Speech perception in the Specific Learning Disorder with and without Persistent Speech Sound Disorder. / Percepção de fala no transtorno específico da aprendizagem com e sem transtorno persistente dos sons da fala.

PURPOSE: Investigate if speech perception skills can differentiate school children with Specific Reading Disorders (SRD) with and without Persistent Speech Sound Disorders (PSSD). METHODS: 80 children, regularly enrolled in the 2nd (N=1), 3rd (N=28), 4th (N=29), 5th (N=15) and 6th (N=7) grades participated in the study. Control Group (CG) (N=48): no complaints, no speech alteration; and Resarch Group (RG) (N=32) - with SRD, RGI (N=15) without PSSD and RGII (N=17) with PSSD. Two tests evaluated auditory input reception: Simplified evaluation of auditory processing; and Perception task of nonwords, with Portuguese language structure (DNPLS). Data was analyzed by: Likelihood Ratio Test, Kruskal-Wallis test, Dunn test with Bonferroni correction, Mann-Whitney test, Spearman correlation, and construction of a ROC curve to obtain a threshold value for the correct answers in the perception of non-words test. RESULTS: Control and RGI showed higher correct answer scores than RGII. There was no difference between the correct answer distributions of the Control and RGI, and RGI and RGII in the test of DNPLS and the number of correct answers in the CG was higher than in the RGII. CONCLUSION: The ability to discriminate non-words enabled the differentiated between school-aged children with SRD associated with PSSD and typical children, thus characterizing this group for presenting a number of correct answers lower than 30.5, considering the task proposed to discriminate non-words. These results suggest that the presence of PSSD worsens the performance in speech perception of the schoolchildren with SRD.

OBJETIVO: Investigar se a habilidade de percepção de fala pode diferenciar escolares com Transtorno específico de aprendizagem (TAp) com e sem Transtorno Persistente dos Sons da Fala (TPSF). MÉTODO: Participaram da pesquisa 80 crianças, regularmente matriculadas no 2º (N=1), 3º (N=28), 4º (N=29), 5º (N=15), e 6º (N=7) anos, assim reunidos: Grupo Controle (N= 48) - sem queixas, sem alteração de fala; e Grupos Pesquisa (N = 32) - com TAp, sendo GPI (N = 15) sem TPSF e, GPII (N = 17), com TPSF. Duas provas avaliaram input auditivo: Avaliação simplificada do processamento auditivo; e Tarefa de percepção de pseudopalavras com estrutura da língua portuguesa - TDP. Os dados foram analisados pelos testes: Razão de Verossimilhanças, Kruskal-Wallis, Dunn com correção de Bonferroni, Mann-Whitney, correlação de Spearman, além da construção de uma curva ROC para obter um valor de corte para o número de acertos na prova de percepção de não palavras. RESULTADOS: Controle e GPI mostraram maiores escores de acerto que GPII. Não houve diferença entre as distribuições de acertos do Controle e GPI e do GPI e GPII na TDP e o número de acertos do GC foi maior que o do GPII. CONCLUSÃO: A habilidade de discriminação de pseudopalavras diferenciou os escolares com TAp e TPSF das crianças sem TPSF, caracterizando, assim esse grupo por apresentar número de acertos menor que 30,5, considerada a tarefa proposta para discriminar pseudopalavras. Esses resultados sugerem que a presença do TPSF piorou o desempenho em percepção de fala dos escolares com TAp.

Improving cognitive function in Chinese children with ADHD and/or RD through computerized working memory training.

BACKGROUND: Prior research has found that children with attention-deficit hyperactivity disorder (ADHD) and reading difficulties (RD) are at an elevated risk of developing further cognitive deficits and developmental challenges [1]. ADHD and RD are characterized by a deficit in working memory, which negatively affects learning and behavior. The main aims of this study were to design a working memory training app and examine its effectiveness through a 5-week training program in Chinese children with ADHD and/or RD. METHODS: There were three experimental groups, with 26 participants in the ADHD group, 38 participants in the RD group, and 24 participants in the ADHD + RD group. The typically developing (TD) control group had 32 participants. All participants completed the pretest and posttest assessments on executive function and reading performance. RESULTS: The findings indicate that the experimental groups improved performance in verbal and visual-spatial working memory as well as Chinese word reading. There was an overall reduction in functional impairment following the training, in contrast to the TD group. CONCLUSION: This study showed that working memory can be improved through computerized training in children with ADHD and/or RD. The implications of future research in working memory are discussed. TRIAL REGISTRATION: Clinical Trials Identifier: NCT06567444 (retrospectively registered) on 20 August 2024.

Imaging genetics of language network functional connectivity reveals links with language-related abilities, dyslexia and handedness.

Language is supported by a distributed network of brain regions with a particular contribution from the left hemisphere. A multi-level understanding of this network requires studying its genetic architecture. We used resting-state imaging data from 29,681 participants (UK Biobank) to measure connectivity between 18 left-hemisphere regions involved in multimodal sentence-level processing, as well as their right-hemisphere homotopes, and interhemispheric connections. Multivariate genome-wide association analysis of this total network, based on genetic variants with population frequencies  >1%, identified 14 genomic loci, of which three were also associated with asymmetry of intrahemispheric connectivity. Polygenic dispositions to lower language-related abilities, dyslexia and left-handedness were associated with generally reduced leftward asymmetry of functional connectivity. Exome-wide association analysis based on rare, protein-altering variants (frequencies <1%) suggested 7 additional genes. These findings shed new light on genetic contributions to language network organization and related behavioural traits.

Does the procedural deficit hypothesis of dyslexia account for the lack of automatization and the comorbidity among developmental disorders?

We critically examine the procedural deficit hypothesis (PDH) that proposes that a deficit in procedural (as opposed to declarative) learning underlies dyslexia and other developmental disorders. We first note that the existence of dissociated learning disorders (and multiple forms for each disorder) appears incompatible with a general deficit account. Moreover, the PDH formulation appears generally underspecified in terms of predictions to be tested. A particular focus is on the conceptualization of automatization. However, there are alternative views of automaticity, and comparing these different views helps frame the body of findings on the PDH. The insufficient PDH specification led to tasks touching on different skills and selecting target groups based on general diagnostic categories. Accordingly, several recent reviews and meta-analyses reported mixed patterns of findings and reached contradictory conclusions on the PDH. We propose avenues for future research to effectively examine the role of PDH in learning and other developmental disorders.

Advancing Dyslexia Assessment in Children through Computerized Testing.

The acquisition of reading skills is an intricate process that demands the cultivation of various domain-general and domain-specific abilities. Consequently, it is unsurprising that many children grapple with maintaining proficiency at the grade level, particularly when confronted with challenges spanning multiple abilities across both domains, as observed in individuals with reading difficulties. Strikingly, despite reading difficulties being among the most prevalent neurodevelopmental disorders affecting school-aged children, the majority of available diagnostic tools lack a comprehensive framework for assessing the full spectrum of cognitive skills linked to dyslexia, with minimal computerized options. Notably, there are currently limited tools with these features available for Spanish-speaking children. The aim of this study was to delineate the protocol for diagnosing Spanish-speaking children with reading difficulties using the Sicole-R multimedia battery. This tool for elementary grades focuses on evaluating cognitive skills that are associated with dyslexia as prescribed by the scientific literature. Specifically, it concentrates on assessing a range of cognitive abilities that studies have demonstrated to be linked to dyslexia. This focus is based on the observation that individuals with dyslexia typically exhibit deficits in several of the cognitive areas evaluated by this digital tool. The robust internal consistency and multidimensional internal structure of the battery were demonstrated. This multimedia battery has proven to be a fitting tool for diagnosing children with reading difficulties in primary education, offering a comprehensive cognitive profile that is valuable not only for diagnostic purposes but also for tailoring individualized instructional plans.

Causal relationships between dyslexia and the risk of eight dementias.

Observational and genetic studies have reported the relationship between dyslexia and Alzheimer's disease (AD). Until now, the causal effect of dyslexia on AD risk has remained unclear. We conducted a two-sample univariable Mendelian randomization (MR) analysis to determine the causal association between dyslexia and the risk of AD, vascular dementia (VD), Lewy body dementia (LBD), and frontotemporal dementia (FTD) and its four subtypes. First, we selected 42 dyslexia genetic variants from a large-scale genome-wide association studies (GWAS) dataset and extracted their corresponding GWAS summary statistics from AD, VD, LBD, and FTD. Second, we selected four MR methods, including inverse-variance weighted (IVW), weighted median, MR-Egger, and MR-PRESSO. Heterogeneity, horizontal pleiotropy, and leave-one-out sensitivity analysis were then used to evaluate the reliability of all causal estimates. We also conducted multivariable MR (MVMR) and mediation analysis to assess the potential mediating role of cognitive performance (CP) or educational achievement (EA) on the causal association between dyslexia and AD. Two MVMR methods, including MV IVW and MV-Egger, and two-step MR were used to perform the analysis. Using IVW, we found a significant causal association between increased dyslexia and increased risk of AD (OR = 1.15, 95% CI: 1.04-1.28, P = 0.006), but not VD, LBD, FTD, or its four subtypes. MR-PRESSO further supported the statistically significant association between dyslexia and AD (OR = 1.15, 95% CI: 1.05-1.27, P = 0.006). All sensitivity analyses confirmed the reliability of causal estimates. Using MV IVW and mediation analysis, we found no causal relationship between dyslexia and AD after adjusting for CP but not EA, CP mediated the total effect of dyslexia on AD with a proportion of 46.32%. We provide genetic evidence to support a causal effect of increased dyslexia on increased risk of AD, which was largely mediated by CP. Reading activity may be a potential intervention strategy for AD by improving cognitive function.

Dyslexia in the 21st century: revisiting the consensus definition.

Two decades after the International Dyslexia Association (IDA) adopted the 2002 consensus definition of dyslexia, this special issue of the Annals of Dyslexia revisits that definition in light of advances in scientific understanding and evolving needs. Through contributions from leading researchers and interdisciplinary teams, the issue examines the strengths and limitations of the definition as it has been applied in research, policy, and practice. Key themes emerged, which included reconsidering the need to include the neurobiological basis of dyslexia in the definition, the intersection of literacy challenges and mental health, and the role of context in shaping how dyslexia is defined. Contributors to this special issue also reflected on how the definition serves different audiences, including educators, policymakers, and families. As the IDA embarks on a thoughtful reassessment of the 2002 definition, this collection of articles offers insights to guide the path forward, ensuring the definition remains a robust tool for research, identification, intervention, and advocacy in the coming years.

Reading skill profiles of dysfluent readers in grades 2 and 3.

Text reading fluency (TRF) is a common reading intervention target in second and third grade. TRF requires the integration of several skills that result in several pathways to dysfluent reading. However, when applying the drill-down approach to intervention targeting, practitioners are guided to consider students' rate and accuracy when reading connected text after ruling out decoding difficulties. A question remains whether students' reading rate and accuracy alone is sensitive to differences in the underlying skills that promote TRF. We used latent profile analysis to investigate whether different profiles of component reading skills could be identified among second- (n = 127) and third-grade (n = 170) students who were referred for an intervention targeting TRF. Most students were identified as white (56%) and students were predominately English speakers (87%). At the beginning of the intervention, we measured participants' skills in listening comprehension, reading comprehension, reading vocabulary, word reading efficiency, and decoding efficiency. Four profiles emerged in both grades with similar patterns in terms of the component skills influencing TRF. Students in two of the profiles demonstrated relative strengths in word reading or reading comprehension with their other skills near the sample average. A third profile approximated the sample average across all component skills whereas the fourth profile was below the sample average in all measured skills. However, some of the empirically derived profiles did not differ in terms of students' average reading rate. For example, the average words read correct per minute did not significantly differ between students with relative strengths in comprehension and students with relative strengths with word reading. Our results suggest that differences in students' text reading rate and accuracy may not always capture potentially relevant differences in the skills that influence TRF.

Pulsed lighting for adults with Dyslexia: very limited impact, confined to individuals with severe reading deficits.

The goal of this study is to evaluate the impact of pulsed lighting on the reading performance of young adults with dyslexia. A total of 42 participants were recruited, including individuals diagnosed with developmental dyslexia and adults without reported reading difficulties. The severity of each participant's reading deficit was assessed on a continuous scale using a reading impairment score, derived from four reading tests: an isolated-word reading test, a pseudoword reading test, and two reading fluency tests. The impairment score ranged from 0 (no impairment) to 4 (severe impairment across all tests). To examine the potential effect of pulsed lighting, we measured (1) sentence reading speed, expressed as a reading accessibility index (ACC), and (2) text comprehension, expressed as a comprehension score. These measures were taken under three lighting conditions: standard lighting, pulsed lighting, and a combination of the two. Linear mixed-effects models were applied to assess the effects of lighting on ACC and comprehension, controlling for the reading impairment score. We found no effect of lighting conditions on either ACC or comprehension, except in the most impaired readers, who showed a small but significant increase of 7% in ACC. However, even with pulsed lighting, impaired readers did not reach the performance level of skilled adult readers. In conclusion, the study did not demonstrate a clear positive impact of pulsed lighting on the reading skills of adults with dyslexia.

Developmental dyslexia in children with perinatal exposure to hypoxia: A systematic review.

BACKGROUND: Research on a health-related event at the stage of labour and the occurrence of adverse outcomes at the school age has provided inconclusive results. Thus far, no systematic reviews have been conducted. Thus, the objective of this study is to investigate the association between hypoxia during pregnancy or delivery and the subsequent occurrence of a developmental dyslexia in school-age children. METHODS: We used a standard search strategy of electronic databases (PubMed, PsycINFO, Web of Science, EMBASE, and Cochrane Library) and handsearching. We included observational studies (cohort studies, case-control studies) that consider as an exposure the presence of hypoxia during pregnancy or delivery, and as an outcome, developmental dyslexia in school-age children. Two reviewers independently conducted the search and determined eligibility, which was not restricted by language or year of publication. RESULTS: The search took place until 1 April 2023. Of the 1,336 abstracts screened, 6 were assessed for eligibility. Of the six eligible studies, no studies met the pre-specified eligibly criteria. CONCLUSIONS: We were unable to assess the association between hypoxia and developmental dyslexia, as no eligible studies were found. Thus, the association between hypoxia during pregnancy or delivery and dyslexia in school-age children remains unknown.

Nurses with dyslexia: overcoming challenges and thriving in the profession.

Dyslexia is a specific learning difficulty impacting reading, writing and spelling. Practising nursing requires a unique set of skills that encompass effective communication, critical thinking, and organisational skills. This article focuses on the experiences of nurses with dyslexia, shedding light on the distinct challenges they encounter and the resilient strategies they employ to navigate their roles and excel in the health profession.

Perceptual anchoring: Children with dyslexia benefit less than controls from contextual repetitions in speech processing.

OBJECTIVES: Individuals with dyslexia perceive and utilize statistical features in the auditory input deficiently. The present study investigates whether affected children also benefit less from repeating context tones as perceptual anchors for subsequent speech processing. METHODS: In an event-related potential study, eleven-year-old children with dyslexia (n = 21) and without dyslexia (n = 20) heard syllable pairs, with the first syllable either receiving a constant pitch (anchor) or variable pitch (no-anchor), while second syllables were identical across conditions. RESULTS: Children with and without dyslexia showed smaller auditory P2 responses to constant-pitch versus variable-pitch first syllables, while only control children additionally showed smaller N1 and faster P1 responses. This suggests less automatic processing of anchor repetitions in dyslexia. For the second syllables, both groups showed faster P2 responses following anchor than no-anchor first syllables, but only controls additionally showed smaller P2 responses. CONCLUSIONS: Children with and without dyslexia show differences in anchor effects. While both groups seem to allocate less attention to speech stimuli after contextual repetitions, children with dyslexia display less facilitation in speech processing from acoustic anchors. SIGNIFICANCE: Altered anchoring in the linguistic domain may contribute to the difficulties of individuals with dyslexia in establishing long-term representations of speech.

Simultaneous simulations of pure, surface and phonological acquired dyslexia within a full computational model of the primary systems hypothesis.

According to the primary systems hypothesis, reading requires interactions of visual-orthographic, phonological and semantic systems. Damage to each primary system generates very different types of acquired dyslexia. Variants of the connectionist 'triangle' models of reading have been developed to investigate individual acquired dyslexia. However, only a few studies have investigated multiple acquired alexia within one framework. Importantly, there are no studies that simultaneously simulate both central dyslexia (e.g. surface and phonological dyslexia) and peripheral dyslexia (e.g. pure alexia). That is largely due to the lack of a visual component in the traditional reading models. To verify the predictions made by the primary systems hypothesis, we developed a connectionist 'deep' multi-layer triangle model of reading including visual, orthographic, phonological and semantic processing layers. We investigated whether damage to the model could produce the general behavioural patterns of impaired performance observed in patients with the corresponding reading deficits. Crucially, damage to the visual-orthographic, phonological or semantic components of the model resulted in the expected reading impairments associated with pure alexia, phonological dyslexia and surface dyslexia, respectively. The simulation results demonstrated for the first time that neurologically-impaired reading including both central and peripheral dyslexia could be addressed within a single triangle model of reading. The findings are consistent with the predictions made by the primary systems hypothesis.

The perceptual span in dyslexic reading and visual search.

Many studies have attempted to identify the root cause of dyslexia. Different theories of dyslexia have proposed either a phonological, attentional, or visual deficit. While research has used eye-tracking to study dyslexia, only two previous studies have used the moving-window paradigm to explore the perceptual span in dyslexic reading, and none have done so in visual search. The present study analysed the perceptual span using both reading and visual search tasks to identify language-independent attentional impairments in dyslexics. We found equivocal evidence that the perceptual span was impaired in dyslexic reading and no evidence of impairment in visual search. However, dyslexic participants did show deficits in the visual search task, with lower search accuracy and shorter saccades compared with controls. These results lend support for a visual, rather than attentional or phonological, account of dyslexia.

Proprioceptive intervention improves reading performance in developmental dyslexia: An eye-tracking study.

Developmental dyslexia is characterized by difficulties in learning to read, affecting cognition and causing failure at school. Interventions for children with developmental dyslexia have focused on improving linguistic capabilities (phonics, orthographic and morphological instructions), but developmental dyslexia is accompanied by a wide variety of sensorimotor impairments. The goal of this study was to examine the effects of a proprioceptive intervention on reading performance and eye movement in children with developmental dyslexia. Nineteen children diagnosed with developmental dyslexia were randomly assigned to a regular Speech Therapy (ST) or to a Proprioceptive and Speech Intervention (PSI), in which they received both the usual speech therapy and a proprioceptive intervention aimed to correct their sensorimotor impairments (prism glasses, oral neurostimulation, insoles and breathing instructions). Silent reading performance and eye movements were measured pre- and post-intervention (after nine months). In the PSI group, reading performance improved and eye movements were smoother and faster, reaching values similar to those of children with typical reading performance. The recognition of written words also improved, indicating better lexical access. These results show that PSI might constitute a valuable tool for reading improvement children with developmental dyslexia.

Presentation matters: Surface text features and text quality in written narratives of Dutch high school students with and without dyslexia.

Presentation features such as spelling, punctuation and handwriting can influence the evaluation of general text quality. High school students with dyslexia might therefore be at a disadvantage, as at least their spelling performance is typically poor(er). Furthermore, these students might show less sophisticated linguistic features of texts, such as word length and sentence complexity, that might also be related to text quality. We compared narratives written by Dutch high school students (mean age 13.7 years) with (n = 28) and without (n = 29) dyslexia. Students with dyslexia's texts contained more spelling errors and poorer handwriting quality, but not more punctuation errors. Teacher-rated general text quality was lower for the texts of students with dyslexia in uncorrected versions. When spelling and punctuation errors were corrected, no teacher-rated text quality differences emerged. No differences in linguistic text features were found. Furthermore, spelling, punctuation and, to a lesser extent, number of words per sentence clause were related to ratings of text quality across participants. These results confirm the influence of presentation features on text quality rating. They encourage teachers to be aware of this effect and emphasize the importance of spelling and writing support and interventions for students with dyslexia throughout education.

Exploring mothers' metaphorical sensemaking of dyslexia.

Through a reflexive thematic analysis of a large online support group for dyslexia and a sensemaking lens, this study investigated how mothers made sense of their child's dyslexia through metaphors. Mothers used metaphors to characterise their feelings surrounding dyslexia, their school-based interactions and their identity as advocates. The language mothers use offers a generative, textured way to understand the lived experiences of supporting a child with learning differences. Whilst mothers articulated much frustration and anger, they also voiced encouragement, advice-giving, empathy and hope, illustrating how their sense of agency was both threatened and empowered by the experience of having a child with dyslexia. There is much mothers must process, understand and navigate surrounding their child's dyslexia and the findings underscore the need for early school-based screening, support and intervention.

Increasing inter-word spacing reduces migration errors and improves reading comprehension in students with dyslexia.

We report a small study in which we explored the effects of manipulating narrative text on levels of comprehension for students with and without dyslexia. Using two pieces of standardised narrative text deemed to be of similar difficulty and length, we manipulated the texts such that we could present two texts to each participant, one in each condition. The first condition was text using standard inter-word spacing; the second condition used increased inter-word spacing. Scores on standardised comprehension questions were significantly improved for participants with dyslexia. Additionally, given that there is evidence of delayed visual attention disengagement in individuals with specific forms of dyslexia, we hypothesised that the phenomena of migration of letters and words for some readers might be mitigated by increasing inter-word spacing. We did indeed find that incidence of migration was significantly reduced in this condition for all participants.

The Big Five Personality Traits in Dyslexic Adults: An Exploratory Study.

BACKGROUND: Dyslexia is a neurodevelopmental disorder that causes a pattern of learning difficulties that can be characterized by deficits in word reading accuracy, speed or fluency, and reading comprehension. Due to all this damage, emotional difficulties have been described in the literature mainly for childhood and adolescence. Within this emotional component, personality can be included. In Brazil, at the time of carrying out this research, no research had been found that investigated the personality of dyslexic adults. Thus, the present study aimed to investigate the personality of Brazilian adults with dyslexia. METHODS: A semi-structured interview was administered and the Factorial Personality Battery, based on the Big Five personality traits. The sample was composed of two groups: one with dyslexia and another control. The first was formed by nine participants, aged between 18 and 47 (M = 31.7; standard deviation (SD) = 11.8), six of whom were women. The control group was formed by 60 participants, aged between 18 and 45 years (M = 26.4; SD = 8.8), 38 of whom were women. RESULTS: The data did not show significant differences between the groups in most of the analyzed factors and subfactors. Increased rates of "passivity/lack of energy" and lowered rates of "openness to new ideas" were identified in the group with dyslexia. CONCLUSION: These results could be useful for describing personality profiles in dyslexic adults, with these descriptions possibly providing clinical support for diagnoses and intervention procedures.

Correction to effects of a visual perception-based occupational therapy programme on reading and motor skills in children with developmental dyslexia: Single blind randomised crossover study design.

This study aimed to examine the effects of a visual praxis-based occupational therapy (VPOT) programme on reading and motor skills for children with developmental dyslexia (DD). Forty-two children were included in the study. Additionally, before VPOT, the Reading-Aloud and Reading-Comprehension Test 2 (ORSRC-2) and the Bruininks-Oseretsky Motor-Proficiency-Test-2-Brief Form (BOT2-BF) were applied to the participants. According to the study design, VPOT was applied to two sessions per week for 8 weeks to group A. During this period, group B was accepted as the control group. At the end of these 8 weeks, evaluation tests were applied to both groups. Then, group A was defined as the control group and Group B as the intervention group, and VPOT was applied to Group B. At the end of another 8 weeks, evaluation tests were applied to both groups for the third time. When the final ORSRC-2 results were examined, VPOT was found to be an effective programme for improving reading skills. Additionally, when the final BOT2-BF results were examined, VPOT was determined to be effective in improving motor skills (p < 0.05). We believe that it is important to carry out comprehensive studies such as the VPOT programme to solve problems in the physical and learning activities of children with DD.