Working memory in children with reading disabilities

Reading skills over time among children with Duchenne muscular dystrophy

Duchenne muscular dystrophy (DMD) is an X-linked progressive neuromuscular disorder with a distinct cognitive profile including decreased verbal span. Children with DMD are also at risk for lower scores on academic achievement tests and increased behavioral problems. Longitudinal analyses generally reveal a stable intellectual profile, although attention and behavioral problems may negatively impact longitudinal IQ scores. To date, no study has reported on reading over time in DMD. Reading performance was assessed longitudinally in children with DMD, examining for potential contributions to the trajectory. Retrospective data analysis on assessments completed at baseline, year 2, and year 4 on 26 boys with DMD and 27 unaffected sibling controls (age at baseline: DMD 8 ± 1.4, controls 9 ± 2.6) indicated that children with DMD performed slightly, yet significantly, worse than controls on reading skills, but the longitudinal trajectory of reading skills for children with DMD and controls was not significantly different. Verbal span at time 1 was uniquely associated with later reading skills in children with DMD. Behavior was not associated with declines. The results confirm that children with DMD underperform on reading tasks and align with previous research suggesting that cognitive skills in DMD are stable over time.

Polygenic Risk of Mental Disorders and Subject-Specific School Grades

BACKGROUND

Education is essential for socioeconomic security and long-term mental health; however, mental disorders are often detrimental to the educational trajectory. Genetic correlations between mental disorders and educational attainment do not always align with corresponding phenotypic associations, implying heterogeneity in the genetic overlap.

METHODS

We unraveled this heterogeneity by investigating associations between polygenic risk scores for 6 mental disorders and fine-grained school outcomes: school grades in language and mathematics in ninth grade and high school, as well as educational attainment by age 25, using nationwide-representative data from established cohorts (N = 79,489).

RESULTS

High polygenic liability of attention-deficit/hyperactivity disorder was associated with lower grades in language and mathematics, whereas high polygenic risk of anorexia nervosa or bipolar disorder was associated with higher grades in language and mathematics. Associations between polygenic risk and school grades were mixed for schizophrenia and major depressive disorder and neutral for autism spectrum disorder.

CONCLUSIONS

Polygenic risk scores for mental disorders are differentially associated with language and mathematics school grades.

Recreational gymnastics exercise of moderate intensity enhances executive function in Chinese preschoolers: A randomized controlled trial

The current study aimed to investigate the impact of recreational gymnastics on executive function in Chinese preschoolers, with a focus on gymnastics potential to enhance core components of executive function. A total of 63 preschool children who received full-time education were randomly assigned to either an intervention group (N = 31, mean age = 66.27 months, SD = 3.12 months) or a control group (N = 32, mean age = 66.79 months, SD = 3.34 months). The intervention group engaged in recreational gymnastics for 60 min, three times a week for 12 weeks. Meanwhile, the control group continued with their typical outdoor activities at kindergarten and did not participate in any organized sports. The intervention program was primarily conducted through group play and was facilitated by teachers who underwent standardized training. Various simple and complex tasks were utilized to evaluate delay gratification (Snack delay and Wrapped gift), inhibitory control (Stop signal task and Circle drawing task), working memory (Letter memory task and Keep track task), and cognitive flexibility (Go/No-Go task and Dots task). The analysis of covariance revealed that the children who participated in the intervention outperformed the control group on most simple and complex executive function tasks. Specifically, these children demonstrated an enhanced ability to regulate persistent responses, process and update information, and manage high cognitive conflict. The findings of this investigation lend support to the hypothesis that moderate-intensity recreational gymnastics is an efficacious means of enhancing executive function in early childhood. Future research should employ a larger sample size, incorporate a long-term follow-up design, and utilize a multi-method approach to further substantiate the impact of moderate-intensity gymnastics on the executive function of young children, as well as to investigate its underlying mechanism and generalizability.

Functional connectivity is linked to working memory differences in children with reading learning disability

Reading learning disability (RLD) is characterized by a specific difficulty in learning to read that is not better explained by an intellectual disability, lack of instruction, psychosocial adversity, or a neurological disorder. According to the domain-general hypothesis, a working memory deficit is the primary problem. Working memory in this population has recently been linked to altered resting-state functional connectivity within the default mode network (DMN), salience network (SN), and frontoparietal network (FPN) compared to that in typically developing individuals. The main purpose of the present study was to compare the within-network functional connectivity of the DMN, SN, FPN, and reading network in two groups of children with RLD: a group with lower-than-average working memory (LWM) and a group with average working memory (AWM). All subjects underwent resting-state functional magnetic resonance imaging (fMRI), and data were analyzed from a network perspective using the network brain statistics framework. The results showed that the LWM group had significantly weaker connectivity in a network that involved brain regions in the DMN, SN, and FPN than the AWM group. Although there was no significant difference between groups in reading network in the present study, other studies have shown relationship of the connectivity of the angular gyrus, supramarginal gyrus, and inferior parietal lobe with the phonological process of reading. The results suggest that although there are significant differences in functional connectivity in the associated networks between children with LWM and AWM, the distinctive cognitive profile has no specific effect on the reading network.

Two are better than one: Differences in cortical EEG patterns during auditory and visual verbal working memory processing between Unilateral and Bilateral Cochlear Implanted children

Despite the proven effectiveness of cochlear implant (CI) in the hearing restoration of deaf or hard-of-hearing (DHH) children, to date, extreme variability in verbal working memory (VWM) abilities is observed in both unilateral and bilateral CI user children (CIs). Although clinical experience has long observed deficits in this fundamental executive function in CIs, the cause to date is still unknown. Here, we have set out to investigate differences in brain functioning regarding the impact of monaural and binaural listening in CIs compared with normal hearing (NH) peers during a three-level difficulty n-back task undertaken in two sensory modalities (auditory and visual). The objective of this pioneering study was to identify electroencephalographic (EEG) marker pattern differences in visual and auditory VWM performances in CIs compared to NH peers and possible differences between unilateral cochlear implant (UCI) and bilateral cochlear implant (BCI) users. The main results revealed differences in theta and gamma EEG bands. Compared with hearing controls and BCIs, UCIs showed hypoactivation of theta in the frontal area during the most complex condition of the auditory task and a correlation of the same activation with VWM performance. Hypoactivation in theta was also observed, again for UCIs, in the left hemisphere when compared to BCIs and in the gamma band in UCIs compared to both BCIs and NHs. For the latter two, a correlation was found between left hemispheric gamma oscillation and performance in the audio task. These findings, discussed in the light of recent research, suggest that unilateral CI is deficient in supporting auditory VWM in DHH. At the same time, bilateral CI would allow the DHH child to approach the VWM benchmark for NH children. The present study suggests the possible effectiveness of EEG in supporting, through a targeted approach, the diagnosis and rehabilitation of VWM in DHH children.

Effectiveness of Computerized Cognitive Training on Working Memory in Pediatric Cancer Survivors: A Systematic Review and Meta-analysis

BACKGROUND

Interactive features of computerized cognitive training (CCT) may enhance adherence to training, providing a relatively low-cost intervention. A robust systematic review on the effectiveness of CCT for improving working memory (WM) among pediatric survivors with cancer is lacking.

OBJECTIVE

To summarize the available evidence and determine the effectiveness of CCT for WM among pediatric survivors with cancer.

INTERVENTIONS/METHODS

Five databases were searched. The Effective Public Health Practice Project was used to assess the study quality. ReviewerManager was used. The primary outcome was WM performance. Secondary outcomes included processing speed, attention, intervention adherence, and number of adverse events.

RESULTS

Six studies were included. Regarding overall quality, 1 study was weak, and 5 studies were moderate. Five studies reported a significant improvement of WM postintervention (P < .05). The meta-analysis of Cogmed interventions on symbolic WM revealed a significant difference between groups (vs placebo), with an overall pooled effect size of 0.71 (95% confidence interval, 0.02-1.41; P = .04). Two and 4 studies investigated the effects of CCT on processing speed and attention, respectively, with conflicting results. Four studies reported adherence of 80% or greater. Two studies reported no adverse events.

CONCLUSIONS

Computerized cognitive training using Cogmed has a significant positive effect on WM. The effects of CCT on processing speed and attention remain inconclusive.

IMPLICATIONS FOR PRACTICE

More rigorous trials should be conducted to elucidate the cognitive effects of CCT, particularly processing speed and attention, in the pediatric population with cancer. Further studies should consider combining CCT with other existing interventions to strengthen their effectiveness.

Cognitive-Motor Training Improves Reading-Related Executive Functions: A Randomized Clinical Trial Study in Dyslexia

Children with developmental dyslexia (DD) often struggle with executive function difficulties which can continue into adulthood if not addressed. This double-blinded randomized clinical trial study evaluated the short-term effects of the Verbal Working Memory-Balance (VWM-B) program on reading-related executive functions, reading skills, and reading comprehension in Persian children with DD. The active control group [12 children with DD with a mean age of 9 years (SD = 0.90)] received training using the single-task VWM program, while the experiment group [15 children with DD with a mean age of 8 years (SD = 0.74)] received training with the dual-task VWM-B program. Both groups received fifteen training sessions, and assessments were conducted before and after the intervention. The groups were homogenized for possible confounders of age, gender, IQ level, and attention level. The study employed separate mixed ANOVA analyses to estimate the impact of training programs on various measured functions. Significant improvements were observed in the outcome measures of backward digit span, text comprehension, verbal fluency, Stroop color-word test and interference, and the reading subtests. Additionally, significant correlations were found between reading skills and backward digit span, text comprehension, verbal fluency, and Stroop variables. In conclusion, the dual-task VWM-B program was found to be more effective than the single-task VWM program in improving selective attention, cognitive inhibition, verbal working memory capacity, information processing speed, naming ability, and lexical access speed. These enhanced executive functions were associated with improved reading skills in children with DD.

Cognitive Predictors of the Overlap of Reading and Math in Middle School

Math and reading skills are known to be related, and predictors of each are well researched. What is less understood is the extent to which these predictors, uniquely and collectively, overlap with one another, are differentially important for different academic skills, and account for the overlap of math and reading. We examined 20 potential predictors from four domains (working memory, processing speed, attention, and language) using latent variables and both timed and untimed achievement skill, in a sample (N=212) of at-risk middle schoolers, half of whom were English learners. The predictors accounted for about half of the overlap among achievement skills, suggesting that other factors (e.g., domain specific skills) might also be relevant for the overlap. We also found some differential prediction (language for reading, working memory for math). The present results extend and refine our understanding of the contribution of these cognitive predictors for reading and math.

Processing Speed Deficit and Its Relationship with Math Fluency in Children with Attention-Deficit/Hyperactivity Disorder

OBJECTIVES

(1) To determine the processing speed (PS) deficit in children with ADHD; and (2) To investigate if PS deficit was the primary cause of daily dysfunction in ADHD by testing the direct and indirect effects via working memory (WM) of PS on math fluency (MF).

METHOD

Seventy-eight children (52 children with ADHD and 26 controls) were tested on their motor, perceptual, cognitive, and verbal PS, WM, and MF.

RESULTS

Children with ADHD performed worse than controls on all PS, suggesting a general PS deficit. Moreover, cognitive PS was a significant predictor for MF. Mediation analysis showed that cognitive PS had direct and indirect effects via WM on MF, suggesting PS deficit might be the primary cause of MF difficulties in ADHD.

CONCLUSION

Findings of this study suggested a general PS deficit in ADHD. Due to the importance of PS in MF, interventions for MF underachievers should include assessment and training of PS.

Heterogeneity of short-term memory deficits in children with dyslexia

Many studies have highlighted short-term memory (STM) impairment in dyslexic individuals. Several studies showed deficits for both item and serial order aspects of verbal STM in dyslexic individuals. These group-based studies, however, do not inform us about the prevalence of these deficits and, importantly, their potential heterogeneity at the individual level. The present study examined both group-level and individual STM profiles in dyslexic and age-matched non-dyslexic children. While confirming previous group-based results of both item and serial order STM deficits, individual analyses indicated two distinct profiles: one profile was associated with verbal item STM and phonological impairment while another profile showed selective serial STM deficits in both verbal and visual domains. Our results highlight the need for practitioners to consider the heterogeneous nature of STM impairment in dyslexia and to adapt STM and reading treatment strategies accordingly.

Verbal Working Memory-Balance program training alters the left fusiform gyrus resting-state functional connectivity: A randomized clinical trial study on children with dyslexia

Sufficient activation of the left fusiform gyrus is important in reading ability acquisition due to its role in reading and naming, working memory (WM), and balance tasks. Recently, a newly-designed training program, Verbal Working Memory-Balance (VWM-B), has been evaluated on children with dyslexia, and its positive effects were shown on reading ability, WM capacity, and postural control. In the present study, we aimed to estimate the functional connectivity alterations of the left fusiform gyrus following training by the VWM-B. Before and after 15 sessions of training, the fMRI and other tools data were collected on a sample of children with dyslexia, who were allocated into two control and experiment groups. Data analyses showed the increased functional connectivity of the left fusiform gyrus between the left anterior temporal fusiform cortex, left and right Crus II regions of the cerebellum, and the left middle frontal gyrus. Moreover, VWM-B training significantly improved the reading and naming ability, WM capacity, and postural control of participants in the experiment group in comparison to the control. The current study findings emphasize the critical role of the left fusiform gyrus in reading ability. Moreover, it provides evidence to support the existence of cerebellar deficits in dyslexia.

The Role of Working Memory in Early Literacy and Numeracy Skills in Kindergarten and First Grade

The working memory system supports learning processes such as acquiring new information and the development of new skills. Working memory has been found to be related to both early literacy and early numeracy in kindergarten and to linguistic and mathematical academic skills at older ages, but the contribution of each of the memory components at these ages is not yet clear. The purpose of this study is to examine the unique connections among the various systems of WM, early literacy, and early numeracy using various assessment tests of simple WM and complex WM, as well as a variety of tasks in math and language skills administered to the same 250 children in kindergarten and 150 children in first grade. Consistent with the predictions, significant relations among all components of memory and mathematics and language knowledge at both ages were found, although these connections were differential for the different types of tasks and memory systems. The connection of complex WM was stronger in its contribution and more significant in first grade in both mathematics and language domains. Complex WM resources were more important in early literacy at kindergarten age, while simple WM seems to be important in early numeracy. The theoretical and educational implications of these results are discussed accordingly.

Semantic Priming and Its Link to Verbal Comprehension and Working Memory in Children with Learning Disorders

Children with learning disorders (LD children) often have heterogeneous cognitive impairments that affect their ability to learn and use basic academic skills. A proposed cause for this variability has been working memory (WM) capacity. Altered patterns of event-related potentials (ERPs) in these children have also been found in the N400 component associated with semantic priming. However, regarding the semantic priming effect in LD children, no distinction has been made for children with varying WM abilities. This study aims to explore the relationship of WM with the brain's electrophysiological response that underlies semantic priming in LD children that performed a lexical decision task. A total of 40 children (8-10 years old) participated: 28 children with LD and 12 age-matched controls. The ERPs were recorded for each group and analyzed with permutation-based t-tests. The N400 effect was observed only in the control group, and both groups showed a late positive complex (LPC). Permutation-based regression analyses were performed for the results from the LD group using the WISC-IV indices (e.g., Verbal Comprehension and WM) as independent predictors of the ERPs. The Verbal Comprehension Index, but not the WM index, was a significant predictor of the N400 and LPC effects in LD children.

White matter correlates of reading subskills in children with and without reading disability

Individual differences in reading ability are associated with characteristics of white matter microstructure in the brain. However, previous studies have largely measured reading as a single construct, resulting in difficulty characterizing the role of structural connectivity in discrete subskills of reading. The present study used diffusion tensor imaging to examine how white matter microstructure, measured by fractional anisotropy (FA), relates to individual differences in reading subskills in children aged 8 to 14 (n = 65). Findings showed positive correlations between FA of the left arcuate fasciculus and measures of single word reading and rapid naming abilities. Negative correlations were observed between FA of the right inferior longitudinal fasciculus and bilateral uncinate fasciculi, and reading subskills, particularly reading comprehension. The results suggest that although reading subskills rely to some extent on shared tracts, there are also distinct characteristics of white matter microstructure supporting different components of reading ability in children.

The cumulative effect of socioeconomic status and dyslexia on linguistic, cognitive and reading skills among Arabic-speaking children

Research has shown that children with dyslexia and children with a low socioeconomic status (SES) fall behind in terms of literacy acquisition, but a question remains regarding the cumulative effect of dyslexia and SES on linguistic, cognitive and reading skills. To examine the impact of cognition and environment on literacy development, we returned to the data set of 1,441 elementary school children (223 dyslexic readers and 1,241 typical readers) from low and medium-high SES backgrounds within Palestinian society in Israel who had participated in the development study of a comprehensive battery of tests in oral and written Arabic. The findings of this retrospective study reveal that, across grade levels, dyslexic readers from a low SES background showed similar performance to those from a medium-high SES background on most linguistic, cognitive and reading measures. As for typical readers, SES contributed to individual differences in all linguistic, cognitive and reading indices, with the exception of RAN. Finally, a cumulative effect of dyslexia and SES was found in relation to morphology, vocabulary, listening comprehension and text-reading accuracy.

Dichotic listening deficits in children with hearing loss

PURPOSE

This correlational study compared dichotic listening among children with significant hearing loss to typically developing children and children clinically assessed for auditory processing disorder.

METHOD

Recorded versions of two dichotic tests were delivered under earphones or in the sound field for children using amplification. Individual ear scores and interaural asymmetry were compared to normative data. Matched deficit patterns from both tests were identified, ranked for severity of deficit, and compared across groups. Relationships between dichotic scores and factors related to amplification were investigated in the children with hearing loss.

RESULTS

Dichotic scores were significantly poorer among children with hearing loss without the large interaural asymmetries seen in children assessed clinically for auditory processing problems. Device type and age of implantation had no effect on scores; non-dominant ear scores on the digits test were significantly correlated to age of device use in the left ear and duration of device use in the right ear. Non-dominant ear scores with digits were also significantly correlated with bilateral word recognition.

CONCLUSIONS

Poor dichotic perception in children with significant hearing losses may be related to the use of recorded test materials, immature skills in attention and working memory, or other factors that contribute to development of vocabulary and language. These weaknesses may interfere with successful mainstream educational placement in these children. Assessment of dichotic performance in this population could lead to deficit-specific interventions that may improve outcomes and enhance educational opportunities for children with hearing loss.

The association between working memory and mathematical problem solving: A three-level meta-analysis

Although working memory (WM) is an important factor in mathematical problem solving (MPS), it remains unclear how well WM relates to MPS. Thus, we aimed to determine this relationship by using a meta-analysis. We searched electronic databases for studies published between 2000 and 2020 and established operational criteria. We conducted Egger’s regression tests and created funnel plots to test for publication bias. Finally, a three-level meta-analytic model analysis of data from 130 studies involving 43,938 participants and 1,355 effect sizes revealed a moderate relationship between WM and MPS (r = 0.280, 95% CI = [0.263, 0.314]). Moreover, moderator analyses showed that: (1) dressed-up word problems were more strongly tied to WM than to intra-mathematical problems; (2) the central executive function showed the strongest relation with MPS, whereas the phonological loop had the weakest; (3) gender ratio had significant moderating effects; and (4) some of the above-mentioned significant moderating effects were unique after controlling for other factors. Implications for research and practice were also discussed.

Cognitive predictors of language abilities in primary school children: A cascaded developmental view

This study investigated the longitudinal relationship between children's domain-general cognitive constraints underlying phonological and sentence processing development in a big sample of typically developing children. 104 children were tested on non-linguistic processing speed, phonological skills (phonological short term memory, phonological knowledge, phonological working memory), and sentence processing abilities (sentence repetition and receptive grammar) in 1^st grade (aged 6 to 6.5) and one year later. A cross-lagged structural equation model showed that non-linguistic processing speed was a concurrent predictor of phonological skills, and that phonology had a powerful effect on the child's sentence processing abilities concurrently and longitudinally, providing clear evidence for the role of domain-general processes in the developmental pathway of language. These findings support a cascaded cognitive view of language development and pose important challenges for evaluation and intervention strategies in childhood.

Longitudinal relations between self-regulatory skills and mathematics achievement in early elementary school children from Chinese American immigrant families

Drawing from two waves (∼1.5-2.5 years apart) of longitudinal data, the current study investigated the bidirectional associations between self-regulatory skills and mathematics achievement among a socioeconomically diverse sample of school-age Chinese American children from immigrant families (N = 258; 48.1% girls; ages 5.8-9.1 years; first to third grades at Wave 1). Children's self-regulatory skills were assessed with task-based measures of attention focusing, inhibitory control, behavioral persistence, and comprehensive executive function as well as parent- and teacher-reported effortful control. Multiple regressions showed that behavioral persistence and parent-reported effortful control positively predicted math achievement over time. Math achievement positively predicted comprehensive executive function over time. These effects were found when controlling for child age, sex, generation status, family socioeconomic status, parents' cultural orientations, and prior levels of math achievement or self-regulation. The prospective relation of math achievement predicting comprehensive executive function remained significant after a false discovery rate correction.

Goal-directedness enhances letter-speech sound learning and consolidation in an unknown orthography

This study examined how top-down control influenced letter-speech sound (L-SS) learning, the initial phase of learning to read. In 2020, 107 Dutch children (53 boys, M_age  = 106.845 months) learned eight L-SS correspondences, either preceded by goal-directed or implicit instructions. Symbol knowledge and artificial word-reading ability were assessed immediately after learning and on the subsequent day to examine the effect of sleep. Goal-directed children were faster and more efficient in learning a new script and had better learning outcomes compared to children who were not instructed about the goal of the task. This study demonstrates that directing children toward the goal can promote L-SS learning and consolidation, giving insights into how top-down control influences the initial phase of reading acquisition.

Self-motivated and directed learning across the lifespan

Self-motivated and directed learning is integral to knowledge base expansion for learners of all ages. Both motivational and cognitive processes drive self-motivated and directed lifelong learning, yet how these different processes operate together from childhood through adulthood is largely unknown. In this review, we discuss the role of personal motivators, such as beliefs in self-efficacy and personality traits in self-motivated and directed learning across the lifespan. We then consider the role of cognitive processes that contribute to knowledge base expansion in learners of all ages, specifically executive functions. We focus on working memory, inhibitory control, and task switching as potential determinants of lifelong learning. Finally, we integrate the two literatures, to discuss ways in which personal motivators may influence deployment of executive functions under self-motivated and directed conditions as a learner advances along a developmental trajectory. We also suggest ways to move the study of self-motivated and directed learning beyond observation and self-report measures thus affording experimental control. We aim to provide a more comprehensive understanding and novel insight to the mechanisms and processes of self-motivated and directed learning across the lifespan.

The effect of backpack weight on the performance of basic short-term/working memory tasks while walking along a pre-determined route

This study investigated possible backpack weight effects on the performance of three basic short-term/working memory (STM/WM) tasks conducted concurrently with the physical task of route walking. The STM/WM tasks were the Corsi block-tapping, digit span, and 3-back tasks, and, were employed to examine the visuo-spatial sketchpad, phonological loop and central executive components of the WM system. Four backpack weight levels (0%, 15%, 25% and 40% of body mass) were considered. Thirty participants conducted the three experimental tasks requiring physical-cognitive multitasking. Data analyses revealed that: (1) increased backpack weight resulted in decreases in the performance of the Corsi block-tapping and the 3-back task, but (2) backpack weight did not significantly affect the digit span task performance. The study results suggest that reducing backpack weight could benefit the performance of various cognitive tasks during route walking. The study findings may be useful for the ergonomics design of body-worn equipment and human-system interfaces.Practitioner summary: This study examined the backpack weight effects on the performance of three basic short-term/working memory tasks conducted concurrently with the physical task of route walking. The study revealed that reducing backpack weight could benefit various cognitive tasks during physical-cognitive multitasking, especially cognitive tasks that require visuospatial processing and executive control.

Speech-Language Pathology Interventions for Children With Executive Function Deficits: A Systematic Literature Review

PURPOSE

The purpose of this synthesis was to systematically review the research and guidance for school-based speech-language pathologists (SLPs) who provide intervention to children with developmental executive function (EF) deficits, particularly those children with co-occurring developmental language disorder (DLD).

METHOD

We conducted a structured search of four major electronic databases, as well as a manual review of references and journals, which yielded 4,571 nonduplicate articles. We screened first titles and abstracts and then full texts to identify peer-reviewed articles, dissertations, and theses containing research or guidance for SLPs' interventions for children with co-occurring DLD and EF deficits; this process yielded 27 articles for analysis. We categorized these studies by type of publication and synthesized their contents to assess the evidence base for EF interventions in children with DLD and to evaluate the guidance for SLP-implemented direct and indirect interventions.

RESULTS

A small body of research explores the efficacy of SLPs' intervention for children with co-occurring DLD and EF deficits, generally finding modest but inconsistent effects of cognitive interventions and strategy training to improve language outcomes. Meanwhile, nonempirical articles (e.g., tutorials) offer guidance to SLPs to support students with EF deficits through direct and indirect services.

CONCLUSIONS

A growing body of literature equips SLPs with the principles and strategies of EF intervention. Many of these articles are sourced from literature about children with EF deficits or attention-deficit/hyperactivity disorder, but few empirical studies measure the efficacy of these interventions for children with co-occurring DLD.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.21401901.

Explore versus store: Children strategically trade off reliance on exploration versus working memory during a complex task

During complex tasks, we use working memory to actively maintain goal sets and direct attention toward goal-relevant information in the environment. However, working memory is severely limited, and storing information in working memory is cognitively effortful. Previous work by Kibbe and Kowler [2011, Journal of Vision, 11(3), Article 14] showed that adults strategically modulate reliance on working memory during complex, goal-oriented tasks, varying the amount of information they store in working memory depending both on the cognitive demands of the task and on the ease with which task-relevant information can be accessed from the environment. We asked whether children, whose working memory and executive functions are undergoing significant developmental change, also use working memory strategically during complex tasks. Forty-six 8-10-year-old children searched through arrays of hidden objects to find three that belonged to a given category defined over the objects' features. We manipulated the cognitive demands of the task by increasing the complexity of the category. We manipulated the exploration costs of the task by varying the rate at which task-relevant information could be accessed. We measured children's search patterns to gain insights into how the children used working memory during the task. We found that as the cognitive demands of the task increased, children stored less information in working memory, relying more on exploration. When exploration was costlier, children explored less, storing more in working memory. These results suggest that developing children, like adults, make strategic decisions about when to explore versus when to store during a complex, goal-oriented task.

Working memory span and receptive vocabulary assessment in Urdu speaking children with speech sound disorder

Emerging evidence suggests that impaired speech may be related to reduced working memory (WM). The current study aimed to validate and compare the influence of articulation, short-term memory (STM), WM, and receptive vocabulary abilities of Pakistani children with speech sound disorder (SSD; N = 50) versus typically developing (TD; N = 30) children aged 7-13 years. Assessments included the Test for Assessment of Articulation and Phonology in Urdu (TAAPU), Peabody Picture Vocabulary Test-4, translated to Urdu (U-PPVT-4), and Digit Memory Test (DMT) used to determine speech articulation, receptive vocabulary, and memory abilities respectively. The percentage correct consonants (PCC) score was used to divide the SSD group further into SSD severity groups. The TD and SSD groups significantly differed in performance on all tasks (p < 0.05). Moreover, the SSD severity groups showed significant differences (p < 0.0001) in performance on different components of TAAPU (total errors and substitution errors) and DMT tasks. However, the SSD severity groups did not show significant differences in performance on the U-PPVT-4. Correlational analyses indicate statistically significant correlations of PCC with STM, WM, and receptive vocabulary. Regression analyses suggested that both WM and STM contribute to speech intelligibility in children with SSD. Our findings in Urdu-speaking children support previous results in English-speaking children suggesting the articulation skills, receptive vocabulary, STM, and WM were less developed in children with SSD than in TD children.

Executive functions as mediators between socioeconomic status and academic performance in Chinese school-aged children☆

Background

It is well-documented that socioeconomic status (SES) and academic performance in school-aged children are closely related. However, little is known about how the three core executive functions (EFs), inhibition, working memory, and cognitive flexibility, mediate the association between the two. Moreover, most previous studies examined SES disparities in Western countries, how such disparities in EF and academic performance manifest in the Chinese context, where a distinctive EF profile and learning experience are observed, remains uncertain. The current study explored: (1) the mediating effects of the three core EFs in the association between SES and academic performance; and (2) the differences in EF and academic performance in three core subjects between Chinese children who are below and above the poverty line.

Methods

Of the 385 students sampled, 205 are in the low-SES group and 180 are in the middle-high SES group.

Results

A structural equation model showed that the SES-academic performance relationship was fully mediated by cognitive flexibility and working memory but not inhibition. Working memory was a much stronger mediator than cognitive flexibility, suggesting that working memory may correlate with childhood SES and academic performance in Chinese children. An analysis of covariance suggested that compared to the middle-high SES group, the low-SES group demonstrated poorer working memory and academic performance in all three subjects after controlling for age and IQ. Interestingly, children with low-SES were found to have better cognitive flexibility than children with middle-high SES.

Conclusions

These findings suggest that interventions targeting working memory may be an important area to improve children's academic performance.

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This study examined (1) the mediating effects of executive function in the association between socioeconomic status and academic performance; and (2) the differences in executive function and academic performance in three core subjects between Chinese children who are below and above the poverty line.

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Both socioeconomic status groups exhibited differences in cognitive flexibility, working memory, and academic performance in all three core subjects.

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The socioeconomic status-achievement relationship was mediated by cognitive flexibility and working memory but not inhibition. Working memory was a stronger mediator than cognitive flexibility in explaining academic performance.

Effects of a short and intensive transcranial direct current stimulation treatment in children and adolescents with developmental dyslexia: A crossover clinical trial

Developmental Dyslexia (DD) significantly interferes with children’s academic, personal, social, and emotional functioning. Nevertheless, therapeutic options need to be further validated and tested in randomized controlled clinical trials. The use of transcranial direct current stimulation (tDCS) has been gaining ground in recent years as a new intervention option for DD. However, there are still open questions regarding the most suitable tDCS protocol for young people with DD. The current crossover study tested the effectiveness of a short and intensive tDCS protocol, including the long-term effects, as well as the influence of age and neuropsychological processes at baseline on reading improvements. Twenty-four children and adolescents with DD were randomly assigned to receive active tDCS during the first slot and sham tDCS during the second slot or vice versa. Five consecutive daily sessions of left anodal/right cathodal tDCS set at 1 mA for 20 min were administered over the parieto-occipital regions. Reading measures (text, high frequency word, low frequency word, and non-word lists) and neuropsychological measures (visual-spatial and verbal working memory, phoneme blending, and rapid automatized naming tasks) were collected before, immediately after, 1 week and 1 month later the treatment. Our results showed that only the active tDCS condition improved non-word reading speed immediately after and 1 month later the end of the treatment compared with baseline. In addition, the improvement in non-word reading speed was significantly correlated with age and with neuropsychological measures (verbal working memory and phoneme blending) at baseline but only in the active tDCS condition. The current crossover study contributed to enforce previous effects of tDCS, including long-term effects, on non-word reading speed and to understand the effect of age and neuropsychological processes on reading outcomes. Our findings showed that tDCS could be a low-cost and easy-to-implement treatment option with long-term effects for children and adolescents with DD.

When (deliberate) practice is not enough – the role of intelligence, practice, and knowledge in academic performance

It is well established that academic performance (AP) depends on a number of factors, such as intellectual capacities, practice, and previous knowledge. We know little about how these factors interact as they are rarely measured simultaneously. Here we present mediated-Factors of Academic Performance (m-FAP) model, which simultaneously assesses direct and indirect, mediated, effects on AP. In a semester-long study with 118 first-year college students, we show that intelligence and working memory only indirectly influenced AP on a familiar, less challenging college course (Introduction to Psychology). Their influence was mediated through previous knowledge and self-regulated learning activities akin to deliberate practice. In a novel and more challenging course (Statistics in Psychology), intellectual capacities influenced performance both directly and indirectly through previous knowledge. The influence of deliberate practice, however, was considerably weaker in the novel course. The amount of time and effort that the students spent on the more difficult course could not offset the advantage of their more intelligent and more knowledgeable peers. The m–FAP model explains previous contradictory results by providing a framework for understanding the extent and limitations of individual factors in AP, which depend not only on each other, but also on the learning context.

Developmental Dyslexia: Disorder or Specialization in Exploration?

We raise the new possibility that people diagnosed with developmental dyslexia (DD) are specialized in explorative cognitive search, and rather than having a neurocognitive disorder, play an essential role in human adaptation. Most DD research has studied educational difficulties, with theories framing differences in neurocognitive processes as deficits. However, people with DD are also often proposed to have certain strengths - particularly in realms like discovery, invention, and creativity - that deficit-centered theories cannot explain. We investigate whether these strengths reflect an underlying explorative specialization. We re-examine experimental studies in psychology and neuroscience using the framework of cognitive search, whereby many psychological processes involve a trade-off between exploration and exploitation. We report evidence of an explorative bias in DD-associated cognitive strategies. High DD prevalence and an attendant explorative bias across multiple areas of cognition suggest the existence of explorative specialization. An evolutionary perspective explains the combination of findings and challenges the view that individuals with DD have a disorder. In cooperating groups, individual specialization is favored when features that confer fitness benefits are functionally incompatible. Evidence for search specialization suggests that, as with some other social organisms, humans mediate the exploration-exploitation trade-off by specializing in complementary strategies. The existence of a system of collective cognitive search that emerges through collaboration would help to explain our species' exceptional adaptiveness. It also aligns with evidence for substantial variability during our evolutionary history and the notion that humans are adapted not to a particular habitat but to variability itself. Specialization creates interdependence and necessitates balancing complementary strategies. Reframing DD therefore underscores the urgency of changing certain cultural practices to ensure we do not inhibit adaptation. Key improvements would remove cultural barriers to exploration and nurture explorative learning in education, academia, and the workplace, as well as emphasize collaboration over competition. Specialization in complementary search abilities represents a meta-adaptation; through collaboration, this likely enables human groups (as a species and as cultural systems) to successfully adapt. Cultural change to support this system of collaborative search may therefore be essential in confronting the challenges humanity now faces.

A Neuropsychological Profile of Developmental Dyscalculia: The Role of Comorbidity

Developmental dyscalculia (DD) has long been thought to be determined by multiple components. Dyscalculia has high comorbidity with other learning and developmental disabilities, including reading and writing disorders, attention deficits, and problems in visual/spatial skills, short memory, and working memory. This study aims to assess prevalence rates for isolated as well as comorbid DD in a sample of Italian-speaking children. In addition, we studied the neuropsychological profile of children with isolated or combined dyscalculia. We tested 380 children (176 males and 204 females) between the ages of 8.17 and 9.33 years using an extensive battery to determine the neuropsychological profile. The assessment included an arithmetic battery and nonverbal intelligence, short-term memory, reading, and writing tests. The results indicated that children with DD more frequently have a reading disorder and writing disorder. They also have a lower nonverbal intelligence quotient (IQ) and obtain significantly lower scores in short-term memory tests and on a visuospatial skills questionnaire. They also had significantly higher scores (indicative of greater attentional difficulties) in the Conners subscale for attentional problems. Children with DD present different cognitive and neuropsychological profiles.

Children's Involvement in Different Sport Types Differentiates Their Motor Competence but Not Their Executive Functions

Sports provide a context where important aspects of children’s health, such as motor skills and cognitive functions, can be enhanced. However, it is unknown which type of sport may be better for the development of motor competence (MC) and executive functions (EFs). This study investigated potential differences in MC and EFs in boys and girls, being involved in different types of sports (team, individual open skill, individual closed skill). A total of 115 children (49 boys), 8–12 years old (10.30 ± 1.19 years), participated in the study. Their MC was assessed with the Bruininks–Oseretsky Test of Motor Proficiency-2 Short Form, whereas for EFs, the Attention Network Test, the digits backwards test, and the how many–what number test were utilized. Significant MC differences among participants in different types of sports were revealed, favoring those from closed-skill sports; nevertheless, their EFs were at similar levels. Furthermore, no significant gender MC and EFs differences were detected. It seems that children’s participation in specific types of sports differentiates their motor skills but not their EFs, whereas boys and girls, when provided with the same opportunities, present similar levels of MC and EFs.

The relationship between cognitive control and lexical conflict resolution in developmental dyslexia

Previous studies have revealed that cognitive control functions contribute to the resolution of lexical interference. Both cognitive control (CC) deficits and reduced speed of lexical retrieval in Rapid Automatized Naming (RAN) tasks are characteristics of Developmental Dyslexia (DD), but it is still not fully understood how these deficits relate to each other and to reading problems. To examine this question, we tested adolescents with DD (n = 38), poor readers (PR; n = 25) and typical readers (TR; n = 33) matched on age and IQ, on CC functions with Stroop, Stop Signal, Simon, Backward Digit Span and n-back tasks and on lexical retrieval and lexical conflict resolution with RAN of pictures in semantically homogeneous vs. mixed trials. As expected, in the blocked RAN Task DD individuals showed longer naming times and a greater effect of lexical conflict resolution (indexed by difference scores of naming times in the homogeneous and mixed conditions) than TR participants. We also found significant group differences (TR = PR > DD) in CC measures. Naming time was associated with CC, while the lexical interference effect did not show any association with this set of abilities. These findings suggest that DD individuals show impairments in multiple cognitive functions, such as cognitive control, lexical retrieval and lexical conflict resolution. Our results also suggest that CC functions are involved in lexical retrieval, but we have not found evidence for their involvement in lexical conflict resolution processes.

Reading impairment in adolescents with fetal alcohol spectrum disorders

PURPOSE

To date, research on effects of prenatal alcohol exposure (PAE) has focused on a broad range of cognitive impairments, but relatively few studies have examined effects of PAE on development of reading skills. Although PAE has been linked to poorer reading comprehension, it remains unclear whether this impairment is attributable to deficits in phonological processing, word reading, oral language skills, and/or executive functioning.

METHODS

A comprehensive reading battery was administered to 10 adolescents with fetal alcohol syndrome (FAS); 16 with partial FAS; 30 nonsyndromal heavily-exposed; 49 controls.

RESULTS

PAE was related to poorer reading comprehension but not to single word reading or phonological processing, suggesting that the mechanics of reading are intact in adolescents with fetal alcohol spectrum disorders at this age. PAE-related impairment in reading comprehension was mediated, in part, by deficits in mastery of oral language skills, including vocabulary, language structure, and verbal fluency.

CONCLUSIONS

These results are consistent with research showing that reading comprehension in adolescence relies increasingly on linguistic comprehension abilities, especially once word reading becomes automatic and text complexity increases. Our findings suggest that reading-impaired adolescents with PAE will benefit from intervention programs targeting vocabulary knowledge, language structure, verbal fluency, and reading comprehension skills.

Effects of Working Memory Training on Children’s Memory and Academic Performance: the Role of Training Task Features and Trainee’s Characteristics

Learning and academic performance are explained mainly by basic limited-capacity processes, most notably by working memory (WM). Consequently, training WM has been considered a promising approach to fostering these abilities. However, school-based investigations are rare. This study examined the effects of training task features and trainees’ characteristics on transfer to cognitive and academic measures. Eighty-six typically developing 8–12-year-old children completed 6 weeks of either WM training with n-back and complex span tasks or a control training with perceptual-matching tasks in a regular school setting. The study also assessed some personal variables of the children, such as neuroticism, conscientiousness, joy of learning, and power of endurance. The WM training group showed increased WM and math performance compared to the control group. Also, there was a trend toward some improvements in vocabulary after WM training, and overall improvements after both trainings were observed in fluid intelligence and reading. Analyses of individual differences in the WM training group indicated increased training performance in relation to emotional stability, conscientiousness, power of endurance, as well as teacher-reported joy of learning and social integration of participants. Thus, the results indicate the potential of WM training to improve WM capacity and mathematical skills and reveal the impact of regulative, motivational, and social factors on cognitive training performance.

Rapid auditory processing and medial geniculate nucleus anomalies in Kiaa0319 knockout mice

Developmental dyslexia is a common neurodevelopmental disorder characterized by difficulties in reading and writing. Although underlying biological and genetic mechanisms remain unclear, anomalies in phonological processing and auditory processing have been associated with dyslexia. Several candidate risk genes have also been identified, with KIAA0319 as a main candidate. Animal models targeting the rodent homolog (Kiaa0319) have been used to explore putative behavioral and anatomic anomalies, with mixed results. For example after downregulation of Kiaa0319 expression in rats via shRNA, significant adult rapid auditory processing impairments were reported, along with cortical anomalies reflecting atypical neuronal migration. Conversely, Kiaa0319 knockout (KO) mice were reported to have typical adult auditory processing, and no visible cortical anomalies. To address these inconsistencies, we tested Kiaa0319 KO mice on auditory processing tasks similar to those used previously in rat shRNA knockdown studies. Subsequent neuroanatomic analyses on these same mice targeted medial geniculate nucleus (MGN), a receptive communication-related brain structure. Results confirm that Kiaa0319 KO mice exhibit significant auditory processing impairments specific to rapid/brief stimuli, and also show significant volumetric reductions and a shift toward fewer large and smaller neurons in the MGN. The latter finding is consistent with post mortem MGN data from human dyslexic brains. Combined evidence supports a role for KIAA0319 in the development of auditory CNS pathways subserving rapid auditory processing functions critical to the development of speech processing, language, and ultimately reading. Results affirm KIAA0319 variation as a possible risk factor for dyslexia specifically via anomalies in central acoustic processing pathways.

What components of working memory are associated with children's reading skills?

Working memory (WM) is a potentially important factor related to the development of and performance in reading skills. This study examined the differential relations between two components of the WM system (i.e., storage, processing) and reading. Latent variables were created based on data from 1900 children (1146 children in preschool-second grade and 754 children in third-fifth grade) recruited for a larger study concerning the development of reading comprehension. Results indicated that a general-specific model of WM was a good fit to the data and effectively isolated the variance unique to WM-processing from that of WM-storage. Using the general-specific model, relations between the components of WM and reading (e.g., reading comprehension, decoding) and reading-related (e.g., oral language, phonological awareness, nonverbal IQ) outcomes were examined. In contrast with previous studies that have suggested WM is consistently associated with reading comprehension, our findings indicate that both aspects of WM (i.e., storage, processing) operate primarily indirectly through foundational reading-related skills. In sum, the WM system is not specifically associated with reading comprehension as most of the effects of WM-processing are indirect via the effects on foundational reading-related skills.

Increased cortisol levels caused by acute resistance physical exercise impair memory and learning ability

Acute physical exercise works as an activator of the responses of the human organism to stress. This is based on the activation of the hypothalamic-pituitary-adrenal (HPA) axis, affecting physical, physiological and psychological levels. This study aimed to analyse the effects of a single bout of high-intensity resistance exercise on cognitive-behavioural responses: visuo-spatial path learning and memory, as well as physiological responses (salivary cortisol levels). Nineteen healthy male military-trained powerlifting subjects were tested in a within-subject design on two experimental days with an interval of 48 h. The stress and cognitive variables were measured by cortisol levels and Ruff-Light trail-learning test (RULIT) test scores, respectively. The results showed the immediate influence of acute exercise on cortisol, with significantly higher cortisol levels found in subjects after completion of the acute resistance exercise. In addition, this study found a significant deterioration of memory and learning ability after a dose of intense resistance exercise. In conclusion, the study highlights the relative effects of resistance exercise on cortisol and cognitive performance depending on the intensity and type of the exercise, the moment of measurement and the cerebral areas implicated.

An Investigation of Working Memory Profile and Fluid Intelligence in Children With Neurodevelopmental Difficulties

The present study aims to evaluate the distinct patterns of working memory (WM) capacity of children with Developmental Language Disorder (DLD), High-functioning children with Autism Spectrum Disorder (ASD) and children with Down syndrome (DS). More specifically, the current study investigates the complex relationship of fluid intelligence and WM between 39 children with DLD, 20 H igh-functioning children with ASD, and 15 children with DS. All children were evaluated in different measures of Phonological Working Memory, Visual-spatial Working Memory whereas Fluid Intelligence was measured with Raven Progressive Matrices. The result analysis revealed a significant difference among the three groups, both among each function separately and the correlations among them, as well. The results revealed that the DLD groups and High-functioning ASD group exhibited a common picture or an overlap of performances in all Phonological and Visuo-spatial working memory measures, except Backward Digit Recall task. As for the DS group research findings revealed different and unique working memory patterns in comparison to DLD group and High-functioning ASD. Their differences have been studied and further conclusions have been drawn about the different patterns of working memory among the three clinical groups. The implications of these findings are discussed in light of support for learning. The common profile that characterize the two developmental conditions and the distinct pattern of working memory performance in DS group underlies the need for further research in the field.

Use of Parsing Heuristics in the Comprehension of Passive Sentences: Evidence from Dyslexia and Individual Differences

This study examined the comprehension of passive sentences in order to investigate whether individuals with dyslexia rely on parsing heuristics in language comprehension to a greater extent than non-dyslexic readers. One hundred adults (50 dyslexics and 50 controls) read active and passive sentences, and we also manipulated semantic plausibility. Eye movements were monitored, while participants read each sentence, and afterwards, participants answered a comprehension question. We also assessed verbal intelligence and working memory in all participants. Results showed dyslexia status interacted with sentence structure and plausibility, such that participants with dyslexia showed significantly more comprehension errors with passive and implausible sentence. With respect to verbal intelligence and working memory, we found that individuals with lower verbal intelligence were overall more likely to make comprehension errors, and individuals with lower working memory showed particular difficulties with passive and implausible sentences. For reading times, we found that individuals with dyslexia were overall slower readers. These findings suggest that (1) individuals with dyslexia do rely on heuristics to a greater extent than do non-dyslexic individuals, and (2) individual differences variables (e.g., verbal intelligence and working memory) are also related to the use of parsing heuristics. For the latter, lower ability individuals tended to be more consistent with heuristic processing (i.e., good-enough representations).

Neurophysiological Verbal Working Memory Patterns in Children: Searching for a Benchmark of Modality Differences in Audio/Video Stimuli Processing

Exploration of specific brain areas involved in verbal working memory (VWM) is a powerful but not widely used tool for the study of different sensory modalities, especially in children. In this study, for the first time, we used electroencephalography (EEG) to investigate neurophysiological similarities and differences in response to the same verbal stimuli, expressed in the auditory and visual modality during the n-back task with varying memory load in children. Since VWM plays an important role in learning ability, we wanted to investigate whether children elaborated the verbal input from auditory and visual stimuli through the same neural patterns and if performance varies depending on the sensory modality. Performance in terms of reaction times was better in visual than auditory modality (p = 0.008) and worse as memory load increased regardless of the modality (p < 0.001). EEG activation was proportionally influenced by task level and was evidenced in theta band over the prefrontal cortex (p = 0.021), along the midline (p = 0.003), and on the left hemisphere (p = 0.003). Differences in the effects of the two modalities were seen only in gamma band in the parietal cortices (p = 0.009). The values of a brainwave-based engagement index, innovatively used here to test children in a dual-modality VWM paradigm, varied depending on n-back task level (p = 0.001) and negatively correlated (p = 0.002) with performance, suggesting its computational effectiveness in detecting changes in mental state during memory tasks involving children. Overall, our findings suggest that auditory and visual VWM involved the same brain cortical areas (frontal, parietal, occipital, and midline) and that the significant differences in cortical activation in theta band were more related to memory load than sensory modality, suggesting that VWM function in the child's brain involves a cross-modal processing pattern.

Effects of Teaching Presentation Methods and Visual and Auditory Working Memory Capacity on Young Children’s Learning Effectiveness

Objectives: This study investigates the effects of teaching material presentation methods and young children's visual and auditory working memory capacity on their learning effectiveness. It also suggests effective instructional design and teaching-learning methods suitable for children’s information processing characteristics.Methods: Participants included 86 five-year-old children enrolled in kindergartens in Seoul, Gyeonggi, Incheon, and Daejeon. Three categories of teaching materials with different presentation methods were created. Participants were randomly assigned to one of the category groups, and participated in learning activities. After the activities, learning effectiveness, working memory, and attention were measured. Data were analyzed using SPSS 20.0.Results: Results indicated that children’s learning effectiveness differed according to the teaching material presentation method. Higher learning effectiveness was observed when auditory and visual information was presented concurrently rather than sequentially, but learning was not affected by the sequential order. The groups with larger auditory working memory capacity and larger visual working memory capacity achieved higher learning effectiveness than did their respective counterparts. Additionally, learning effectiveness was greater for children with larger auditory working memory capacity when presented with auditory information before visual, and for those with larger visual working memory capacity when presented with visual information before auditory.Conclusion: The study results enhance foundational knowledge related to individual differences in young children's visual and auditory information processing abilities. Moreover, this study has practical implications for developing instructional materials and proposals suitable for young children’s individual information processing characteristics.

Framing the area: An efficient approach for avoiding visual interference and optimising visual search in adolescents

Attentional resources are limited, and resistance to interference plays a critical role during cognitive tasks and learning. Previous studies have shown that participants find it difficult to avoid being distracted by global visual information when processing local details. In this study, we investigated an innovative approach for enhancing the processing of local visual details by middle-school adolescents. Two groups completed a classic global/local visual search task in which a predefined target could appear at the global or local level, either with or without a frame. The results from the no-frame display group provided a direct replication in adolescents of previous findings in adults, with increasing number of interferent stimuli presented in the display adversely affecting detection of local targets. In addition, by varying the numbers of distractors inside and outside the frame, we showed that distractors only interfered with the processing of local information inside the frame, while the deleterious impact of increases in distracting information was prevented when the distractors were outside the frame. These findings suggest that when a frame delimits an attentional area, the influence of an increasing number of distractors present outside the frame is eliminated. We assume that application of a frame allows for efficient delimitation of attention deployment to a restricted topographical visual area in adolescents. These results evidence that processing of local details can be improved without modifying the structure of the stimuli, and provide promising clues for optimising attentional resources during time-absorbing visual searches. Applicable implications in the educational field are discussed.

On the Working Memory of Humans and Great Apes: Strikingly Similar or Remarkably Different?

In this article we review publications relevant to addressing widely reported claims in both the academic and popular press that chimpanzees working memory (WM) is comparable to, if not exceeding, that of humans. WM is a complex multidimensional construct with strong parallels in humans to prefrontal cortex and cognitive development. These parallels occur in chimpanzees, but to a lesser degree. We review empirical evidence and conclude that the size of WM in chimpanzees is 2 ± 1 versus Miller's famous 7 ± 2 in humans. Comparable differences occur in experiments on chimpanzees relating to strategic and attentional WM subsystems. Regardless of the domain, chimpanzee WM performance is comparable to that of humans around the age of 4 or 5. Next, we review evidence showing parallels among the evolution of WM capacity in hominins ancestral to Homo sapiens, the phylogenetic evolution of hominins leading to Homo sapiens, and evolution in the complexity of stone tool technology over this time period.

The relationship between cognition and mathematics in children with attention-deficit/hyperactivity disorder: a systematic review

Cognitive processes play an imperative role in children's mathematics learning. Difficulties in cognitive functioning are a core feature of Attention Deficit Hyperactivity Disorder (ADHD) in children, who also tend to show lower levels of mathematics attainment than their typically developing peers. This review (registration number: CRD42020169708) sought to aggregate findings from studies assessing the relationship between cognition and mathematics in children with a clinical ADHD diagnosis aged 4-12 years. A total of 11,799 studies published between 1992 and August 2020 were screened for eligibility using various database (PsycINFO, PubMed, SCOPUS, EMBASE, ERIC, Web of Science, and additional sources), from which four studies met inclusion criteria. A narrative synthesis was conducted on the correlations between mathematics and cognitive domains, including an evaluation of the risk of bias within the studies. Across four studies meeting inclusion criteria, memory, inhibitory control, and processing speed were assessed. The results showed a positive association between cognition and mathematics performance in this population. The strength of associations across these studies varied as a function of the cognitive domain in question, means by which mathematics performance was assessed, as well as whether confounding factors such as age and IQ were controlled for. Collectively, this review demonstrates a lack of research in this area and points to various methodological considerations for identifying the association between cognition and mathematics performance in ADHD.

Factors that influence non-word repetition performance in children with and without persistent speech sound disorders

BACKGROUND

Nonword repetition (NWR) is a common phonological processing task that is reported to tap into many cognitive, perceptual, and motor processes. For this reason, NWR is often used in assessment batteries to aid in verifying the presence of a reading or language disorder.

AIMS

To examine the extent to which child- and item-level factors predict the probability of a correct response on a non-word repetition (NWR) task in a sample of children with persistent speech sound disorders (P-SSDs) compared with their typically developing peers.

METHODS & PROCEDURES

A total of 40 American-English-speaking children were tested on an NWR task for which the stimuli were manipulated for phonological neighbourhood density and list length. Additional measures of vocabulary and word reading were also administered.

OUTCOMES & RESULTS

Children who were typically developing were 1.82 times more likely than children with P-SSD to respond correctly. The item-level factor of phonological neighbourhood density influenced performance, but only for the P-SSD group, and only at certain list lengths. Vocabulary and word-reading ability also influenced NWR task performance.

CONCLUSIONS & IMPLICATIONS

Children with P-SSD present as a complex and heterogeneous group. Multiple factors contribute to their ability to perform phonological tasks such as NWR. As such, attention to the item-level factors in screenings and assessments is necessary to ensure that appropriate decisions are made regarding diagnosis and subsequent treatment.

WHAT THIS PAPER ADDS

What is already known on the subject? Good expressive vocabulary is important for children with speech sound disorders; it can aid in their performance on phonological processing tasks like NWR. Nonword repetition may be a helpful test/ subtest to add to assessment batteries when evaluating children with speech sound disorders. What this paper adds to existing knowledge? Vocabulary and word reading abilities must also be measured for children with SSDs, to observe the bigger picture of their linguistic abilities. What are the potential or actual clinical implications of this work? The relation between word reading and speech sound production influences performance on phonological processing tasks.

Associations of Early-Life Threat and Deprivation With Executive Functioning in Childhood and Adolescence: A Systematic Review and Meta-analysis

IMPORTANCE

Many studies have demonstrated an association between early-life adversity (ELA) and executive functioning in children and adolescents. However, the aggregate magnitude of this association is unknown in the context of threat and deprivation types of adversity and various executive functioning domains.

OBJECTIVE

To test the hypothesis that experiences of deprivation are more strongly associated with reduced executive functioning compared with experiences of threat during childhood and adolescence.

DATA SOURCES

Embase, ERIC, MEDLINE, and PsycInfo databases were searched from inception to December 31, 2020. Both forward and reverse snowball citation searches were performed to identify additional articles.

STUDY SELECTION

Articles were selected for inclusion if they (1) had a child and/or adolescent sample, (2) included measures of ELA, (3) measured executive functioning, (4) evaluated the association between adversity and executive functioning, (5) were published in a peer-reviewed journal, and (6) were published in the English language. No temporal or geographic limits were set. A 2-reviewer, blinded screening process was conducted.

DATA EXTRACTION AND SYNTHESIS

PRISMA guidelines were used to guide data extraction and article diagnostics (for heterogeneity, small study bias, and p-hacking). Article quality was assessed, and data extraction was performed by multiple independent observers. A 3-level meta-analytic model with a restricted maximum likelihood method was used. Moderator analyses were conducted to explore heterogeneity.

MAIN OUTCOMES AND MEASURES

Primary outcomes included measures of the 3 domains of executive functioning: cognitive flexibility, inhibitory control, and working memory.

RESULTS

A total of 91 articles were included, representing 82 unique cohorts and 31 188 unique individuals. Deprivation, compared with threat, was associated with significantly lower inhibitory control (F1,90 = 5.69; P = .02) and working memory (F1,54 = 5.78; P = .02). No significant difference was observed for cognitive flexibility (F1,36 = 2.38; P = .12). The pooled effect size of the association of inhibitory control with deprivation was stronger (Hedges g = -0.43; 95% CI, -0.57 to -0.29) compared with threat (Hedges g = -0.27; 95% CI, -0.46 to -0.08). The pooled effect size of the association of working memory with deprivation was stronger (Hedges g = -0.54; 95% CI, -0.75 to -0.33) compared with threat (Hedges g = -0.28; 95% CI, -0.51 to -0.05).

CONCLUSIONS AND RELEVANCE

Experiences of both threat and deprivation in childhood and adolescence were associated with reduced executive functioning, but the association was stronger for exposure to deprivation. Efforts to address the consequences of ELA for development should consider the associations between specific dimensions of adversity and specific developmental outcomes.