There is some evidence for a role of music training in boosting phonological awareness, word segmentation, working memory, as well as reading abilities in children with typical development. Poor ...performance in tasks requiring temporal processing, rhythm perception and sensorimotor synchronization seems to be a crucial factor underlying dyslexia in children. Interestingly, children with dyslexia show deficits in temporal processing, both in language and in music. Within this framework, we test the hypothesis that music training, by improving temporal processing and rhythm abilities, improves phonological awareness and reading skills in children with dyslexia. The study is a prospective, multicenter, open randomized controlled trial, consisting of test, rehabilitation and re-test (ID NCT02316873). After rehabilitation, the music group (N = 24) performed better than the control group (N = 22) in tasks assessing rhythmic abilities, phonological awareness and reading skills. This is the first randomized control trial testing the effect of music training in enhancing phonological and reading abilities in children with dyslexia. The findings show that music training can modify reading and phonological abilities even when these skills are severely impaired. Through the enhancement of temporal processing and rhythmic skills, music might become an important tool in both remediation and early intervention programs.Trial Registration: ClinicalTrials.gov NCT02316873
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.
Many studies report a deficit in working memory in children with Developmental Dyslexia (DD) and Developmental Coordination Disorder (DCD) compared to children with Typical Development (TD). In this ...study, we questioned the working memory profile of children with co-occurring Developmental Dyslexia and Developmental Coordination Disorder (DD-DCD). First, we hypothesized that children with DD would have a more substantial deficit in verbal working memory, while children with DCD would have a more substantial deficit in visuospatial working memory. For the comorbid group, we postulated a deficit in both the verbal and visuospatial domains. Second, we determined whether we could correctly distinguish between the four groups based on their working memory profiles.
47 children with DD, 22 children with DCD, 27 children with DD-DCD, and 42 TD children aged from 7.6 to 12.6 years were tested on the phonological loop, the visuospatial sketchpad, and the central executive using the Digit Span and Wechsler's Block-tapping tests.
Children with DD had a deficit in verbal working memory including a specific deficit in the phonological loop and children with DCD had a deficit in visuospatial working memory. Comorbid children had poorer performance in verbal working memory (like group with DD) and in visuospatial working memory (like group with DCD). Exploratory cluster analysis resulted in four subgroups: (1) one cluster with good working memory performance made up of most of the TD children; (2) one cluster with a phonological loop deficit mainly made up of the children with DD; (3) one cluster with poor visuospatial working memory capacities mostly made up of the children with DCD (± DD) and (4) one cluster with average performance made up of children from all the groups.
Our results underline the importance of taking comorbidity into account when testing working memory in children with learning disabilities.
The different types of acquired dyslexia described by cognitive neuropsychology have been observed in single-case and case series studies in different languages. However, no multipatient study of ...Spanish-speaking individuals has been reported that uses the same criteria and tasks to identify each participant's acquired dyslexia pattern. In this study, we analyzed participants' performance in three tasks (oral reading of words and nonwords, visual lexical decision with pseudohomophones, and written homophone comprehension) among 16 Spanish-speaking patients with aphasia. We identified 9 patients with acquired phonological dyslexia, 3 with acquired surface dyslexia, and 4 with acquired mixed dyslexia. The results of this research provide more information about the relative frequency of each type of acquired dyslexia in Spanish, which could be used to help design more appropriate treatments for rehabilitation. Identifying which processes have been impaired and which have been preserved will allow professionals to plan more specific interventions.
The Simple View of Reading model suggests that intact language processing and word decoding lead to proficient reading comprehension, with recent studies pointing at executive functions as an ...important component contributing to reading proficiency. Here, we aimed to determine the underlying mechanism(s) for these changes. Participants include 120 8- to 12-year-old children (n = 55 with dyslexia, n = 65 typical readers) trained on an executive functions-based reading program, including pre/postfunctional MRI and behavioral data collection. Across groups, improved word reading was related to stronger functional connections within executive functions and sensory networks. In children with dyslexia, faster and more accurate word reading was related to stronger functional connections within and between sensory networks. These results suggest greater synchronization of brain systems after the intervention, consistent with the "neural noise" hypothesis in children with dyslexia and support the consideration of including executive functions as part of the Simple View of Reading model.
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.
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.
Reading is a complex process involving multiple stages. An impairment in any of these stages may cause distinct types of reading deficits- distinct types of dyslexia. We describe the Malabi, a ...screener to identify deficits in various orthographic, lexical, and sublexical components of the reading process in French. The Malabi utilizes stimuli that are sensitive to different forms of dyslexia, including "attentional dyslexia", as it is traditionally refered to, characterized by letter-to-word binding impairments leading to letter migrations between words (e.g., "bar cat" misread as "bat car"), and "letter-position dyslexia", resulting in letter transpositions within words (e.g., "destiny" misread as "density"). After collecting reading error norms from 138 French middle-school students, we analyzed error types of 16 students with developmental dyslexia. We identified three selective cases of attentional dyslexia and one case of letter-position dyslexia. Further tests confirmed our diagnosis and demonstrate, for the first time, how these dyslexias are manifested in French. These results underscore the significance of recognizing and discussing the existence of multiple dyslexias, both in research contexts when selecting participants for dyslexia studies, and in practical settings where educators and practitioners work with students to develop personalized support. The test and supporting materials are available on Open Science Framework (
https://osf.io/3pgzb/
).
In this study, we concurrently investigated 3 possible causes of dyslexia-a phonological deficit, visual stress, and a reduced visual attention span-in a large population of 164 dyslexic and 118 ...control French children, aged between 8 and 13 years old. We found that most dyslexic children showed a phonological deficit, either in terms of response accuracy (92.1% of the sample), speed (84.8%), or both (79.3%). Deficits in visual attention span, as measured by partial report ability, affected 28.1% of dyslexic participants, all of which also showed a phonological deficit. Visual stress, as measured by subjective reports of visual discomfort, affected 5.5% of dyslexic participants, not more than controls (8.5%). Although phonological variables explained a large amount of variance in literacy skills, visual variables did not explain any additional variance. Finally, children with comorbid phonological and visual deficits did not show more severe reading disability than children with a pure phonological deficit. These results (a) confirm the importance of phonological deficits in dyslexia; (b) suggest that visual attention span may play a role, but a minor one, at least in this population; (c) do not support any involvement of visual stress in dyslexia. Among the factors that may explain some differences with previously published studies, the present sample is characterized by very stringent inclusion criteria, in terms of the severity of reading disability and in terms of exclusion of comorbidities. This may exacerbate the role of phonological deficits to the detriment of other factors playing a role in reading acquisition.
Reading disorders and dyslexia Hulme, Charles; Snowling, Margaret J
Current opinion in pediatrics,
12/2016, Volume:
28, Issue:
6
Journal Article
Peer reviewed
Open access
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.
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