading than the spelling problems of students with dyslexia. A test battery was administered to 122 children who met inclusion criteria for dyslexia and qualified their families for participation in a family genetics study that has been ongoing for over a decade. Their parents completed the same test battery. Although a past structural equation modeling study of typically developing children identified a significant path from handwriting to composition quality, the current structural equation modeling study identified a significant path from spelling to composition for children and their parents with dyslexia. Grapho-motor planning did not contribute uniquely to their composition, showing that writing is not just a motor skill. Students with dyslexia do have a problem in automatic letter writing and naming, which was related to impaired inhibition and verbal fluency, and may explain their spelling problems. Results are discussed in reference to the importance of providing explicit instruction in the phonological, orthographic, and morphological processes of spelling and in composition to students with dyslexia and not only offering accommodation for their writing problems. PMID:18438452

Executive functions in adults with developmental dyslexia.

PubMed

Smith-Spark, James H; Henry, Lucy A; Messer, David J; Edvardsdottir, Elisa; Zięcik, Adam P

2016-01-01

Executive functioning (EF) deficits are well recognized in developmental dyslexia, yet the majority of studies have concerned children rather than adults, ignored the subjective experience of the individual with dyslexia (with regard to their own EFs), and have not followed current theoretical perspectives on EFs. The current study addressed these shortfalls by administering a self-report measure of EF (BRIEF-A; Roth, Isquith, & Gioia, 2005) and experimental tasks to IQ-matched groups of adults with and without dyslexia. The laboratory-based tasks tested the three factors constituting the framework of EF proposed by Miyake et al. (2000). In comparison to the group without dyslexia, the participants with dyslexia self-reported more frequent EF problems in day-to-day life, with these difficulties centering on metacognitive processes (working memory, planning, task monitoring, and organization) rather than on the regulation of emotion and behaviour. The participants with dyslexia showed significant deficits in EF (inhibition, set shifting, and working memory). The findings indicated that dyslexia-related problems have an impact on the daily experience of adults with the condition. Further, EF difficulties are present in adulthood across a range of laboratory-based measures, and, given the nature of the experimental tasks presented, extend beyond difficulties related solely to phonological processing. Copyright © 2016 Elsevier Ltd. All rights reserved.

Dyslexia and dyscalculia: two learning disorders with different cognitive profiles.

PubMed

Landerl, Karin; Fussenegger, Barbara; Moll, Kristina; Willburger, Edith

2009-07-01

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 dyslexic/dyscalculic), phonological awareness, phonological and visual-spatial short-term and working memory, naming speed, and basic number processing skills were assessed. A phonological deficit was found for both dyslexic groups, irrespective of additional arithmetic deficits, but not for the dyscalculia-only group. In contrast, deficits in processing of symbolic and nonsymbolic magnitudes were observed in both groups of dyscalculic children, irrespective of additional reading difficulties, but not in the dyslexia-only group. Cognitive deficits in the comorbid dyslexia/dyscalculia group were additive; that is, they resulted from the combination of two learning disorders. These findings suggest that dyslexia and dyscalculia have separable cognitive profiles, namely a phonological deficit in the case of dyslexia and a deficient number module in the case of dyscalculia.

The Joint Effects of Risk Status, Gender, Early Literacy and Cognitive Skills on the Presence of Dyslexia among a Group of High-Risk Chinese Children

ERIC Educational Resources Information Center

Wong, Simpson W. L.; McBride-Chang, Catherine; Lam, Catherine; Chan, Becky; Lam, Fanny W. F.; Doo, Sylvia

2012-01-01

This study sought to examine factors that are predictive of future developmental dyslexia among a group of 5-year-old Chinese children at risk for dyslexia, including 62 children with a sibling who had been previously diagnosed with dyslexia and 52 children who manifested clinical at-risk factors in aspects of language according to testing by…

[Clinical diagnosis of dyslexia].

PubMed

Martínez Hermosillo, A; Balderas Gil, A

1980-01-01

In 5 years of experience at the Instituto Nacional de la Comunicacion Humana, 302 clinical histories showed the diagnosis of dyslexia. The following parameters were studied: age, sex, heredofamilial history, gestation, psychomotor development, clinical picture, examination of the language (type, reading, spontaneous writing, dictation, mathematic concepts), laterality, scholarship, scholar failures, psychological study. The following results were obtained: Dyslexia was more important or frequent between 5 to 8.9 years of age. Males predominated 3:1. The heredofamilial history was important. Dyslexia prevailed in products of the first gestations. A high disturbance was found in the psychomotor development of a large percent of dyslexic patients. Examination of language was also important. Dyslexia was more frequent in right-handed patients. Scholar failures in one or more instances were found. The psychological study must be done. If dyslexia is diagnosed on time, it may be prevented and all unwanted sequelae may be avoided.

University Students with Dyslexia: A Qualitative Exploratory Study of Learning Practices, Challenges and Strategies.

PubMed

MacCullagh, Lois; Bosanquet, Agnes; Badcock, Nicholas A

2017-02-01

People with dyslexia are vastly under-represented in universities (Katusic et al., , Richardson & Wydell, ; Stampoltzis & Polychronopoulou, ). This situation is of concern for modern societies that value social justice. This study was designed to explore learning experiences of university students with dyslexia and factors that could contribute to their success. Thirteen students with dyslexia and 20 non-dyslexic peers were interviewed about their university learning experiences using a semi-structured qualitative approach. Students with dyslexia described engaging in learning activities intensively, frequently and strategically. They reported challenges and strengths relating to study skills, lectures, assessments, technology and support services. They also described helpful strategies including self-directed adaptive techniques, provisions from lecturers and assistance from the university. These findings suggest that students with dyslexia experience broad challenges at university, but helpful strategies may be available. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Neural processing of amplitude and formant rise time in dyslexia.

PubMed

Peter, Varghese; Kalashnikova, Marina; Burnham, Denis

2016-06-01

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. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Spelling in adolescents with dyslexia: errors and modes of assessment.

PubMed

Tops, Wim; Callens, Maaike; Bijn, Evi; Brysbaert, Marc

2014-01-01

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. Three main error categories were distinguished: phonological, orthographic, and grammatical errors (on the basis of morphology and language-specific spelling rules). The results indicated that higher-education students with dyslexia made on average twice as many spelling errors as the controls, with effect sizes of d ≥ 2. When the errors were classified as phonological, orthographic, or grammatical, we found a slight dominance of phonological errors in students with dyslexia. Sentence dictation did not provide more information than word dictation in the correct classification of students with and without dyslexia. © Hammill Institute on Disabilities 2012.

Social dysfunction after pediatric traumatic brain injury: a translational perspective

PubMed Central

Ryan, Nicholas P.; Catroppa, Cathy; Godfrey, Celia; Noble-Haeusslein, Linda J.; Shultz, Sandy R.; O'Brien, Terence J.; Anderson, Vicki; Semple, Bridgette D.

2016-01-01

Social dysfunction is common after traumatic brain injury (TBI), contributing to reduced quality of life for survivors. Factors which influence the emergence, development or persistence of social deficits after injury remain poorly understood, particularly in the context of ongoing brain maturation during childhood. Aberrant social interactions have recently been modeled in adult and juvenile rodents after experimental TBI, providing an opportunity to gain new insights into the underlying neurobiology of these behaviors. Here, we review our current understanding of social dysfunction in both humans and rodent models of TBI, with a focus on brain injuries acquired during early development. Modulators of social outcomes are discussed, including injury-related and environmental risk and resilience factors. Disruption of social brain network connectivity and aberrant neuroendocrine function are identified as potential mechanisms of social impairments after pediatric TBI. Throughout, we highlight the overlap and disparities between outcome measures and findings from clinical and experimental approaches, and explore the translational potential of future research to prevent or ameliorate social dysfunction after childhood TBI. PMID:26949224

[5-year course of dyslexia – Persistence, sex effects, performance in reading and spelling, and school-related success].

PubMed

Wyschkon, Anne; Schulz, Franziska; Gallit, Finja Sunnyi; Poltz, Nadine; Kohn, Juliane; Moraske, Svenja; Bondü, Rebecca; von Aster, Michael; Esser, Günter

2018-03-01

The study examines the 5-year course of children with dyslexia with regard to their sex. Furthermore, the study investigates the impact of dyslexia on the performance in reading and spelling skills and school-related success. A group of 995 6- to 16-year-olds were examined at the initial assessment. Part of the initial sample was then re-examined after 43 and 63 months. The diagnosis of dyslexia was based on the double discrepancy criterion using a standard deviation of 1.5. Though they had no intellectual deficits, the children showed a considerable discrepancy between their reading or writing abilities and (1) their nonverbal intelligence and (2) the mean of their grade norm. Nearly 70 % of those examined had a persisting diagnosis of dyslexia over a period of 63 months. The 5-year course was not influenced by sex. Despite average intelligence, the performance in writing and spelling of children suffering from dyslexia was one standard deviation below a control group without dyslexia with average intelligence and 0.5 standard deviations below a group of children suffering from intellectual deficits. Furthermore, the school-related success of the dyslexics was significantly lower than those of children with average intelligence. Dyslexics showed similar school-related success rates to children suffering from intellectual deficits. Dyslexia represents a considerable developmental risk. The adverse impact of dyslexia on school-related success supports the importance of early diagnostics and intervention. It also underlines the need for reliable and general accepted diagnostic criteria. It is important to define such criteria in light of the prevalence rates.

A virtual reality test identifies the visuospatial strengths of adolescents with dyslexia.

PubMed

Attree, Elizabeth A; Turner, Mark J; Cowell, Naina

2009-04-01

Research suggests that the deficits characterizing dyslexia may also be associated with superior visuospatial abilities. Other research suggests that superior visuospatial abilities of people with dyslexia may not have been so far identified because of the lack of appropriate tests of real-life spatial ability. A recent small-scale study found that visuospatial superiority was evident in men with dyslexia. This study assessed the visuospatial ability of adolescents with dyslexia in order to determine whether these adolescents performed better on a pseudo real-life visuospatial test than did their nondyslexic peers. Forty-two adolescents took part in the study. There was an equal numerical split between the experimental and control groups. The experimental group all had a diagnosis of dyslexia by an educational psychologist or specialist teacher. Visuospatial ability was assessed using the Recall of Designs and the Pattern Construction subtests from the British Ability Scales (2nd edition; BAS-11) together with a computer-generated virtual environment test. The assessments were administered in a counterbalanced order. Adolescents with dyslexia tended to perform less well than their nondyslexic peers on the BAS-11 tests; however, this difference was not statistically significant. For the computer-generated virtual environment test (pseudo real-life measure), statistically significant higher scores were achieved by the dyslexic group. These findings suggest that adolescents with dyslexia may exhibit superior visuospatial strengths on certain pseudo real-life tests of spatial ability. The usefulness of these findings is discussed in relation to possible implications for assessment and educational intervention programs for adolescents with dyslexia.

Race and Dyslexia

ERIC Educational Resources Information Center

Hoyles, Asher; Hoyles, Martin

2010-01-01

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…

RADAR: A novel fast-screening method for reading difficulties with special focus on dyslexia.

PubMed

Smyrnakis, Ioannis; Andreadakis, Vassilios; Selimis, Vassilios; Kalaitzakis, Michail; Bachourou, Theodora; Kaloutsakis, Georgios; Kymionis, George D; Smirnakis, Stelios; Aslanides, Ioannis M

2017-01-01

Dyslexia is a developmental learning disorder of single word reading accuracy and/or fluency, with compelling research directed towards understanding the contributions of the visual system. While dyslexia is not an oculomotor disease, readers with dyslexia have shown different eye movements than typically developing students during text reading. Readers with dyslexia exhibit longer and more frequent fixations, shorter saccade lengths, more backward refixations than typical readers. Furthermore, readers with dyslexia are known to have difficulty in reading long words, lower skipping rate of short words, and high gaze duration on many words. It is an open question whether it is possible to harness these distinctive oculomotor scanning patterns observed during reading in order to develop a screening tool that can reliably identify struggling readers, who may be candidates for dyslexia. Here, we introduce a novel, fast, objective, non-invasive method, named Rapid Assessment of Difficulties and Abnormalities in Reading (RADAR) that screens for features associated with the aberrant visual scanning of reading text seen in dyslexia. Eye tracking parameter measurements that are stable under retest and have high discriminative power, as indicated by their ROC (receiver operating characteristic) curves, were obtained during silent text reading. These parameters were combined to derive a total reading score (TRS) that can reliably separate readers with dyslexia from typical readers. We tested TRS in a group of school-age children ranging from 8.5 to 12.5 years of age. TRS achieved 94.2% correct classification of children tested. Specifically, 35 out of 37 control (specificity 94.6%) and 30 out of 32 readers with dyslexia (sensitivity 93.8%) were classified correctly using RADAR, under a circular validation condition (see section Results/Total Reading Score) where the individual evaluated was not included in the test construction group. In conclusion, RADAR is a novel, automated, fast and reliable way to identify children at high risk of dyslexia that is amenable to large-scale screening. Moreover, analysis of eye movement parameters obtained with RADAR during reading will likely be useful for implementing individualized treatment strategies and for monitoring objectively the success of chosen interventions. We envision that it will be possible to use RADAR as a sensitive, objective, and quantitative first pass screen to identify individuals with reading disorders that manifest with abnormal oculomotor reading strategies, like dyslexia.

RADAR: A novel fast-screening method for reading difficulties with special focus on dyslexia

PubMed Central

Smyrnakis, Ioannis; Andreadakis, Vassilios; Selimis, Vassilios; Kalaitzakis, Michail; Bachourou, Theodora; Kaloutsakis, Georgios; Kymionis, George D.; Smirnakis, Stelios; Aslanides, Ioannis M.

2017-01-01

Dyslexia is a developmental learning disorder of single word reading accuracy and/or fluency, with compelling research directed towards understanding the contributions of the visual system. While dyslexia is not an oculomotor disease, readers with dyslexia have shown different eye movements than typically developing students during text reading. Readers with dyslexia exhibit longer and more frequent fixations, shorter saccade lengths, more backward refixations than typical readers. Furthermore, readers with dyslexia are known to have difficulty in reading long words, lower skipping rate of short words, and high gaze duration on many words. It is an open question whether it is possible to harness these distinctive oculomotor scanning patterns observed during reading in order to develop a screening tool that can reliably identify struggling readers, who may be candidates for dyslexia. Here, we introduce a novel, fast, objective, non-invasive method, named Rapid Assessment of Difficulties and Abnormalities in Reading (RADAR) that screens for features associated with the aberrant visual scanning of reading text seen in dyslexia. Eye tracking parameter measurements that are stable under retest and have high discriminative power, as indicated by their ROC (receiver operating characteristic) curves, were obtained during silent text reading. These parameters were combined to derive a total reading score (TRS) that can reliably separate readers with dyslexia from typical readers. We tested TRS in a group of school-age children ranging from 8.5 to 12.5 years of age. TRS achieved 94.2% correct classification of children tested. Specifically, 35 out of 37 control (specificity 94.6%) and 30 out of 32 readers with dyslexia (sensitivity 93.8%) were classified correctly using RADAR, under a circular validation condition (see section Results/Total Reading Score) where the individual evaluated was not included in the test construction group. In conclusion, RADAR is a novel, automated, fast and reliable way to identify children at high risk of dyslexia that is amenable to large-scale screening. Moreover, analysis of eye movement parameters obtained with RADAR during reading will likely be useful for implementing individualized treatment strategies and for monitoring objectively the success of chosen interventions. We envision that it will be possible to use RADAR as a sensitive, objective, and quantitative first pass screen to identify individuals with reading disorders that manifest with abnormal oculomotor reading strategies, like dyslexia. PMID:28800632

Acute transient cognitive dysfunction and acute brain injury induced by systemic inflammation occur by dissociable IL-1-dependent mechanisms.

PubMed

Skelly, Donal T; Griffin, Éadaoin W; Murray, Carol L; Harney, Sarah; O'Boyle, Conor; Hennessy, Edel; Dansereau, Marc-Andre; Nazmi, Arshed; Tortorelli, Lucas; Rawlins, J Nicholas; Bannerman, David M; Cunningham, Colm

2018-06-06

Systemic inflammation can impair cognition with relevance to dementia, delirium and post-operative cognitive dysfunction. Episodes of delirium also contribute to rates of long-term cognitive decline, implying that these acute events induce injury. Whether systemic inflammation-induced acute dysfunction and acute brain injury occur by overlapping or discrete mechanisms remains unexplored. Here we show that systemic inflammation, induced by bacterial LPS, produces both working-memory deficits and acute brain injury in the degenerating brain and that these occur by dissociable IL-1-dependent processes. In normal C57BL/6 mice, LPS (100 µg/kg) did not affect working memory but impaired long-term memory consoliodation. However prior hippocampal synaptic loss left mice selectively vulnerable to LPS-induced working memory deficits. Systemically administered IL-1 receptor antagonist (IL-1RA) was protective against, and systemic IL-1β replicated, these working memory deficits. Dexamethasone abolished systemic cytokine synthesis and was protective against working memory deficits, without blocking brain IL-1β synthesis. Direct application of IL-1β to ex vivo hippocampal slices induced non-synaptic depolarisation and irrevesible loss of membrane potential in CA1 neurons from diseased animals and systemic LPS increased apoptosis in the degenerating brain, in an IL-1RI -/- -dependent fashion. The data suggest that LPS induces working memory dysfunction via circulating IL-1β but direct hippocampal action of IL-1β causes neuronal dysfunction and may drive neuronal death. The data suggest that acute systemic inflammation produces both reversible cognitive deficits, resembling delirium, and acute brain injury contributing to long-term cognitive impairment but that these events are mechanistically dissociable. These data have significant implications for management of cognitive dysfunction during acute illness.

Mothers speak differently to infants at-risk for dyslexia.

PubMed

Kalashnikova, Marina; Goswami, Usha; Burnham, Denis

2018-01-01

Dyslexia is a neurodevelopmental disorder manifested in deficits in reading and spelling skills that is consistently associated with difficulties in phonological processing. Dyslexia is genetically transmitted, but its manifestation in a particular individual is thought to depend on the interaction of epigenetic and environmental factors. We adopt a novel interactional perspective on early linguistic environment and dyslexia by simultaneously studying two pre-existing factors, one maternal and one infant, that may contribute to these interactions; and two behaviours, one maternal and one infant, to index the effect of these factors. The maternal factor is whether mothers are themselves dyslexic or not (with/without dyslexia) and the infant factor is whether infants are at-/not-at family risk for dyslexia (due to their mother or father being dyslexic). The maternal behaviour is mothers' infant-directed speech (IDS), which typically involves vowel hyperarticulation, thought to benefit speech perception and language acquisition. The infant behaviour is auditory perception measured by infant sensitivity to amplitude envelope rise time, which has been found to be reduced in dyslexic children. Here, at-risk infants showed significantly poorer acoustic sensitivity than not-at-risk infants and mothers only hyperarticulated vowels to infants who were not at-risk for dyslexia. Mothers' own dyslexia status had no effect on IDS quality. Parental speech input is thus affected by infant risk status, with likely consequences for later linguistic development. © 2016 John Wiley & Sons Ltd.

Phonological deficits in specific language impairment and developmental dyslexia: towards a multidimensional model

PubMed Central

Ramus, Franck; Marshall, Chloe R.; Rosen, Stuart

2013-01-01

An on-going debate surrounds the relationship between specific language impairment and developmental dyslexia, in particular with respect to their phonological abilities. Are these distinct disorders? To what extent do they overlap? Which cognitive and linguistic profiles correspond to specific language impairment, dyslexia and comorbid cases? At least three different models have been proposed: the severity model, the additional deficit model and the component model. We address this issue by comparing children with specific language impairment only, those with dyslexia-only, those with specific language impairment and dyslexia and those with no impairment, using a broad test battery of language skills. We find that specific language impairment and dyslexia do not always co-occur, and that some children with specific language impairment do not have a phonological deficit. Using factor analysis, we find that language abilities across the four groups of children have at least three independent sources of variance: one for non-phonological language skills and two for distinct sets of phonological abilities (which we term phonological skills versus phonological representations). Furthermore, children with specific language impairment and dyslexia show partly distinct profiles of phonological deficit along these two dimensions. We conclude that a multiple-component model of language abilities best explains the relationship between specific language impairment and dyslexia and the different profiles of impairment that are observed. PMID:23413264

A new self-report inventory of dyslexia for students: criterion and construct validity.

PubMed

Tamboer, Peter; Vorst, Harrie C M

2015-02-01

The validity of a Dutch self-report inventory of dyslexia was ascertained in two samples of students. Six biographical questions, 20 general language statements and 56 specific language statements were based on dyslexia as a multi-dimensional deficit. Dyslexia and non-dyslexia were assessed with two criteria: identification with test results (Sample 1) and classification using biographical information (both samples). Using discriminant analyses, these criteria were predicted with various groups of statements. All together, 11 discriminant functions were used to estimate classification accuracy of the inventory. In Sample 1, 15 statements predicted the test criterion with classification accuracy of 98%, and 18 statements predicted the biographical criterion with classification accuracy of 97%. In Sample 2, 16 statements predicted the biographical criterion with classification accuracy of 94%. Estimations of positive and negative predictive value were 89% and 99%. Items of various discriminant functions were factor analysed to find characteristic difficulties of students with dyslexia, resulting in a five-factor structure in Sample 1 and a four-factor structure in Sample 2. Answer bias was investigated with measures of internal consistency reliability. Less than 20 self-report items are sufficient to accurately classify students with and without dyslexia. This supports the usefulness of self-assessment of dyslexia as a valid alternative to diagnostic test batteries. Copyright © 2015 John Wiley & Sons, Ltd.

Pinpointing the deficit in executive functions in adolescents with dyslexia performing the Wisconsin card sorting test: an ERP study.

PubMed

Horowitz-Kraus, Tzipi

2014-01-01

Adolescents with dyslexia exhibit well-established impairments in executive abilities. The Wisconsin card sorting test (WCST) is an executive test that yields surprisingly inconsistent results with this population. The current study aimed to shed light on the contradictory findings in the literature regarding the performance levels by individuals with dyslexia in WCST. We used a computerized-WCST (named the 'Madrid-Card Sorting Test') assessing executive functions using the Event-Related Potentials (ERPs) methodology. Adolescents with dyslexia exhibited a higher error rate and slower reaction times. This was most evident in the later trials of the series. However, differences in ERPs between the two groups were found only in the "target-locked" conditions, where individuals with dyslexia displayed decreased ERP components (N100, P300) compared to skilled readers. The changes between the groups in the "shift" compared to the "stay" conditions suggest the central role of working memory both in basic (e.g., shifting) and higher order (e.g., reading) processes in individuals with dyslexia. These findings suggest the central role of working memory both in basic (e.g., shifting) and higher order (e.g., reading) processes in individuals with dyslexia. The intact shifting mechanism and the working memory deficit may guide the building of more efficient intervention programs for individuals with dyslexia in the future.

Self-Reports of Increased Prospective and Retrospective Memory Problems in Adults with Developmental Dyslexia.

PubMed

Smith-Spark, James H; Zięcik, Adam P; Sterling, Christopher

2016-08-01

Short-term and working memory problems in dyslexia are well-documented, but other memory domains have received little empirical scrutiny, despite some evidence to suggest that they might be impaired. Prospective memory is memory for delayed intentions, whilst retrospective memory relates to memory for personally experienced past events. To gain an understanding of subjective everyday memory experience, a self-report measure designed to tap prospective and retrospective memory was administered to 28 adults with dyslexia and 26 IQ-matched adults without dyslexia. Adults with dyslexia reported experiencing significantly more frequent problems with memory than the adults without dyslexia. Group differences were found across seven out of the eight questionnaire scales. Further to these analyses, the participants' own ratings were compared with proxy ratings provided by close associates. The perception of poorer memory abilities in the participants did not differ between respondent types. The self-reported difficulties are, thus, unlikely to be the result of lowered self-esteem or metacognitive awareness. More frequent difficulties with both types of memory would seem, therefore, to be experienced by adults with dyslexia in everyday life. Further laboratory-based research is recommended to explore both memory domains in dyslexia and to identify the cognitive mechanisms by which these problems occur. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Reading accuracy and speed of vowelized and unvowelized scripts among dyslexic readers of Hebrew: the road not taken.

PubMed

Schiff, Rachel; Katzir, Tami; Shoshan, Noa

2013-07-01

The present study examined the effects of orthographic transparency on reading ability of children with dyslexia in two Hebrew scripts. The study explored the reading accuracy and speed of vowelized and unvowelized Hebrew words of fourth-grade children with dyslexia. A comparison was made to typically developing readers of two age groups: a group matched by chronological age and a group of children who are 2 years younger, presumably at the end of the reading acquisition process. An additional purpose was to investigate the role of vowelization in the reading ability of unvowelized script among readers with dyslexia in an attempt to assess whether vowelization plays a mediating role for reading speed of unvowelized scripts. The present study found no significant differences in reading accuracy and speed between vowelized and unvowelized scripts among fourth-grade readers with dyslexia. The reading speed of fourth-graders with dyslexia was similar to typically developing second-graders for both the vowelized and unvowelized words. However, fourth-grade children with dyslexia performed lower than the typically developing second-graders in the reading accuracy of vowelized script. Furthermore, for readers with dyslexia, accuracy in reading both vowelized and unvowelized words mediated the reading speed of unvowelized scripts. These results may be a sign that Hebrew-speaking children with dyslexia have severe difficulties that prevent them from developing strategies for more efficient reading.

Speech Recognition in Noise by Children with and without Dyslexia: How is it Related to Reading?

PubMed

Nittrouer, Susan; Krieg, Letitia M; Lowenstein, Joanna H

2018-06-01

Developmental dyslexia is commonly viewed as a phonological deficit that makes it difficult to decode written language. But children with dyslexia typically exhibit other problems, as well, including poor speech recognition in noise. The purpose of this study was to examine whether the speech-in-noise problems of children with dyslexia are related to their reading problems, and if so, if a common underlying factor might explain both. The specific hypothesis examined was that a spectral processing disorder results in these children receiving smeared signals, which could explain both the diminished sensitivity to phonological structure - leading to reading problems - and the speech recognition in noise difficulties. The alternative hypothesis tested in this study was that children with dyslexia simply have broadly based language deficits. Ninety-seven children between the ages of 7 years; 10 months and 12 years; 9 months participated: 46 with dyslexia and 51 without dyslexia. Children were tested on two dependent measures: word reading and recognition in noise with two types of sentence materials: as unprocessed (UP) signals, and as spectrally smeared (SM) signals. Data were collected for four predictor variables: phonological awareness, vocabulary, grammatical knowledge, and digit span. Children with dyslexia showed deficits on both dependent and all predictor variables. Their scores for speech recognition in noise were poorer than those of children without dyslexia for both the UP and SM signals, but by equivalent amounts across signal conditions indicating that they were not disproportionately hindered by spectral distortion. Correlation analyses on scores from children with dyslexia showed that reading ability and speech-in-noise recognition were only mildly correlated, and each skill was related to different underlying abilities. No substantial evidence was found to support the suggestion that the reading and speech recognition in noise problems of children with dyslexia arise from a single factor that could be defined as a spectral processing disorder. The reading and speech recognition in noise deficits of these children appeared to be largely independent. Copyright © 2018 Elsevier Ltd. All rights reserved.

Dyslexic children lack word selectivity gradients in occipito-temporal and inferior frontal cortex.

PubMed

Olulade, O A; Flowers, D L; Napoliello, E M; Eden, G F

2015-01-01

fMRI studies using a region-of-interest approach have revealed that the ventral portion of the left occipito-temporal cortex, which is specialized for orthographic processing of visually presented words (and includes the so-called "visual word form area", VWFA), is characterized by a posterior-to-anterior gradient of increasing selectivity for words in typically reading adults, adolescents, and children (e.g. Brem et al., 2006, 2009). Similarly, the left inferior frontal cortex (IFC) has been shown to exhibit a medial-to-lateral gradient of print selectivity in typically reading adults (Vinckier et al., 2007). Functional brain imaging studies of dyslexia have reported relative underactivity in left hemisphere occipito-temporal and inferior frontal regions using whole-brain analyses during word processing tasks. Hence, the question arises whether gradient sensitivities in these regions are altered in dyslexia. Indeed, a region-of-interest analysis revealed the gradient-specific functional specialization in the occipito-temporal cortex to be disrupted in dyslexic children (van der Mark et al., 2009). Building on these studies, we here (1) investigate if a word-selective gradient exists in the inferior frontal cortex in addition to the occipito-temporal cortex in normally reading children, (2) compare typically reading with dyslexic children, and (3) examine functional connections between these regions in both groups. We replicated the previously reported anterior-to-posterior gradient of increasing selectivity for words in the left occipito-temporal cortex in typically reading children, and its absence in the dyslexic children. Our novel finding is the detection of a pattern of increasing selectivity for words along the medial-to-lateral axis of the left inferior frontal cortex in typically reading children and evidence of functional connectivity between the most lateral aspect of this area and the anterior aspects of the occipito-temporal cortex. We report absence of an IFC gradient and connectivity between the lateral aspect of the IFC and the anterior occipito-temporal cortex in the dyslexic children. Together, our results provide insights into the source of the anomalies reported in previous studies of dyslexia and add to the growing evidence of an orthographic role of IFC in reading.

Primary Cilia as a Possible Link between Left-Right Asymmetry and Neurodevelopmental Diseases.

PubMed

Trulioff, Andrey; Ermakov, Alexander; Malashichev, Yegor

2017-01-25

Cilia have multiple functions in the development of the entire organism, and participate in the development and functioning of the central nervous system. In the last decade, studies have shown that they are implicated in the development of the visceral left-right asymmetry in different vertebrates. At the same time, some neuropsychiatric disorders, such as schizophrenia, autism, bipolar disorder, and dyslexia, are known to be associated with lateralization failure. In this review, we consider possible links in the mechanisms of determination of visceral asymmetry and brain lateralization, through cilia. We review the functions of seven genes associated with both cilia, and with neurodevelopmental diseases, keeping in mind their possible role in the establishment of the left-right brain asymmetry.

Primary Cilia as a Possible Link between Left-Right Asymmetry and Neurodevelopmental Diseases

PubMed Central

Trulioff, Andrey; Ermakov, Alexander; Malashichev, Yegor

2017-01-01

Cilia have multiple functions in the development of the entire organism, and participate in the development and functioning of the central nervous system. In the last decade, studies have shown that they are implicated in the development of the visceral left-right asymmetry in different vertebrates. At the same time, some neuropsychiatric disorders, such as schizophrenia, autism, bipolar disorder, and dyslexia, are known to be associated with lateralization failure. In this review, we consider possible links in the mechanisms of determination of visceral asymmetry and brain lateralization, through cilia. We review the functions of seven genes associated with both cilia, and with neurodevelopmental diseases, keeping in mind their possible role in the establishment of the left-right brain asymmetry. PMID:28125008

Global loss of acetylcholinesterase activity with mitochondrial complexes inhibition and inflammation in brain of hypercholesterolemic mice.

PubMed

Paul, Rajib; Borah, Anupom

2017-12-20

There exists an intricate relationship between hypercholesterolemia (elevated plasma cholesterol) and brain functions. The present study aims to understand the impact of hypercholesterolemia on pathological consequences in mouse brain. A chronic mouse model of hypercholesterolemia was induced by giving high-cholesterol diet for 12 weeks. The hypercholesterolemic mice developed cognitive impairment as evident from object recognition memory test. Cholesterol accumulation was observed in four discrete brain regions, such as cortex, striatum, hippocampus and substantia nigra along with significantly damaged blood-brain barrier by hypercholesterolemia. The crucial finding is the loss of acetylcholinesterase activity with mitochondrial dysfunction globally in the brain of hypercholesterolemic mice, which is related to the levels of cholesterol. Moreover, the levels of hydroxyl radical were elevated in the regions of brain where the activity of mitochondrial complexes was found to be reduced. Intriguingly, elevations of inflammatory stress markers in the cholesterol-rich brain regions were observed. As cognitive impairment, diminished brain acetylcholinesterase activity, mitochondrial dysfunctions, and inflammation are the prima facie pathologies of neurodegenerative diseases, the findings impose hypercholesterolemia as potential risk factor towards brain dysfunction.

The Role of Categorical Speech Perception and Phonological Processing in Familial Risk Children With and Without Dyslexia.

PubMed

Hakvoort, Britt; de Bree, Elise; van der Leij, Aryan; Maassen, Ben; van Setten, Ellie; Maurits, Natasha; van Zuijen, Titia L

2016-12-01

This study assessed whether a categorical speech perception (CP) deficit is associated with dyslexia or familial risk for dyslexia, by exploring a possible cascading relation from speech perception to phonology to reading and by identifying whether speech perception distinguishes familial risk (FR) children with dyslexia (FRD) from those without dyslexia (FRND). Data were collected from 9-year-old FRD (n = 37) and FRND (n = 41) children and age-matched controls (n = 49) on CP identification and discrimination and on the phonological processing measures rapid automatized naming, phoneme awareness, and nonword repetition. The FRD group performed more poorly on CP than the FRND and control groups. Findings on phonological processing align with the literature in that (a) phonological processing related to reading and (b) the FRD group showed the lowest phonological processing outcomes. Furthermore, CP correlated weakly with reading, but this relationship was fully mediated by rapid automatized naming. Although CP phonological skills are related to dyslexia, there was no strong evidence for a cascade from CP to phonology to reading. Deficits in CP at the behavioral level are not directly associated with dyslexia.

Investigating speech perception in children with dyslexia: is there evidence of a consistent deficit in individuals?

PubMed Central

Messaoud-Galusi, Souhila; Hazan, Valerie; Rosen, Stuart

2012-01-01

Purpose The claim that speech perception abilities are impaired in dyslexia was investigated in a group of 62 dyslexic children and 51 average readers matched in age. Method To test whether there was robust evidence of speech perception deficits in children with dyslexia, speech perception in noise and quiet was measured using eight different tasks involving the identification and discrimination of a complex and highly natural synthetic ‘pea’-‘bee’ contrast (copy synthesised from natural models) and the perception of naturally-produced words. Results Children with dyslexia, on average, performed more poorly than average readers in the synthetic syllables identification task in quiet and in across-category discrimination (but not when tested using an adaptive procedure). They did not differ from average readers on two tasks of word recognition in noise or identification of synthetic syllables in noise. For all tasks, a majority of individual children with dyslexia performed within norms. Finally, speech perception generally did not correlate with pseudo-word reading or phonological processing, the core skills related to dyslexia. Conclusions On the tasks and speech stimuli we used, most children with dyslexia do not appear to show a consistent deficit in speech perception. PMID:21930615

Neural encoding of the speech envelope by children with developmental dyslexia.

PubMed

Power, Alan J; Colling, Lincoln J; Mead, Natasha; Barnes, Lisa; Goswami, Usha

2016-09-01

Developmental dyslexia is consistently associated with difficulties in processing phonology (linguistic sound structure) across languages. One view is that dyslexia is characterised by a cognitive impairment in the "phonological representation" of word forms, which arises long before the child presents with a reading problem. Here we investigate a possible neural basis for developmental phonological impairments. We assess the neural quality of speech encoding in children with dyslexia by measuring the accuracy of low-frequency speech envelope encoding using EEG. We tested children with dyslexia and chronological age-matched (CA) and reading-level matched (RL) younger children. Participants listened to semantically-unpredictable sentences in a word report task. The sentences were noise-vocoded to increase reliance on envelope cues. Envelope reconstruction for envelopes between 0 and 10Hz showed that the children with dyslexia had significantly poorer speech encoding in the 0-2Hz band compared to both CA and RL controls. These data suggest that impaired neural encoding of low frequency speech envelopes, related to speech prosody, may underpin the phonological deficit that causes dyslexia across languages. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

A General Audiovisual Temporal Processing Deficit in Adult Readers With Dyslexia.

PubMed

Francisco, Ana A; Jesse, Alexandra; Groen, Margriet A; McQueen, James M

2017-01-01

Because reading is an audiovisual process, reading impairment may reflect an audiovisual processing deficit. The aim of the present study was to test the existence and scope of such a deficit in adult readers with dyslexia. We tested 39 typical readers and 51 adult readers with dyslexia on their sensitivity to the simultaneity of audiovisual speech and nonspeech stimuli, their time window of audiovisual integration for speech (using incongruent /aCa/ syllables), and their audiovisual perception of phonetic categories. Adult readers with dyslexia showed less sensitivity to audiovisual simultaneity than typical readers for both speech and nonspeech events. We found no differences between readers with dyslexia and typical readers in the temporal window of integration for audiovisual speech or in the audiovisual perception of phonetic categories. The results suggest an audiovisual temporal deficit in dyslexia that is not specific to speech-related events. But the differences found for audiovisual temporal sensitivity did not translate into a deficit in audiovisual speech perception. Hence, there seems to be a hiatus between simultaneity judgment and perception, suggesting a multisensory system that uses different mechanisms across tasks. Alternatively, it is possible that the audiovisual deficit in dyslexia is only observable when explicit judgments about audiovisual simultaneity are required.

The Nature of Verbal Short-Term Impairment in Dyslexia: The Importance of Serial Order

PubMed Central

Majerus, Steve; Cowan, Nelson

2016-01-01

Verbal short-term memory (STM) impairment is one of the most consistent associated deficits observed in developmental reading disorders such as dyslexia. Few studies have addressed the nature of this STM impairment, especially as regards the ability to temporarily store serial order information. This question is important as studies in typically developing children have shown that serial order STM abilities are predictors of oral and written language development. Associated serial order STM deficits in dyslexia may therefore further increase the learning difficulties in these populations. In this mini review, we show that specific serial order STM impairment is frequently reported in both dyslexic children and adults with a history of dyslexia. Serial order STM impairment appears to occur for the retention of both verbal and visuo-spatial sequence information. Serial order STM impairment is, however, not a characteristic of every individual dyslexic subject and is not specific to dyslexia. Future studies need to determine whether serial order STM impairment is a risk factor which, in association with phonological processing deficits, can lead to dyslexia or whether serial order STM impairment reflects associated deficits causally unrelated to dyslexia. PMID:27752247

Learner-generated drawing for phonological and orthographic dyslexic readers.

PubMed

Wang, Li-Chih; Yang, Hsien-Ming; Tasi, Hung-Ju; Chan, Shih-Yi

2013-01-01

This study presents an examination of learner-generated drawing for different reading comprehension subtypes of dyslexic students and control students. The participants were 22 phonological dyslexic students, 20 orthographic dyslexic students, 21 double-deficit dyslexic students, and 45 age-, gender-, and IQ-matched control students. The major evaluation tools included word recognition task, orthographic task, phonological awareness task, and scenery texts and questions. Comparisons of the four groups of students showed differences among phonological dyslexia, orthographic dyslexia, double-deficit dyslexia, and the chronological age control groups in pre- and posttest performance of scenery texts. Differences also existed in relevant questions and the effect of the learner-generated drawing method. The pretest performance showed problems in the dyslexic samples in reading the scenery texts and answering relevant questions. The posttest performance revealed certain differences among phonological dyslexia, orthographic dyslexia, double-deficit dyslexia, and the chronological age control group. Finally, all dyslexic groups obtained a great effect from using the learner-generated drawing, particularly orthographic dyslexia. These results suggest that the learner-generated drawing was also useful for dyslexic students, with the potential for use in the classroom for teaching text reading to dyslexic students. Copyright © 2012 Elsevier Ltd. All rights reserved.

'Speedy action over goal orientation': cognitive impulsivity in male forensic patients with dyslexia.

PubMed

Dåderman, Anna M; Meurling, Ann Wirsén; Levander, Sten

2012-11-01

Previous neuropsychiatric studies suggest a relationship between reading disability and cognitive impulsivity. This relationship is not entirely explained by the high comorbidity between reading disability and attention deficit hyperactivity disorder (ADHD), as children with a co-occurrence of these disorders tend to be more impulsive than those with ADHD only. Other research has demonstrated that poor verbal skill (irrespective of the presence of dyslexia) deficits in executive functions and impulsivity are important risk factors for criminal behaviour. The present study bridges these two research traditions by examining whether patients undergoing forensic psychiatric investigation who also have dyslexia, have a cognitive style characterized by impulsivity. Male forensic patients (mean age 27 years, range 16-35) with (n = 9) and without (n = 13) dyslexia were evaluated on the computerized EuroCog test battery. The findings suggest that patients with dyslexia tend to use a cognitive impulsive style and suggest a more direct link between dyslexia and cognitive impulsivity that is not mediated by the presence of ADHD. In order to identify treatment needs and tailor treatment accordingly, forensic patients should be assessed with respect to poor verbal skill, dyslexia and impulsivity. Copyright © 2012 John Wiley & Sons, Ltd.

Exploring the impact of living with dyslexia: The perspectives of children and their parents.

PubMed

Leitão, Suze; Dzidic, Peta; Claessen, Mary; Gordon, Joanne; Howard, Kate; Nayton, Mandy; Boyes, Mark E

2017-06-01

A small but growing body of literature indicates that children with dyslexia are at elevated risk of internalising and externalising mental health problems. However, little research addresses why this might be the case, particularly from the point of view of the children or their parents. This study therefore aimed to explore the lived experiences of children with dyslexia, and their parents. Drawing on a phenomenological approach, 13 children with dyslexia and 21 parents were interviewed. The semi-structured interviews were analysed thematically. Dyslexia was seen to impact at the individual, family and community level. Children's accounts of their experiences were ecologically situated at both the micro and mesosystem levels of Bronfenbrenner's ecological model, while parent's accounts extended to include the exosystem. Both also reflected on "difference", a theme related to cultural and attitudinal views at the level of the macrosystem. Presentation of the themes contrasts the experiences of children and parents, illustrating that the experience of dyslexia is indicative of broader challenges associated with societal values and attitudes that privilege perceived ability and shame difference. This study provides information that could be used to inform and educate families and teachers about the impact of living with dyslexia.

Predicting dyslexia at age 11 from a risk index questionnaire at age 5.

PubMed

Helland, Turid; Plante, Elena; Hugdahl, Kenneth

2011-08-01

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 questionnaire was given to caretakers of 120 5-year-old children, and a risk index score was calculated based on questions regarding health, laterality, motor skills, language, special needs education and heredity. An at-risk group (n = 25) and matched controls (n = 24) were followed until age 11, when a similar questionnaire and literacy tests were administered to the children who participated in the follow-up study (22 at risk and 20 control). Half of the at-risk children and two of the control children at age 5 were identified as having dyslexia at age 11 (8 girls and 5 boys). It is concluded that it is possible to identify children at the age of 5 who will have dyslexia at the age of 11 through a questionnaire approach. Copyright © 2011 John Wiley & Sons, Ltd.

Reasoning and dyslexia: a spatial strategy may impede reasoning with visually rich information.

PubMed

Bacon, Alison M; Handley, Simon J; McDonald, Emma L

2007-02-01

Bacon, Handley, and Newstead (2003, 2004), have presented evidence for individual differences in reasoning strategies, with most people seeming to represent and manipulate problem information using either a verbal or a spatial strategy. There is also evidence that individuals with dyslexia are inclined to conceptualise information in a visuo-spatial, rather than a verbal, way (e.g. von Károlyi et al., 2003). If so, we might expect a higher proportion of individuals with dyslexia to be spatial reasoners, compared with individuals who do not have dyslexia. The study reported here directly compared strategies reported by these two groups of participants on a syllogistic reasoning task. Moreover, problem content was manipulated so that reasoning across concrete and abstract materials could be compared. The findings suggest that whilst most individuals without dyslexia use a verbal strategy, reasoners with dyslexia do tend to adopt a spatial approach, though their performance is impaired with visually concrete materials. However, when reasoning with more abstract content, they perform comparably with non-dyslexic controls. The paper discusses these results in the light of recent research which has suggested that visual images may impede reasoning, and considers how individuals with dyslexia may differ from other reasoners.

Statistical Learning and Dyslexia: A Systematic Review

ERIC Educational Resources Information Center

Schmalz, Xenia; Altoè, Gianmarco; Mulatti, Claudio

2017-01-01

The existing literature on developmental dyslexia (hereafter: dyslexia) often focuses on isolating cognitive skills which differ across dyslexic and control participants. Among potential correlates, previous research has studied group differences between dyslexic and control participants in performance on statistical learning tasks. A statistical…

[Brainstem auditory evoked potentials in neurophysiological assessment of brain stem dysfunction in patients with atherostenosis of vertebral arteries].

PubMed

Maksimova, M Yu; Sermagambetova, Zh N; Skrylev, S I; Fedin, P A; Koshcheev, A Yu; Shchipakin, V L; Sinicyn, I A

To assess brain stem dysfunction in patients with hemodynamically significant stenosis of vertebral arteries (VA) using short latency brainstem auditory evoked potentials (BAEP). The study group included 50 patients (mean age 64±6 years) with hemodynamically significant extracranial VA stenosis. Patients with hemodynamically significant extracranial VA stenosis had BAEP abnormalities including the elongation of interpeak intervals I-V and peak V latency as well as the reduction of peak I amplitude. After transluminal balloon angioplasty with stenting of VA stenoses, there was a shortening of peak V latency compared to the preoperative period that reflected the improvement of brain stem conductive functions. Atherostenosis of vertebral arteries is characterized by the signs of brain stem dysfunction, predominantly in the pontomesencephal brain stem. After transluminal balloon angioplasty with stenting of VA, the improvement of brain stem conductive functions was observed.

Learning Disability Assessed through Audiologic and Physiologic Measures: A Case Study.

ERIC Educational Resources Information Center

Greenblatt, Edward R.; And Others

1983-01-01

The report describes a child with central auditory dysfunction, the first reported case where brain-stem dysfunction on audiologic tests were associated with specific electrophysiologic changes in the brain-stem auditory-evoked responses. (Author/CL)

Developmental dyslexia: predicting individual risk

PubMed Central

Thompson, Paul A; Hulme, Charles; Nash, Hannah M; Gooch, Debbie; Hayiou-Thomas, Emma; Snowling, Margaret J

2015-01-01

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

Strong motion deficits in dyslexia associated with DCDC2 gene alteration.

PubMed

Cicchini, Guido Marco; Marino, Cecilia; Mascheretti, Sara; Perani, Daniela; Morrone, Maria Concetta

2015-05-27

Dyslexia is a specific impairment in reading that affects 1 in 10 people. Previous studies have failed to isolate a single cause of the disorder, but several candidate genes have been reported. We measured motion perception in two groups of dyslexics, with and without a deletion within the DCDC2 gene, a risk gene for dyslexia. We found impairment for motion particularly strong at high spatial frequencies in the population carrying the deletion. The data suggest that deficits in motion processing occur in a specific genotype, rather than the entire dyslexia population, contributing to the large variability in impairment of motion thresholds in dyslexia reported in the literature. Copyright © 2015 the authors 0270-6474/15/358059-06$15.00/0.

Comorbidities in Preschool Children at Family Risk of Dyslexia

ERIC Educational Resources Information Center

Gooch, Debbie; Hulme, Charles; Nash, Hannah M.; Snowling, Margaret J.

2014-01-01

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…

Are There Lower Repetition Priming Effects in Children with Developmental Dyslexia? Priming Effects in Spanish with the Masked Lexical Decision Task.

PubMed

Nievas-Cazorla, Francisco; Soriano-Ferrer, Manuel; Sánchez-López, Pilar

2016-01-01

The aim of this study was to compare the reaction times and errors of Spanish children with developmental dyslexia to the reaction times and errors of readers without dyslexia on a masked lexical decision task with identity or repetition priming. A priming paradigm was used to study the role of the lexical deficit in dyslexic children, manipulating the frequency and length of the words, with a short Stimulus Onset Asynchrony (SOA = 150 ms) and degraded stimuli. The sample consisted of 80 participants from 9 to 14 years old, divided equally into a group with a developmental dyslexia diagnosis and a control group without dyslexia. Results show that identity priming is higher in control children (133 ms) than in dyslexic children (55 ms). Thus, the "frequency" and "word length" variables are not the source or origin of this reduction in identity priming reaction times in children with developmental dyslexia compared to control children.

Acquired dyslexia in a Turkish-English speaker.

PubMed

Raman, Ilhan; Weekes, Brendan S

2005-06-01

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 naïve view that reading and writing problems in Turkish are probably rare. We examined the extent to which phonological impairment and orthographic transparency influence reading disorders in a native Turkish speaker. BRB is a bilingual Turkish-English speaker with deep dysphasia accompanied by acquired dyslexia in both languages. The main findings are an effect of imageability on reading in Turkish coincident with surface dyslexia in English and preserved nonword reading. BRB's acquired dyslexia suggests that damage to phonological representations might have a consequence for learning to read in Turkish. We argue that BRB's acquired dyslexia has a common locus in chronic underactivation of phonological representations in Turkish and English. Despite a common locus, reading problems manifest themselves differently according to properties of the script and the type of task.

Mathematical abilities in dyslexic children: a diffusion tensor imaging study.

PubMed

Koerte, Inga K; Willems, Anna; Muehlmann, Marc; Moll, Kristina; Cornell, Sonia; Pixner, Silvia; Steffinger, Denise; Keeser, Daniel; Heinen, Florian; Kubicki, Marek; Shenton, Martha E; Ertl-Wagner, Birgit; Schulte-Körne, Gerd

2016-09-01

Dyslexia is characterized by a deficit in language processing which mainly affects word decoding and spelling skills. In addition, children with dyslexia also show problems in mathematics. However, for the latter, the underlying structural correlates have not been investigated. Sixteen children with dyslexia (mean age 9.8 years [0.39]) and 24 typically developing children (mean age 9.9 years [0.29]) group matched for age, gender, IQ, and handedness underwent 3 T MR diffusion tensor imaging as well as cognitive testing. Tract-Based Spatial Statistics were performed to correlate behavioral data with diffusion data. Children with dyslexia performed worse than controls in standardized verbal number tasks, such as arithmetic efficiency tests (addition, subtraction, multiplication, division). In contrast, the two groups did not differ in the nonverbal number line task. Arithmetic efficiency, representing the total score of the four arithmetic tasks, multiplication, and division, correlated with diffusion measures in widespread areas of the white matter, including bilateral superior and inferior longitudinal fasciculi in children with dyslexia compared to controls. Children with dyslexia demonstrated lower performance in verbal number tasks but performed similarly to controls in a nonverbal number task. Further, an association between verbal arithmetic efficiency and diffusion measures was demonstrated in widespread areas of the white matter suggesting compensatory mechanisms in children with dyslexia compared to controls. Taken together, poor fact retrieval in children with dyslexia is likely a consequence of deficits in the language system, which not only affects literacy skills but also impacts on arithmetic skills.

Atypical right hemisphere response to slow temporal modulations in children with developmental dyslexia.

PubMed

Cutini, Simone; Szűcs, Dénes; Mead, Natasha; Huss, Martina; Goswami, Usha

2016-12-01

Phase entrainment of neuronal oscillations is thought to play a central role in encoding speech. Children with developmental dyslexia show impaired phonological processing of speech, proposed theoretically to be related to atypical phase entrainment to slower temporal modulations in speech (<10Hz). While studies of children with dyslexia have found atypical phase entrainment in the delta band (~2Hz), some studies of adults with developmental dyslexia have shown impaired entrainment in the low gamma band (~35-50Hz). Meanwhile, studies of neurotypical adults suggest asymmetric temporal sensitivity in auditory cortex, with preferential processing of slower modulations by right auditory cortex, and faster modulations processed bilaterally. Here we compared neural entrainment to slow (2Hz) versus faster (40Hz) amplitude-modulated noise using fNIRS to study possible hemispheric asymmetry effects in children with developmental dyslexia. We predicted atypical right hemisphere responding to 2Hz modulations for the children with dyslexia in comparison to control children, but equivalent responding to 40Hz modulations in both hemispheres. Analyses of HbO concentration revealed a right-lateralised region focused on the supra-marginal gyrus that was more active in children with dyslexia than in control children for 2Hz stimulation. We discuss possible links to linguistic prosodic processing, and interpret the data with respect to a neural 'temporal sampling' framework for conceptualizing the phonological deficits that characterise children with developmental dyslexia across languages. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

Auditory Stimulus Processing and Task Learning Are Adequate in Dyslexia, but Benefits From Regularities Are Reduced.

PubMed

Daikhin, Luba; Raviv, Ofri; Ahissar, Merav

2017-02-01

The reading deficit for people with dyslexia is typically associated with linguistic, memory, and perceptual-discrimination difficulties, whose relation to reading impairment is disputed. We proposed that automatic detection and usage of serial sound regularities for individuals with dyslexia is impaired (anchoring deficit hypothesis), leading to the formation of less reliable sound predictions. Agus, Carrión-Castillo, Pressnitzer, and Ramus, (2014) reported seemingly contradictory evidence by showing similar performance by participants with and without dyslexia in a demanding auditory task that contained task-relevant regularities. To carefully assess the sensitivity of participants with dyslexia to regularities of this task, we replicated their study. Thirty participants with and 24 without dyslexia performed the replicated task. On each trial, a 1-s noise stimulus was presented. Participants had to decide whether the stimulus contained repetitions (was constructed from a 0.5-s noise segment repeated twice) or not. It is implicit in this structure that some of the stimuli with repetitions were themselves repeated across trials. We measured the ability to detect within-noise repetitions and the sensitivity to cross-trial repetitions of the same noise stimuli. We replicated the finding of similar mean performance. However, individuals with dyslexia were less sensitive to the cross-trial repetition of noise stimuli and tended to be more sensitive to repetitions in novel noise stimuli. These findings indicate that online auditory processing for individuals with dyslexia is adequate but their implicit retention and usage of sound regularities is indeed impaired.

Genomewide scan identifies susceptibility locus for dyslexia on Xq27 in an extended Dutch family.

PubMed

de Kovel, C G F; Hol, F A; Heister, J G A M; Willemen, J J H T; Sandkuijl, L A; Franke, B; Padberg, G W

2004-09-01

Dyslexia is a common disorder with a strong genetic component, but despite significant research effort, the aetiology is still largely unknown. To identify loci contributing to dyslexia risk. This was a genomewide linkage analysis in a single large family. Dutch families with at least two first degree relatives suffering from dyslexia participated in the study. Participants were recruited through an advertisement campaign in papers and magazines. The main outcome measure was linkage between genetic markers and dyslexia phenotype. Using parametric linkage analysis, we found strong evidence for a locus influencing dyslexia on Xq27.3 (multipoint lod = 3.68). Recombinations in two family members flanked an 8 cM region, comprising 11 currently confirmed genes. All four males carrying the risk haplotype had very low scores on the reading tests. The presentation in females was more variable, but 8/9 females carrying the risk haplotype were diagnosed dyslexic by our composite score, so we considered the putative risk allele to be dominant with reduced penetrance. Linkage was not found in an additional collection of affected sibling pairs. A locus influencing dyslexia risk is probably located between markers DXS1227 and DXS8091 on the X chromosome, closely situated to a locus indicated by a published genome scan of English sibling pairs. Although the locus may not be a common cause for dyslexia, the relatively small and gene poor region offers hope to identify the responsible gene.

Genomewide scan identifies susceptibility locus for dyslexia on Xq27 in an extended Dutch family

PubMed Central

de Kovel, C G F; Hol, F; Heister, J; Willemen, J; Sandkuijl, L; Franke, B; Padberg, G

2004-01-01

Context: Dyslexia is a common disorder with a strong genetic component, but despite significant research effort, the aetiology is still largely unknown. Objective: To identify loci contributing to dyslexia risk. Methods: This was a genomewide linkage analysis in a single large family. Dutch families with at least two first degree relatives suffering from dyslexia participated in the study. Participants were recruited through an advertisement campaign in papers and magazines. The main outcome measure was linkage between genetic markers and dyslexia phenotype. Results: Using parametric linkage analysis, we found strong evidence for a locus influencing dyslexia on Xq27.3 (multipoint lod = 3.68). Recombinations in two family members flanked an 8 cM region, comprising 11 currently confirmed genes. All four males carrying the risk haplotype had very low scores on the reading tests. The presentation in females was more variable, but 8/9 females carrying the risk haplotype were diagnosed dyslexic by our composite score, so we considered the putative risk allele to be dominant with reduced penetrance. Linkage was not found in an additional collection of affected sibling pairs. Conclusions: A locus influencing dyslexia risk is probably located between markers DXS1227 and DXS8091 on the X chromosome, closely situated to a locus indicated by a published genome scan of English sibling pairs. Although the locus may not be a common cause for dyslexia, the relatively small and gene poor region offers hope to identify the responsible gene. PMID:15342694

Neuroscience Literacy: "Brain Tells" as Signals of Brain Dysfunction Affecting Daily Life.

PubMed

Royeen, Charlotte B; Brašić, James R; Dvorak, Leah; Provoziak-O'Brien, Casey; Sethi, Chetna; Ahmad, S Omar

2016-01-01

The structures and circuits of the central and the peripheral nervous systems provide the basis for thinking, speaking, experiencing sensations, and performing perceptual and motor activities in daily life. Healthy people experience normal functioning without giving brain functions a second thought, while dysfunction of the neural circuits may lead to marked impairments in cognition, communication, sensory awareness, and performing perceptual and motor tasks. Neuroscience literacy provides the knowledge to associate the deficits observed in patients with the underlying deficits in the structures and circuits of the nervous system. The purpose of this paper is to begin the conversation in this area via a neuroscience literacy model of "Brain Tells," defined as stereotypical or observable behaviors often associated with brain dysfunction. Occupational therapists and other allied health professionals should be alert for the signs of "Brain Tells" that may be early warning signs of brain pathology. We also suggest that neuroscience literacy be emphasized in training provided to public safety workers, teachers, caregivers, and health care professionals at all levels.

Psychological Resources of Adults with Developmental Dyslexia

ERIC Educational Resources Information Center

Lockiewicz, Marta; Bogdanowicz, Katarzyna M.; Bogdanowicz, Marta

2014-01-01

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…

Visuospatial Superiority in Developmental Dyslexia: Myth or Reality?

ERIC Educational Resources Information Center

Brunswick, Nicola; Martin, G. Neil; Marzano, Lisa

2010-01-01

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"…

Reading and Dyslexia in Different Orthographies

ERIC Educational Resources Information Center

Brunswick, Nicola, Ed.; McDougall, Sine, Ed.; de Mornay Davies, Paul, Ed.

2010-01-01

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…

Language-Universal Sensory Deficits in Developmental Dyslexia: English, Spanish, and Chinese

ERIC Educational Resources Information Center

Goswami, Usha; Wang, H.-L. Sharon; Cruz, Alicia; Fosker, Tim; Mead, Natasha; Huss, Martina

2011-01-01

Studies in sensory neuroscience reveal the critical importance of accurate sensory perception for cognitive development. There is considerable debate concerning the possible sensory correlates of "phonological processing", the primary cognitive risk factor for developmental dyslexia. Across languages, children with dyslexia have a specific…

Personal Constructs and Attribution for Academic Success and Failure in Dyslexia.

ERIC Educational Resources Information Center

Humphrey, Neil; Mullins, Patricia M.

2002-01-01

A British study examined relationships between dyslexia and the ways in which students perceive themselves as learners, specifically their personal constructs and attributional styles. Results indicated that dyslexia has negative consequences for students' individual development. Suggestions are offered for making schools more "dyslexia…

Lateralized Temporal Order Judgement in Dyslexia

ERIC Educational Resources Information Center

Liddle, Elizabeth B.; Jackson, Georgina M.; Rorden, Chris; Jackson, Stephen R.

2009-01-01

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…

Dyslexia in Regular Orthographies: Manifestation and Causation

ERIC Educational Resources Information Center

Wimmer, Heinz; Schurz, Matthias

2010-01-01

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,…

Delayed Detection of Tonal Targets in Background Noise in Dyslexia

ERIC Educational Resources Information Center

Chait, Maria; Eden, Guinevere; Poeppel, David; Simon, Jonathan Z.; Hill, Deborah F.; Flowers, D. Lynn

2007-01-01

Individuals with developmental dyslexia are often impaired in their ability to process certain linguistic and even basic non-linguistic auditory signals. Recent investigations report conflicting findings regarding impaired low-level binaural detection mechanisms associated with dyslexia. Binaural impairment has been hypothesized to stem from a…

What Can Reduce Letter Migrations in Letter Position Dyslexia?

ERIC Educational Resources Information Center

Friedmann, Naama; Rahamim, Einav

2014-01-01

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…

A Critical Disability Pedagogy: Legitimizing Dyslexia

ERIC Educational Resources Information Center

Cosenza, Julie

2017-01-01

A common understanding is that dyslexia is the inability to spell words, the inability to recall symbols, the inability to recognize sight words, or the inability to decode. Dyslexia is often described in deficiency language--the inability to do something. Deficiency language is a product of special education and continues to dominate common…

Greek University Students with Dyslexia: An Interview Study

ERIC Educational Resources Information Center

Stampoltzis, Aglaia; Polychronopoulou, Stavroula

2009-01-01

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…

Mothers Speak Differently to Infants At-Risk for Dyslexia

ERIC Educational Resources Information Center

Kalashnikova, Marina; Goswami, Usha; Burnham, Denis

2018-01-01

Dyslexia is a neurodevelopmental disorder manifested in deficits in reading and spelling skills that is consistently associated with difficulties in phonological processing. Dyslexia is genetically transmitted, but its manifestation in a particular individual is thought to depend on the interaction of epigenetic and environmental factors. We adopt…

Cognitive Profiles of Chinese Adolescents with Dyslexia

ERIC Educational Resources Information Center

Chung, Kevin K. H.; Ho, Connie Suk-Han; Chan, David W.; Tsang, Suk-Man; Lee, Suk-Han

2010-01-01

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…

Auditory and Motor Rhythm Awareness in Adults with Dyslexia

ERIC Educational Resources Information Center

Thomson, Jennifer M.; Fryer, Ben; Maltby, James; Goswami, Usha

2006-01-01

Children with developmental dyslexia appear to be insensitive to basic auditory cues to speech rhythm and stress. For example, they experience difficulties in processing duration and amplitude envelope onset cues. Here we explored the sensitivity of adults with developmental dyslexia to the same cues. In addition, relations with expressive and…

Phonology, Reading Development, and Dyslexia: A Cross-Linguistic Perspective.

ERIC Educational Resources Information Center

Goswami, Usha

2002-01-01

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…

A Critical Analysis of Dyslexia Legislation in Three States

ERIC Educational Resources Information Center

Worthy, Jo; Villarreal, Doris; Godfrey, Vickie; DeJulio, Sam; Stefanski, Angela; Leitze, Amy; Cooper, Jennifer

2017-01-01

After a multitude of studies across more than a century, researchers have failed to consistently identify characteristics or patterns that distinguish dyslexia from other decoding challenges. Many researchers and educators argue the construct is too vague and contradictory to be useful for educators. Nevertheless, attention to dyslexia in policy…

Paired Associate Learning in Chinese Children with Dyslexia

ERIC Educational Resources Information Center

Li, Hong; Shu, Hua; McBride-Chang, Catherine; Liu, Hong Yun; Xue, Jin

2009-01-01

A total of 82 Chinese 11- and 12-year-olds with and without dyslexia were tested on four paired associate learning (PAL) tasks, phonological awareness, morphological awareness, rapid naming, and verbal short-term memory in three different experiments. Experiment 1 demonstrated that children with dyslexia were significantly poorer in visual-verbal…

Dyslexia and Severe Reading Disability.

ERIC Educational Resources Information Center

Ngandu, Kathleen M.

This handbook contains advice for the teacher in diagnosing dyslexia and developing an individualized program for overcoming severe reading problems. Observable characteristics of dyslexia are listed as an aid to the teacher's diagnosis, but it is emphasized that cooperation between the teacher and a reading specialist is of great importance in…

Dyslexia: A Mother's Role

ERIC Educational Resources Information Center

Washburn, Erin K.

2014-01-01

Children and adolescents with dyslexia are at greater risk for academic failure and socioemotional problems than their non-dyslexic peers. However, researchers have suggested that individuals with dyslexia can benefit from a strong support system. Further, researchers have noted that mothers are integral to their child's support system. However,…

(Dis)connections between Specific Language Impairment and Dyslexia in Chinese

ERIC Educational Resources Information Center

Wong, Anita M.-Y.; Ho, Connie S.-H.; Au, Terry K.-F.; Kidd, Joanna C.; Ng, Ashley K.-H.; Yip, Lesley P.-W.; Lam, Catherine C.-C.

2015-01-01

Specific language impairment (SLI) and dyslexia are found to co-occur in school-aged children learning Chinese, a non-alphabetic language (Wong, Kidd, Ho, & Au in "Sci Stud Read" 14:30--57, 2010). This paper examined the "Distinct" hypothesis--that SLI and dyslexia have different cognitive deficits and behavioural…

Meeting the Needs of Students with Dyslexia and Dyscalculia

ERIC Educational Resources Information Center

Witzel, Bradley; Mize, Minnie

2018-01-01

Understanding dyslexia and dyscalculia is not only important to helping students achieve, it has also been recently legislated in one southeastern state. The purpose of the North Carolina House Bill 149 is to ensure that students identified with learning disabilities, including dyslexia and dyscalculia, receive the appropriate assessment and…

Impaired Balance in Developmental Dyslexia? A Meta-Analysis of the Contending Evidence

ERIC Educational Resources Information Center

Rochelle, Kim S. H.; Talcott, Joel B.

2006-01-01

Background: Developmental dyslexia is typically defined by deficits in phonological skills, but it is also associated with anomalous performance on measures of balance. Although balance assessments are included in several screening batteries for dyslexia, the association between impairments in literacy and deficits in postural stability could be…

Electrophysiological Indices of Phonological Impairments in Dyslexia

ERIC Educational Resources Information Center

Desroches, Amy S.; Newman, Randy Lynn; Robertson, Erin K.; Joanisse, Marc F.

2013-01-01

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…

Academic Motivation in Children with Dyslexia

ERIC Educational Resources Information Center

Lodygowska, Ewa; Chec, Magdalena; Samochowiec, Agnieszka

2017-01-01

The authors' purpose was to determine which form of therapeutic aid may influence academic approach and avoidance motivation in children with dyslexia. There were 165 children with dyslexia assessed with the use of "I and my school" questionnaire. The authors considered the children's previous therapeutic experience and on its basis they…

Assessment of Dyslexia

ERIC Educational Resources Information Center

Proctor, Carla M.; Mather, Nancy; Stephens-Pisecco, Tammy L.; Jaffe, Lynne E.

2017-01-01

School psychologists are often involved in evaluating students who have been referred for reading problems or are suspected of having dyslexia. To accomplish this task, it is important to have a thorough understanding of dyslexia, and know what factors to consider. Therefore, the purposes of this article are to describe: (1) the primary and…

The Diagnosis Dilemma: Dyslexia and Visual-Spatial Ability

ERIC Educational Resources Information Center

Kotsopoulos, Donna; Zambrzycka, Joanna; Makosz, Samantha; Asdrubolini, Emma; Babic, Jovana; Best, Olivia; Bines, Tara; Cook, Samantha; Farrell, Natalie; Gisondi, Victoria; Scott, Meghan; Siderius, Christina; Smith, Dyoni

2017-01-01

Visual-spatial ability is important for mathematics learning but also for future STEM participation. Some studies report children with dyslexia have superior visual-spatial skills and other studies report a deficit. We sought to further explore the relationship between children formally identified as having dyslexia and visual-spatial ability.…

Visual Stress in Adults with and without Dyslexia

ERIC Educational Resources Information Center

Singleton, Chris; Trotter, Susannah

2005-01-01

The relationship between dyslexia and visual stress (sometimes known as Meares-Irlen syndrome) is uncertain. While some theorists have hypothesised an aetiological link between the two conditions, mediated by the magnocellular visual system, at the present time the predominant theories of dyslexia and visual stress see them as distinct, unrelated…

Phonological Precedence in Dyslexia: A Case Study

ERIC Educational Resources Information Center

Schneider-Zioga, Patricia

2012-01-01

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…

High Reading Skills Mask Dyslexia in Gifted Children

ERIC Educational Resources Information Center

van Viersen, Sietske; Kroesbergen, Evelyn H.; Slot, Esther M.; de Bree, Elise H.

2016-01-01

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…

Surface developmental dyslexia is as prevalent as phonological dyslexia when appropriate control groups are employed.

PubMed

Wybrow, Dean P; Hanley, J Richard

2015-01-01

Previous investigations of the incidence of developmental surface and phonological dyslexia using reading-age-matched control groups have identified many more phonological dyslexics (poor nonword reading relative to irregular-word reading) than surface dyslexics (poor irregular-word reading relative to nonword reading). However, because the measures that have been used to estimate reading age include irregular-word reading ability, they appear inappropriate for assessing the incidence of surface dyslexia. The current study used a novel method for generating control groups whose reading ability was matched to that of the dyslexic sample. The incidence of surface dyslexia was assessed by comparing dyslexic performance with that of a control group who were matched with the dyslexics on a test of nonword reading. The incidence of phonological dyslexia was assessed with reference to a control group who were matched with the dyslexics at irregular-word reading. These control groups led to the identification of an approximately equal number of children with surface and phonological dyslexia. It appeared that selecting control participants who were matched with dyslexics for reading age led to the recruitment of individuals with relatively high nonword reading scores relative to their irregular-word reading scores compared with other types of control group. The theoretical implications of these findings are discussed.

Improvement of the Error-detection Mechanism in Adults with Dyslexia Following Reading Acceleration Training.

PubMed

Horowitz-Kraus, Tzipi

2016-05-01

The error-detection mechanism aids in preventing error repetition during a given task. Electroencephalography demonstrates that error detection involves two event-related potential components: error-related and correct-response negativities (ERN and CRN, respectively). Dyslexia is characterized by slow, inaccurate reading. In particular, individuals with dyslexia have a less active error-detection mechanism during reading than typical readers. In the current study, we examined whether a reading training programme could improve the ability to recognize words automatically (lexical representations) in adults with dyslexia, thereby resulting in more efficient error detection during reading. Behavioural and electrophysiological measures were obtained using a lexical decision task before and after participants trained with the reading acceleration programme. ERN amplitudes were smaller in individuals with dyslexia than in typical readers before training but increased following training, as did behavioural reading scores. Differences between the pre-training and post-training ERN and CRN components were larger in individuals with dyslexia than in typical readers. Also, the error-detection mechanism as represented by the ERN/CRN complex might serve as a biomarker for dyslexia and be used to evaluate the effectiveness of reading intervention programmes. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Evaluation of the Bangor Dyslexia Test (BDT) for use with Adults.

PubMed

Reynolds, Andrea Elaine; Caravolas, Markéta

2016-02-01

The Bangor Dyslexia Test (BDT) is a short, easy-to-administer screener for use with a broad age range, which has been in use in the UK for over three decades. A distinctive feature of the battery is its focus on skills requiring aspects of verbal and phonological processing without, however, measuring literacy skills per se. Despite its longstanding existence and usage, there has been no evaluation of the psychometric properties of the battery as an adult dyslexia screener. We examined the psychometric properties of the BDT and evaluated its capacity to discriminate between adults with and without dyslexia. A large archival sample of university students with dyslexia (n = 193) and students with no reported literacy difficulties (n = 40) were compared on the BDT as well as on literacy and cognitive measures. Statistical analyses revealed the BDT to be a reliable (α = .72) and valid dyslexia screening tool with the capacity to effectively identify adults at risk of the disorder with an overall classification rate of 94% (sensitivity 96.4% and specificity 82.5%). In addition, higher indices of dyslexia risk on the BDT were associated with lower scores on standardized measures of literacy. Copyright © 2016 John Wiley & Sons, Ltd.

IQ of four-year-olds who go on to develop dyslexia.

PubMed

van Bergen, Elsje; de Jong, Peter F; Maassen, Ben; Krikhaar, Evelien; Plakas, Anna; van der Leij, Aryan

2014-01-01

Do children who go on to develop dyslexia show normal verbal and nonverbal development before reading onset? According to the aptitude-achievement discrepancy model, dyslexia is defined as a discrepancy between intelligence and reading achievement. One of the underlying assumptions is that the general cognitive development of children who fail to learn to read has been normal. The current study tests this assumption. In addition, we investigated whether possible IQ deficits are uniquely related to later reading or are also related to arithmetic. Four-year-olds (N = 212) with and without familial risk for dyslexia were assessed on 10 IQ subtests. Reading and arithmetic skills were measured 4 years later, at the end of Grade 2. Relative to the controls, the at-risk group without dyslexia had subtle impairments only in the verbal domain, whereas the at-risk group with dyslexia lagged behind across IQ tasks. Nonverbal IQ was associated with both reading and arithmetic, whereas verbal IQ was uniquely related to later reading. The children who went on to develop dyslexia performed relatively poorly in both verbal and nonverbal abilities at age 4, which challenges the discrepancy model. Furthermore, we discuss possible causal and epiphenomenal models explaining the links between early IQ and later reading. © Hammill Institute on Disabilities 2013.

Alcohol-induced one-carbon metabolism impairment promotes dysfunction of DNA base excision repair in adult brain.

PubMed

Fowler, Anna-Kate; Hewetson, Aveline; Agrawal, Rajiv G; Dagda, Marisela; Dagda, Raul; Moaddel, Ruin; Balbo, Silvia; Sanghvi, Mitesh; Chen, Yukun; Hogue, Ryan J; Bergeson, Susan E; Henderson, George I; Kruman, Inna I

2012-12-21

The brain is one of the major targets of chronic alcohol abuse. Yet the fundamental mechanisms underlying alcohol-mediated brain damage remain unclear. The products of alcohol metabolism cause DNA damage, which in conditions of DNA repair dysfunction leads to genomic instability and neural death. We propose that one-carbon metabolism (OCM) impairment associated with long term chronic ethanol intake is a key factor in ethanol-induced neurotoxicity, because OCM provides cells with DNA precursors for DNA repair and methyl groups for DNA methylation, both critical for genomic stability. Using histological (immunohistochemistry and stereological counting) and biochemical assays, we show that 3-week chronic exposure of adult mice to 5% ethanol (Lieber-Decarli diet) results in increased DNA damage, reduced DNA repair, and neuronal death in the brain. These were concomitant with compromised OCM, as evidenced by elevated homocysteine, a marker of OCM dysfunction. We conclude that OCM dysfunction plays a causal role in alcohol-induced genomic instability in the brain because OCM status determines the alcohol effect on DNA damage/repair and genomic stability. Short ethanol exposure, which did not disturb OCM, also did not affect the response to DNA damage, whereas additional OCM disturbance induced by deficiency in a key OCM enzyme, methylenetetrahydrofolate reductase (MTHFR) in Mthfr(+/-) mice, exaggerated the ethanol effect on DNA repair. Thus, the impact of long term ethanol exposure on DNA repair and genomic stability in the brain results from OCM dysfunction, and MTHFR mutations such as Mthfr 677C→T, common in human population, may exaggerate the adverse effects of ethanol on the brain.

[Clinical and neurophysiological data of neurofeedback therapy in children with ADHD].

PubMed

Kubik, Alicja; Kubik, Paweł; Stanios, Martyna; Kraj, Bogusława

2016-01-01

ADHD occurs in 3% of school-age children (and in 70% of them in adulthood) and represents an important medical and social problem. It is characterized by attention deficits, hyperactivity and impulsiveness. Neurofeedback therapy (EEG biofeedback, NF) is carried out based on the analysis of EEG. To investigate the effect of NF therapy on clinical status and parameters of the EEG in ADHD. In the years 2007-2014, 287 children (191 boys), aged 6-17 years were included into the study. Some children with ADHD had other coexisting disorders like: tics, dyslexia, emotional or behavior disorders. Visual analysis of EEG was made and 7 selected parameters of bioelectrical activity were assessed. EEG tracing before and after NF therapy were compared. NF therapy lasted from 9 months to 3 years (mean 1.5 years). 60-240 NF training sessions were performed with the use of NF device, video-games and 16-channel Elmiko devices. Statistical analysis of the results was made. Children with ADHD additionally presented low self-esteem, anxiety and sleep disorders. The baseline theta/beta ratio in children with ADHD and ADHD with cooccurring dyslexia was >4.0 and in children with ADHD and coexisting tics 3.0-3.8, with coexisting behavioral disorders 3.7-4.0 and emotional disorders 3.3-3.7. After therapy, this ratio decreased significantly in all groups, but most significantly in ADHD and ADHD with dyslexia group. In the group with dyslexia theta and alpha activity in the left fronto-temporo-parietal region (the speech centers) has been increased. In children with ADHD and behavior disorders right-sided paroxysmal changes in the form of slow and sharp waves in the temporo-centro-parietal regions were found. In emotionally disturbed children increased fast beta activity in the right hemisphere (anxiety, fear) was observed. Initially NF therapy reduced hyperactivity and impulsivity of children, subsequently improvement of attention was observed and eventually reduction of emotional and behavior disturbances was noticed. Noticeable improvement in the self-esteem was observed as well. The therapy had a positive impact on the spatial organization of EEG in each group. It proved to be particularly useful in children with ADHD and dyslexia. Neurofeedback therapy is a valuable tool with beneficial impact on children with ADHD and accompanying disorders. Characteristics of brain bioelectric activity provides a reliable basis to establish individual EEG bio-feedback protocols of therapy in children and monitor the effectiveness of treatment. In the last 4 years the number of children with ADHD and cooccurring tics who applied for neurofeedback therapy has increased significantly.

New Diagnostic Terminology for Minimal Brain Dysfunction.

ERIC Educational Resources Information Center

Shaywitz, Bennett A.; And Others

1979-01-01

Minimal brain dysfunction has been redefined by the American Psychological Association as attention deficit disorder (ADD) and subdivided into categories with and without hyperactivity. The revised 'Diagnostic and Statistical Manual' (DSM III) is now undergoing field trials. Journal Availability: C. V. Mosby Company, 11830 Westline Industrial…

Brain Basics: Know Your Brain

MedlinePlus

... free mailed brochure Table of Contents Introduction The Architecture of the Brain The Geography of Thought The ... brain is diseased or dysfunctional. Image 1 The Architecture of the Brain The brain is like a ...

Developmental Dyslexia: Early Precursors, Neurobehavioral Markers, and Biological Substrates

ERIC Educational Resources Information Center

Benasich, April A., Ed.; Fitch, R. Holly, Ed.

2012-01-01

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…

Spoken Sentence Production in College Students with Dyslexia: Working Memory and Vocabulary Effects

ERIC Educational Resources Information Center

Wiseheart, Rebecca; Altmann, Lori J. P.

2018-01-01

Background: Individuals with dyslexia demonstrate syntactic difficulties on tasks of language comprehension, yet little is known about spoken language production in this population. Aims: To investigate whether spoken sentence production in college students with dyslexia is less proficient than in typical readers, and to determine whether group…

A Comparative Case Study of Learning Strategies and Recommendations of Five Professional Musicians with Dyslexia

ERIC Educational Resources Information Center

Nelson, Kent Peter; Hourigan, Ryan M.

2016-01-01

Many of the characteristics of dyslexia--such as difficulties with decoding written symbols, phonemic awareness, physical coordination, and readable handwriting--may adversely affect music learning. Despite challenges, individuals with dyslexia can succeed in music. The purpose of this study was to examine the perceptions of five professional…

Non-Adjacent Dependency Learning in Infants at Familial Risk of Dyslexia

ERIC Educational Resources Information Center

Kerkhoff, Annemarie; de Bree, Elise; de Klerk, Maartje; Wijnen, Frank

2013-01-01

This study tests the hypothesis that developmental dyslexia is (partly) caused by a deficit in implicit sequential learning, by investigating whether infants at familial risk of dyslexia can track non-adjacent dependencies in an artificial language. An implicit learning deficit would hinder detection of such dependencies, which mark grammatical…

Developmental Dyslexia: An Evaluation of a Theory.

ERIC Educational Resources Information Center

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…

Dyslexia Profiles across Orthographies Differing in Transparency: An Evaluation of Theoretical Predictions Contrasting English and Greek

ERIC Educational Resources Information Center

Diamanti, Vassiliki; Goulandris, Nata; Campbell, Ruth; Protopapas, Athanassios

2018-01-01

We examined the manifestation of dyslexia in a cross-linguistic study contrasting English and Greek children with dyslexia compared to chronological age and reading-level control groups on reading accuracy and fluency, phonological awareness, short-term memory, rapid naming, orthographic choice, and spelling. Materials were carefully matched…

Using Photography and Art in Concept Mapping Research with Adults with Dyslexia

ERIC Educational Resources Information Center

Williams Carawan, Lena; Nalavany, Blace

2010-01-01

Reflexive photography for individual interviews and the use of art with focus groups provides a valuable method for exploring the psychosocial issues encountered by adults with dyslexia. Reflexive photography and art is particularly appropriate when interviewing adults with dyslexia who may have difficulty expressing and focusing on what they want…

Dyslexia and Inclusion: Assessment and Support in Higher Education.

ERIC Educational Resources Information Center

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…

Double Dissociation of Functions in Developmental Dyslexia and Dyscalculia

ERIC Educational Resources Information Center

Rubinsten, Orly; Henik, Avishai

2006-01-01

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…

Speech Perception Abilities of Adults with Dyslexia: Is There Any Evidence for a True Deficit?

ERIC Educational Resources Information Center

Hazan, Valerie; Messaoud-Galusi, Souhila; Rosen, Stuart; Nouwens, Suzan; Shakespeare, Bethanie

2009-01-01

Purpose: This study investigated whether adults with dyslexia show evidence of a consistent speech perception deficit by testing phoneme categorization and word perception in noise. Method: Seventeen adults with dyslexia and 20 average readers underwent a test battery including standardized reading, language and phonological awareness tests, and…

An Attempt to Simulate Letter-by-Letter Dyslexia in Normal Readers

ERIC Educational Resources Information Center

Fiset, Stephanie; Arguin, Martin; Fiset, Daniel

2006-01-01

We attempted to simulate the main features of letter-by-letter (LBL) dyslexia in normal readers through stimulus degradation (i.e. contrast reduction and removal of high spatial frequencies). The results showed the word length and the letter confusability effects characteristic of LBL dyslexia. However, the interaction of letter confusability and…

Dyslexia at a Behavioural and a Cognitive Level

ERIC Educational Resources Information Center

Helland, Turid

2007-01-01

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…

Identifying Students with Dyslexia in Higher Education

ERIC Educational Resources Information Center

Tops, Wim; Callens, Maaike; Lammertyn, Jan; Van Hees, Valerie; Brysbaert, Marc

2012-01-01

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…

Rise Time Perception and Detection of Syllable Stress in Adults with Developmental Dyslexia

ERIC Educational Resources Information Center

Leong, Victoria; Hamalainen, Jarmo; Soltesz, Fruzsina; Goswami, Usha

2011-01-01

Introduction: The perception of syllable stress has not been widely studied in developmental dyslexia, despite strong evidence for auditory rhythmic perceptual difficulties. Here we investigate the hypothesis that perception of sound rise time is related to the perception of syllable stress in adults with developmental dyslexia. Methods: A…

Impaired Perception of Syllable Stress in Children with Dyslexia: A Longitudinal Study

ERIC Educational Resources Information Center

Goswami, Usha; Mead, Natasha; Fosker, Tim; Huss, Martina; Barnes, Lisa; Leong, Victoria

2013-01-01

Prosodic patterning is a key structural element of spoken language. However, the potential role of prosodic awareness in the phonological difficulties that characterise children with developmental dyslexia has been little studied. Here we report the first longitudinal study of sensitivity to syllable stress in children with dyslexia, enabling the…

Word Learning Deficits in Children with Dyslexia

ERIC Educational Resources Information Center

Alt, Mary; Hogan, Tiffany; Green, Samuel; Gray, Shelley; Cabbage, Kathryn; Cowan, Nelson

2017-01-01

Purpose: The purpose of this study is to investigate word learning in children with dyslexia to ascertain their strengths and weaknesses during the configuration stage of word learning. Method: Children with typical development (N = 116) and dyslexia (N = 68) participated in computer-based word learning games that assessed word learning in 4 sets…

Impaired Visual Attention in Children with Dyslexia.

ERIC Educational Resources Information Center

Heiervang, Einar; Hugdahl, Kenneth

2003-01-01

A cue-target visual attention task was administered to 25 children (ages 10-12) with dyslexia. Results showed a general pattern of slower responses in the children with dyslexia compared to controls. Subjects also had longer reaction times in the short and long cue-target interval conditions (covert and overt shift of attention). (Contains…

Developmental Dyslexia and Widespread Activation across the Cerebellar Hemispheres

ERIC Educational Resources Information Center

Baillieux, Hanne; Vandervliet, Everhard J. M.; Manto, Mario; Parizel, Paul M.; De Deyn, Peter P.; Marien, Peter

2009-01-01

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…

Dyslexia and the Studio: Bridging the Gap between Theory and Practice

ERIC Educational Resources Information Center

Alden, Sandy; Pollock, Venda Louise

2011-01-01

It is generally accepted that art and design related disciplines attract a higher proportion of students with dyslexia than traditional academic counterparts. Combined with this is a prevalent perception that dyslexia predominantly affects students' writing and linguistic ability and it is this, as well as an increased visual-spatial sensibility,…

Kindergarten through Second-Grade Teachers' Knowledge and Beliefs about Dyslexia Assessment and Retention

ERIC Educational Resources Information Center

Foreman-Sinclair, Kimberly Ann

2012-01-01

The purpose of this mixed research study was to investigate early assessment and identification for dyslexia in kindergarten through second grade, and to examine whether teachers' knowledge and beliefs lead to the practice of retaining students in grade rather than recommending formal dyslexia assessment. This study investigated both kindergarten…

Whole-Word Shape Effect in Dyslexia

ERIC Educational Resources Information Center

Lavidor, Michal

2011-01-01

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…

Genetics and Neuroscience in Dyslexia: Perspectives for Education and Remediation

ERIC Educational Resources Information Center

Schulte-Korne, Gerd; Ludwig, Kerstin U.; el Sharkawy, Jennifer; Nothen, Markus M.; Muller-Myhsok, Bertram; Hoffmann, Per

2007-01-01

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…

Longitudinal Stability of Pre-Reading Skill Profiles of Kindergarten Children: Implications for Early Screening and Theories of Reading

ERIC Educational Resources Information Center

Ozernov-Palchik, Ola; Norton, Elizabeth S.; Sideridis, Georgios; Beach, Sara D.; Wolf, Maryanne; Gabrieli, John D. E.; Gaab, Nadine

2017-01-01

Research suggests that early identification of developmental dyslexia is important for mitigating the negative effects of dyslexia, including reduced educational attainment and increased socioemotional difficulties. The strongest pre-literacy predictors of dyslexia are rapid automatized naming (RAN), phonological awareness (PA), letter knowledge,…

Successful Strategies of Individuals with Dyslexia in the Field of Music: A Comparative Case Study

ERIC Educational Resources Information Center

Nelson, Kent Peter

2014-01-01

Many of the symptoms of dyslexia--such as difficulties with decoding written symbols, phonemic awareness, physical coordination, and readable handwriting--may adversely affect music learning. Despite challenges, some individuals with dyslexia succeed in music. The purpose of this study was to examine the perceptions of five professional musicians…

A Quasi-Experimental Analysis of Second Graders with Dyslexia Using the Motor Markers in the Cerebellar Deficit Hypothesis

ERIC Educational Resources Information Center

Stark, Sandra Kathleen

2013-01-01

Developmental dyslexia is a specific impairment of reading ability in the presence of normal intelligence and adequate reading instruction. Current research has linked dyslexia to genetic underpinnings, which are identifiable. Furthermore, there are cognitive processes that are influenced by unique genetically programmed neural networks that…

A Critical Approach towards Dyslexia

ERIC Educational Resources Information Center

Leonard, Bobby

2005-01-01

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…

Dyslexia Training Program. What Works Clearinghouse Intervention Report

ERIC Educational Resources Information Center

What Works Clearinghouse, 2010

2010-01-01

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…

Auditory Temporal Processing and Working Memory: Two Independent Deficits for Dyslexia

ERIC Educational Resources Information Center

Fostick, Leah; Bar-El, Sharona; Ram-Tsur, Ronit

2012-01-01

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…

Lecturer Perspectives on Dyslexia within One Greek University: A Pilot Study

ERIC Educational Resources Information Center

Stampoltzis, Aglaia; Tsitsou, Elisavet; Plesti, Helen; Kalouri, Rani

2015-01-01

Introduction: Dyslexia is a learning difficulty which affects people in different ways. During the last decades the number of students with dyslexia entering higher education increased steadily. Method: This paper reports a pilot study exploring the attitudes, views and experiences of faculty members at one small size Greek university regarding…

The Learning Experiences of Students with Dyslexia in a Greek Higher Education Institution

ERIC Educational Resources Information Center

Stampoltzis , Aglaia; Tsitsou, Elisavet; Plesti, Helen; Kalouri, Rani

2015-01-01

Dyslexia is the most common declared disability at universities which primarily affects reading, writing, speed of processing and organization. Many students with dyslexia have "invisible" difficulties that require different types of accommodations. The aim of this study is to give voice to the learning experiences of ten students with…

Foreign Language Reading and Spelling in Gifted Students with Dyslexia in Secondary Education

ERIC Educational Resources Information Center

van Viersen, Sietske; de Bree, Elise H.; Kalee, Lilian; Kroesbergen, Evelyn H.; de Jong, Peter F.

2017-01-01

A few studies suggest that gifted children with dyslexia have better literacy skills than averagely intelligent children with dyslexia. This finding aligns with the hypothesis that giftedness-related factors provide compensation for poor reading. The present study investigated whether, as in the native language (NL), the level of foreign language…

Motor Skills, Automaticity and Developmental Dyslexia: A Review of the Research Literature

ERIC Educational Resources Information Center

Savage, Robert

2004-01-01

This paper reviews a body of prominent theories of automaticity in developmental dyslexia. The first part of the review considers the relationship between dyslexia and rapid automatic naming and fluency. Additional theoretical and empirical advances are suggested to this already strong research base. In particular, there is a need is for…

Anchoring the Deficit of the Anchor Deficit: Dyslexia or Attention?

ERIC Educational Resources Information Center

Willburger, Edith; Landerl, Karin

2010-01-01

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…

Reduced Sensitivity to Slow-Rate Dynamic Auditory Information in Children with Dyslexia

ERIC Educational Resources Information Center

Poelmans, Hanne; Luts, Heleen; Vandermosten, Maaike; Boets, Bart; Ghesquiere, Pol; Wouters, Jan

2011-01-01

The etiology of developmental dyslexia remains widely debated. An appealing theory postulates that the reading and spelling problems in individuals with dyslexia originate from reduced sensitivity to slow-rate dynamic auditory cues. This low-level auditory deficit is thought to provoke a cascade of effects, including inaccurate speech perception…

IQ of Four-Year-Olds Who Go on to Develop Dyslexia

ERIC Educational Resources Information Center

van Bergen, Elsje; de Jong, Peter F.; Maassen, Ben; Krikhaar, Evelien; Plakas, Anna; van der Leij, Aryan

2014-01-01

Do children who go on to develop dyslexia show normal verbal and nonverbal development before reading onset? According to the aptitude-achievement discrepancy model, dyslexia is defined as a discrepancy between intelligence and reading achievement. One of the underlying assumptions is that the general cognitive development of children who fail to…

Auditory Stimulus Processing and Task Learning Are Adequate in Dyslexia, but Benefits from Regularities Are Reduced

ERIC Educational Resources Information Center

Daikhin, Luba; Raviv, Ofri; Ahissar, Merav

2017-01-01

Purpose: The reading deficit for people with dyslexia is typically associated with linguistic, memory, and perceptual-discrimination difficulties, whose relation to reading impairment is disputed. We proposed that automatic detection and usage of serial sound regularities for individuals with dyslexia is impaired (anchoring deficit hypothesis),…

Syntactic Comprehension in Reading and Listening: A Study with French Children with Dyslexia

ERIC Educational Resources Information Center

Casalis, Severine; Leuwers, Christel; Hilton, Heather

2013-01-01

This study examined syntactic comprehension in French children with dyslexia in both listening and reading. In the first syntactic comprehension task, a partial version of the Epreuve de Comprehension syntaxico-semantique (ECOSSE test; French adaptation of Bishop's test for receptive grammar test) children with dyslexia performed at a lower level…

Chinese Handwriting Performance of Primary School Children with Dyslexia

ERIC Educational Resources Information Center

Lam, Sutie S. T.; Au, Ricky K. C.; Leung, Howard W. H.; Li-Tsang, Cecilia W. P.

2011-01-01

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…

"Dyslexia": Toward Semantical Clarification.

ERIC Educational Resources Information Center

Manzo, Anthony V.; Duffelmeyer, Fred

A formulated definition of the term dyslexia is proposed in this paper in order to clarify the semantical confusion which exists among both specialists and the general public. Dyslexia is explained as a generic term for severe and puzzling reading disability, found to be both acute (where reading-age lags 25 percent or more below mental age) and…

Developmental Dyslexia in Chinese and English Populations: Dissociating the Effect of Dyslexia from Language Differences

ERIC Educational Resources Information Center

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.

2010-01-01

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…

Teacher knowledge of basic language concepts and dyslexia.

PubMed

Washburn, Erin K; Joshi, R Malatesha; Binks-Cantrell, Emily S

2011-05-01

Roughly one-fifth of the US population displays one or more symptoms of dyslexia: a specific learning disability that affects an individual's ability to process written language. Consequently, elementary school teachers are teaching students who struggle with inaccurate or slow reading, poor spelling, poor writing, and other language processing difficulties. Findings from studies have indicated that teachers lack essential knowledge needed to teach struggling readers, particularly children with dyslexia. However, few studies have sought to assess teachers' knowledge and perceptions about dyslexia in conjunction with knowledge of basic language concepts related to reading instruction. Thus, the purpose of the present study was to examine elementary school teachers' knowledge of basic language concepts and their knowledge and perceptions about dyslexia. Findings from the present study indicated that teachers, on average, were able to display implicit skills related to certain basic language concepts (i.e. syllable counting), but failed to demonstrate explicit knowledge of others (i.e. phonics principles). Also, teachers seemed to hold the common misconception that dyslexia is a visual processing deficit rather than phonological processing deficit. Copyright © 2011 John Wiley & Sons, Ltd.

Beyond Auditory Sensory Processing Deficits: Lexical Tone Perception Deficits in Chinese Children With Developmental Dyslexia.

PubMed

Tong, Xiuhong; Tong, Xiuli; King Yiu, Fung

Increasing evidence suggests that children with developmental dyslexia exhibit a deficit not only at the segmental level of phonological processing but also, by extension, at the suprasegmental level. However, it remains unclear whether such a suprasegmental phonological processing deficit is due to a difficulty in processing acoustic cues of speech rhythm, such as rise time and intensity. This study set out to investigate to what extent suprasegmental phonological processing (i.e., Cantonese lexical tone perception) and rise time sensitivity could distinguish Chinese children with dyslexia from typically developing children. Sixteen children with dyslexia and 44 age-matched controls were administered a Cantonese lexical tone perception task, psychoacoustic tasks, a nonverbal reasoning ability task, and word reading and dictation tasks. Children with dyslexia performed worse than controls on Cantonese lexical tone perception, rise time, and intensity. Furthermore, Cantonese lexical tone perception appeared to be a stable indicator that distinguishes children with dyslexia from controls, even after controlling for basic auditory processing skills. These findings suggest that suprasegmental phonological processing (i.e., lexical tone perception) is a potential factor that accounts for reading difficulty in Chinese.

Reading disorders and dyslexia.

PubMed

Hulme, Charles; Snowling, Margaret J

2016-12-01

We review current knowledge about the nature of reading development and disorders, distinguishing between the processes involved in learning to decode print, and the processes involved in reading comprehension. Children with decoding difficulties/dyslexia experience deficits in phoneme awareness, letter-sound knowledge and rapid automatized naming in the preschool years and beyond. These phonological/language difficulties appear to be proximal causes of the problems in learning to decode print in dyslexia. We review data from a prospective study of children at high risk of dyslexia to show that being at family risk of dyslexia is a primary risk factor for poor reading and children with persistent language difficulties at school entry are more likely to develop reading problems. Early oral language difficulties are strong predictors of later difficulties in reading comprehension. There are two distinct forms of reading disorder in children: dyslexia (a difficulty in learning to translate print into speech) and reading comprehension impairment. Both forms of reading problem appear to be predominantly caused by deficits in underlying oral language skills. Implications for screening and for the delivery of robust interventions for language and reading are discussed.

Development of reading and phonological skills of children at family risk for dyslexia: a longitudinal analysis from kindergarten to sixth grade.

PubMed

Dandache, Sophie; Wouters, Jan; Ghesquière, Pol

2014-11-01

The main focus of this article is to develop a better understanding of the developmental trajectories of literacy and phonological skills within Dutch-speaking children. Children at high and low risk for dyslexia were followed and compared at four different moments: kindergarten and first, third and sixth grades. Three groups were then compared: (1) dyslexic readers; (2) normal readers at high risk for dyslexia; and (3) normal readers at low risk for dyslexia. Children diagnosed with dyslexia scored lower than high-risk normal readers on phonological awareness (PA), rapid automatized naming (RAN), verbal short-term memory and literacy skills. Normal readers at high risk scored between both groups, confirming that dyslexia is to be considered as a continuum rather than an all-or-none condition. Growth analyses showed that the three groups evolved similarly on all measures except for phoneme deletion and literacy measures. Finally, solely PA and RAN explained a significant amount of variance in the evolution of reading skills. Copyright © 2014 John Wiley & Sons, Ltd.

Exploring Text and Icon Graph Interpretation in Students with Dyslexia: An Eye-tracking Study.

PubMed

Kim, Sunjung; Wiseheart, Rebecca

2017-02-01

A growing body of research suggests that individuals with dyslexia struggle to use graphs efficiently. Given the persistence of orthographic processing deficits in dyslexia, this study tested whether graph interpretation deficits in dyslexia are directly related to difficulties processing the orthographic components of graphs (i.e. axes and legend labels). Participants were 80 college students with and without dyslexia. Response times and eye movements were recorded as students answered comprehension questions about simple data displayed in bar graphs. Axes and legends were labelled either with words (mixed-modality graphs) or icons (orthography-free graphs). Students also answered informationally equivalent questions presented in sentences (orthography-only condition). Response times were slower in the dyslexic group only for processing sentences. However, eye tracking data revealed group differences for processing mixed-modality graphs, whereas no group differences were found for the orthography-free graphs. When processing bar graphs, students with dyslexia differ from their able reading peers only when graphs contain orthographic features. Implications for processing informational text are discussed. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

The overstimulated state of dyslexia: perception, knowledge, and learning.

PubMed

Arkowitz, S W

2000-01-01

Dyslexia is far more than a learning disorder; it has significant impact on personality organization. While dyslexia usually begins to manifest most clearly in early latency when the challenge of learning to read is at its height, often the dyslexic child's ego development and functioning has already been adversely affected. The literature from neuropsychology suggests that dyslexia is a subtle language-processing disorder that affects emotional, cognitive, and social development. The neuroanatomical literature also suggests a significant correlation between the neurodevelopmental basis for dyslexia, the caregiving environment, and psychological development. These two bodies of literature and analytic observations of a dyslexic patient suggest that the dyslexic individual may have a neurological deficit that increases vulnerability to overstimulation. The author hypothesizes that emotional and cognitive states result and reappear within the analytic encounter. This complicates clinical assessment and technical decisions. The author presents an analytic case and examines (1) the impact of deficit on the development of conflict; (2) the impact of the overwhelmed ego on the mastery of developmental tasks; and (3) the impact of dyslexia on dysgnosia, transference, and analytic process and technique.

Adolescent Executive Dysfunction in Daily Life: Relationships to Risks, Brain Structure and Substance Use

PubMed Central

Clark, Duncan B.; Chung, Tammy; Martin, Christopher S.; Hasler, Brant P.; Fitzgerald, Douglas H.; Luna, Beatriz; Brown, Sandra A.; Tapert, Susan F.; Brumback, Ty; Cummins, Kevin; Pfefferbaum, Adolf; Sullivan, Edith V.; Pohl, Kilian M.; Colrain, Ian M.; Baker, Fiona C.; De Bellis, Michael D.; Nooner, Kate B.; Nagel, Bonnie J.

2017-01-01

During adolescence, problems reflecting cognitive, behavioral and affective dysregulation, such as inattention and emotional dyscontrol, have been observed to be associated with substance use disorder (SUD) risks and outcomes. Prior studies have typically been with small samples, and have typically not included comprehensive measurement of executive dysfunction domains. The relationships of executive dysfunction in daily life with performance based testing of cognitive skills and structural brain characteristics, thought to be the basis for executive functioning, have not been definitively determined. The aims of this study were to determine the relationships between executive dysfunction in daily life, measured by the Behavior Rating Inventory of Executive Function (BRIEF), cognitive skills and structural brain characteristics, and SUD risks, including a global SUD risk indicator, sleep quality, and risky alcohol and cannabis use. In addition to bivariate relationships, multivariate models were tested. The subjects (n = 817; ages 12 through 21) were participants in the National Consortium on Alcohol and Neurodevelopment in Adolescence (NCANDA) study. The results indicated that executive dysfunction was significantly related to SUD risks, poor sleep quality, risky alcohol use and cannabis use, and was not significantly related to cognitive skills or structural brain characteristics. In multivariate models, the relationship between poor sleep quality and risky substance use was mediated by executive dysfunction. While these cross-sectional relationships need to be further examined in longitudinal analyses, the results suggest that poor sleep quality and executive dysfunction may be viable preventive intervention targets to reduce adolescent substance use. PMID:29180956

The gut in trauma.

PubMed

Patel, Jayshil J; Rosenthal, Martin D; Miller, Keith R; Martindale, Robert G

2016-08-01

The purpose of this review is to describe established and emerging mechanisms of gut injury and dysfunction in trauma, describe emerging strategies to improve gut dysfunction, detail the effect of trauma on the gut microbiome, and describe the gut-brain connection in traumatic brain injury. Newer data suggest intraluminal contents, pancreatic enzymes, and hepatobiliary factors disrupt the intestinal mucosal layer. These mechanisms serve to perpetuate the inflammatory response leading to multiple organ dysfunction syndrome (MODS). To date, therapies to mitigate acute gut dysfunction have included enteral nutrition and immunonutrition; emerging therapies aimed to intestinal mucosal layer disruption, however, include protease inhibitors such as tranexamic acid, parenteral nutrition-supplemented bombesin, and hypothermia. Clinical trials to demonstrate benefit in humans are needed before widespread applications can be recommended. Despite resuscitation, gut dysfunction promotes distant organ injury. In addition, postresuscitation nosocomial and iatrogenic 'hits' exaggerate the immune response, contributing to MODS. This was a provocative concept, suggesting infectious and noninfectious causes of inflammation may trigger, heighten, and perpetuate an inflammatory response culminating in MODS and death. Emerging evidence suggests posttraumatic injury mechanisms, such as intestinal mucosal disruption and shifting of the gut microbiome to a pathobiome. In addition, traumatic brain injury activates the gut-brain axis and increases intestinal permeability.

Increased susceptibility to proactive interference in adults with dyslexia?

PubMed

Bogaerts, Louisa; Szmalec, Arnaud; Hachmann, Wibke M; Page, Mike P A; Woumans, Evy; Duyck, Wouter

2015-01-01

Recent findings show that people with dyslexia have an impairment in serial-order memory. Based on these findings, the present study aimed to test the hypothesis that people with dyslexia have difficulties dealing with proactive interference (PI) in recognition memory. A group of 25 adults with dyslexia and a group of matched controls were subjected to a 2-back recognition task, which required participants to indicate whether an item (mis)matched the item that had been presented 2 trials before. PI was elicited using lure trials in which the item matched the item in the 3-back position instead of the targeted 2-back position. Our results demonstrate that the introduction of lure trials affected 2-back recognition performance more severely in the dyslexic group than in the control group, suggesting greater difficulty in resisting PI in dyslexia.

Developmental dyslexia: predicting individual risk.

PubMed

Thompson, Paul A; Hulme, Charles; Nash, Hannah M; Gooch, Debbie; Hayiou-Thomas, Emma; Snowling, Margaret J

2015-09-01

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. 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. 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. 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. © 2015 The Authors. Journal of Child Psychology and Psychiatry published by John Wiley & Sons Ltd on behalf of Association for Child and Adolescent Mental Health.

Minimal Brain Dysfunction: Associations with Perinatal Complications.

ERIC Educational Resources Information Center

Nichols, Paul L.

Examined with over 28,000 7-year-old children whose mothers registered for prenatal care was the relationship between perinatal complications and such characteristics as poor school achievement, hyperactivity, and neurological soft signs associated with the diagnosis of minimal brain dysfunction (MBD). Ten perinatal antecedents were studied:…

Occurrence of oculomotor dysfunctions in acquired brain injury: a retrospective analysis.

PubMed

Ciuffreda, Kenneth J; Kapoor, Neera; Rutner, Daniella; Suchoff, Irwin B; Han, M E; Craig, Shoshana

2007-04-01

The purpose of this retrospective study was to determine the frequency of occurrence of oculomotor dysfunctions in a sample of ambulatory outpatients who have acquired brain injury (ABI), either traumatic brain injury (TBI) or cerebrovascular accident (CVA), with associated vision symptoms. Medical records of 220 individuals with either TBI (n = 160) or CVA (n = 60) were reviewed retrospectively. This was determined by a computer-based query spanning the years 2000 through 2003, for the frequency of occurrence of oculomotor dysfunctions including accommodation, version, vergence, strabismus, and cranial nerve (CN) palsy. The majority of individuals with either TBI (90%) or CVA (86.7%) manifested an oculomotor dysfunction. Accommodative and vergence deficits were most common in the TBI subgroup, whereas strabismus and CN palsy were most common in the CVA subgroup. The frequency of occurrence of versional deficits was similar in each diagnostic subgroup. These new findings should alert the clinician to the higher frequency of occurrence of oculomotor dysfunctions in these populations and the associated therapeutic, rehabilitative, and quality-of-life implications.

Dyslexia and early intervention: what did we learn from the Dutch Dyslexia Programme?

PubMed

van der Leij, Aryan

2013-11-01

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. Copyright © 2013 John Wiley & Sons, Ltd.

Genetic analysis of dyslexia candidate genes in the European cross-linguistic NeuroDys cohort.

PubMed

Becker, Jessica; Czamara, Darina; Scerri, Tom S; Ramus, Franck; Csépe, Valéria; Talcott, Joel B; Stein, John; Morris, Andrew; Ludwig, Kerstin U; Hoffmann, Per; Honbolygó, Ferenc; Tóth, Dénes; Fauchereau, Fabien; Bogliotti, Caroline; Iannuzzi, Stéphanie; Chaix, Yves; Valdois, Sylviane; Billard, Catherine; George, Florence; Soares-Boucaud, Isabelle; Gérard, Christophe-Loïc; van der Mark, Sanne; Schulz, Enrico; Vaessen, Anniek; Maurer, Urs; Lohvansuu, Kaisa; Lyytinen, Heikki; Zucchelli, Marco; Brandeis, Daniel; Blomert, Leo; Leppänen, Paavo H T; Bruder, Jennifer; Monaco, Anthony P; Müller-Myhsok, Bertram; Kere, Juha; Landerl, Karin; Nöthen, Markus M; Schulte-Körne, Gerd; Paracchini, Silvia; Peyrard-Janvid, Myriam; Schumacher, Johannes

2014-05-01

Dyslexia is one of the most common childhood disorders with a prevalence of around 5-10% in school-age children. Although an important genetic component is known to have a role in the aetiology of dyslexia, we are far from understanding the molecular mechanisms leading to the disorder. Several candidate genes have been implicated in dyslexia, including DYX1C1, DCDC2, KIAA0319, and the MRPL19/C2ORF3 locus, each with reports of both positive and no replications. We generated a European cross-linguistic sample of school-age children - the NeuroDys cohort - that includes more than 900 individuals with dyslexia, sampled with homogenous inclusion criteria across eight European countries, and a comparable number of controls. Here, we describe association analysis of the dyslexia candidate genes/locus in the NeuroDys cohort. We performed both case-control and quantitative association analyses of single markers and haplotypes previously reported to be dyslexia-associated. Although we observed association signals in samples from single countries, we did not find any marker or haplotype that was significantly associated with either case-control status or quantitative measurements of word-reading or spelling in the meta-analysis of all eight countries combined. Like in other neurocognitive disorders, our findings underline the need for larger sample sizes to validate possibly weak genetic effects.

Academic Achievement of University Students with Dyslexia.

PubMed

Olofsson, Åke; Taube, Karin; Ahl, Astrid

2015-11-01

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. Copyright © 2015 John Wiley & Sons, Ltd.

Location negative priming effects in children with developmental dyslexia: An event-related potential study.

PubMed

Ma, Yujun; Wang, Enguo; Yuan, Tian; Zhao, Guo Xiang

2016-08-01

As the reading process is inseparable from working memory, inhibition, and other higher cognitive processes, the deep cognitive processing defects that are associated with dyslexia may be due to defective distraction inhibition systems. In this study, we used event-related potential technology to explore the source of negative priming effects in children with developmental dyslexia and in a group of healthy children for comparison. We found that the changes in the average response times in the negative priming and control conditions were consistent across the two groups, while the negative priming effects differed significantly between the groups. The magnitude of the negative priming effect was significantly different between the two groups, with the magnitude being significantly higher in the control group than it was in the developmental dyslexia group. These results indicate that there are deficits in distraction inhibition in children with developmental dyslexia. In terms of the time course of processing, inhibition deficits in the dyslexia group appeared during early-stage cognition selection and lasted through the response selection phase. Regarding the cerebral cortex locations, early-stage cognition selection was mainly located in the parietal region, while late-stage response selection was mainly located in the frontal and central regions. The results of our study may help further our understanding of the intrinsic causes of developmental dyslexia. Copyright © 2016 Elsevier Ltd. All rights reserved.

Incorporating virtual reality graphics with brain imaging for assessment of sport-related concussions.

PubMed

Slobounov, Semyon; Sebastianelli, Wayne; Newell, Karl M

2011-01-01

There is a growing concern that traditional neuropsychological (NP) testing tools are not sensitive to detecting residual brain dysfunctions in subjects suffering from mild traumatic brain injuries (MTBI). Moreover, most MTBI patients are asymptomatic based on anatomical brain imaging (CT, MRI), neurological examinations and patients' subjective reports within 10 days post-injury. Our ongoing research has documented that residual balance and visual-kinesthetic dysfunctions along with its underlying alterations of neural substrates may be detected in "asymptomatic subjects" by means of Virtual Reality (VR) graphics incorporated with brain imaging (EEG) techniques.

Self-Efficacy in Undergraduate Students with Dyslexia: A Mixed Methods Investigation

ERIC Educational Resources Information Center

Stagg, Steven D.; Eaton, Elizabeth; Sjoblom, Amanda M.

2018-01-01

It may be thought that gaining a place at university confers self-belief on students with dyslexia; after all, they have succeeded in their academic studies. Our research explored self-efficacy beliefs in university students with and without dyslexia. An Academic Self-Efficacy Scale and a Sources of Academic Self-Efficacy Scale were completed by…

Writing in Dyslexia: Product and Process

ERIC Educational Resources Information Center

Morken, Froydis; Helland, Turid

2013-01-01

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…

Evaluation of Ocular Movements in Patients with Dyslexia

ERIC Educational Resources Information Center

Vagge, Aldo; Cavanna, Margherita; Traverso, Carlo Enrico; Iester, Michele

2015-01-01

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…

Rapid Processing of Letters, Digits and Symbols: What Purely Visual-Attentional Deficit in Developmental Dyslexia?

ERIC Educational Resources Information Center

Ziegler, Johannes C.; Pech-Georgel, Catherine; Dufau, Stephane; Grainger, Jonathan

2010-01-01

Visual-attentional theories of dyslexia predict deficits for dyslexic children not only for the perception of letter strings but also for non-alphanumeric symbol strings. This prediction was tested in a two-alternative forced-choice paradigm with letters, digits, and symbols. Children with dyslexia showed significant deficits for letter and digit…

Phonological and Sensory Short-Term Memory Are Correlates and Both Affected in Developmental Dyslexia

ERIC Educational Resources Information Center

Laasonen, Marja; Virsu, Veijo; Oinonen, Suvi; Sandbacka, Mirja; Salakari, Anita; Service, Elisabet

2012-01-01

We investigated whether poor short-term memory (STM) in developmental dyslexia affects the processing of sensory stimulus sequences in addition to phonological material. STM for brief binary non-verbal stimuli (light flashes, tone bursts, finger touches, and their crossmodal combinations) was studied in 20 Finnish adults with dyslexia and 24…

Dyslexia and Dyscalculia: Two Learning Disorders with Different Cognitive Profiles

ERIC Educational Resources Information Center

Landerl, Karin; Fussenegger, Barbara; Moll, Kristina; Willburger, Edith

2009-01-01

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…

Expanding Horizons for Students with Dyslexia in the 21st Century: Universal Design and Mobile Technology

ERIC Educational Resources Information Center

Reid, Gavin; Strnadova, Iva; Cumming, Therese

2013-01-01

This paper discusses the role of mobile technology in supporting people with dyslexia within the theoretical framework of Universal Design for Learning. The authors discuss how students with dyslexia can use mobile technology to address a diverse range of academic needs (such as reading, composing text, notetaking, metacognition and studying…

Reading and Spelling Gains Following One Year of Orton-Gillingham Intervention in Singaporean Students with Dyslexia

ERIC Educational Resources Information Center

Lim, Lois; Oei, Adam C.

2015-01-01

Despite the widespread use of Orton-Gillingham (OG) based approaches to dyslexia remediation, empirical support documenting its effectiveness is lacking. Recently, Chia and Houghton demonstrated the effectiveness of the OG approach for remediation of dyslexia in Singapore. As a conceptual replication and extension of that research, we report…

Delayed Early Vocabulary Development in Children at Family Risk of Dyslexia

ERIC Educational Resources Information Center

van Viersen, Sietske; de Bree, Elise H.; Verdam, Mathilde; Krikhaar, Evelien; Maassen, Ben; van der Leij, Aryan; de Jong, Peter F.

2017-01-01

Purpose: This study aimed to gain more insight into the relation between vocabulary and reading acquisition by examining early growth trajectories in the vocabulary of children at family risk (FR) of dyslexia longitudinally. Method: The sample included 212 children from the Dutch Dyslexia Program with and without an FR. Parents reported on their…

Neuropsychological Profile on the WISC-IV of French Children with Dyslexia

ERIC Educational Resources Information Center

De Clercq-Quaegebeur, Maryse; Casalis, Severine; Lemaitre, Marie-Pierre; Bourgois, Beatrice; Getto, Marie; Vallee, Louis

2010-01-01

This study examined the pattern of results on the "Wechsler Intelligence Scale for Children" (WISC-IV; French version) for 60 French children with dyslexia, from 8 to 16 years of age. Although use of WISC-III failed to clearly identify typical profiles and cognitive deficits in dyslexia, WISC-IV offers an opportunity to reach these…

Assessing Dyslexia in Higher Education: The "York Adult Assessment Battery-Revised"

ERIC Educational Resources Information Center

Warmington, Meesha; Stothard, Susan E.; Snowling, Margaret J.

2013-01-01

Although there are a number of standardised measures to assess dyslexia in children, there are comparatively fewer instruments suitable for the assessment of dyslexia in adults. Given the growing number of students entering UK higher education institutions, there is a need to develop reliable tools for assessing the additional needs of those with…

Putative Risk Factors in Developmental Dyslexia: A Case-Control Study of Italian Children

ERIC Educational Resources Information Center

Mascheretti, Sara; Marino, Cecilia; Simone, Daniela; Quadrelli, Ermanno; Riva, Valentina; Cellino, Maria Rosaria; Maziade, Michel; Brombin, Chiara; Battaglia, Marco

2015-01-01

Although dyslexia runs in families, several putative risk factors that cannot be immediately identified as genetic predict reading disability. Published studies analyzed one or a few risk factors at a time, with relatively inconsistent results. To assess the contribution of several putative risk factors to the development of dyslexia, we conducted…

Academic Interventions for Children with Dyslexia Who Have Phonological Core Deficits. ERIC Digest E539.

ERIC Educational Resources Information Center

Frost, Julie A.; Emery, Michael J.

This digest presents basic information for those providing educational services to children with dyslexia who have phonological core deficits. First it provides a brief overview, noting the incidence of dyslexia and the large number of these children with phonological deficits which result in far less academic progress than experienced by other…

Tip-of-the-Tongue and Word Retrieval Deficits in Dyslexia

ERIC Educational Resources Information Center

Hanly, Sarah; Vandenberg, Brian

2010-01-01

Tip-of-the-tongue (TOT) responses on a picture-naming task were used to test the hypothesis that dyslexia involves phonological, but not semantic, processing deficits. Participants included 16 children with dyslexia and 31 control children between 8 and 10 years of age who did not differ in receptive vocabulary. As hypothesized, children with…

Dorsal Stream Deficits Suggest Hidden Dyslexia among Deaf Poor Readers: Correlated Evidence from Reduced Perceptual Speed and Elevated Coherent Motion Detection Thresholds

ERIC Educational Resources Information Center

Samar, V.J.; Parasnis, I.

2005-01-01

Prelingual deafness and developmental dyslexia have confounding developmental effects on reading acquisition. Therefore, standard reading assessment methods for diagnosing dyslexia in hearing people are ineffective for use with deaf people. Recently, Samar, Parasnis, and Berent (2002) reported visual evoked potential evidence that deaf poor…

Auditory Processing Interventions and Developmental Dyslexia: A Comparison of Phonemic and Rhythmic Approaches

ERIC Educational Resources Information Center

Thomson, Jennifer M.; Leong, Victoria; Goswami, Usha

2013-01-01

The purpose of this study was to compare the efficacy of two auditory processing interventions for developmental dyslexia, one based on rhythm and one based on phonetic training. Thirty-three children with dyslexia participated and were assigned to one of three groups (a) a novel rhythmic processing intervention designed to highlight auditory…

The Development of Reading Accuracy and Reading Rate during Treatment of Dyslexia

ERIC Educational Resources Information Center

Tijms, Jurgen

2007-01-01

Two experiments were conducted to provide a window on the processes by which the accuracy and rate of reading develop during psycholinguistic treatment for dyslexia. In experiment 1,140 children with dyslexia followed a treatment method that presented them with a learning system that clarifies the basic elements and operations by which one's…

Visual Search Deficits Are Independent of Magnocellular Deficits in Dyslexia

ERIC Educational Resources Information Center

Wright, Craig M.; Conlon, Elizabeth G.; Dyck, Murray

2012-01-01

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…

Dyslexie Font Does Not Benefit Reading in Children with or without Dyslexia

ERIC Educational Resources Information Center

Kuster, Sanne M.; van Weerdenburg, Marjolijn; Gompel, Marjolein; Bosman, Anna M. T.

2018-01-01

In two experiments, the claim was tested that the font "Dyslexie", specifically designed for people with dyslexia, eases reading performance of children with (and without) dyslexia. Three questions were investigated. (1) Does the Dyslexie font lead to faster and/or more accurate reading? (2) Do children have a preference for the Dyslexie…

A Facilitation of Dyslexia through a Remediation of Shakespeare's Text

ERIC Educational Resources Information Center

Whitfield, Petronilla

2016-01-01

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…

Sight Word and Phonics Training in Children with Dyslexia

ERIC Educational Resources Information Center

McArthur, Genevieve; Castles, Anne; Kohnen, Saskia; Larsen, Linda; Jones, Kristy; Anandakumar, Thushara; Banales, Erin

2015-01-01

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…

Knowledge and Beliefs about Developmental Dyslexia in Pre-Service and In-Service Spanish-Speaking Teachers

ERIC Educational Resources Information Center

Soriano-Ferrer, Manuel; Echegaray-Bengoa, Joyce; Joshi, R. Malathesa

2016-01-01

The present study investigated knowledge, misconceptions, and lack of information about dyslexia among pre-service (PST) and in-service (IST) Spanish-speaking teachers in Spain and Peru. Two hundred and forty-six pre-service teachers and 267 in-service teachers completed the Knowledge and Beliefs about Developmental Dyslexia Scale (KBDDS).…

What's in a Name? Students with Dyslexia: Their Use of Metaphor in Making Sense of Their Disability

ERIC Educational Resources Information Center

Burden, Robert; Burdett, Julia

2007-01-01

Research and practice involving children and adults with dyslexia has tended to focus on identifying difficulties in developing literacy skills and associated cognitive variables. Comparatively few investigations have focused on affective factors or on finding ways of enabling those with dyslexia to express their own attitudes, thoughts and…

Dyslexia in Chinese Language: An Overview of Research and Practice

ERIC Educational Resources Information Center

Chung, Kevin K. H.; Ho, Connie S. H.

2010-01-01

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…

Exploring Teacher Knowledge about Dyslexia and Teacher Efficacy in the Inclusive Classroom: A Multiple Case Study

ERIC Educational Resources Information Center

Sicherer, Mati

2014-01-01

Researchers have found that teachers seem to lack information about dyslexia which can influence teaching efficacy and behavior. Because inclusion has caused children with dyslexia to spend the majority of their day in general education classrooms, general education teachers are mainly responsible for educating these students. These teachers must…

Understanding Dyslexia and Its Instructional Implications: A Case to Support Intense Intervention

ERIC Educational Resources Information Center

Gray, Erika S.

2008-01-01

Dyslexia is a congenital disorder characterized by unexpected difficulties in learning to read and spell in relation to one's verbal intelligence, motivation, and educational opportunities (Aylward et al., 2003; Morgan, 1896). Because dyslexia can affect 1.5-5% of the population (Aylward et al., 2003; Vellutino et al., 1996), understanding how to…

Implicit Learning of Non-Linguistic and Linguistic Regularities in Children with Dyslexia

ERIC Educational Resources Information Center

Nigro, Luciana; Jiménez-Fernández, Gracia; Simpson, Ian C.; Defior, Sylvia

2016-01-01

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…

The Nature of Developmental Dyslexia in a Transparent Orthography

ERIC Educational Resources Information Center

Verhoeven, Ludo; Keuning, Jos

2018-01-01

The present study aimed to explore the nature of developmental dyslexia in a language considered to have a transparent orthography, namely, Dutch. We assessed the accuracy and efficiency of decoding words and pseudowords with four lengths as well as three types of phonological ability in 2,760 typical children and 397 peers with dyslexia across…

English Word Reading Difficulties and Orthographic Processing Weaknesses in Chinese English Bilingual Adolescents with Dyslexia

ERIC Educational Resources Information Center

Tong, Xiuhong; McBride, Catherine

2017-01-01

Is dyslexia in Chinese for Chinese-English bilinguals associated with difficulties in reading English, given differences in L1 and L2 orthographies? Among 11 Hong Kong Chinese adolescents with dyslexia, who were diagnosed by professional psychologists using the diagnostic criteria set out in a standardized test, and 14 adolescents without…

Temporal Order Judgment in Dyslexia--Task Difficulty or Temporal Processing Deficiency?

ERIC Educational Resources Information Center

Skottun, Bernt C.; Skoyles, John R.

2010-01-01

Dyslexia has been widely held to be associated with deficient temporal processing. It is, however, not established that the slower visual processing of dyslexic readers is not a secondary effect of task difficulty. To illustrate this we re-analyze data from Liddle et al. (2009) who studied temporal order judgment in dyslexia and plotted the…

Effects of Dyslexia on Postural Control in Adults

ERIC Educational Resources Information Center

Patel, M.; Magnusson, M.; Lush, D.; Gomez, S.; Fransson, P. A.

2010-01-01

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…

A General Audiovisual Temporal Processing Deficit in Adult Readers with Dyslexia

ERIC Educational Resources Information Center

Francisco, Ana A.; Jesse, Alexandra; Groen, Margriet A.; McQueen, James M.

2017-01-01

Purpose: Because reading is an audiovisual process, reading impairment may reflect an audiovisual processing deficit. The aim of the present study was to test the existence and scope of such a deficit in adult readers with dyslexia. Method: We tested 39 typical readers and 51 adult readers with dyslexia on their sensitivity to the simultaneity of…

Neglect Dyslexia: Frequency, Association with Other Hemispatial Neglects, and Lesion Localization

ERIC Educational Resources Information Center

Lee, Byung Hwa; Suh, Mee Kyung; Kim, Eun-Joo; Seo, Sang Won; Choi, Kyung Mook; Kim, Gyeong-Moon; Chung, Chin-Sang; Heilman, Kenneth M.; Na, Duk L.

2009-01-01

Patients with right hemisphere injury often omit or misread words on the left side of a page or the beginning letters of single words (neglect dyslexia). Our study involving a large sample of acute right hemisphere stroke investigated (1) the frequency of neglect dyslexia (ND), (2) the association between ND and other types of contralesional…

The Role of Sensorimotor Impairments in Dyslexia: A Multiple Case Study of Dyslexic Children

ERIC Educational Resources Information Center

White, Sarah; Milne, Elizabeth; Rosen, Stuart; Hansen, Peter; Swettenham, John; Frith, Uta; Ramus, Franck

2006-01-01

This study attempts to investigate the role of sensorimotor impairments in the reading disability that characterizes dyslexia. Twenty-three children with dyslexia were compared to 22 control children, matched for age and non-verbal intelligence, on tasks assessing literacy as well as phonological, visual, auditory and motor abilities. The dyslexic…

Dyslexia: A Wider View. The Contribution of an Ecological Paradigm to Current Issues.

ERIC Educational Resources Information Center

Poole, Jennifer

2003-01-01

Dyslexia issues such as its existence, definition, and medical versus educational construction have been framed by the scientific paradigm. Reframing using an ecological perspective allows assessment focused on whole-school approaches and sociocultural factors. It also enables the use of predictive research and a view of dyslexia as more than a…

Evidence-Based Reading and Writing Assessment for Dyslexia in Adolescents and Young Adults

ERIC Educational Resources Information Center

Nielsen, Kathleen; Abbott, Robert; Griffin, Whitney; Lott, Joe; Raskind, Wendy; Berninger, Virginia W.

2016-01-01

The same working memory and reading and writing achievement phenotypes (behavioral markers of genetic variants) validated in prior research with younger children and older adults in a multi-generational family genetics study of dyslexia were used to study 81 adolescent and young adults (ages 16 to 25) from that study. Dyslexia is impaired word…

Reading under the Skin: Physiological Activation during Reading in Children with Dyslexia and Typical Readers

ERIC Educational Resources Information Center

Tobia, Valentina; Bonifacci, Paola; Ottaviani, Cristina; Borsato, Thomas; Marzocchi, Gian Marco

2016-01-01

The aim of this study was to investigate physiological activation during reading and control tasks in children with dyslexia and typical readers. Skin conductance response (SCR) recorded during four tasks involving reading aloud, reading silently, and describing illustrated stories aloud and silently was compared for children with dyslexia (n =…

Students' Experiences of Academic Success with Dyslexia: A Call for Alternative Intervention

ERIC Educational Resources Information Center

Soni, Anita

2017-01-01

This article describes a small-scale study exploring the perspectives of five undergraduate students with dyslexia. Semi-structured interviews were conducted in two universities in the UK. The interviews explored participants' perceptions of their dyslexia label and how it had affected their academic success. The aim of the research was to…

The Educational, Social and Emotional Experiences of Students with Dyslexia: The Perspective of Postsecondary Education Students

ERIC Educational Resources Information Center

Doikou-Avlidou, Maro

2015-01-01

The present study aimed at exploring the educational, social and emotional experiences of individuals with dyslexia both during school and tertiary education. For this purpose, semi-structured interviews were conducted with ten Greek students with dyslexia who were enrolled in higher education institutions. The data analysis was carried out with…

Examination of the Double-Deficit Hypothesis with Adolescents and Young Adults with Dyslexia

ERIC Educational Resources Information Center

Nelson, Jason M.

2015-01-01

The double-deficit hypothesis (DDH) of the developmental dyslexias (Wolf and Bowers, "Journal of Educational Psychology", 91, 415-438, 1999) was investigated with 149 adolescents and young adults (age range?=?16 to 24 years) with dyslexia. Confirmatory factor analysis indicated that a two-factor model with separate naming speed (NS) and…

Hemispheric, Attentional, and Processing Speed Factors in the Treatment of Developmental Dyslexia

ERIC Educational Resources Information Center

Lorusso, Maria Luisa; Facoetti, Andrea; Molteni, Massimo

2004-01-01

Aim of the study is to analyze the contributions of hemispheric, attentional, and processing speed factors to the effects of neuropsychological treatment of developmental dyslexia. Four groups of dyslexic children (M-type dyslexia) were treated over a period of four months. A first group (n=9) underwent Bakker's Hemisphere-Specific Stimulation,…

Pupillary and Heart Rate Reactivity in Children with Minimal Brain Dysfunction

ERIC Educational Resources Information Center

Zahn, Theodore P.; And Others

1978-01-01

In an attempt to replicate and extend previous findings on autonomic arousal and responsivity in children with minimal brain dysfunction (MBD), pupil size, heart rate, skin conductance, and skin temperature were recorded from 32 MBD and 45 control children (6-13 years old). (Author/CL)

Anterior Temporal Lobe Connectivity Correlates with Functional Outcome after Aphasic Stroke

ERIC Educational Resources Information Center

Warren, Jane E.; Crinion, Jennifer T.; Ralph, Matthew A. Lambon; Wise, Richard J. S.

2009-01-01

Focal brain lesions are assumed to produce language deficits by two basic mechanisms: local cortical dysfunction at the lesion site, and remote cortical dysfunction due to disruption of the transfer and integration of information between connected brain regions. However, functional imaging studies investigating language outcome after aphasic…

Relations between Neurological Aberrations and Psychological Dysfunctions in Children with Serious Language Problems.

ERIC Educational Resources Information Center

Bo, Ola O.; And Others

1992-01-01

Relationships between neuropsychological aberrations and psychological dysfunction were studied for 20 Swedish children (average age around 10 years at first testing) with serious language problems through (1) electroencephalography; (2) brain stem response audiometry; (3) magnetic resonance imaging; and (4) brain electric activity mapping by…

Rapid Naming in Brazilian Students with Dyslexia and Attention Deficit Hyperactivity Disorder

PubMed Central

Alves, Luciana Mendonça; Siqueira, Cláudia M.; Ferreira, Maria do Carmo Mangelli; Alves, Juliana Flores Mendonça; Lodi, Débora F.; Bicalho, Lorena; Celeste, Letícia C.

2016-01-01

Introduction: The effective development of reading and writing skills requires the concerted action of several abilities, one of which is phonological processing. One of the main components of phonological processing is rapid automatized naming (RAN)—the ability to identify and recognize a given item by the activation and concomitant articulation of its name. Objective: To assess the RAN performance of schoolchildren with dyslexia and attention deficit hyperactivity disorder (ADHD) compared with their peers. Methods: In total, 70 schoolchildren aged between 8 and 11 years participated in the study. Of these, 16 children had a multiprofessional diagnosis of ADHD while 14 were diagnosed with dyslexia. Matched with these groups, 40 schoolchildren with no history of developmental impairments were also evaluated. The RAN test was administered to assess the length of time required to name a series of familiar visual stimuli. The statistical analysis was conducted using measures of descriptive statistics and the 2-sample t-test at the 5% significance level. Results: The performance of the group with dyslexia was inferior to that of the control group in all tasks and the ADHD group had inferior performance for color and letters-naming tasks. The schoolchildren with dyslexia and those with ADHD showed very similar response times. Age was an important variable to be analyzed separately. As they aged, children with typical language development had fast answers on colors and digits tasks while children with dyslexia or ADHD did not show improvement with age. Conclusions: The schoolchildren with dyslexia took longer to complete all tasks and ADHD took longer to complete digits and objects tasks in comparison to their peers with typical development. This ability tended to improve with age, which was not the case, however, with schoolchildren who had ADHD or dyslexia. PMID:26858672

Visual and auditory perception in preschool children at risk for dyslexia.

PubMed

Ortiz, Rosario; Estévez, Adelina; Muñetón, Mercedes; Domínguez, Carolina

2014-11-01

Recently, there has been renewed interest in perceptive problems of dyslexics. A polemic research issue in this area has been the nature of the perception deficit. Another issue is the causal role of this deficit in dyslexia. Most studies have been carried out in adult and child literates; consequently, the observed deficits may be the result rather than the cause of dyslexia. This study addresses these issues by examining visual and auditory perception in children at risk for dyslexia. We compared children from preschool with and without risk for dyslexia in auditory and visual temporal order judgment tasks and same-different discrimination tasks. Identical visual and auditory, linguistic and nonlinguistic stimuli were presented in both tasks. The results revealed that the visual as well as the auditory perception of children at risk for dyslexia is impaired. The comparison between groups in auditory and visual perception shows that the achievement of children at risk was lower than children without risk for dyslexia in the temporal tasks. There were no differences between groups in auditory discrimination tasks. The difficulties of children at risk in visual and auditory perceptive processing affected both linguistic and nonlinguistic stimuli. Our conclusions are that children at risk for dyslexia show auditory and visual perceptive deficits for linguistic and nonlinguistic stimuli. The auditory impairment may be explained by temporal processing problems and these problems are more serious for processing language than for processing other auditory stimuli. These visual and auditory perceptive deficits are not the consequence of failing to learn to read, thus, these findings support the theory of temporal processing deficit. Copyright © 2014 Elsevier Ltd. All rights reserved.

Reading Performance Is Enhanced by Visual Texture Discrimination Training in Chinese-Speaking Children with Developmental Dyslexia

PubMed Central

Meng, Xiangzhi; Lin, Ou; Wang, Fang; Jiang, Yuzheng; Song, Yan

2014-01-01

Background High order cognitive processing and learning, such as reading, interact with lower-level sensory processing and learning. Previous studies have reported that visual perceptual training enlarges visual span and, consequently, improves reading speed in young and old people with amblyopia. Recently, a visual perceptual training study in Chinese-speaking children with dyslexia found that the visual texture discrimination thresholds of these children in visual perceptual training significantly correlated with their performance in Chinese character recognition, suggesting that deficits in visual perceptual processing/learning might partly underpin the difficulty in reading Chinese. Methodology/Principal Findings To further clarify whether visual perceptual training improves the measures of reading performance, eighteen children with dyslexia and eighteen typically developed readers that were age- and IQ-matched completed a series of reading measures before and after visual texture discrimination task (TDT) training. Prior to the TDT training, each group of children was split into two equivalent training and non-training groups in terms of all reading measures, IQ, and TDT. The results revealed that the discrimination threshold SOAs of TDT were significantly higher for the children with dyslexia than for the control children before training. Interestingly, training significantly decreased the discrimination threshold SOAs of TDT for both the typically developed readers and the children with dyslexia. More importantly, the training group with dyslexia exhibited significant enhancement in reading fluency, while the non-training group with dyslexia did not show this improvement. Additional follow-up tests showed that the improvement in reading fluency is a long-lasting effect and could be maintained for up to two months in the training group with dyslexia. Conclusion/Significance These results suggest that basic visual perceptual processing/learning and reading ability in Chinese might at least partially rely on overlapping mechanisms. PMID:25247602

Dyscalculia and the Calculating Brain.

PubMed

Rapin, Isabelle

2016-08-01

Dyscalculia, like dyslexia, affects some 5% of school-age children but has received much less investigative attention. In two thirds of affected children, dyscalculia is associated with another developmental disorder like dyslexia, attention-deficit disorder, anxiety disorder, visual and spatial disorder, or cultural deprivation. Infants, primates, some birds, and other animals are born with the innate ability, called subitizing, to tell at a glance whether small sets of scattered dots or other items differ by one or more item. This nonverbal approximate number system extends mostly to single digit sets as visual discrimination drops logarithmically to "many" with increasing numerosity (size effect) and crowding (distance effect). Preschoolers need several years and specific teaching to learn verbal names and visual symbols for numbers and school agers to understand their cardinality and ordinality and the invariance of their sequence (arithmetic number line) that enables calculation. This arithmetic linear line differs drastically from the nonlinear approximate number system mental number line that parallels the individual number-tuned neurons in the intraparietal sulcus in monkeys and overlying scalp distribution of discrete functional magnetic resonance imaging activations by number tasks in man. Calculation is a complex skill that activates both visual and spatial and visual and verbal networks. It is less strongly left lateralized than language, with approximate number system activation somewhat more right sided and exact number and arithmetic activation more left sided. Maturation and increasing number skill decrease associated widespread non-numerical brain activations that persist in some individuals with dyscalculia, which has no single, universal neurological cause or underlying mechanism in all affected individuals. Copyright © 2016 Elsevier Inc. All rights reserved.

Early communicative gestures and play as predictors of language development in children born with and without family risk for dyslexia.

PubMed

Unhjem, Astrid; Eklund, Kenneth; Nergård-Nilssen, Trude

2014-08-01

The present study investigated early communicative gestures, play, and language skills in children born with family risk for dyslexia (FR) and a control group of children without this inheritable risk at ages 12, 15, 18, and 24 months. Participants were drawn from the Tromsø Longitudinal study of Dyslexia (TLD) which follows children's cognitive and language development from age 12 months through Grade 2 in order to identify early markers of developmental dyslexia. Results showed that symbolic play and parent reported play at age 12 months and communicative gestures at age 15 months explained 61% of the variance in productive language at 24 months in the FR group. These early nonlinguistic measures seem to be potentially interesting markers of later language development in children born at risk for dyslexia. © 2014 Scandinavian Psychological Associations and John Wiley & Sons Ltd.

Quantitative assessment of drawing tests in children with dyslexia and dysgraphia.

PubMed

Galli, Manuela; Cimolin, Veronica; Stella, Giacomo; De Pandis, Maria Francesca; Ancillao, Andrea; Condoluci, Claudia

2018-05-07

Drawing tests in children diagnosed with dyslexia and dysgraphia were quantitatively compared. Fourteen children with dysgraphia, 19 with dyslexia and 13 normally developing were asked to copy 3 figures: a circle, a square and a cross. An optoelectronic system allowed the acquisition of the drawing track in three-dimensions. The participants' head position and upper limb movements were measured as well. A set of parameters including movement duration, velocity, length of the trace, Range of Motion of the upper limb, was computed and compared among the 3 groups. Children with dyslexia traced the circle faster than the other groups. In the cross test, dyslexic participants showed a reduced execution time and increased velocity while drawing the horizontal line. Children with dyslexia were also faster in drawing certain sides of square with respect to the other groups. Copyright © 2018 Elsevier B.V. All rights reserved.