Dimensions of executive functioning: Evidence from children

This study investigated dimensions of executive functioning in 8‐ to 13‐year‐old children. Three tasks from the Cambridge Neuropsychological Test Automated Battery (CANTAB), two tasks from the NEPSY battery and some additional executive function (EF) tests were administered to 108 children. In line with earlier work, modest correlations among EF measures were obtained (r < .4). Both exploratory and confirmatory factor analyses yielded three interrelated factors, which resembled those obtained by Miyake et al. (2000) and which were—with some reservations—labelled Working Memory (WM), Inhibition and Shifting. Age correlated with performance on most individual EF measures as well as Shifting and WM. The present findings are in agreement with contemporary views as to the simultaneous unity and diversity of EFs.     

Poly‐victimization and executive functions in junior college students

This study sought to characterize executive dysfunctions in poly‐victimized students without posttraumatic stress disorder (PTSD) symptoms and the relationship between neuropsychological and behavioral rating measures of executive functions (EFs). Based on self‐report data of exposure to victimization and PTSD symptoms, 259 junior college students aged 18–21 years were classified into four groups: poly‐victimization with PTSD symptoms (PVP), poly‐victimization without PTSD symptoms (PVnP), non‐poly‐victimization (nPV), and non‐victimization (nV). Respondents also completed the Behavior Rating Inventory of Executive Function‐Adult Version (BRIEF‐A). Of the 259 participants, 131 were administered a battery of neuropsychological tests from the Cambridge Neuropsychological Testing Automated Battery (CANTAB). The PVP group and the PVnP group performed worse than the nV group on most BRIEF‐A scales. When compared with the nPV group, the PVP group demonstrated poorer performance on the scales of Inhibit, Shift, Emotional Control, Initiate, and Working Memory, while the PVnP group performed more poorly on the Working Memory scale and the Task Monitor scale. For all BRIEF‐A scales, no significant differences were detected between the PVP group and the PVnP group. This study showed no between‐group differences for most of the neuropsychological tests except for the Stop Signal Task (SST), and no correlations between these two measures of EFs. Overall, we found evidence of an association between deficits in EFs and poly‐victimization. Although our study raises questions about the relationship between these two measures of EFs, it suggests that the use of the BRIEF‐A in conjunction with the CANTAB provides a more complete assessment of the executive dysfunctions.     

Interrelations Between Executive Function and Symptoms of Hyperactivity/Impulsivity and Inattention in Preschoolers: A Two Year Longitudinal Study

The present study, including children at risk for developing Attention Deficit Hyperactivity Disorder (ADHD), examined the idea that complex executive functions (EFs) build upon more simple ones. This notion was applied in the study of longitudinal interrelations between core EF components — simple and complex inhibition, selective attention, and working memory (WM) — at age 5 and 6 as well as their predictive relations to ADHD symptoms at age 7. The results showed that simple inhibition and selective attention at age 5 independently predicted complex inhibition and WM at age 6. In addition, EFs primarily predicted symptoms of inattention rather than hyperactivity/impulsivity even at this young age. Finally, age 6 complex inhibition was shown to act as a mediator in the relations between simple inhibition and selective attention at age 5 and symptoms of inattention at age 7. These findings provide novel longitudinal support for the theory that fundamental EF components show a progression with age toward more complex executive control (see Garon et al. Psychological Bulletin 134(1):31–60 2008). Further, complex inhibition, implicating both inhibition and WM, seems to be a particularly strong correlate of ADHD symptoms in young children and should as such be the focus of future studies examining the relation between cognitive function and ADHD symptoms from a developmental perspective.     

Construct Validity of Parent Ratings of Inhibitory Control

Recent literature has emphasized the need to examine executive functions (EF) in children using multiple sources, including both parent rating and performance-based measures. Computerized Go/No-Go tests, including commercially available continuous performance tests (CPTs), represent one of the most commonly used methods of assessing inhibitory control—a variable central to the executive function construct. We examined the relationship between parent ratings of inhibitory control and CPT performance in two mixed clinical samples. Experiment 1 examined 109 children ages 6–18 using the Behavior Rating Inventory of Executive Function (BRIEF; Gioia, Isquith, Guy, & Kenworthy, 2000) and the Conners' CPT-II (Conners, 2000). In this sample, ratings on the BRIEF Inhibit scale (mean T-score?=?62.3) were significantly higher than the CPT-II commissions score (mean T-score?=?50.7; p < .0001); and the BRIEF and CPT-II scores were not highly correlated (r?=???.12). Experiment 2 examined a sample of 131 children ages 7–18 using the BRIEF and the Tests of Variables of Attention (TOVA; Greenberg, 1996). In this sample, parent ratings on the BRIEF Inhibit scale (mean T-score?=?56.8) were similar to TOVA commissions scores (mean T-score?=?58.6; p?=?.33), although still poorly correlated (r?=??.02). Factor analyses exploring covariance between BRIEF scales CPT-II variables (Experiment 1) and between BRIEF and TOVA (Experiment 2) yielded similar findings. In both experiments, all eight BRIEF scales loaded on a single factor, with no overlap with either the CPT-II or the TOVA. In mixed outpatient clinical samples, the BRIEF appears to measure different elements of inhibitory control than those assessed by computerized continuous performance tests.     

Early executive functioning in a global context: Developmental continuity and family protective factors

This study extends the methodological and theoretical understanding of executive functions (EFs) in preschoolers from low‐ and middle‐income countries (LMIC). First, the authors describe a rigorous process of adapting and evaluating six EF tasks to produce a culturally and developmentally appropriate measure of emerging EFs in a large sample of at‐risk children in rural Pakistan. Next, the authors identify critical developmental and family factors that relate to preschoolers’ EFs over the first 4 years of life. Direct assessment of children's general cognitive skills at age two showed developmental continuity with EFs at age four, and these early cognitive skills mediated the effect of an antecedent parenting intervention on EFs as well as associations of targeted individual and family factors with EFs. Furthermore, directly assessed maternal cognitive capacities and observed maternal scaffolding uniquely predicted EFs in preschoolers. This study is also the first to demonstrate a significant overlap between direct assessments of IQ and EFs in young children from LMIC. Children's general intelligence mediated the associations of EFs with antecedent physical growth and cognitive skills as well as concurrent family factors (maternal verbal intelligence, maternal scaffolding, and home stimulation). After controlling for shared variance between preschoolers’ general intelligence and EFs, three factors emerged as unique predictors of EFs: exposure to an early parenting intervention, physical growth status at age two, and number of older siblings. The findings have important implications for the design of interventions that aim to improve EFs in young children in LMIC. A video abstract of this article can be viewed at https://vimeo.com/316329544/5abde94cd7     

Everyday executive function in focal onset pediatric epilepsy on the parent-report BRIEF2

Executive function (EF) difficulties are a core neuropsychological feature of pediatric epilepsy, and parent-report measures of EF concerns are an important complement to task-based EF measures. The Behavior Rating Inventory of Executive Function (BRIEF) has shown sensitivity to parent-reported EF concerns in epilepsy and other pediatric populations. We compared profiles of parent-reported EF concerns using the BRIEF and its revision, the BRIEF2, in 117 pediatric patients with focal onset epilepsy to examine the clinical utility of the revised scale. We then compared BRIEF2 profiles between patients and age- and gender-matched healthy controls. Among patients, profiles on the BRIEF did not globally differ from the BRIEF2, and agreement was very good across scales. Patients and controls differed significantly on the BRIEF2, with patients showing higher EF difficulties reported by parents across most scales. High rates of clinical elevation among patients emerged on the Task Monitor, Plan/Organize, Working Memory, and Shift scales. Younger age of epilepsy onset, chronic epilepsy, and right hemisphere seizure focus were associated with higher parent-reported EF concerns. Findings suggest that the BRIEF2 demonstrates similar performance to the BRIEF among pediatric patients with focal onset epilepsy who are most at risk in the areas of task monitoring, working memory, planning and organization, and flexibility. These findings are informative when comparing literature across versions and provide additional insight into the nature of parent-reported EF difficulties among children with focal onset epilepsy.     

Executive Functions in Children and Adolescents with Turner Syndrome: A Systematic Review and Meta-Analysis

Turner syndrome (TS) is a genetic disorder, affecting 1/2500 to 1/3000 live female births, induced by partial or total deletion of one X chromosome. The neurocognitive profile of girls with TS is characterized by a normal Verbal IQ and weaknesses in visual-spatial, mathematics, and social cognitive domains. Executive functions (EFs) impairments have also been reported in these young patients. However, methodological differences across studies do not allow determination of which EFs are impaired and what is the magnitude of these impairments. The aim of this review was to clarify the EF profile of children and adolescents with TS. Sixteen samples, from thirteen studies, were included in the current meta-analysis. EFs measures used in these studies were classified into working memory, inhibitory control, cognitive flexibility, or higher-order EFs tasks in accordance with Diamond’s model, Annual Review of Psychology, 64, 135–168 (2013). Results confirmed that girls with TS had significant executive impairments with effect sizes varying from small (inhibitory control) to medium (cognitive flexibility) and large (working memory, higher-order EFs). Analyses by task revealed that cognitive inhibition may be more impaired than the other inhibitory control abilities. Heterogeneity across cognitive flexibility measures was also highlighted. Between-sample heterogeneity was observed for three tasks and the impact of participants’ characteristics on EFs was discussed. This meta-analysis confirms the necessity to assess, in patients living with TS, each EF by combining both visual and verbal tasks. Results also underline that, when studying girls with TS’ executive profile, it is important to explore the impact of moderator variables, such as IQ, parental socio-economic status, TS karyotype, psychiatric comorbidities, and hormonal treatment status.     

Visuo-Spatial Working Memory Span: A Sensitive Measure of Cognitive Deficits in Children With ADHD

Working memory (WM) has been hypothesised to be impaired in attention-deficit/hyperactivity disorder (ADHD). However, there are few studies reported on tests measuring visuo-spatial WM (VSWM) in ADHD. Some of these studies used paradigms including episodic memory, others only used low memory loads. In the present study we used a VSWM test that has not been used previously in ADHD research. The sensitivity of the VSWM test and a choice reaction time (CRT) test was evaluated in a pilot study by comparing them to two commonly used tests in ADHD-research; the Continuous Performance Test (CPT) and a Go/no-go test, in children with and without ADHD. The groups differed significantly in performance on the VSWM test (P<.01) and CRT (P<.05) but not on the CPT (P>.1) or on the Go/no-go test (P>.1). The results from the VSWM and CRT tests were replicated in a larger sample of participants (80 boys; 27 boys with ADHD and 53 controls, mean age 11.4 years). The difference between the groups was significant for both the VSWM test (P<.01) and the CRT test (P<.01). The effect size (ES) of the VSWM test was 1.34. There was a significant age-by-group interaction on the VSWM test, with larger group differences for the older children (P<.01). Our results show that the VSWM test is a sensitive measure of cognitive deficits in ADHD and it supports the hypothesis that deficits in VSWM is a major component of ADHD.     

The Nature and Organization of Individual Differences in Executive Functions: Four General Conclusions

Executive functions (EFs)-a set of general-purpose control processes that regulate one's thoughts and behaviors-have become a popular research topic lately and have been studied in many subdisciplines of psychological science. This article summarizes the EF research that our group has conducted to understand the nature of individual differences in EFs and their cognitive and biological underpinnings. In the context of a new theoretical framework that we have been developing (the unity/diversity framework), we describe four general conclusions that have emerged from our research. Specifically, we argue that individual differences in EFs, as measured with simple laboratory tasks, (1) show both unity and diversity (different EFs are correlated yet separable); (2) reflect substantial genetic contributions; (3) are related to various clinically and societally important phenomena; and (4) show some developmental stability.     

The feasibility and acceptability of assessing inhibitory control and working memory among adolescents via an ecological momentary assessment approach

Early adolescence is a critical period for the development of executive function (EF). EF deficits are associated with increased engagement in multiple health risk behaviors and may be influenced by momentary factors, such as state mindfulness and physical activity. Ecological momentary assessment (EMA) leverages the increasing ubiquity of smart-phones to assess moment-to-moment changes in neurocognition and behavior with minimal recall bias and high ecological validity. As such, EMA is a promising method for delivering performance-based EF tasks and assessing the degree to which EF is influenced by momentary variation in its putative antecedents (e.g. state mindfulness and PA). This study adapts the (1) State Mindfulness Attention Awareness Scale, (2) physical activity/sedentary behavior recall items, (3) complex symmetry span working memory task, and (4) the child flanker inhibitory control task into an EMA tool delivered via iPhone using Inquisit Web. This tool was piloted with a sample of 32 seventh graders over a 72 h period. Participants’ posttest survey responses indicated that they found these study activities to be enjoyable, non-burdensome, not overly difficult, and preferable to pencil-and-paper instruments. Baseline correlations between flanker task performance and both BRIEF inhibitory control (σ = .23) and working memory subscales (σ = .34) were moderate. Correlations between symmetry span working memory task performance and BRIEF inhibitory control (σabsolute = .28; σpartial = .16) and working memory subscales (σabsolute = .19; σpartial = .15) were slightly lower, demonstrating associations consistent with previous studies. This study supports the feasibility and acceptability of administering two common performance-based EF tasks to adolescents via an EMA approach.     

The malleability of executive function in early childhood: Effects of schooling and targeted training

Executive function (EF), its importance for scholastic achievement and the question of whether or not EF is malleable, have become a topic of intense interest. Education or schooling is often seen as effective approaches to enhance EF due to the specific school‐related requirements as compared to kindergarten or pre‐school. However, no study to date has investigated whether targeted training focusing on those domains might be comparable with regular schooling in improving EF and fluid intelligence (Gf). The aim of the present study was to replicate and extend the previously demonstrated schooling effects on EF by using a school‐cutoff design, and to further investigate whether a theoretically motivated intervention targeting specific EF, i.e., working memory (WM) or inhibitory control (IC), could achieve comparable effects with schooling in both, WM and IC, as well as Gf. 91 6‐year‐old kindergarteners and first‐graders with similar chronological age participated the study. We compared the performance of a first‐grade schooling group with that of two kindergarten training groups as well as a business‐as‐usual kindergarten control group. Participants were assessed in WM, IC and Gf at baseline, immediately after the intervention (posttest), as well as 3 months after training completion (follow‐up). The results showed that the schooling group indeed outperformed the kindergarten groups at baseline in several cognitive tasks. Furthermore, both the WM and IC training showed pronounced gains in the trained tasks, as well as varying degrees of improvement in non‐trained outcome measures. Most importantly, both training groups achieved comparable performance with the schooling group, which was especially apparent in Gf at follow‐up. Our findings provide further evidence for the malleability of EF demonstrating that both, long‐term and short‐term interventions can facilitate the acquisition of those important skills, and as such, our work has important implications for educational practice.     

Executive Function Among Preschool Children: Unitary Versus Distinct Abilities

Working memory (WM) and inhibitory control (IC) are considered related but separable executive functions (EFs) among adults and adolescents. Although available evidence suggests that these constructs have not diverged, especially among younger preschool children, questions remain regarding the age at which separable factors emerge.This study used confirmatory factor analysis to test a 2-factor model of EF among 289 preschool children whose ages ranged from 45 to 63 months (M?=?55.74, SD?=?7.56). As hypothesized, the model including separate but related factors provided a significantly better fit than a unitary model, indicating the presence of distinct WM and IC factors. Based on evidence that WM and IC measured during preschool relate differently to a variety of academic and behavioral outcomes, it was hypothesized that a model including separate factors for each EF would fit the observed data better than a single-factor model. Although the two-factor model provided the best fit for the full sample, the correlation between WM and IC factors was significantly higher for younger (??=?.95) than older (??=?.68) children, indicating increasing divergence as a function of age.     

Construct validity of parent ratings of inhibitory control.

Recent literature has emphasized the need to examine executive functions (EF) in children using multiple sources, including both parent rating and performance-based measures. Computerized Go/No-Go tests, including commercially available continuous performance tests (CPTs), represent one of the most commonly used methods of assessing inhibitory control - a variable central to the executive function construct. We examined the relationship between parent ratings of inhibitory control and CPT performance in two mixed clinical samples. Experiment 1 examined 109 children ages 6-18 using the Behavior Rating Inventory of Executive Function (BRIEF; Gioia, Isquith, Guy, & Kenworthy, 2000) and the Conners' CPT-II (Conners, 2000). In this sample, ratings on the BRIEF Inhibit scale (mean T-score = 62.3) were significantly higher than the CPT-II commissions score (mean T-score = 50.7; p < .0001); and the BRIEF and CPT-II scores were not highly correlated (r = - .12). Experiment 2 examined a sample of 131 children ages 7-18 using the BRIEF and the Tests of Variables of Attention (TOVA; Greenberg, 1996). In this sample, parent ratings on the BRIEF Inhibit scale (mean T-score = 56.8) were similar to TOVA commissions scores (mean T-score = 58.6; p = .33), although still poorly correlated (r = -.02). Factor analyses exploring covariance between BRIEF scales CPT-II variables (Experiment 1) and between BRIEF and TOVA (Experiment 2) yielded similar findings. In both experiments, all eight BRIEF scales loaded on a single factor, with no overlap with either the CPT-II or the TOVA. In mixed outpatient clinical samples, the BRIEF appears to measure different elements of inhibitory control than those assessed by computerized continuous performance tests.     

Executive functions and processing speed in children with mild to borderline intellectual disabilities and externalizing behavior problems

Several studies suggest impaired executive functions (EFs) in children with externalizing behavior problems and average intelligence (e.g., IQ > 85). Even though children with mild to borderline intellectual disabilities (MBID) are at higher risk of developing externalizing behavior problems compared to children with average intelligence, it is not yet clear if impaired EFs are also associated with the occurrence of externalizing behavior problems in children with MBID. In the current study, we therefore assessed three EF components (inhibition, cognitive flexibility, and working memory) as well as processing speed in children with MBID and externalizing behavior problems (n = 71) versus children with MBID with no such problems (n = 70). This was accomplished using a well-established computerized test battery. Even after IQ was controlled for, the children with MBID and externalizing behavior problems showed more impaired working memory performance. Differences for inhibition performance and processing speed were also found but less consistent across the tasks used to measure these aspects of EF. Cognitive flexibility was not more impaired in children with both MBID and externalizing behavior problems relative to children with MBID only. Our findings highlight working memory as a potential target to enhance the treatment of children with MBID and externalizing behavior problems.     

Genetic and environmental influences on executive functions and intelligence in middle childhood

Executive functions (EFs) and intelligence (IQ) are phenotypically correlated. In twin studies, latent variables for EFs and IQ display moderate to high heritability estimates; however, they show variable genetic correlations in twin studies spanning childhood to middle age. We analyzed data from over 11,000 children (9- to 10-year-olds, including 749 twin pairs) in the Adolescent Brain Cognitive Development (ABCD) Study to examine the phenotypic and genetic relations between EFs and IQ in childhood. We identified two EF factors—Common EF and Updating-Specific—which were both related to IQ (rs = 0.64–0.81). Common EF and IQ were heritable (53%–67%), and their genetic correlation (rG = 0.86) was not significantly different than 1. These results suggest that EFs and IQ are phenotypically but not genetically separable in middle childhood, meaning that this phenotypic separability may be influenced by environmental factors.     

Social information processing skills link executive functions to aggression in adolescents with mild to borderline intellectual disability

Executive Functions (EFs) have been associated with aggression in children and adolescents. EFs as higher-order cognitive abilities are assumed to affect cognitive functions such as Social Information Processing (SIP). We explored SIP skills as a mediating mechanism linking EFs to aggression in adolescents with mild to borderline intellectual disability (MBID with IQ from 50–84), a high risk group for aggressive behaviors and EF impairments. A total of 153 adolescents (M_age = 15.24, SD = 1.35; 54% male) with MBID participated. Focused attention, behavioral inhibition, and working memory were tested with multiple neurocognitive tasks to define latent EF constructs. Participants responded to a video-based SIP task. A latent construct for aggression was defined by caretaker, teacher, and adolescent self-reports of aggression (Child Behavior Check List, Teacher Report Form, and Youth Self Report). Structural equation modeling was performed to test mediation. Results were consistent with mediation of the relation between focused attention and aggression by SIP, namely via hostile interpretations and self-efficacy for aggression. Behavioral inhibition was linked to aggression, but this relation was not mediated by SIP. The relation between working memory and aggression was mediated by SIP, namely via hostile interpretations, aggressive response generation and via self-efficacy for aggressive responses. Bearing the cross-sectional design in mind, support was found for SIP skills as a mechanism linking EFs, in particular focused attention and working memory, to aggression, providing a viable explanation for the high vulnerability of adolescents with MBID for aggression.     

Development of norms for executive functions in typically-developing Indian urban preschool children and its association with nutritional status

Executive functions (EFs) are essential and important for achieving success in children’s everyday lives and play a fundamental role in children’s cognitive, academic, social, emotional and behavioral functioning. A cross-sectional study was carried out to develop age- and sex-specific norms for EFs using the Behavior Rating Inventory of Executive Function – Preschool Version (BRIEF-P) among 2- to 5-year-olds from urban Bangalore, India. In addition, the association between EFs and anthropometric measures, a marker of nutritional status, is also examined. Primary caregivers of 412 children, equally distributed by age and sex, participated. Raw scores for each domain and indices were converted to standard t-scores and percentiles were computed. A t-score at or above 63 corresponding to the 90th percentile was considered as the cutoff for executive dysfunction in this sample. The prevalence of executive dysfunction is 10% based on the Global Executive Composite score of the BRIEF-P. The cutoff score for identifying executive dysfunction using existing United States (US) norms is higher compared to the cutoff score obtained in the current study. Therefore, using US norms for Indian children could result in the prevalence of executive dysfunction been underestimated. Multiple linear regression analysis revealed that stunted and underweight children have significantly elevated EF scores after adjusting for age, sex and socioeconomic status (SES; p < .01). A greater understanding of EFs in preschool children is important for the early identification of executive dysfunction and implementing interventions to improve their future prospects. This study also shows that undernourished children are more likely to have executive dysfunction.     

Interpersonal Violence,Depression, and Executive Function

This study considers links between the number of types of violence to which women have been exposed, depression, and executive functions (EFs). Substantial research has established EF deficits among depressed individuals as well as individuals exposed to trauma. Studies have also indicated a relationship between trauma exposure and depressive symptoms across a range of traumatic events, such as combat exposure, motor vehicle accidents, natural disasters, and assaults. This study examines this relationship in an ethnically diverse community sample of 93 women exposed to interpersonal violence who completed a battery of EF tasks that assessed processing speed, working memory, response inhibition, and set shifting. Women reported an average of 5.8 types of interpersonal violence events. The number of types of interpersonal violence events was significantly related to depressive symptoms, although not EF performance. Specific EFs, such as working memory and response inhibition, were positively related to depressive symptoms.     

Working memory resources in young children with mathematical difficulties

Kyttälä, M., Aunio, P. & Hautamäki, J. (2010). Working memory resources in young children with mathematical difficulties. Scandinavian Journal of Psychology, 51 , 1–15.
Working memory (WM) ( Baddeley, 1986, 1997 ) is argued to be one of the most important cognitive resources underlying mathematical competence ( Geary, 2004 ). Research has established close links between WM deficits and mathematical difficulties. This study investigated the possible deficits in WM, language and fluid intelligence that seem to characterize 4- to 6-year-old children with poor early mathematical skills before formal mathematics education. Children with early mathematical difficulties showed poor performance in both verbal and visuospatial WM tasks as well as on language tests and a fluid intelligence test indicating a thoroughly lower cognitive base. Poor WM performance was not moderated by fluid intelligence, but the extent of WM deficits was related to language skills. The educational implications are discussed.     

Mental Set Shifting in Childhood: The Role of Working Memory and Inhibitory Control

The role of working memory (WM) and inhibition in mental set shifting was examined from an individual difference perspective in children aged 5–14 years (N = 117). Using the Hearts and Flowers task the rationale of the present study was to directly test the theoretical assumption that mental set shifiting in childhood primarily builds on WM and inhibitory processes. Theoretical predictions about WM and inhibitory demands in the congruent and incongruent conditions of the Hearts and Flowers task were also considered because these blocks underlie relevant measures of set shifting. The findings show that both WM and inhibition (extracted as factors in confirmatory factor analysis) are important for set shifting but that this general association is driven by the link between these executive functions (EFs) and the goal‐representation aspect (i.e. global switch costs) of shifting, rather than to the actual switch‐implementation process (i.e. local switch costs). In addition, our findings are novel in showing that, despite a substantial correlation between the two EF components, it was the variance specific to WM and inhibition that was important for mental set shifting. Copyright © 2014 John Wiley & Sons, Ltd.