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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 -
Brazilian Journal of Otorhinolaryngology 2022To investigate ocular movements measures of vectoelectro-nystagmography and video-nystagmography in dyslexic children and compare with measures of typical children. (Meta-Analysis)
Meta-Analysis Review
OBJECTIVE
To investigate ocular movements measures of vectoelectro-nystagmography and video-nystagmography in dyslexic children and compare with measures of typical children.
METHODS
A systematic review of observational studies comparing the ocular movements differences between dyslexic and typical children with no publication date or language restriction. The literature survey included the bibliographic databases MEDLINE, ScienceDirect, Scopus, Web of Science, SciELO, Lilacs and CENTRAL. Gray literature databases were also searched, including: OpenGrey.eu, DissOnline.de, The New York Academy of Medicine and WorldCat. The meta-analysis was performed using software RevMan 5.3 (Cochran Collaboration).
RESULTS
A total of 2375 articles were found of which 113 fell within the inclusion criteria. Among these, 52 were duplicates (found in more than one research source), and 45 articles were selected for reading in full. Thirteen (13) articles were included for analysis and discussion. Meta-analysis showed statistical differences between the two groups for the total number of saccades and duration of fixation.
CONCLUSION
The study revealed that children with dyslexia have longer duration of fixation and fewer saccades during ocular movements on vectoelectro-nystagmography and video-nystagmography when compared to children without dyslexia.
Topics: Child; Humans; Fixation, Ocular; Dyslexia; Saccades; Reading; Eye Movements
PubMed: 35094959
DOI: 10.1016/j.bjorl.2021.10.006 -
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 -
Neuroscience and Biobehavioral Reviews Jan 2022Behavioral research supports the efficacy of intervention for reading disability, but the brain mechanisms underlying improvement in reading are not well understood.... (Meta-Analysis)
Meta-Analysis Review
Behavioral research supports the efficacy of intervention for reading disability, but the brain mechanisms underlying improvement in reading are not well understood. Here, we review 39 neuroimaging studies of reading intervention to characterize links between reading improvement and changes in the brain. We report evidence of changes in activation, connectivity, and structure within the reading network, and right hemisphere, frontal and sub-cortical regions. Our meta-analysis of changes in brain activation from pre- to post- reading intervention in eight studies did not yield any significant effects. Methodological heterogeneity among studies may contribute to the lack of significant meta-analytic findings. Based on our qualitative synthesis, we propose that brain changes in response to intervention should be considered in terms of interactions among distributed cognitive, linguistic and sensory systems, rather than via a "normalized" vs. "compensatory" dichotomy. Further empirical research is needed to identify effects of moderating factors such as features of intervention programs, neuroimaging tasks, and individual differences among participants.
Topics: Brain; Brain Mapping; Dyslexia; Humans; Magnetic Resonance Imaging; Neuronal Plasticity
PubMed: 34856223
DOI: 10.1016/j.neubiorev.2021.11.011 -
Human Brain Mapping Feb 2022Noninvasive brain stimulation (NIBS) allows to actively and noninvasively modulate brain function. Aside from inhibiting specific processes, NIBS may also enhance...
Noninvasive brain stimulation (NIBS) allows to actively and noninvasively modulate brain function. Aside from inhibiting specific processes, NIBS may also enhance cognitive functions, which might be used for the prevention and intervention of learning disabilities such as dyslexia. However, despite the growing interest in modulating learning abilities, a comprehensive, up-to-date review synthesizing NIBS studies with dyslexics is missing. Here, we fill this gap and elucidate the potential of NIBS as treatment option in dyslexia. The findings of the 15 included studies suggest that repeated sessions of reading training combined with different NIBS protocols may induce long-lasting improvements of reading performance in child and adult dyslexics, opening promising avenues for future research. In particular, the "classical" reading areas seem to be most successfully modulated through NIBS, and facilitatory protocols can improve various reading-related subprocesses. Moreover, we emphasize the need to further explore the potential to modulate auditory cortex function as a preintervention and intervention approach for affected children, for example, to avoid the development of auditory and phonological difficulties at the core of dyslexia. Finally, we outline how future studies may increase our understanding of the neurobiological basis of NIBS-induced improvements in dyslexia.
Topics: Dyslexia; Humans; Transcranial Direct Current Stimulation; Transcranial Magnetic Stimulation
PubMed: 34716977
DOI: 10.1002/hbm.25700 -
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 -
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 -
Journal of Speech, Language, and... Aug 2021Purpose We report the results of a systematic review and meta-analysis investigating the relationship between perceptual anchoring and dyslexia. Our goal was to assess... (Meta-Analysis)
Meta-Analysis
Purpose We report the results of a systematic review and meta-analysis investigating the relationship between perceptual anchoring and dyslexia. Our goal was to assess the direction and degree of the effect between perceptual anchoring and reading ability in typical and atypical (i.e., dyslexic) readers. Method We performed a literature search of experiments explicitly assessing perceptual anchoring and reading ability using PsycInfo (Ovid, 1860-2020), MEDLINE (Ovid, 1860-2019), EMBASE (Ovid, 1883-2019), and PubMed for all available years up to June (2020). Our eligibility criteria consisted of English language articles, and, at minimum, one experimental group identified as dyslexic-either by reading assessment at the time or by previous diagnosis. We assessed for risk of bias using an adapted version of the Newcastle-Ottawa Scale. Eight studies were included in this review and meta-analysis ( = 422 participants). Results The overall effect was negative, moderate, and statistically significant; = -0.70, 95% confidence interval [-1.10, -0.29]: a negative effect size indicating less perceptual anchoring in dyslexic versus nondyslexic groups. Visual assessment of funnel plot and Egger's test suggest minimal bias but with significant heterogeneity; Q (7) = 17.03, prediction interval [-1.79, 0.40]. Conclusions Of the included studies, we find evidence for a moderate perceptual anchoring deficit in individuals with dyslexia. The primary limitation of the current review is the small number of included studies. The variability of effect sizes appears consistent with the inherent variability within subtypes of dyslexia.
Topics: Dyslexia; Humans; Language; Reading
PubMed: 34289307
DOI: 10.1044/2021_JSLHR-20-00533 -
Effects of transcranial stimulation in developmental neurocognitive disorders: A critical appraisal.Progress in Brain Research 2021Non-invasive brain stimulation (NIBS) has been highlighted as a powerful tool to promote neuroplasticity, and an attractive approach to support cognitive remediation....
Non-invasive brain stimulation (NIBS) has been highlighted as a powerful tool to promote neuroplasticity, and an attractive approach to support cognitive remediation. Here we provide a systematic review of 26 papers using NIBS to ameliorate cognitive dysfunctions in three prevalent neurodevelopmental disorders: Attention-Deficit/Hyperactivity Disorder (ADHD), Developmental Dyslexia and Developmental Dyscalculia. An overview of the state of research shows a predominance of studies using repetitive transcranial magnetic stimulation (rTMS) and transcranial direct current stimulation (tDCS) techniques, and an unequal distribution among clinical conditions. Regarding the utility of NIBS, the results are promising but also ambiguous. Twenty-three papers reported beneficial effects, but many of these effects were found only once or were only partially replicated and some studies even reported detrimental effects. Furthermore, most studies differed in at least one core aspect, the NIBS applied, the questionnaires and cognitive tests conducted, or the age group investigated, and sample sizes were mostly small. Hence, further studies are needed to rigorously examine the potential of NIBS in the remediation of cognitive functions. Finally, we discuss potential caveats and future directions. We reason that if adequately addressing these challenges NIBS can be feasible, with potential benefits in treating neurodevelopmental disorders.
Topics: Attention Deficit Disorder with Hyperactivity; Cognition; Cognitive Dysfunction; Humans; Transcranial Direct Current Stimulation; Transcranial Magnetic Stimulation
PubMed: 34167652
DOI: 10.1016/bs.pbr.2021.01.012 -
Language, Speech, and Hearing Services... Jul 2021Purpose A systematic review was performed to determine the extent to which orthographic facilitation, a strategy to improve word learning, has been demonstrated in the... (Review)
Review
Purpose A systematic review was performed to determine the extent to which orthographic facilitation, a strategy to improve word learning, has been demonstrated in the literature for children and adolescents from clinical categories such as developmental language disorders (DLD), autism spectrum disorders (ASD), Down syndrome, dyslexia, hearing impairment, intellectual disability, and cerebral palsy. Method Five databases were searched for all studies published through December 2019. Eligible studies included participants from a clinical population (DLD, ASD, dyslexia, cerebral palsy, Down syndrome, hearing impairment, etc.) and compared word learning with and without orthography. Selected studies were extracted for pertinent information. In addition, assessment of the methodological rigor was performed for each study. Results The review yielded five studies that targeted word learning with orthographic facilitation for children from various clinical populations including DLD, verbal children with autism, Down syndrome, and dyslexia. All studied populations showed a benefit for word learning in picture naming posttests when words were trained in the presence of orthography. Conclusions For the studied populations, training words in the presence of orthography will improve word learning accuracy and retention. The review highlights the need for more research in this area across other clinical populations. Supplemental Material https://doi.org/10.23641/asha.14632791.
Topics: Adolescent; Autism Spectrum Disorder; Child; Dyslexia; Humans; Language Development Disorders; Verbal Learning
PubMed: 34029128
DOI: 10.1044/2021_LSHSS-20-00123