Inhibitory Deficits in Reading Disability Depend on Subtype: Guessers but not Spellers

In this study, children with the guessing subtype of dyslexia (who read fast and inaccurately) were compared with children with the spelling subtype (who read slowly and accurately) on three aspects of executive functioning (EF): response inhibition, susceptibility to interference from irrelevant information, and planning. It was found that guessers were impaired in their ability to inhibit inappropriate responding on all tasks used to assess EF (the stop signal task, the Stroop task, and the Tower of London task). This raises the question of whether the specific reading disorder of guessers may be linked to the same executive deficits which underlie ADHD. In order to unite a fast/inaccurate reading style with executive deficiencies, an attempt is made to incorporate the concept of executive control into models of lexical activation.     

Inhibitory control during sentence reading in dyslexic children.

The present study focused on the nature of the reading disability of children with the guessing subtype of dyslexia (who read fast and inaccurately). The objective was to separate the excitatory account of their reading disturbance (i.e., in guessers the words' resting levels of activation are oversensitive to semantic context) from the inhibitory account (i.e., guessers tend to react prematurely to (false) candidate words that are activated in the lexicon). To disentangle the above accounts, guessers and normal readers were presented with a sentential priming task (SPT). In the SPT, subjects had to determine whether the final word of a sentence was semantically congruent or incongruent with the sentence, but had to inhibit their 'congruent' or 'incongruent' response in case of an occasionally presented pseudoword. To evoke guessing, each pseudoword closely resembled either a valid congruent or incongruent word. Guessing referred to prematurely accepting a pseudoword as a word that either appropriately or inappropriately completed the sentence. The extent to which subjects guessed at word meaning was evidenced by the false recognition rates (FRR) of the misspelled terminal words. Analyses on the FRRs of the pseudowords showed that guessers had significantly more difficulty in suppressing the 'go tendency' triggered by the pseudowords. It was concluded that the impulsive reading style of guessers should be ascribed to a less efficient suppression mechanism rather than to excessive reliance on contextual information. Specifically, the data were explained by assuming that the availability of the pseudoword's candidate meaning activated the hand to respond with, and that guessers found difficulty in suspending this response until they analyzed all letters in the stimulus and they could be sure of its spelling.     

Inhibitory Control During Sentence Reading in Dyslexic Children

The present study focused on the nature of the reading disability of children with the guessing subtype of dyslexia (who read fast and inaccurately). The objective was to separate the excitatory account of their reading disturbance (i.e., in guessers the words’ resting levels of activation are oversensitive to semantic context) from the inhibitory account (i.e., guessers tend to react prematurely to (false) candidate words that are activated in the lexicon).

To disentangle the above accounts, guessers and normal readers were presented with a sentential priming task (SPT). In the SPT, subjects had to determine whether the final word of a sentence was semantically congruent or incongruent with the sentence, but had to inhibit their ‘congruent’ or ‘incongruent’ response in case of an occasionally presented pseudoword. To evoke guessing, each pseudoword closely resembled either a valid congruent or incongruent word. Guessing referred to prematurely accepting a pseudoword as a word that either appropriately or inappropriately completed the sentence. The extent to which subjects guessed at word meaning was evidenced by the false recognition rates (FRR) of the misspelled terminal words.

Analyses on the FRRs of the pseudowords showed that guessers had significantly more difficulty in suppressing the ‘go tendency’ triggered by the pseudowords. It was concluded that the impulsive reading style of guessers should be ascribed to a less efficient suppression mechanism rather than to excessive reliance on contextual information. Specifically, the data were explained by assuming that the availability of the pseudoword’s candidate meaning activated the hand to respond with, and that guessers found difficulty in suspending this response until they analyzed all letters in the stimulus and they could be sure of its spelling.     

The Role of Executive Function in Arithmetic Problem-Solving Processes: A Study of Third Graders

This study investigated the roles of different executive function (EF) components (inhibition, shifting, and working memory) in 2-step arithmetic word problem solving. A sample of 139 children aged 8 years old and regularly attending the 3rd grade of primary school were tested on 6 EF tasks measuring different EF components, a reading task and a reading comprehension task, an arithmetic facts task evaluating basic knowledge of calculation, and three 2-step arithmetic word problems. Multiple hierarchical regression analyses were conducted to investigate the roles of the different EF components in the various phases of the problem-solving process. The results showed that EF affects the various phases of problem solving differently over and above calculation knowledge and reading abilities. The implications of these findings are discussed in relation to further understanding the role of cognitive skills in mathematical problem solving and in relation to instructional approaches that may increase children’s performance on 2-step arithmetic word problems.     

“热”执行对注意缺陷多动障碍和阅读障碍儿童言语工作记忆的影响

ADHD儿童在与背外侧前额叶(DLPFC)相关的"冷"执行功能上的缺陷已大量证实,但在与眼眶和中前额叶皮层(OMPFC)相关的"热"执行功能上,ADHD儿童是否存在缺陷则未可知。与儿童赌博任务实验范式(该任务中"热"启动对"冷"执行起到抑制作用)不同,本研究考察趣味言语N-back任务是否对ADHD和阅读障碍儿童的成绩有促进作用。枯燥N-back任务考察的是言语工作记忆的纯认知特征,而趣味任务则卷入了"热"执行对"冷"执行的影响。结果表明,在枯燥任务上,ADHD和阅读障碍儿童的成绩均明显低于正常儿童,二者之间差异不显著,在趣味任务成绩上,ADHD儿童与正常儿童的成绩没有显著差异,而阅读障碍儿童成绩落后于正常控制组和ADHD组,在成绩变化的趋势上,ADHD儿童在趣味任务上成绩明显提高,而阅读障碍儿童则无明显改善。结果说明ADHD和阅读障碍儿童的言语工作记忆均存在明显的缺陷,但是机制不同,"热"执行对提高ADHD的言语工作记忆有明显的促进作用,ADHD的"冷"执行缺陷能够通过"热"执行的调节得到改善。     

Quantitative analyses of schooling effects on executive function in young children.

Developmental studies have demonstrated the utility of select executive function (EF) tasks for the early diagnosis of specific learning-related problems (e.g., Snow, 1998). However, previous data demonstrating schooling effects on EF measures suggests potential pitfalls in clinical interpretation. In the present study three common EF measures, (Wisconsin Card Sort, Thurstone Word Fluency, and a mazes task) in addition to a VIQ estimating task, were administered to a cross-section of 115 children aged 7 to 9. Using a school-entrance cut-off design the unique contributions of formal schooling versus age-related changes to performance on the EF measures were examined. Schooling effects were both task and age-dependent supporting the conclusion that the proper use of EF measures with children in this age range depends upon consideration of factors beyond that usually depicted in net-effect models.     

Quantitative Analyses of Schooling Effects on Executive Function in Young Children

Developmental studies have demonstrated the utility of select executive function (EF) tasks for the early diagnosis of specific learning-related problems (e.g., Snow, 1998). However, previous data demonstrating schooling effects on EF measures suggests potential pitfalls in clinical interpretation. In the present study three common EF measures, (Wisconsin Card Sort, Thurstone Word Fluency, and a mazes task) in addition to a VIQ estimating task, were administered to a cross-section of 115 children aged 7 to 9. Using a school-entrance cut-off design the unique contributions of formal schooling versus age-related changes to performance on the EF measures were examined. Schooling effects were both task and age-dependent supporting the conclusion that the proper use of EF measures with children in this age range depends upon consideration of factors beyond that usually depicted in net-effect models.     

Attention and executive functioning in infancy: Links to childhood executive function and reading achievement

This study provides the first analyses connecting individual differences in infant attention to reading achievement through the development of executive functioning (EF) in infancy and early childhood. Five‐month‐old infants observed a video, and peak look duration and shift rate were video coded and assessed. At 10 months, as well as 3, 4, and 6 years, children completed age‐appropriate EF tasks (A‐not‐B task, hand game, forward digit span, backwards digit span, and number Stroop). Children also completed a standardized reading assessment and a measure of verbal intelligence (IQ) at age 6. Path analyses on 157 participants showed that infant attention had a direct statistical predictive effect on EF at 10 months, with EF showing a continuous pattern of development from 10 months to 6 years. EF and verbal IQ at 6 years had a direct effect on reading achievement. Furthermore, EF at all time points mediated the relation between 5‐month attention and reading achievement. These findings may inform reading interventions by suggesting earlier intervention time points and specific cognitive processes (i.e. 5‐month attention).     

Cognitive and emotional aspects of self-regulation in preschoolers

The goal of the present study was to examine the contribution of executive function (EF) and social cognition to individual differences in emotion regulation (ER) in preschool children. Sixty 3-, 4-, and 5-year-old children were administered a battery of EF tasks, two theory of mind tasks, a measure of verbal ability, and an ER task. In addition, parents completed the Behavior Rating Inventory of Executive Functioning—Preschool Version (BRIEF-P). Performance on the theory of mind tasks as well as parental ratings of executive function was not related to performance on the ER task. However, a component of EF (i.e., inhibition) approached significance with children's displays of positive behaviors during the ER task. Verbal ability was related to the regulation of positive but not negative emotions. Parental ratings of shifting accounted for a significant amount of variance in parental ratings of ER, even after controlling for verbal ability. The findings are discussed in the context of different conceptualizations of the developmental relation between ER and EF.     

Patterns of Attachment in Frequently and Infrequently Reading Mother—Child Dyads

This study explored the relationship between the quality of the mother–child attachment and how often mothers read to their children. Eighteen children who were read to infrequently were matched to a group of children who were read to daily, for sex, age, and socioeconomic status. The children's mothers read them a booklet, mother and child were observed in a reunion episode, the children completed the Peabody Picture Vocabulary Test (Dunn, 1965) and Frostig's (1966) test for spatial orientation, and the mothers were given the Adult Attachment Interview (George, Kaplan, & Main, 1984). The mothers in the frequently reading dyads did not need to discipline their child to focus on the reading task as often as the mothers in the infrequently reading dyads did. Mothers whose attachment to their child was less secure spent less time reading to their child and had more troublesome episodes during the reading session than mothers whose attachment to their child was more secure. The security of the mother-child attachment was related to the mothers' representation of their relationship with their parents, and mothers who had a secure relationship with their child read more frequently to their child than did mothers who had an insecure relationship with their child.     

Inhibition and shifting in children with learning deficits in arithmetic and reading

The executive functions of inhibition and shifting were studied in arithmetic-disabled children, reading-disabled children, reading plus arithmetic-disabled children, and controls (N = 74). Measures involved the rapid naming of objects, digits, letters, or quantities with or without additional task requirements that reflected inhibition or shifting. Also, the Making Trails task, reflecting shifting, was administered. For tasks without executive demands, arithmetic-disabled children were slower in the naming of digits and quantities, whereas reading-disabled children were slower in the naming of digits and letters. For the executive tasks, arithmetic-disabled children as well as reading plus arithmetic-disabled children were impaired on the Making Trails task and on an object naming task that required both inhibition and shifting. Reading-disabled children exhibited no problems in executive functioning. Furthermore, it was shown that reading plus arithmetic-disabled children experienced the combination of problems that characterize children with a single learning deficit.     

Comorbid Problems in ADHD: Degree of Association,Shared Endophenotypes,and Formation of Distinct Subtypes. Implications for a Future <Emphasis Type="Italic">DSM</Emphasis>

We aimed to assess which comorbid problems (oppositional defiant behaviors, anxiety, autistic traits, motor coordination problems, and reading problems) were most associated with Attention-Deficit/Hyperactivity Disorder (ADHD); to determine whether these comorbid problems shared executive and motor problems on an endophenotype level with ADHD; and to determine whether executive functioning (EF)—and motor-endophenotypes supported the hypothesis that ADHD with comorbid problems is a qualitatively different phenotype than ADHD without comorbid problems. An EF—and a motor-endophenotype were formed based on nine neuropsychological tasks administered to 816 children from ADHD—and control-families. Additional data on comorbid problems were gathered using questionnaires. Results indicated that oppositional defiant behaviors appeared the most important comorbid problems of ADHD, followed by autistic traits, and than followed by motor coordination problems, anxiety, and reading problems. Both the EF—and motor-endophenotype were correlated and cross-correlated in siblings to autistic traits, motor coordination problems and reading problems, suggesting ADHD and these comorbid problems may possibly share familial/genetic EF and motor deficits. No such results were found for oppositional defiant behaviors and anxiety. ADHD in co-occurrence with comorbid problems may not be best seen as a distinct subtype of ADHD, but further research is warranted. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

The measurement of executive function at age 5: psychometric properties and relationship to academic achievement

This study examined the psychometric properties and criterion validity of a newly developed battery of executive function (EF) tasks for use in early childhood. The battery was included in the Family Life Project (FLP), a prospective longitudinal study of families who were oversampled from low-income and African American families at the birth of a new child (N = 1,292). Ninety-nine percent (N = 1,036) of children who participated in the age 5 home visit completed 1 or more (M = 5.8, Mdn = 6) of the 6 EF tasks. Results indicated that tasks worked equally well for children residing in low-income and not low-income homes, that task scores were most informative about the ability level of children in the low-average range, that performance on EF tasks was best characterized by a single factor, and that individual differences on the EF battery were strongly related to a latent variable measuring overall academic achievement, as well as to individual standardized tests that measured phonological awareness, letter-word identification, and early math skills.     

Parent-report and performance-based measures of executive function assess different constructs

A total of 405 children of 5–18 years of age were administered performance-based and parent-report measures of executive function (EF), and measures of motor, attention, reading, and mathematics performance. Attention, reading, and mathematics abilities were associated with a parent-report measure of EF. Reading and mathematics abilities were also associated with performance-based measures of EF, including the Animal Sorting, Inhibition, and Response Set subtests of the Developmental NEuroPSYchological Assessment-II. In contrast, motor functioning was only associated with performance-based measures of EF. Findings suggest that different constructs of EF are measured by parent-report versus performance-based measures, and that these different constructs of EF are associated with different neurodevelopmental processes.     

Investigating the links between the subcomponents of executive function and academic achievement: a cross-cultural analysis of Chinese and American preschoolers

Little is known about how components of executive function (EF) jointly and uniquely predict different aspects of academic achievement and how this may vary across cultural contexts. In the current study, 119 Chinese and 139 American preschoolers were tested on a battery of EF tasks (i.e., inhibition, working memory, and attentional control) as well as academic achievement tasks (i.e., reading and mathematics). Results demonstrate that although working memory performance in both cultures was comparable, Chinese children outperformed American children on inhibition and attentional control tasks. In addition, the relation between components of EF and achievement was similar in the two countries. Working memory uniquely predicted academic achievement, with some intriguing patterns in regard to tasks requiring complex processing. Inhibition uniquely predicted counting but did not uniquely predict calculation. Attentional control predicted most aspects of achievement uniformly and was the most robust predictor for reading in both countries. In sum, the data provide insight into both cultural variability and consistency in the development of EF during early childhood.     

New insights into visual-motor integration exploring process measures during copying shapes

The link between visual-motor integration (VMI) and executive functions (EF) has been repeatedly documented in preschool children. VMI is often assessed using the Copy Design task measuring the product, thereby neglecting the processes that lead to a specific copy. Furthermore, EF are assumed to be mainly involved when a task is new. The involvement of EF after minimal practice in VMI, however, is unknown. Therefore, the present study investigated product- (i.e., accuracy) and process-based measures, namely velocity, and fluency, in five consecutive trials of copying shapes. Contributions of manual dexterity and EF to both VMI product and VMI processes across five trials were investigated in a sample of 5- to 6-year-old kindergarten children. Results revealed that children did not copy the shapes more accurately across the five trials, but quicker and more fluently. In line with previous findings, children's performance on VMI, manual dexterity, and EF were interrelated. The results indicate that over and above the copy's accuracy, also fluency of copying is a crucial indicator of VMI, which is related to EF and manual dexterity. Furthermore, findings on the VMI–EF link point to strong EF involvement during copying when the task is new and to a decreasing EF involvement with increasing practice, already after five trials. New insights into VMI in preschool children are discussed with regard to underlying cognitive processes.     

Trait and state anxiety: Relations to executive functioning in an at-risk sample

Prior research with adults suggests mixed evidence for the relations of state and trait anxiety to prefrontal executive functions (EF). Trait anxiety is hypothesised to impair the efficiency of prefrontal areas and goal-directed attention and has been largely associated with poorer performance on executive functioning tasks. Fewer studies have investigated state anxiety, and the findings have been mixed. As studies of these processes in children have been limited by small sample sizes and a focus on working memory, we examine whether state and trait anxiety are associated with performance on two EF tasks in a sample of urban, low-income children, ages 9–12. Results indicated that higher trait anxiety predicted lower executive functioning on both tasks. In addition, higher state anxiety was related to better performance on the Stroop task. Results demonstrate that, consistent with the adult literature, higher trait anxiety is related to lower executive functioning in children.     

Executive function across the life span

The development and determinants of executive function (EF) were studied in children (mean age=8.8 years), young adults ( M= 22.3 years), and elderly adults (M = 7 years). EF was indexed by perseverative responding on two bidimensional sorting tasks (Visually Cued Color-Shape task and Auditorily Cued Number-Numeral task), and age-related changes in EF were considered in relation to estimates of conscious vs. unconscious memory that were obtained using the process dissociation procedure (PDP). Results revealed the rise and fall of EF across the life span, with significant quadratic trends found for performance on both sorting tasks and for the conscious recollection component (C) of the PDP task. Regression analyses indicated that PDP estimates of conscious memory accounted for variation in performance on the visual sorting task, but not on the auditory sorting task. The findings are discussed in terms of their implications for hierarchical models of EF and its development.     

Teaching reading and spelling: exclusion and stimulus equivalence

In Experiment 1, 7 nonreading children were exposed to a program designed to teach reading of 51 training words. The program featured an exclusion-based procedure in which the children (a) matched printed to dictated words and (b) constructed (copied) printed words with movable letters and named them. All children learned to read the training words. Five children also read generalization words and showed progress in spelling. Experiment 2 applied the program to 4 different children, omitting the word-construction task. They also learned to read the training words, but only 1 participant read generalization words. The data support a stimulus equivalence account of reading acquisition and suggest that reading generalization may be obtained, especially when the teaching program includes word construction.     

The Lexical Stroop Sort (LSS) picture-word task: a computerized task for assessing the relationship between language and executive functioning in school-aged children

The relationship between language development and executive function (EF) in children is not well understood. The Lexical Stroop Sort (LSS) task is a computerized EF task created for the purpose of examining the relationship between school-aged children’s oral language development and EF. To validate this new measure, a diverse sample of school-aged children completed standardized oral language assessments, the LSS task, and the widely used Dimensional Change Card Sort (DCCS; Zelazo, 2006) task. Both EF tasks require children to sort stimuli into categories based on predetermined rules. While the DCCS largely relies on visual stimuli, the LSS employs children’s phonological loop to access their semantic knowledge base. Accuracy and reaction times were recorded for both tasks. Children’s scores on the LSS task were correlated with their scores on the DCCS task, and a similar pattern of relationships emerged between children’s vocabulary and the two EF tasks, thus providing convergent validity for the LSS. However, children’s phonological awareness was associated with their scores on the LSS, but not with those on the DCCS. In addition, a mediation model was used to elucidate the predictive relationship between phonological awareness and children’s performance on the LSS task, with children’s vocabulary fully mediating this relationship. The use of this newly created and validated LSS task with different populations, such as preschoolers and bilinguals, is also discussed.