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Journal of Biosciences 2022There is growing interest in understanding the genetic mechanisms underlying dyslexia. Accordingly, the literature on dyslexia is replete with shreds of evidence linking...
There is growing interest in understanding the genetic mechanisms underlying dyslexia. Accordingly, the literature on dyslexia is replete with shreds of evidence linking genes and their genetic markers with dyslexia among different populations. Even though genetic inquiries into dyslexia in the Asian population has gained interest in recent years, very little is known about the genes and their polymorphisms associated with dyslexia in the Indian population. To this end, we provide a systematic literature review that yields a dossier of genetic research that manifests the effect of the genes and their polymorphisms associated with dyslexia susceptibility in the Indian population. We conclude that the polymorphisms of the and genes deserve attention in replication studies on the Indian population in order to gain insight into the genetic etiology of dyslexia.
Topics: Asian People; Dyslexia; Genetic Markers; Genetic Predisposition to Disease; Humans; Nerve Tissue Proteins; Polymorphism, Single Nucleotide
PubMed: 36222135
DOI: No ID Found -
Journal of Learning Disabilities 2023Traditional static tests of reading and reading-related skills offer some ability to predict future reading performance, though such screeners may misclassify children... (Review)
Review
Traditional static tests of reading and reading-related skills offer some ability to predict future reading performance, though such screeners may misclassify children with or at risk of reading disorder (RD). Dynamic assessment (DA) is an alternative approach that measures learning potential and may be less dependent on learning background. A systematic review was carried out to examine the ability of DA to classify children with or at risk of RD. A database search yielded 14 eligible articles assessing DA of decoding, phonological awareness (PA), and working memory (WM). Results suggest that DA explains unique variance in the prediction of later RD status, and although models with a single dynamic predictor sometimes achieved good classification accuracy, this was enhanced somewhat by the addition of static predictors. Higher classification accuracy was found for DA targeting constructs more proximal to reading, particularly decoding, but the predictive power of DA of decoding and PA appeared to wane with increasing age as static measures explained more variance in outcomes. Some evidence emerged that DA provides benefits over static tests for the prediction of RD in bilingual students, though no studies examined outcomes by administration format or orthographic depth. Limitations and suggestions for future work are discussed.
Topics: Child; Humans; Dyslexia; Learning; Awareness; Students; Memory, Short-Term; Phonetics
PubMed: 36017540
DOI: 10.1177/00222194221117510 -
Frontiers in Psychology 2022A growing body of research suggests that children with autism spectrum disorder (ASD) are at risk of reading and learning difficulties. However, there is mixed evidence...
A growing body of research suggests that children with autism spectrum disorder (ASD) are at risk of reading and learning difficulties. However, there is mixed evidence on their weaknesses in different reading components, and little is known about how reading skills characterize in ASD. Thereby, the current study aimed to systematically review the research investigating this function in children with ASD. To this purpose, we reviewed 24 studies that compared (1) children with ASD and children with typical development (TD) in word and nonword reading performance, (2) children with ASD and normative data of word and nonword reading tests, and (3) the results obtained by children with ASD in word and nonword reading tests. Most of the comparisons (62%) contrasting the reading performance of children with ASD and children with TD did not find significant differences between groups in both word and nonword reading. However, all the comparisons that reported standardized results showed that children with ASD had scores that fell within population norms. Regarding the third comparison of interest, about 54% of the studies presented data for both word and nonword reading, but only one study tested the difference between them and showed that children with ASD had higher levels of word than of nonword reading. Despite these results, the heterogeneous and small samples do not allow to draw sound conclusions regarding the strategies that children with ASD use to read words. As consequence, the nature of reading difficulties presented by children with ASD are still unknown, requiring future research conducted with larger and well-characterized samples of ASD and TD, using homogeneous specific tasks designed to assess word reading strategies.
PubMed: 35967660
DOI: 10.3389/fpsyg.2022.930275 -
Brain and Behavior Sep 2022Among the target groups in child and adolescent psychiatry, transcranial direct current stimulation (tDCS) has been more applied in neurodevelopmental disorders... (Review)
Review
A systematic review of randomized controlled trials on efficacy and safety of transcranial direct current stimulation in major neurodevelopmental disorders: ADHD, autism, and dyslexia.
OBJECTIVE
Among the target groups in child and adolescent psychiatry, transcranial direct current stimulation (tDCS) has been more applied in neurodevelopmental disorders specifically, attention-deficit hyperactivity disorder (ADHD), autism spectrum disorder (ASD), and dyslexia. This systematic review aims to provide the latest update on published randomized-controlled trials applying tDCS in these disorders for evaluating its efficacy and safety.
METHODS
Based on a pre-registered protocol (PROSPERO: CRD42022321430) and using the PRISMA approach, a literature search identified 35 randomized controlled trials investigating the effects of tDCS on children and adolescents with ADHD (n = 17), ASD (n = 11), and dyslexia (n = 7).
RESULTS
In ADHD, prefrontal anodal tDCS is reported more effective compared to stimulation of the right inferior frontal gyrus. Similarly in ASD, prefrontal anodal tDCS was found effective for improving behavioral problems. In dyslexia, stimulating temporoparietal regions was the most common and effective protocol. In ASD and dyslexia, all tDCS studies found an improvement in at least one of the outcome variables while 64.7% of studies (11 of 17) in ADHD found a similar effect. About 88% of all tDCS studies with a multi-session design in 3 disorders (16 of 18) reported a significant improvement in one or all outcome variables after the intervention. Randomized, double-blind, controlled trials consisted of around 70.5%, 36.3%, and 57.1% of tDCS studies in ADHD, ASD, and dyslexia, respectively. tDCS was found safe with no reported serious side effects in 6587 sessions conducted on 745 children and adolescents across 35 studies.
CONCLUSION
tDCS was found safe and partially effective. For evaluation of clinical utility, larger randomized controlled trials with a double-blind design and follow-up measurements are required. Titration studies that systematically evaluate different stimulation intensities, duration, and electrode placement are lacking.
Topics: Adolescent; Attention Deficit Disorder with Hyperactivity; Autism Spectrum Disorder; Autistic Disorder; Child; Dyslexia; Humans; Prefrontal Cortex; Randomized Controlled Trials as Topic; Transcranial Direct Current Stimulation
PubMed: 35938945
DOI: 10.1002/brb3.2724 -
Frontiers in Neuroscience 2022The visual word N1 (N170w) is an early brain ERP component that has been found to be a neurophysiological marker for print expertise, which is a prelexical requirement...
UNLABELLED
The visual word N1 (N170w) is an early brain ERP component that has been found to be a neurophysiological marker for print expertise, which is a prelexical requirement associated with reading development. To date, no other review has assimilated existing research on reading difficulties and atypical development of processes reflected in the N170w response. Hence, this systematic review synthesized results and evaluated neurophysiological and experimental procedures across different studies about visual print expertise in reading development. Literature databases were examined for relevant studies from 1995 to 2020 investigating the N170w response in individuals with or without reading disorders. To capture the development of the N170w related to reading, results were compared between three different age groups: pre-literate children, school-aged children, and young adults. The majority of available N170w studies ( = 69) investigated adults ( = 31) followed by children (school-aged: = 21; pre-literate: = 4) and adolescents ( = 1) while some studies investigated a combination of these age groups ( = 12). Most studies were conducted with German-speaking populations ( = 17), followed by English ( = 15) and Chinese ( = 14) speaking participants. The N170w was primarily investigated using a combination of words, pseudowords, and symbols ( = 20) and mostly used repetition-detection ( = 16) or lexical-decision tasks ( = 16). Different studies posed huge variability in selecting electrode sites for analysis; however, most focused on P7, P8, and O1 sites of the international 10-20 system. Most of the studies in adults have found a more negative N170w in controls than poor readers, whereas in children, the results have been mixed. In typical readers, N170w ranged from having a bilateral distribution to a left-hemispheric dominance throughout development, whereas in young, poor readers, the response was mainly right-lateralized and then remained in a bilateral distribution. Moreover, the N170w latency has varied according to age group, with adults having an earlier onset yet with shorter latency than school-aged and pre-literate children. This systematic review provides a comprehensive picture of the development of print expertise as indexed by the N170w across age groups and reading abilities and discusses theoretical and methodological differences and challenges in the field, aiming to guide future research.
SYSTEMATIC REVIEW REGISTRATION
https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42021228444.
PubMed: 35844207
DOI: 10.3389/fnins.2022.898800 -
BMC Public Health May 2022This review is focused on workers with developmental dyslexia (DD). In this review DD is considered an expression of neurodiversity, a consequence of a natural variant...
BACKGROUND
This review is focused on workers with developmental dyslexia (DD). In this review DD is considered an expression of neurodiversity, a consequence of a natural variant of the brain. Evidence was synthesized to explore which factors workers with DD consider relevant for their participation in work and whether these factors reflect shifts in the concepts of health and sustainable employability. The factors were classified according to the International Classification of Functioning, Disability and Health (ICF), adapted for occupational health.
METHODS
A systematic review of qualitative studies was performed. Two search strings were used to determine the population and the context of work. The factors were classified using a recently proposed rearrangement of the ICF scheme that places participation in a central position and incorporates preliminary lists of work-related environmental factors and personal factors.
RESULTS
Fifty-one factors were found that appeared in 35% or more of the included studies and that were relevant to work participation according to the workers themselves. These factors were dispersed over all ICF categories. In the category Functions and Structures (11 factors), most of the factors had negative connotations. In the category Activities (9 factors), all the factors cause difficulties, except speaking (which is ambiguous). In the category Participation (4 factors), the formal relationships are important for the degree of participation. Overall, more than half of the factors are environmental (18) or personal (9) and they both hinder and facilitate work participation.
CONCLUSIONS
The results of this review give an indication for the importance of the biopsychosocial model as a relevant approach for people with a disability in the world of work. This review also adds data for the usefulness of the proposals for the reconsideration of the ICF scheme. The data has not (yet) returned any visible trends revealing that the concept of neurodiversity is common in organizations.
Topics: Activities of Daily Living; Adult; Disability Evaluation; Disabled Persons; Dyslexia; Humans; Qualitative Research
PubMed: 35642026
DOI: 10.1186/s12889-022-13436-x -
Brain Sciences Apr 2022The current study was conducted to examine the percentages of cognitive skills deficits among Chinese children with developmental dyslexia. Via a systematic review, we... (Review)
Review
The current study was conducted to examine the percentages of cognitive skills deficits among Chinese children with developmental dyslexia. Via a systematic review, we collated twenty-two available studies on the proportion of cognitive skills deficits, including phonological awareness, rapid automatized naming, morphological awareness, orthographic knowledge, short-term memory and working memory, and visual and motor skills deficits, among Chinese children with developmental dyslexia. The results of a meta-analysis showed that the rapid automatized naming deficits are the core deficit of developmental dyslexia among Chinese children, with a pooled percentage of 44%. This is followed by orthographic knowledge deficits (43%), phonological awareness deficits (41%), morphological awareness deficits (40%), visual and motor skills deficits (33%), and short-term memory and working memory deficits (25%). At the same time, we compared the proportions of different locations, ages, standards and control groups.
PubMed: 35624935
DOI: 10.3390/brainsci12050548 -
Brain Sciences Feb 2022Developmental dyslexia (DD) is a specific learning disorder concerning reading acquisition that may has a lifelong negative impact on individuals. A reliable estimate of... (Review)
Review
BACKGROUND
Developmental dyslexia (DD) is a specific learning disorder concerning reading acquisition that may has a lifelong negative impact on individuals. A reliable estimate of the prevalence of DD serves as the basis for diagnosis, intervention, and evidence-based health resource allocation and policy-making. Hence, the present meta-analysis aims to generate a reliable prevalence estimate of DD worldwide in primary school children and explore the potential variables related to that prevalence.
METHODS
Studies from the 1950s to June 2021 were collated using a combination of search terms related to DD and prevalence. Study quality was assessed using the STROBE guidelines according to the study design, with study heterogeneity assessed using the statistic, and random-effects meta-analyses were conducted. Variations in the prevalence of DD in different subgroups were assessed via subgroup meta-analysis and meta-regression.
RESULTS
The pooled prevalence of DD was 7.10% (95% CI: 6.27-7.97%). The prevalence in boys was significantly higher than that in girls (boys: 9.22%, 95%CI, 8.07-10.44%; girls: 4.66%, 95% CI, 3.84-5.54%; < 0.001), but no significant difference was found in the prevalence across different writing systems (alphabetic scripts: 7.26%, 95%CI, 5.94-8.71%; logographic scripts: 6.97%, 95%CI, 5.86-8.16%; > 0.05) or across different orthographic depths (shallow: 7.13%, 95% CI, 5.23-9.30%; deep: 7.55%, 95% CI, 4.66-11.04%; > 0.05). It is worth noting that most articles had small sample sizes with diverse operational definitions, making comparisons challenging.
CONCLUSIONS
This study provides an estimation of worldwide DD prevalence in primary school children. The prevalence was higher in boys than in girls but was not significantly different across different writing systems.
PubMed: 35204003
DOI: 10.3390/brainsci12020240 -
Brain Sciences Feb 2022Mathematical performance implies a series of numerical and mathematical skills (both innate and derived from formal training) as well as certain general cognitive... (Review)
Review
UNLABELLED
Mathematical performance implies a series of numerical and mathematical skills (both innate and derived from formal training) as well as certain general cognitive abilities that, if inadequate, can have a cascading effect on mathematics learning. These latter skills were the focus of the present systematic review.
METHOD
The reviewing process was conducted according to the PRISMA statement. We included 46 studies comparing school-aged children's performance with and without math difficulties in the following cognitive domains: processing speed, phonological awareness, short- and long-term memory, executive functions, and attention.
RESULTS
The results showed that some general cognitive domains were compromised in children with mathematical difficulties (i.e., executive functions, attention, and processing speed).
CONCLUSIONS
These cognitive functions should be evaluated during the diagnostic process in order to better understand the child's profile and propose individually tailored interventions. However, further studies should investigate the role of skills that have been poorly investigated to date (e.g., long-term memory and phonological awareness).
PubMed: 35204002
DOI: 10.3390/brainsci12020239 -
Neurological Sciences : Official... Apr 2022Hemianopia is a complete or partial blindness in the visual fields of both eyes, commonly caused by cerebral infarction. It has been hypothesized that systematic... (Review)
Review
BACKGROUND
Hemianopia is a complete or partial blindness in the visual fields of both eyes, commonly caused by cerebral infarction. It has been hypothesized that systematic audio-visual (AV) stimulation of the blind hemifield can improve accuracy and search times, probably due to the stimulation of bimodal representations in the superior colliculus (SC), an important multisensory structure involved in both the initiation and execution of saccades.
METHODS
A narrative synthesis of the findings is presented to highlight how AV rehabilitation impacts on patients with hemianopia including visual oculomotor function, functional ability in activities of daily living, hemianopic dyslexia, visual scanning and searching tasks, maintaining of functional ability post training and the effect on brain multisensory integration by using neuroimaging.
RESULTS
Sixteen studies were included (fourteen articles (188 participants) and two literature reviews). Results were grouped into AV training of hemianopia in adults and in children and then further grouped according to the AV task type: tasks measuring the training effects by comparing visual stimulation training to audio-visual training, localization abilities in homonymous hemianopia (HH) and AV integration in patients with HH.
CONCLUSION
Systematic AV training may improve the processing of visual information by recruiting subcortical pathways, and because most of the patients with visual cortex damage have an intact SC, it might be useful to use the bimodal AV training to activate retinotectal functions. Nevertheless, the underlying mechanisms supporting the reported positive effects are not currently understood. Systematic functional and/or structural imaging studies may help in understanding the underlying mechanism and inform the design of optimal training paradigms.
Topics: Acoustic Stimulation; Activities of Daily Living; Adult; Child; Hemianopsia; Humans; Photic Stimulation; Stroke; Survivors; Visual Fields
PubMed: 35149925
DOI: 10.1007/s10072-022-05926-y