Working memory deficits in children with specific learning disorders

Is Training Working Memory in Children with Learning Disabilities a Viable Solution? A Systematic Review

Background

Working memory (WM) is one of the most influential cognitive functions in encoding, registering, and retrieving information. It influences the learning process in children. Its role becomes essential, especially in a child with a learning disability (LD). Researchers worldwide are giving much prominence to WM, especially in devising cognitive retraining strategies for better cognitive functioning and academic attainment in these children. This current study aims to explore globally used instruments to measure this construct and review effective WM training models in the cognitive rehabilitation of children with LD. This study used a systematic review, availing the elaborate "Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA)" guidelines.

Summary

The databases of Google Scholar, PubMed, and Web of Science were searched thoroughly, and those studies, which met the inclusion criteria, were considered for this review. Out of 770 studies found with keywords, only six met the inclusion criteria and were selected for a detailed analysis. The outcome of the current review provides trustworthy evidence of poor performance, especially in tasks involving verbal and executive WM in children with all types of learning disabilities (LD) and difficulties. The studies reviewed support the hypothesis that WM can improve with training and significantly improve children's academic attainment.

Key Message

Further this review recommends that research and efforts must go into devising these cognitive training techniques. Children have high cerebral plasticity; hence, using cognitive training (emphasizing WM training and other cognitive functions) with them would enhance their cognitive functioning and capacity, improving their academic performance.

Neurocognitive mechanisms of co-occurring math difficulties in dyslexia: Differences in executive function and visuospatial processing

Children with dyslexia frequently also struggle with math. However, studies of reading disability (RD) rarely assess math skill, and the neurocognitive mechanisms underlying co-occurring reading and math disability (RD+MD) are not clear. The current study aimed to identify behavioral and neurocognitive factors associated with co-occurring MD among 86 children with RD. Within this sample, 43% had co-occurring RD+MD and 22% demonstrated a possible vulnerability in math, while 35% had no math difficulties (RD-Only). We investigated whether RD-Only and RD+MD students differed behaviorally in their phonological awareness, reading skills, or executive functions, as well as in the brain mechanisms underlying word reading and visuospatial working memory using functional magnetic resonance imaging (fMRI). The RD+MD group did not differ from RD-Only on behavioral or brain measures of phonological awareness related to speech or print. However, the RD+MD group demonstrated significantly worse working memory and processing speed performance than the RD-Only group. The RD+MD group also exhibited reduced brain activations for visuospatial working memory relative to RD-Only. Exploratory brain-behavior correlations along a broad spectrum of math ability revealed that stronger math skills were associated with greater activation in bilateral visual cortex. These converging neuro-behavioral findings suggest that poor executive functions in general, including differences in visuospatial working memory, are specifically associated with co-occurring MD in the context of RD. RESEARCH HIGHLIGHTS: Children with reading disabilities (RD) frequently have a co-occurring math disability (MD), but the mechanisms behind this high comorbidity are not well understood. We examined differences in phonological awareness, reading skills, and executive function between children with RD only versus co-occurring RD+MD using behavioral and fMRI measures. Children with RD only versus RD+MD did not differ in their phonological processing, either behaviorally or in the brain. RD+MD was associated with additional behavioral difficulties in working memory, and reduced visual cortex activation during a visuospatial working memory task.

Far Transfer Effects of Trainings on Executive Functions in Neurodevelopmental Disorders: A Systematic Review and Metanalysis

Executive Functions are a set of interrelated, top-down processes essential for adaptive goal-directed behaviour, frequently impaired across different neurodevelopmental disorders with variable degrees of severity. Many executive-function-training studies in children with neurodevelopmental disorders have focused on near effects, investigating post-treatment improvements on directly trained processes, while enhancements of skills not directly trained, defined as far effects, are less considered, albeit these could be extremely relevant for reducing the negative impact of a disorder's core symptomatology. This systematic review and metanalysis aims to investigate the far effect outcomes after EF training in children with different types of neurodevelopmental disorders. 17 studies met the inclusion criteria for the systematic review, while 15 studies were selected in the metanalysis. An overall statistically significant effect size was found in the majority of far effect outcome measures considered in the studies. In particular, trainings on executive functions determine significant far effects on daily life functioning (0.46, 95% CI: [0.05-0.87]) and clinical symptoms (0.33, 95% CI: [0.15-0.51]). Despite a high variability of the results, intensity, frequency and the laboratory/life contexts dimension seem to be the most influential variables in determining far effects. This systematic review and metanalysis highlights the need to measure far effects of executive function training in neurodevelopmental disorders, selecting treatments not only on directly targeted processes, but also according to far impacts on the functional weakness of the disorder.

Let's face it! The role of social anxiety and executive functions in recognizing others' emotions from faces: Evidence from autism and specific learning disorders

Youth with different developmental disorders might experience challenges when dealing with facial emotion recognition (FER). By comparing FER and related emotional and cognitive factors across developmental disorders, researchers can gain a better understanding of challenges and strengths associated with each condition. The aim of the present study was to investigate how social anxiety and executive functioning might underlie FER in youth with and without autism spectrum disorders (ASD) and specific learning disorders (SLD). The study involved 263 children and adolescents between 8 and 16 years old divided into three groups matched for age, sex, and IQ: 60 (52 M) with ASD without intellectual disability, 63 (44 M) with SLD, and 140 (105 M) non-diagnosed. Participants completed an FER test, three executive functions' tasks (inhibition, updating, and set-shifting), and parents filled in a questionnaire reporting their children's social anxiety. Our results suggest that better FER was consistent with higher social anxiety and better updating skills in ASD, while with lower social anxiety in SLD. Clinical practice should focus on coping strategies in autistic youth who could feel anxiety when facing social cues, and on self-efficacy and social worries in SLD. Executive functioning should also be addressed to support social learning in autism.

Sensory temporal sampling in time: an integrated model of the TSF and neural noise hypothesis as an etiological pathway for dyslexia

Much progress has been made in research on the causal mechanisms of developmental dyslexia. In recent years, the "temporal sampling" account of dyslexia has evolved considerably, with contributions from neurogenetics and novel imaging methods resulting in a much more complex etiological view of the disorder. The original temporal sampling framework implicates disrupted neural entrainment to speech as a causal factor for atypical phonological representations. Yet, empirical findings have not provided clear evidence of a low-level etiology for this endophenotype. In contrast, the neural noise hypothesis presents a theoretical view of the manifestation of dyslexia from the level of genes to behavior. However, its relative novelty (published in 2017) means that empirical research focused on specific predictions is sparse. The current paper reviews dyslexia research using a dual framework from the temporal sampling and neural noise hypotheses and discusses the complementary nature of these two views of dyslexia. We present an argument for an integrated model of sensory temporal sampling as an etiological pathway for dyslexia. Finally, we conclude with a brief discussion of outstanding questions.

Do developmental dyslexia and congenital amusia share underlying impairments?

Developmental dyslexia and congenital amusia have common characteristics. Yet, their possible association in some individuals has been addressed only scarcely. Recently, two converging studies reported a sizable comorbidity rate between these two neurodevelopmental disorders (Couvignou et al., Cognitive Neuropsychology 2019; Couvignou & Kolinsky, Neuropsychologia 2021). However, the reason for their association remains unclear. Here, we investigate the hypothesis of shared underlying impairments between dyslexia and amusia. Fifteen dyslexic children with amusia (DYS+A), 15 dyslexic children without amusia (DYS-A), and two groups of 25 typically developing children matched on either chronological age (CA) or reading level (RL) were assessed with a behavioral battery aiming to investigate phonological and pitch processing capacities at auditory memory, perceptual awareness, and attentional levels. Overall, our results suggest that poor auditory serial-order memory increases susceptibility to comorbidity between dyslexia and amusia and may play a role in the development of the comorbid phenotype. In contrast, the impairments observed in the DYS+A children for auditory item memory, perceptual awareness, and attention might be a consequence of their reduced reading experience combined with weaker musical skills. Comparing DYS+A and DYS-A children suggests that the latter are more resourceful and/or have more effective compensatory strategies, or that their phenotype results from a different developmental trajectory. We will discuss the relevance of these findings for delving into the etiology of these two developmental disorders and address their implications for future research and practice.

What Components of Working Memory Are Impaired in Children with Reading and/or Mathematics Difficulties?

Both reading difficulties (RD) and mathematics difficulties (MD) are common neurodevelopmental disorders. The co-occurrence of RD and MD, known as comorbid RDMD, is estimated to range between 21% and 45% of children with learning disabilities. Deficits in working memory have been reported in both RD and MD groups, as well as among comorbid RDMD. However, previous comorbidity studies have only examined the role of some components of working memory, and they do not strictly match their groups on relevant reading and mathematics tasks. Thus, the purpose of this study is to examine the nature of working memory deficits in comorbid RDMD after matching groups based on reading and mathematics tasks. We assessed four groups of children (RD [n = 21, Mage = 10.96 years], MD [n = 24, Mage = 11.04 years], comorbid RDMD [n = 26, Mage = 10.90 years], and chronological-age controls [n = 27, Mage = 10.96 years]) on measures of the phonological loop (word span and digit span forward tasks), central executive (complex word and digit span), and updating tasks (word and digit 2-back). The results of ANCOVA (covarying for gender and non-verbal IQ) showed first that the RD and RDMD groups performed significantly worse than the MD and control groups in both measures of the phonological loop. For the central executive and updating tasks, we found an effect based on stimulus type. For word-related tasks, the RD and comorbid RDMD groups performed worse than the MD and control groups, and for number-related tasks, the MD and comorbid RDMD groups performed worse than the RD and control groups. Taken together, our findings provide support for the correlated liability model of comorbidity, which indicates that working memory deficits experienced by the RDMD group are an additive combination of deficits observed in the RD and MD groups, suggesting that working memory tasks used to examine underlying deficits in reading and/or mathematics difficulties may dictate whether or not significant group differences are found.

Specific Learning Disorders (SLD) and Behavior Impairment: Comorbidity or Specific Profile?

INTRODUCTION

Specific Learning Disorder (SLD) is a neurodevelopmental disorder characterized by difficulties in perceiving and processing verbal and non-verbal information. It is usually accompanied by impaired academic skills leading to school dropout and emotional disturbances, resulting in significant distress and behavioral problems.

METHODS

A cognitive, academic, and emotional-behavioral assessment was performed at T0 and T1 in children and adolescents with SLD. Participants received psychotherapy and speech therapy treatment from T0 to T1.

RESULTS

In SLD, the most compromised cognitive functions were working memory and writing skills. An impact on academic abilities was found. Children and adolescents with SLD experience greater anxiety and depression levels compared to their control peers.

CONCLUSIONS

SLD may adversely influence psychological well-being. To counteract such a consequence, more specific cognitive and academic skill-oriented strategies should be taken into consideration.

Cognitive Profiles of Children with Isolated and Comorbid Learning Difficulties in Reading and Math: a Meta-analysis

The causes underlying comorbid learning difficulties in reading (RD) and math (MD) are still a matter of debate. Based on current research, two models for the relation of the cognitive profile of isolated and combined learning difficulties (RDMD) are discussed. Regarding the “multi-deficit model”, the profile of RDMD is characterized by the sum of domain-specific core deficits of RD and MD (additivity) as well as shared domain-general risk factors of RD and MD resulting in less severe deficits than expected under additivity (under-additivity). The “three independent disorders model” explains RDMD as a distinct learning disorder, showing a separate cognitive profile with distinct and/or more severe deficits, compared to the sum of RD’s and MD’s profiles (over-additivity). To evaluate these approaches, a meta-analysis including 74 studies, examining children aged 6–12, was conducted. Separate group comparisons for the three subcomponents in the cognitive profiles—reading, math, executive functions (EF)—were considered. Linear hypothesis testing revealed different results regarding the three subcomponents of the cognitive profiles of children with isolated vs. combined learning difficulties: Whereas RDMDs’ deficits in reading and math represented the sum of the deficits in the isolated groups (additivity), there was some evidence that RDMDs’ deficits in EF skills corresponded to under-additivity. Furthermore, group differences in math skills were more pronounced in symbolic than in non-symbolic math tasks, whereas in reading, group differences were larger in phonological processing and reading than in rapid automatized naming and language skills. Results are discussed in terms of intervention options for RDMD.

The effect of anxiety on working memory and language abilities in elementary schoolchildren with and without Additional Health and Developmental Needs

Although excessive childhood anxiety is recognised as a significant public health, education and socioeconomic concern, the specific effects of such anxiety on language development and working memory, particularly visual working memory, are relatively unknown. Thus, this study aimed to examine parent-reported trait anxiety, parent-reported functional language (daily communication skills) and clinical measures of non-verbal intelligence, receptive and expressive vocabulary, phonological awareness, and visual and auditory-verbal short-term and working memory in elementary schoolchildren. The final sample included 41 children categorised as Additional Health and Developmental Needs (AHDN) due to medical, neurodevelopmental or educational concerns and 41 age- and IQ-matched neurotypical (NT) children, aged 5- to 9-years. Results showed that 26% of all children in our entire sample (AHDN and NT) experienced moderate, sub-clinical anxiety (as reported by parents), and that AHDN children were 10.5 times more likely to experience high anxiety than the NT group (odds ratio). Parents of AHDN children reported lower functional language in their children than parents of NT children. Cognitive testing indicated that the AHDN group also had poorer visual and auditory-verbal working memory than the NT group. Further, High Anxiety children (drawn from both AHDN and NT groups) showed poorer parent-reported functional language skills, and lower visual and auditory-verbal working memory capacities. Our findings are amongst the first to confirm that the presence of high parent-rated trait anxiety is associated with reduced visual working memory in children, which is consistent with biological and theoretical expectations of the impact of anxiety on visually driven, goal-directed attention and working memory. Our results regarding the high prevalence of sub-clinical anxiety in both ADHD and neurotypical children highlight the need for early assessment of anxiety in all schoolchildren, especially those classified as AHDN.

WISC-IV and Rey Auditory Verbal Learning Test Indicators of Specific Learning Disorder and Discrepant Academic Achievement

Though several studies have been undertaken to explore the correlates of academic achievement, there is a dearth of studies relating to the cognitive profiles of children who show marked discrepancies between their cognitive potential and actual academic achievement. The present study was undertaken in this context. The study was conducted on a sample of 308 students in the age range of 12–16 years, drawn from different schools in Kerala, India. The participants belonged to four groups, that is, Underachievers, Normal achievers, Overachievers, and those with Specific Learning Disorders (SLD). WISC-IV India and Rey Auditory Verbal Learning Test (RAVLT) were used for assessing cognitive functions. Results indicated that the SLD group could be discriminated from the other three groups in terms of Digit span, Letter-Number sequencing, Working Memory Index, and Processing Speed Index. Further, a retention score obtained from RAVLT could discriminate between the SLD and UA groups. Discriminant analysis of the variables resulted in the extraction of two significant functions composed of three variables of WISC and two variables of RAVLT. The results indicated that the different groups of scholastically backward children, though similar in their overall IQ, had distinct and characteristic cognitive profiles.

Interpersonal Adaptation, Self-Efficacy, and Metacognitive Skills in Italian Adolescents with Specific Learning Disorders: A Cross-Sectional Study

This study aimed to explore interpersonal adaptation, generalized self-efficacy, and metacognitive skills in a sample of Italian adolescents with and without a specific learning disorder (SLD). A total of 564 secondary and high school students (males = 236; females = 328; age range: 11–19; M = 16.14, SD = 1.70) completed a set of standardized tests assessing social and interpersonal skills (non-affirmation, impulsiveness, narcissism, social preoccupation, and stress in social situations), general self-efficacy, and metacognition. Students with SLD reported a lower interpersonal adaptation than students without SLD. Furthermore, students with SLD were more impulsive and had more problems handling social situations. They also reported lower levels of self-efficacy but higher metacognition scores than peers without SLD. The use of compensatory tools was associated with better interpersonal skills and higher levels of self-efficacy in students with SLD. Finally, using these instruments is predictive of high levels of metacognitive skills in adolescents with SLD. In line with the previous literature, this study showed the presence of a gap between adolescents with and without an SLD in terms of interpersonal adaptation, general self-efficacy, and metacognitive skills in the school context. Further studies are needed on the psychological well-being of adolescents with SLD and especially on the protective role of personal, social, and environmental characteristics.

The Cognitive Profile of Math Difficulties: A Meta-Analysis Based on Clinical Criteria

Math difficulties (MD) manifest across various domain-specific and domain-general abilities. However, the existing cognitive profile of MD is incomplete and thus not applicable in typical settings such as schools or clinics. So far, no review has applied inclusion criteria according to DSM or ICD, summarized domain-specific abilities or examined the validity of response time scores for MD identification. Based upon stringent clinical criteria, the current meta-analysis included 34 studies which compared cognitive performances of a group with MD (n = 680) and a group without MD (n = 1565). Criteria according to DSM and ICD were applied to identify MD (percentile rank ≤ 16, age range 8–12 years, no comorbidities/low IQ). Effect sizes for 22 abilities were estimated and separated by their level and type of scoring (AC = accuracy, RT = response time). A cognitive profile of MD was identified, characterized by distinct weaknesses in: (a) computation (calculation [AC], fact retrieval [AC]), (b) number sense (quantity processing [AC], quantity-number linking [RT], numerical relations [AC]), and (c) visual-spatial short-term storage [AC]. No particular strength was found. Severity of MD, group differences in reading performance and IQ did not significantly moderate the results. Further analyses revealed that (a) effects are larger when dealing with numbers or number words than with quantities, (b) MD is not accompanied by any weakness in abilities typically assigned to reading, and (c) weaknesses in visual-spatial short-term storage emphasize the notion that number and space are interlinked. The need for high-quality studies investigating domain-general abilities is discussed.

Phonological working memory and central executive function differ in children with typical development and dyslexia

The primary purpose of this study was to compare the working memory performance of monolingual English-speaking second^- grade children with dyslexia (N = 82) to second-grade children with typical development (N = 167). Prior to making group comparisons, it is important to demonstrate invariance between working memory models in both groups or between-group comparisons would not be valid. Thus, we completed invariance testing using a model of working memory that had been validated for children with typical development (Gray et al., 2017) to see if it was valid for children with dyslexia. We tested three types of invariance: configural (does the model test the same constructs?), metric (are the factor loadings equivalent?), and scalar (are the item intercepts the same?). Group comparisons favoured the children with typical development across all three working memory factors. However, differences in the Focus-of-Attention/Visuospatial factor could be explained by group differences in non-verbal intelligence and language skills. In contrast, differences in the Phonological and Central Executive working memory factors remained, even after accounting for non-verbal intelligence and language. Results highlight the need for researchers and educators to attend not only to the phonological aspects of working memory in children with dyslexia, but also to central executive function.

Lernstörungen: Ein unvermeidbares Schicksal?

Zusammenfassung. Etwa jedes dritte Kind in Deutschland leidet im Laufe der Grundschule unter besonderen Lernschwierigkeiten beim Erwerb von Lesen, Rechtschreiben und Rechnen. Mindestens jedes achte Grundschulkind erfüllt sogar die Kriterien der Weltgesundheitsorganisation für die Vergabe der Diagnose „Lernstörung“. In diesem Beitrag wird erläutert, was unter Lernstörungen im Einzelnen zu verstehen ist und was über die biogenetischen und sozialen (einschließlich didaktischen) Risiken für das Entstehen von Lernstörungen bekannt ist. Außerdem wird auf den Forschungsstand zu der Frage eingegangen, welche eingeschränkten kognitiven Funktionen mit einem hohen individuellen Risiko für das Entstehen einer Lernstörung einhergehen. Es folgt ein Überblick über den Forschungsstand zu (vorschulischen) Präventionsansätzen, die sich als wirksam zur Vermeidung von Lernstörungen erwiesen haben, und zur Frage, welche Interventionsansätze bei Auftreten besonderer Lernschwierigkeiten beim Erwerb von Schriftsprache und Mathematik in der Schule am ehesten geeignet sind, diese zu überwinden. Darauf aufbauend werden abschließend Vorschläge zu einer sequentiellen Strategie für die weitgehende Vermeidung von Lernstörungen und ihren negativen Langzeitfolgen unterbreitet und die Potenziale digitaler diagnosebasierter Förderprogramme diskutiert.

The Influence of Articulatory Suppression on Reading Among Chinese Children With Developmental Dyslexia: An Eye-Movement Study

Objective: The study aimed to examine how the phonological loop influences reading ability and processing in Chinese children with developmental dyslexia (DD). Methods: This study included 30 children with DD and 37 children without DD. Two types of articles (i.e., scenery prose and narrative story) and two conditions (under the conditions of articulatory-suppression and silent reading) were applied. An eye-link II High-Speed Eye Tracker was used to track a series of eye-movement parameters. The data were analyzed by the linear Mixed-Effects model. Results: Compared with children without DD, Children with DD had lower reading achievement (RA), frequency of saccades (FS) and frequency of fixations (FF), longer reading time (RT) and average fixation duration (AFD), slower reading speed (RS), shorter average saccade amplitude (ASA) and fixation distance (FD), more number of fixations (NF), and number of saccades (NS). There were significant interactions between participant group and articulatory suppression on RT and FD. We also observed interaction effects between article types and articulatory suppression on RA, AFD, ASA, and FS. Conclusion: Children DD exhibit abnormal phonological loop and eye movements while reading. The role of articulatory suppression on reading varies with the presentation of DD and the article type.

The association between anxiety and academic performance in children with reading disorder: A longitudinal cohort study

The purpose of this study was to examine the association between anxiety and overall academic performance (AP) in children with reading disorder (RD). This two-year longitudinal cohort study included 128 participants (aged 7-14 years) with RD. Anxiety symptoms were evaluated using the School Anxiety Scale - Teacher Report for the first year and the eight-item Spence Children's Anxiety Scale for the second year. AP was assessed by teacher ratings of progress in academic content areas, including reading, writing and math. Teachers completed evaluations every 3 months. We standardized all scores (to z scores). Multivariate linear regression models (adjusting for age, sex and Attention-Deficit/Hyperactivity Disorder symptoms) assessed the association cross-sectionally at each timepoint of survey completion. Repeated measures analysis using mixed models assessed the relationship longitudinally. Results from both univariate and multivariate analyses showed anxiety being significantly negatively associated with AP in children with RD, both cross-sectionally and longitudinally. Importantly, increased anxiety was significantly associated with reduced AP over time within an individual (adjusted β = -0.22, p = .002). This lends support to screening for anxiety disorders in children with RD. Future research should examine the directionality of this relationship, potential mediators in the pathway and whether interventions to reduce anxiety increase AP.

Diagnostik von Lernstörungen: Zeit zum Umdenken

Zusammenfassung. Lernschwierigkeiten beim Erwerb der Schriftsprache oder des Rechnens gehört für ca. ein Drittel aller Grundschulkinder zum schulischen Alltag. Wenn diese Schwierigkeiten länger andauern, wird von Lernschwächen, Lernstörungen oder Lernbehinderungen gesprochen. Die begriffliche Abgrenzung wird aktuell durch verschiedene Klassifikationskriterien in verschiedenen Klassifikationssystemen (ICD-10/11, DSM-5 oder AWMF Leitlinien) sehr erschwert, was Unsicherheiten in der Diagnostik und auch divergierende pädagogische Konsequenzen zur Folge hat. Eine besondere Rolle spielt dabei das sogenannte doppelte Diskrepanzkriterium für die Diagnose einer Lernstörung: Die Leistung eines Kindes muss unter dem nach dem Alter bzw. der Beschulung und der Intelligenz zu erwartenden Niveau liegen. Die Schulleistung muss also erwartungswidrig ausfallen – das betroffene Kind bleibt hinter den für die Klassenstufe typischen Leistungen und auch hinter den eigenen allgemeinen kognitiven Fähigkeiten zurück. Das Kriterium der Diskrepanz der Schulleistung zur Intelligenz wird seit langem kontrovers diskutiert und ist in den Klassifikationssystemen unterschiedlich verankert. Seine Anwendung hat sowohl für die diagnostische als auch für die pädagogische Praxis weitreichende Konsequenzen. Es führt dazu, dass Kinder mit Diskrepanz zwischen Schulleistung und Intelligenz die Diagnose „Lernstörung“ erhalten, Kinder ohne diese Diskrepanz haben eine „Lernschwäche“, beide Gruppen erfahren unterschiedliche schulische und außerschulische Lernförderung. Der vorliegende Beitrag stellt die Berechtigung dieses Kriteriums der Diskrepanz zwischen Schulleistung und Intelligenz anhand empirischer Evidenz in Frage und beleuchtet Konsequenzen sowohl für die bislang gängige Anwendung des doppelten Diskrepanzkriteriums als auch für den Verzicht darauf. Das Fazit dieser Erörterung rät zum Umdenken.

Effects of Neurofeedback on the Working Memory of Children with Learning Disorders-An EEG Power-Spectrum Analysis

Learning disorders (LDs) are diagnosed in children impaired in the academic skills of reading, writing and/or mathematics. Children with LDs usually exhibit a slower resting-state electroencephalogram (EEG), corresponding to a neurodevelopmental lag. Frequently, children with LDs show working memory (WM) impairment, associated with an abnormal task-related EEG with overall slower EEG activity (more delta and theta power, and less gamma activity in posterior sites). These EEG patterns indicate inefficient neural resource management. Neurofeedback (NFB) treatments aimed at normalizing the resting-state EEG of LD children have shown improvements in cognitive-behavioral indices and diminished EEG abnormalities. Given the typical findings of WM impairment in children with LDs, we aimed to explore the effects of an NFB treatment on the WM of children with LDs by analyzing the WM-related EEG power spectrum. EEGs of 18 children (8–11 y.o.) with LDs were recorded, pre- and post-treatment, during performance of a Sternberg-type WM task. Thirty sessions of an NFB treatment (NFB-group, n = 10) or 30 sessions of a placebo-sham treatment (sham-group, n = 8) were administered. We analyzed the before and after treatment group differences for the behavioral performance and the WM-related EEG power spectrum. The NFB group showed faster response times in the WM task post-treatment. They also exhibited a decreased theta power and increased beta and gamma power at the frontal and posterior sites post-treatment. We explain these findings in terms of NFB improving the efficiency of neural resource management, maintenance of memory representations, and improved subvocal memory rehearsal.

Two Dyscalculia Subtypes With Similar, Low Comorbidity Profiles: A Mixture Model Analysis

Several studies have aimed to identify subtypes of dyscalculia. In many of these studies, either pre-defined groups (e.g., children with reading and mathematical difficulties vs. children with isolated mathematical difficulties) were analyzed regarding their cognitive profiles (top-down approach), or clusters of children with dyscalculia (CwD) were identified based on a narrow range of cognitive and mathematical skills (data-driven or bottom-up approach). However, it has remained difficult to establish robust subtypes of dyscalculia across studies. Against this background, we conducted a mixture model analysis in order to explore and identify subtypes of dyscalculia based on a broad range of variables (intelligence, reading fluency, working memory, attention, and various mathematical skills). The total sample comprised 174 elementary school CwD (IQ > 70; mathematical abilities: percentile rank <10), which consisted of two subsamples. The first subsample was based on a diagnostic test focusing on calculation (HRT 1–4; n = 71; 46 girls, 25 boys; age: M = 9.28 years, SD = 0.94) whereas the second subsample was based on a diagnostic test with a strong focus on basic numerical capacities (ZAREKI-R; n = 103; 78 girls, 25 boys; age: M = 8.94 years, SD = 1.05). Results provided convincing evidence for the existence of two subtypes in CwD: A slightly impaired subtype and a strongly impaired subtype. Subtypes differed most strongly regarding mathematical abilities, but the analyses suggest that differences in attention could also be a key factor. Therefore, comorbid attention difficulties seem to be a relevant factor that needs to be considered when establishing subtypes. Substantial intelligence differences between dyscalculia subtypes could not be found. Differences in working memory and reading fluency were negligible. Overall, the results seemed to be robust regardless of the diagnostic test used for assessing dyscalculia. When planning interventions for CwD, the existence of a subtype with substantial attention problems should be kept in mind.

The Modularity of Dyslexia

There is a growing interest in understanding dyslexia and the mechanisms involved in reading difficulties. Inquiries into the morphological and physiological changes of the brain have contributed to our increased understanding of reading ability and dyslexia. Similarly, inquiries into brain chemistry and reading provide a neurometabolic framework of dyslexia in terms of poor reading and phonological measures. Also, studies of the genetic etiology of reading yield substantial evidence of genes and SNPs associated with dyslexia. However, little is known about the interface between these distinct areas of knowledge. Therefore, we offer an exhaustive perspective on dyslexia using the idea of modularity by assimilating the findings and implications from the brain morphological, neurophysiological, neurochemical, genetic, and educational insights into dyslexia. We contend that this endeavor will provide a beneficial foundation for aiming at the possibilities of a holistic intervention and informed solutions for reading difficulties.

Executive Functioning with the NIH EXAMINER and Inference Making in Struggling Readers

Executive functioning (EF) is a domain-general process implicated in reading, but there remains lack of clarity within the domain due to varied assessment methods. We investigated the relation of EF (indexed with the NIH EXAMINER) to word reading, reading fluency, and reading comprehension in struggling readers and evaluated the mediational role of inference making for the EF-comprehension link. Analyses revealed an overall effect of EF on reading, with significant differences between fluency and comprehension, and between single word reading and comprehension, but not between fluency and single-word reading. The EF-reading comprehension relation was fully mediated by inference making.

Arithmetic processing in children with dyscalculia: an event-related potential study

Introduction

Dyscalculia is a specific learning disorder affecting the ability to learn certain math processes, such as arithmetic data recovery. The group of children with dyscalculia is very heterogeneous, in part due to variability in their working memory (WM) deficits. To assess the brain response to arithmetic data recovery, we applied an arithmetic verification task during an event-related potential (ERP) recording. Two effects have been reported: the N400 effect (higher negative amplitude for incongruent than for congruent condition), associated with arithmetic incongruency and caused by the arithmetic priming effect, and the LPC effect (higher positive amplitude for the incongruent compared to the congruent condition), associated with a reevaluation process and modulated by the plausibility of the presented condition. This study aimed to (a) compare arithmetic processing between children with dyscalculia and children with good academic performance (GAP) using ERPs during an addition verification task and (b) explore, among children with dyscalculia, the relationship between WM and ERP effects.

Materials and Methods

EEGs of 22 children with dyscalculia (DYS group) and 22 children with GAP (GAP group) were recorded during the performance of an addition verification task. ERPs synchronized with the probe stimulus were computed separately for the congruent and incongruent probes, and included only epochs with correct answers. Mixed 2-way ANOVAs for response times and correct answers were conducted. Comparisons between groups and correlation analyses using ERP amplitude data were carried out through multivariate nonparametric permutation tests.

Results

The GAP group obtained more correct answers than the DYS group. An arithmetic N400 effect was observed in the GAP group but not in the DYS group. Both groups displayed an LPC effect. The larger the LPC amplitude was, the higher the WM index. Two subgroups were found within the DYS group: one with an average WM index and the other with a lower than average WM index. These subgroups displayed different ERPs patterns.

Discussion

The results indicated that the group of children with dyscalculia was very heterogeneous and therefore failed to show a robust LPC effect. Some of these children had WM deficits. When WM deficits were considered together with dyscalculia, an atypical ERP pattern that reflected their processing difficulties emerged. Their lack of the arithmetic N400 effect suggested that the processing in this step was not useful enough to produce an answer; thus, it was necessary to reevaluate the arithmetic-calculation process (LPC) in order to deliver a correct answer.

Conclusion

Given that dyscalculia is a very heterogeneous deficit, studies examining dyscalculia should consider exploring deficits in WM because the whole group of children with dyscalculia seems to contain at least two subpopulations that differ in their calculation process.

Executive Functions in Neurodevelopmental Disorders: Comorbidity Overlaps Between Attention Deficit and Hyperactivity Disorder and Specific Learning Disorders

The present study examines the comorbidity between specific learning disorders (SLD) and attention deficit and hyperactivity disorder (ADHD) by comparing the neuropsychological profiles of children with and without this comorbidity. Ninety-seven schoolchildren from 8 to 14 years old were tested: a clinical sample of 49 children with ADHD (n = 18), SLD (n = 18) or SLD in comorbidity with ADHD (n = 13), and 48 typically-developing (TD) children matched for age and intelligence. Participants were administered tasks and questionnaires to confirm their initial diagnosis, and a battery of executive function (EF) tasks testing inhibition, shifting, and verbal and visuospatial updating. Using one-way ANOVAs, our results showed that all children in the clinical samples exhibited impairments on EF measures (inhibition and shifting tasks) when compared with TD children. A more specific pattern only emerged for the updating tasks. Only children with SLD had significant impairment in verbal updating, whereas children with ADHD, and those with SLD in comorbidity with ADHD, had the worst performance in visuospatial updating. The clinical and educational implications of these findings are discussed.

Impaired large numerosity estimation and intact subitizing in developmental dyscalculia

It is believed that the approximate estimation of large sets and the exact quantification of small sets (subitizing) are supported by two different systems, the Approximate Number System (ANS) and Object Tracking System (OTS), respectively. It is a current matter of debate whether they are both impaired in developmental dyscalculia (DD), a specific learning disability in symbolic number processing and calculation. Here we tackled this question by asking 32 DD children and 32 controls to perform a series of tasks on visually presented sets, including exact enumeration of small sets as well as comparison of large, uncountable sets. In children with DD, we found poor sensitivity in processing large numerosities, but we failed to find impairments in the exact enumeration of sets within the subitizing range. We also observed deficits in visual short-term memory skills in children with dyscalculia that, however, did not account for their low ANS acuity. Taken together, these results point to a dissociation between quantification skills in dyscalculia, they highlight a link between DD and low ANS acuity and provide support for the notion that DD is a multifaceted disability that covers multiple cognitive skills.

Cognitive correlates of dyslexia, dyscalculia and comorbid dyslexia/dyscalculia: Effects of numerical magnitude processing and phonological processing

Specific learning disorders (i.e., dyscalculia and dyslexia) are common, as is their comorbidity. It has been suggested that the core cognitive deficit in dyscalculia is an impairment in numerical magnitude processing; similarly, in dyslexia, phonological processing deficits are considered to be the main cognitive deficit. Cognitive theories on comorbid dyslexia/dyscalculia have suggested a number of hypotheses about which cognitive deficits underlie the comorbidity. However, few studies have thus far directly compared the abovementioned cognitive correlates of dyscalculia and dyslexia. In this study, we assessed symbolic and non-symbolic numerical magnitude and three subcomponents of phonological processing (phonological awareness, lexical access and verbal short-term memory). In addition, we investigated children's domain-general spatial and verbal skills. The effect of these cognitive correlates on dyscalculia, dyslexia and their comorbidity was explored. We did not find differences between children with and without dyscalculia on numerical magnitude processing. On the other hand, children with dyscalculia had significantly lower spatial skills compared to children without dyscalculia. Children with dyslexia performed significantly lower on all subcomponents of phonological processing. Finally, we found an additive effect for comorbid dyslexia/dyscalculia: impairments in children with co-occurring dyslexia and dyscalculia were similar to the sum of the impairments in the isolated dyslexia and isolated dyscalculia groups. The strongest unique predictor of isolated dyscalculia and comorbid dyslexia/dyscalculia was spatial skills, the strongest unique predictor of isolated dyslexia was phonological awareness. As only a limited number of cognitive variables were assessed in this study and the sample sizes were very small, we should be cautious when interpreting these results.

A comparative study of executive functions among children with attention deficit and hyperactivity disorder and those with learning disabilities

Background

Both ADHD and learning disorders have been found to be associated with executive dysfunctions; the executive functions’ (EFs) construct generally involves a series of components—planning, cognitive flexibility, inhibition, attention control, and verbal and visuo-spatial working memory—that work independently in many ways but are closely related. There were no significant studies comparing both disorders and excluding the drug’s effects on executive functions. In our study, we used BDEFS-CA to assess executive functions among a sample of 340 children divided in to four groups: group 1 (100 children), ADHD only; group II (80 children), LD only; group III (60 children), combined ADHD and LD; and group IV (100 children), control group. We included children aged from 6 to 13 of both sexes of average IQ and all had to be drug naive with no sensory impairment or disabling neurological disorder and after their parents’ consent.

Results

The results showed that there was significant higher affection of the five executive functions domains in the first three groups more than the fourth control group. Furthermore, the self-restraint (response-inhibition) executive dysfunction was the most commonly affected EF in group I while time management EF and self-regulation and problem solving EF were the most commonly affected EF in the LD group.

Conclusions

Complete executive function profile assessment should be done for children diagnosed with ADHD or learning disability and EF intervention program should be included in the management plan for better outcomes mainly self-restraint EF in case of ADHD and problem solving and self-organization EF in case of learning disabilities

Working Memory in Children with Learning Disorders: An EEG Power Spectrum Analysis

Learning disorders (LDs) are diagnosed in children whose academic skills of reading, writing or mathematics are impaired and lagging according to their age, schooling and intelligence. Children with LDs experience substantial working memory (WM) deficits, even more pronounced if more than one of the academic skills is affected. We compared the task-related electroencephalogram (EEG) power spectral density of children with LDs (n = 23) with a control group of children with good academic achievement (n = 22), during the performance of a WM task. sLoreta was used to estimate the current distribution at the sources, and 18 brain regions of interest (ROIs) were chosen with an extended version of the eigenvector centrality mapping technique. In this way, we lessened some drawbacks of the traditional EEG at the sensor space by an analysis at the brain-sources level over data-driven selected ROIs. Results: The LD group showed fewer correct responses in the WM task, an overall slower EEG with more delta and theta activity, and less high-frequency gamma activity in posterior areas. We explain these EEG patterns in LD children as indices of an inefficient neural resource management related with a delay in neural maturation.

Cognitive and Behavioural Weaknesses in Children with Reading Disorder and AD(H)D

Working memory capacity, an essential prerequisite for language learning and the development of arithmetic skills, has been reported as deficient in children with reading disorder (RD) and attention deficit (hyperactivity) disorder (AD(H)D). However, few studies to date have explored potential associations of working memory impairments and foreign language learning, mathematical skills and school achievement in these groups, in particular in children with a comorbidity of both. In the present study, we assessed working memory, language learning, arithmetic fluency and academic achievement in children (N = 166; Mage = 14.3, range 8-18 y), including typically-developing children (n = 89), subjects with RD (n = 27), AD(H)D (n = 43), and a comorbidity (n = 15). While children with AD(H)D performed similar to typically developing children on all tasks, RD children performed weakly on various language learning and working memory tasks, with major deficits in non-word span, phonetic memory and vocabulary learning. Combining weaknesses of the two groups, children with a comorbidity further performed significantly worse on arithmetic skills, learning of sound-symbol combinations and simple digit span forward. The findings suggest a reconsideration of working memory and learning impairments in AD(H)D, while highlighting the additional weaknesses of comorbid children and pointing out severe foreign language learning difficulties in RD children.

Intellectual functioning and executive functions in children and adolescents with attention deficit hyperactivity disorder (ADHD) and specific learning disorder (SLD)

Several studies have shown neuropsychological deficits across multiple domains in attention deficit hyperactivity disorder (ADHD) and specific learning disorder (SLD), but differences and similarities between these disorders have been little considered. We were interested in analyzing the intellectual and executive profiles in a sample of children and adolescents, divided according to the diagnosis into the ADHD group and the SLD group, and in identifying the differences and similarities between these disorders. The sample included two clinical groups: the first included 36 children and adolescents with a diagnosis of ADHD (5-15 years; mean = 9.42; SD = 2.22) while the second included 36 children and adolescents with a diagnosis of SLD (7-15 years; mean = 9.43; SD = 2.25). The WISC-IV was used to measure intellectual ability and the NEPSY-II was employed to measure executive functions. The results showed that the SLD group had significantly higher scores than the ADHD group on the NEPSY-II in the inhibition, cognitive flexibility, short-term verbal memory and verbal working memory domains. The ANCOVA showed differences regarding the FSIQ of WISC-IV, in that the SLD group obtaining higher scores than ADHD group. Findings showed that ADHD children are more impaired than SLD children, in particular in cognitive inhibition, cognitive flexibility, verbal memory, working memory and intellectual functioning. The recognition of the strengths and weaknesses of children and adolescents with ADHD and SLD allows to outline an educational and clinical intervention focused on their specific executive and intellectual functioning.

Co-occurrence of Reading Disabilities and Math Disabilities: A Meta-Analysis

Despite the importance of identifying individuals with reading disabilities, existing operational definitions of reading disability do not result in reliable identification. A large part of the problem arises from measurement error when a cut-point is imposed on a continuous distribution, especially for low base-rate conditions. One way to reduce measurement error is to include additional predictors in reading disability models. The present study examined co-occurring math disability as a possible additional criterion for predicting reading disability. Meta-analysis was used to examine the probability of individuals with reading disability also having a comorbid math disability. Possible moderators including age, severity of disability, and language were examined. The main result was an average weighted odds ratio of 2.12, 95% confidence interval [1.76, 2.55], indicating that students with a math disability are just over two times more likely to also have a reading disability than those without a math disability. Implications of the results are discussed.

Training Working Memory of Children with and without Dyslexia

For the future school performance of a child in the fields of literacy and numeracy, the operational efficiency of working memory is a central predictor. Children affected by dyslexia exhibit specific deficits in the functions of working memory. A software application for elementary school-age children has been specifically developed for this study, attempting to improve the working memory's operational efficiency. Based on Baddeley's model of working memory (1986), the phonological loop, the visuo-spatial sketchpad, and the central executive were trained in 18 sessions over a period of six weeks. The group of test subjects undergoing this training was composed of third-graders, of which 43 were and 27 were not affected by dyslexia. The untrained control group was made up of 41 third-graders with dyslexia and 28 without dyslexia. While the short-term effects of the program could not be proven, the present analyses focus on long-term effects. The results obtained from a pre-test/follow-up design reveal that no long-term increases in performance regarding phonological and central executive working memory could be confirmed. Only the visuo-spatial Corsi block span exhibited a training effect over a period of three months. Additionally, training did not show any long-term effect of performance improvement, not even for a subgroup of children with dyslexia and an especially low working memory performance. Thus, even after this study, the question whether working memory can be trained or not remains partly unanswered but leaves us predominantly pessimistic.

Effects of a Motor Intervention Program on Motor Skills and Executive Functions in Children With Learning Disabilities

This study examined the effect of a motor intervention based on the attention, balance, and coordination (ABC) learning approach on motor proficiency and executive functions in children with learning disabilities (LD). Forty-five male elementary school students with LD aged 7-9 years were recruited and randomly assigned into one of three groups: two experimental groups and one control group. Experimental Group A received only the motor intervention. Experimental Group B simultaneously received both motor intervention and regular educational services. The control group received only regular educational services. The motor intervention involved sequential station exercises based on ABC; this training took place in 24 sessions, scheduled three times a week for eight weeks. We obtained children's scores on the Bruininks-Oseretsky Tests of Motor Proficiency, N-Back Test, Tower of London, and Continuous Performance Tests at pretest, posttest, and follow-up testing. Our results showed that both experimental groups significantly improved their motor skills and most measures of executive functions, relative to no significant improvement for the control group. The improvements on some measures of executive functions in Experimental Group B were just slightly better than in Experimental Group A. This study supported Blythe's ABC learning approach emphasizing ABC, and it extended earlier findings of benefits of this approach to populations of children with LD.

Understanding comorbidity of learning disorders: task-dependent estimates of prevalence

BACKGROUND

Reading disorder (RD) and mathematics disorder (MD) frequently co-occur. However, the exact comorbidity rates differ largely between studies. Given that MD is characterised by high heterogeneity on the symptom level, differences in comorbidity rates may result from different mathematical subskills used to define MD. Comorbidity rates with RD are likely to be higher when MD is measured by mathematical subskills that do not only build on number processing, but also require language (i.e. arithmetic fluency), than when measured by magnitude processing skills.

METHODS

The association between literacy, arithmetic fluency and magnitude processing as well as the overlap between deficits in these domains were assessed in a representative sample of 1,454 third Graders.

RESULTS

Associations were significantly higher between literacy and arithmetic, than between literacy and magnitude processing. This was also reflected in comorbidity rates: comorbidity rates between literacy and arithmetic deficits were four times higher than expected by chance, whereas comorbidity rates between literacy and magnitude processing deficits did not exceed chance rate. Deficits in the two mathematical subskills showed some overlap, but also revealed dissociations, corroborating the high heterogeneity of MD. Results are interpreted within a multiple-deficit framework and implications for diagnosis and intervention are discussed.

CONCLUSIONS

The overlap between RD and MD depends on the subskills used to define MD. Due to shared domain-general factors mathematical subskills that draw on language skills are more strongly associated with literacy than those that do not require language. The findings further indicate that the same symptom, such as deficits in arithmetic, can be associated with different cognitive deficits, a deficit in language skills or a deficit in number processing.

The Diagnosis and Treatment of Dyscalculia

BACKGROUND

3-7% of all children, adolescents, and adults suffer from dyscalculia. Severe, persistent difficulty performing arithmetical calculations leads to marked impairment in school, at work, and in everyday life and elevates the risk of comorbid mental disorders. The state of the evidence underlying various methods of diagnosing and treating this condition is unclear.

METHODS

Systematic literature searches were carried out from April 2015 to June 2016 in the PsycInfo, PSYNDEX, MEDLINE, ProQuest, ERIC, Cochrane Library, ICTRP, and MathEduc databases. The main search terms on dyscalculia were the German terms "Rechenstörung," "Rechenschwäche," and "Dyskalkulie" and the English terms "dyscalculia," "math disorder, and "math disability." The data from the retrieved studies were evaluated in a meta-analysis, and corresponding recommendations on the diagnosis and treatment of dyscalculia were jointly issued by the 20 societies and associations that participated in the creation of this guideline.

RESULTS

The diagnosis of dyscalculia should only be made if the person in question displays below-average mathematical performance when seen in the context of relevant information from the individual history, test findings, clinical examination, and further psychosocial assessment. The treatment should be directed toward the individual mathematical problem areas. The mean effect size found across all intervention trials was 0.52 (95% confidence interval [0.42; 0.62]). Treatment should be initiated early on in the primary-school years and carried out by trained specialists in an individual setting; comorbid symptoms and disorders should also receive attention. Persons with dyscalculia are at elevated risk of having dyslexia as well (odds ratio [OR]: 12.25); the same holds for attention deficit/hyperactivity disorder and for other mental disorders, both internalizing (such as anxiety and depression) and externalizing (e.g., disorders characterized by aggression and rule-breaking).

CONCLUSION

Symptom-specific interventions involving the training of specific mathematical content yield the best results. There is still a need for high-quality intervention trials and for suitable tests and learning programs for older adolescents and adults.

Die Entwicklung von Kindern mit umfassenden Lernschwierigkeiten im Verlauf der Grundschuljahre – Schulleistungen, Arbeitsgedächtnis, phonologische Informationsverarbeitung und Selbstkonzept

Zusammenfassung. Kinder mit Lernschwierigkeiten in der Schriftsprache oder im Rechnen weisen kognitive Defizite auf, welche sich primär auf die schulischen Erfolge auswirken und ferner mit einem schwachen schulischen Selbstkonzept einhergehen. Die vorliegende Arbeit geht der Frage nach, wie sich die Entwicklung der Schulleistungen, des schulischen Selbstkonzepts sowie die Entwicklung zugrundeliegender kognitiver Funktionen (Arbeitsgedächtnisfunktionen nach Baddeley und Hitch (1974) sowie weitere Merkmale der phonologischen Informationsverarbeitung nach Wagner und Torgesen (1987) ) von Kindern mit Lernschwierigkeiten von denen ohne Auffälligkeiten unterscheiden. Dazu wurden in einer Längsschnittstudie über einen Zeitraum von 2 Jahren Grundschulkinder (zu Beginn 8;9 Jahre alt) mit (a) einer Kombinierten Störung schulischer Fertigkeiten bei mindestens durchschnittlicher Intelligenz ( n = 30, IQ ≥ 85) mit (b) Lernschwierigkeiten und unterdurchschnittlicher Intelligenz im Rahmen einer Lernbehinderung ( n = 15, IQ < 85) und mit (c) lernunauffälligen und mindestens durchschnittlich intelligenten Grundschulkindern ( n = 55, IQ ≥ 85) verglichen. Die Ergebnisse zeigen, dass die schulischen Defizite bei beiden Gruppen mit Lernschwierigkeiten zeitlich stabil bestehen blieben. Bezüglich aller Komponenten der kognitiven Funktionen und der Entwicklung des schulischen Selbstkonzepts konnten keine signifikanten Unterschiede zwischen den beiden Lernstörungsgruppen gefunden werden, jedoch unterscheiden sich beide Gruppen signifikant von der Kontrollgruppe. Vor dem Hintergrund dieser Ergebnisse wird diskutiert, inwiefern es sich hier um eine homogene Lernstörungsgruppe handelt.

DIVERGT screening procedure predicts general cognitive functioning in adult long-term survivors of pediatric acute lymphoblastic leukemia: A PETALE study

BACKGROUND

Acute lymphoblastic leukemia (ALL) is the most common cancer in children. Because of major improvements in treatment protocols, the survival rate now exceeds 80%. However, ALL treatments can cause long-term neurocognitive sequelae, which negatively impact academic achievement and quality of life. Therefore, cognitive sequelae need to be carefully evaluated. The DIVERGT is a battery of tests proposed as a screening tool, sensitive to executive function impairments in children and adolescent cancer survivors. Our study aimed at verifying the predictive value of the DIVERGT on general cognitive functioning in adult long-term survivors of ALL.

METHODS

ALL survivors completed the DIVERGT 13.4 years, on average, after remission (N = 247). In addition, 49 of these survivors (equally selected amongst those with low, average, and high DIVERGT scores) as well as 29 controls completed a more comprehensive neuropsychological evaluation within a 3-year period from DIVERGT administration. Multivariate regression analysis was used to assess the predictive value of the DIVERGT on general intelligence, mathematics, verbal memory, and working memory. As a follow-up analysis, three performance groups were created based on the DIVERGT results. Multivariate analysis of variance (MANOVA) assessed neuropsychological differences between groups.

RESULTS

The DIVERGT accurately predicted General Ability Index (GAI) (P < 0.0001), mathematics (P < 0.0001) and verbal memory (P = 0.045). Moreover, the low-performance group consistently had poorer performance than the high-performance and control groups on the neuropsychological tests.

CONCLUSION

The DIVERGT is a useful, time-effective screening battery for broader neurocognitive impairments identification in long-term adult ALL survivors. It could be implemented as routine examination in cancer follow-up clinics.

Dyslexia and dyscalculia are characterized by common visual perception deficits

A number of studies have investigated the cognitive deficits underlying dyslexia and dyscalculia. Yet, it remains unclear as to whether dyslexia and dyscalculia are associated with the common visual perception deficits. The current investigation analyzed cognitive performance in children with dyslexia, dyscalculia, comorbidity, and typically developing subjects. The results showed that children with dyslexia, dyscalculia and comorbidity exhibited common deficits in numerosity processing and visual perception. Furthermore, visual perception deficits accounted for deficits in numerosity processing in all three groups. The results suggest that visual perception deficits are a common cognitive deficit underlying both developmental dyslexia and dyscalculia.

Do Chinese Children With Math Difficulties Have a Deficit in Executive Functioning?

Several studies have shown that Executive Functioning (EF) is a unique predictor of mathematics performance. However, whether or not children with mathematics difficulties (MD) experience deficits in EF remains unclear. Thus, the purpose of this study was to examine if Chinese children with MD experience deficits in EF. We assessed 23 children with MD (9 girls, mean age = 10.40 years), 30 children with reading difficulties and MD (RDMD; 12 girls, mean age = 10.82 years), and 31 typically-developing (TD) peers (16 girls, mean age = 10.41 years) on measures of inhibition (Color-Word Stroop, Inhibition), shifting of attention (Planned Connections, Rapid Alternating Stimuli), working memory (Digit Span Backwards, Listening Span), processing speed (Visual Matching, Planned Search), reading (Character Recognition, Sentence Verification), and mathematics (Addition and Subtraction Fluency, Math Standard Achievement Test). The results of MANOVA analyses showed first that the performance of the MD children in all EF tasks was worse than their TD peers. Second, with the exception of the shifting tasks in which the MD children performed better than the RDMD children, the performance of the two groups was similar in all measures of working memory and inhibition. Finally, covarying for the effects of processing speed eliminated almost all differences between the TD and MD groups (the only exception was Listening Span) as well as the differences between the MD and RDMD groups in shifting of attention. Taken together, our findings suggest that although Chinese children with MD (with or without comorbid reading difficulties) experience significant deficits in all EF skills, most of their deficits can be accounted by lower-level deficits in processing speed.

The modality and redundancy effects in multimedia learning in children with dyslexia

The present study aimed to examine the modality and redundancy effects in multimedia learning in children with dyslexia in order to find out whether their learning benefits from written and/or spoken text with pictures. We compared study time and knowledge gain in 26 11-year-old children with dyslexia and 38 typically reading peers in a within-subjects design. All children were presented with a series of user-paced multimedia lessons in 3 conditions: pictorial information presented with (a) written text, (b) audio, or (c) combined text and audio. We also examined whether children's learning outcomes were related to their working memory. With respect to study time, we found modality and reversed redundancy effects. Children with dyslexia spent more time learning in the text condition, compared with the audio condition and the combined text-and-audio condition. Regarding knowledge gain, no modality or redundancy effects were evidenced. Although the groups differed on working memory, it did not influence the modality or redundancy effect on study time or knowledge gain. In multimedia learning, it thus is more efficient to provide children with dyslexia with audio or with auditory support.

Low Working Memory rather than ADHD Symptoms Predicts Poor Academic Achievement in School-Aged Children

This study examined whether working memory (WM), inattentive symptoms, and/or hyperactive/impulsive symptoms significantly contributed to academic, behavioral, and global functioning in 8-year-old children. One-hundred-sixty 8-year-old children (75.6% male), who were originally recruited as preschoolers, completed subtests from the Wechsler Intelligence Scale for Children-Fourth Edition, Integrated and Wechsler Individual Achievement Test-Second Edition to assess WM and academic achievement, respectively. Teachers rated children's academic and behavioral functioning using the Vanderbilt Rating Scale. Global functioning, as rated by clinicians, was assessed by the Children's Global Assessment Scale. Multiple linear regressions were completed to determine the extent to which WM (auditory-verbal and visual-spatial) and/or inattentive and hyperactive/impulsive symptom severity significantly contributed to academic, behavioral, and/or global functioning. Both auditory-verbal and visual-spatial WM but not ADHD symptom severity, significantly and independently contributed to measures of academic achievement (all p < 0.01). In contrast, both WM and inattention symptoms (p < 0.01), but not hyperactivity-impulsivity (p > 0.05) significantly contributed to teacher-ratings of academic functioning. Further, inattention and hyperactivity/impulsivity (p < 0.04), but not WM (p > 0.10) were significantly associated with teacher-ratings of behavioral functioning and clinician-ratings of global functioning. Taken together, it appears that WM in children may be uniquely related to academic skills, but not necessarily to overall behavioral functioning.

Conservation Abilities, Visuospatial Skills, and Numerosity Processing Speed: Association With Math Achievement and Math Difficulties in Elementary School Children

The aim of the present study was to investigate the associations between elementary school children's mathematical achievement and their conservation abilities, visuospatial skills, and numerosity processing speed. We also assessed differences in these abilities between children with different types of learning problems. In Study 1 ( N = 229), we investigated second to fourth graders and in Study 2 ( N = 120), third and fourth graders. Analyses revealed significant contributions of numerosity processing speed and visuospatial skills to math achievement beyond IQ. Conservation abilities were predictive in Study 1 only. Children with math difficulties showed lower visuospatial skills and conservation abilities than children with typical achievement levels and children with reading and/or spelling difficulties, whereas children with combined difficulties explicitly showed low conservation abilities. These findings provide further evidence for the relations between children's math skills and their visuospatial skills, conservation abilities, and processing speed and contribute to the understanding of deficits that are specific to mathematical difficulties.

When is working memory important for arithmetic? The impact of strategy and age

Our ability to perform arithmetic relies heavily on working memory, the manipulation and maintenance of information in mind. Previous research has found that in adults, procedural strategies, particularly counting, rely on working memory to a greater extent than retrieval strategies. During childhood there are changes in the types of strategies employed, as well as an increase in the accuracy and efficiency of strategy execution. As such it seems likely that the role of working memory in arithmetic may also change, however children and adults have never been directly compared. This study used traditional dual-task methodology, with the addition of a control load condition, to investigate the extent to which working memory requirements for different arithmetic strategies change with age between 9–11 years, 12–14 years and young adulthood. We showed that both children and adults employ working memory when solving arithmetic problems, no matter what strategy they choose. This study highlights the importance of considering working memory in understanding the difficulties that some children and adults have with mathematics, as well as the need to include working memory in theoretical models of mathematical cognition.