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Cognitive Neuropsychology May 2021The imaging genetics of specific reading disabilities (SRD) is an emerging field that aims to characterize the disabilities' neurobiological causes, including atypical... (Meta-Analysis)
Meta-Analysis
The imaging genetics of specific reading disabilities (SRD) is an emerging field that aims to characterize the disabilities' neurobiological causes, including atypical brain structure and function and distinct genetic architecture. The present review aimed to summarize current imaging genetics studies of SRD, characterize the effect sizes of reported results by calculating Cohen's complete a Fisher's Combined Probability Test for genes featured in multiple studies, and determine areas for future research. Results demonstrate associations between SRD risk genes and reading network brain phenotypes. The Fisher's test revealed promising results for the genes and Future research should focus on exploratory approaches to identify previously undiscovered genes. Using comprehensive neuroimaging (e.g., functional and effective connectivity) and genetic (e.g., sequencing and epigenetic) techniques, and using larger samples, diverse stages of development, and longitudinal investigations, would help researchers understand the neurobiological correlates of SRD to improve early identification.
Topics: Brain; Dyslexia; Humans; Microtubule-Associated Proteins; Nerve Tissue Proteins; Neuroimaging; Receptors, Immunologic
PubMed: 34529546
DOI: 10.1080/02643294.2021.1969900 -
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 -
Frontiers in Psychology 2021The use of electronic interventions to improve reading is becoming a common resource. This systematic review aims to describe the main characteristics of randomized...
The use of electronic interventions to improve reading is becoming a common resource. This systematic review aims to describe the main characteristics of randomized controlled trials or quasi-experimental studies that have used these tools to improve first-language reading, in order to highlight the features of the most reliable studies and guide future research. The whole procedure followed the PRISMA guidelines, and the protocol was registered before starting the process (doi: 10.17605/OSF.IO/CKM4N). Searches in Scopus, PubMed, Web of Science and an institutional reference aggregator (Unika) yielded 6,230 candidate articles. After duplicate removal, screening, and compliance of eligibility criteria, 55 studies were finally included. They were research studies on improving first-language reading, both in children and adults, and including a control group. Thirty-three different electronic tools were employed, most of them in English, and studies were very diverse in sample size, length of intervention, and control tasks. Risk of bias was analyzed with the PEDro scale, and all studies had a medium or low risk. However, risk of bias due to conflicts of interest could not be evaluated in most studies, since they did not include a statement on this issue. Future research on this topic should include randomized intervention and control groups, with sample sizes over 65 per group, interventions longer than 15 h, and a proper disclosure of possible conflicts of interest. : The whole procedure followed the PRISMA guidelines, and the protocol was registered before starting the process in the Open Science Framework (doi: 10.17605/OSF.IO/CKM4N).
PubMed: 34603117
DOI: 10.3389/fpsyg.2021.652948 -
Annals of Dyslexia Jul 2023Dyslexia is one of the most studied learning disorders. Despite this, its biological basis and main causes are still not fully understood. Electroencephalography (EEG)...
Dyslexia is one of the most studied learning disorders. Despite this, its biological basis and main causes are still not fully understood. Electroencephalography (EEG) could be a powerful tool in identifying the underlying mechanisms, but knowledge of the EEG correlates of developmental dyslexia (DD) remains elusive. We aimed to systematically review the evidence on EEG correlates of DD and establish their quality. In July 2021, we carried out an online search of the PubMed and Scopus databases to identify published articles on EEG correlates in children with dyslexia aged 6 to 12 years without comorbidities. We follow the PRISMA guidelines and assess the quality using the Appraisal Tool questionnaire. Our final analysis included 49 studies (14% high quality, 63% medium, 20% low, and 2% very low). Studies differed greatly in methodology, making a summary of their results challenging. However, some points came to light. Even at rest, children with dyslexia and children in the control group exhibited differences in several EEG measures, particularly in theta and alpha frequencies; these frequencies appear to be associated with learning performance. During reading-related tasks, the differences between dyslexic and control children seem more localized in the left temporoparietal sites. The EEG activity of children with dyslexia and children in the control group differed in many aspects, both at rest and during reading-related tasks. Our data are compatible with neuroimaging studies in the same diagnostic group and expand the literature by offering new insights into functional significance.
Topics: Child; Humans; Dyslexia; Reading; Electroencephalography; Learning Disabilities
PubMed: 36417146
DOI: 10.1007/s11881-022-00273-1 -
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 -
International Journal of Environmental... Jan 2023Children with dyslexia are at elevated risk of internalising and externalising mental health concerns. Our aim was to scope the extent and nature of the literature...
Children with dyslexia are at elevated risk of internalising and externalising mental health concerns. Our aim was to scope the extent and nature of the literature investigating factors which may influence this association. We systematically searched the peer-reviewed and grey literature with no restrictions on the date. We included both qualitative and quantitative studies. Inclusion criteria included: (1) a focus on childhood (≤18 years) reading/learning difficulties; (2) internalising and/or externalising symptoms; and (3) a potentially modifiable third factor (e.g., self-esteem). Ninety-eight studies met the inclusion criteria. We organised the studies according to individual, family, and community-level third factors. Whilst a range of third factors were identified, relatively few researchers tested associations between the third factor and mental health in the context of dyslexia. Furthermore, there was a focus on primary rather than secondary school experience and a reliance, in many cases, on teacher/parent perspectives on children's mental health. Future researchers are encouraged to explore links between socio-emotional skills, coping strategies, school connectedness, and mental health in the context of dyslexia. Research of this nature is important to assist with the identification of children who are more (or less) at risk of mental health concerns and to inform tailored mental health programs for children with dyslexia.
Topics: Child; Humans; Adaptation, Psychological; Cognition; Dyslexia; Emotions; Mental Health
PubMed: 36674408
DOI: 10.3390/ijerph20021653 -
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 -
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 -
Dyslexia (Chichester, England) May 2022Inconsistencies in the operationalisation of dyslexia in assessment practices are concerning. Variations in different countries' education contexts and education-related...
Inconsistencies in the operationalisation of dyslexia in assessment practices are concerning. Variations in different countries' education contexts and education-related legislation could contribute to continuing discrepancies between psychologists' assessment practices. However, an international "snapshot" of these practices is unavailable. An international comparison of psychologists' dyslexia assessment practices could help ascertain whether there are contextual factors that can foster converging practices. Accordingly, this study systematically reviewed the literature to capture how psychologists identify and/or diagnose dyslexia across English-speaking countries. Quantitative and/or qualitative studies, published between 2013 and 2021, that investigated psychologists' self-reported methods for assessing, identifying, and/or diagnosing individuals with dyslexia were included. Eleven studies (published across fourteen papers) met the inclusion criteria. Most included studies sampled school psychologists who work in the USA. Psychologists' dyslexia assessment practices were diverse (including the use of cognitive discrepancy and response-to-intervention methods). The results highlight an international need to develop a consensus operational definition of dyslexia and universal assessment guidelines. Future research might investigate the practices and beliefs of psychologists who work outside of the USA, and to be inclusive of adult populations. Implications for research and training are explored.
Topics: Adult; Dyslexia; Humans
PubMed: 34931397
DOI: 10.1002/dys.1706 -
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