Spatial memory and executive functions in children

A computerized hidden pathway maze-learning task was used to examine the development of spatial memory and executive functions in 6- to 9-year-olds. Pathway length was manipulated to investigate the impact of increases in maze matrix size on these abilities. Analysis showed that maze matrix size (and ipso facto pathway length) and age interacted to affect executive functions but not spatial memory. Executive errors differed as a function of age on the most difficult maze. Results are discussed in terms of factors affecting the development of executive functions and spatial memory.     

Coordination of executive functions in monolingual and bilingual children

Two groups of 8-year-old children who were monolingual or bilingual completed a complex classification task in which they made semantic judgments on stimuli that were presented either visually or auditorily. The task requires coordinating a variety of executive control components, specifically working memory, inhibition, and shifting. When each of the visual and auditory tasks was presented alone, performance was comparable for children in the two groups. Combining the two modalities into a dual-task paradigm made the task more difficult, and on this combined task bilingual children maintained better accuracy than monolingual children, especially on the visual task. The results are interpreted in terms of the enhanced ability of bilingual children to coordinate the executive control components required in performing this complex task.     

Training and transfer effects of executive functions in preschool children

Executive functions, including working memory and inhibition, are of central importance to much of human behavior. Interventions intended to improve executive functions might therefore serve an important purpose. Previous studies show that working memory can be improved by training, but it is unknown if this also holds for inhibition, and whether it is possible to train executive functions in preschoolers. In the present study, preschool children received computerized training of either visuo‐spatial working memory or inhibition for 5 weeks. An active control group played commercially available computer games, and a passive control group took part in only pre‐ and posttesting. Children trained on working memory improved significantly on trained tasks; they showed training effects on non‐trained tests of spatial and verbal working memory, as well as transfer effects to attention. Children trained on inhibition showed a significant improvement over time on two out of three trained task paradigms, but no significant improvements relative to the control groups on tasks measuring working memory or attention. In neither of the two interventions were there effects on non‐trained inhibitory tasks. The results suggest that working memory training can have significant effects also among preschool children. The finding that inhibition could not be improved by either one of the two training programs might be due to the particular training program used in the present study or possibly indicate that executive functions differ in how easily they can be improved by training, which in turn might relate to differences in their underlying psychological and neural processes.     

Examining the development of attention and executive functions in children with a novel paradigm.

The development of attention and executive functions in normal children (7-12 years) was investigated using a novel selective reaching task, which involved reaching as rapidly as possible towards a target, while at times having to ignore a distractor. The information processing paradigm allowed the measurement of various distinct dimensions of behaviour within a single task. The largest improvements in vigilance, set-shifting, response inhibition, selective attention, and impulsive responding were observed to occur between the ages of 8 and 10, with a plateau in performance between 10 and 12 years of age. These findings, consistent with a step-wise model of development, coincide with the observed developmental spurt in frontal brain functions between 7 and 10 years of age, and indicate that attention and executive functions develop in parallel. This task appears to be a useful research tool in the assessment of attention and executive functions, within a single task. Thus it may have a role in determining which cognitive functions are most affected in different childhood disorders.     

Multivariate base rates for the assessment of executive functioning among children and adolescents

This study provides observed base rates of low executive functioning test scores among healthy children and adolescents, stratifies those base rates by narrow intellectual functioning and age groupings, and provides normative classification ranges to aid the interpretation of performances on the Delis-Kaplan Executive Function System (D-KEFS) in clinical practice and research. Participants included 875 children and adolescents between 8 and 19 years old from the D-KEFS normative sample (48% male; 52% female). Among these participants, 838 had complete data and were included in the current study. The racial/ethnic composition of the sample was: White (73.7%), African American (12.4%), Hispanic (11.1%), and other racial/ethnic backgrounds (2.7%). The Overall Test Battery Mean (OTBM) and the prevalence of low scores at various clinical cut-offs were calculated for the 13 primary scores from the D-KEFS Trail Making Test, Verbal Fluency Test, and Color-Word Interference Test. The OTBM and base rates were also calculated separately for those scores reflecting executive functioning (n = 7) and processing speed (n = 6). Healthy children and adolescents commonly obtained low scores on the D-KEFS tests considered here. Younger age, lower estimated full-scale intelligence quotient, and more test scores interpreted were associated with a greater frequency of low scores. Clinicians and researchers are encouraged to consider these multivariate base rates when assessing and attempting to identify executive functioning impairment among children and adolescents with the D-KEFS.     

Evaluation of executive functions in children and adolescents with familial Mediterranean fever

The aim of the present study was to investigate neuropsychological test performance in children and adolescents with familial Mediterranean fever (FMF). A total of 88 children and adolescents aged 8 to 17 years were included, 52 with FMF and 36 healthy controls. After the participants were administered the Children Depression Inventory (CDI) and the Screen for Child Anxiety Related Emotional Disorders (SCARED), they completed the battery tests of the Central Nervous System Vital Signs (CNSVS), a neurocognitive test battery, via computer. The battery calculates seven domain scores (Memory, Psychomotor Speed, Processing Speed, Reaction Time, Complex Attention, Executive Function, and Cognitive Flexibility) and a summary score (Neurocognition Index [NCI]). A statistically significant difference between the FMF and control groups was found in six out of seven domains, where the scores of the participants with FMF were found to be significantly lower than those of the control participants (p < .05). Although the mean Reaction Time score of the participants with FMF was found to be lower than that of the control participants, the finding was not statistically significant (p > .05). The mean CDI and SCARED scores of the participants with FMF were found to be significantly higher than those of the control participants (p < .05). Low scores in the Processing Speed and Psychomotor Speed domains of the CNSVS were significantly correlated with higher SCARED scores (r = ?.37, p = .01). Impaired cognitive functions should be taken into consideration in children and adolescents with FMF when assessing and managing this population.     

The role of executive functions in bilingual children with reading difficulties

To explore the joint effect of reading difficulties (RD) and bilingualism on executive functions, 190 children of four groups of 9–12 year‐olds (41 bilinguals with RD, 45 monolinguals with RD, 45 bilinguals without RD, and 59 monolinguals without RD) were examined on the Concentration game, Tower of Hanoi, and Stroop as measures of executive functioning tapping into inhibitory/attentional control, working memory and planning ability. The most prominent finding was that in terms of RD, the speed of performances decreased dramatically. This general decrease was more pronounced for bilingual children with RD than for their monolingual counterparts. In conclusion, the findings suggest that while bilinguals gain more from executive functions in normal reading, they lose in terms of RD. Such an outcome confirms that executive functions are essential components of both reading and bilingualism, which depending on whether reading conditions are normal or difficult will produce cognitive advantages or disadvantages. Further, it is argued that dissimilarity between the Farsi and Swedish languages may complicate handling of such a situation.     

Self-regulation and inhibition in comorbid ADHD children: an evaluation of executive functions

The relationship between executive function and comorbid diagnoses in ADHD children is examined. One hundred six children between 7 and 15 years of age are assessed using the Tower of London (TOL), a test of executive function, and the Kiddie Schedule of Affective Disorders and Schizophrenia, Present and Lifetime Version, a diagnostic interview. All children met the diagnostic criteria for ADHD. A majority of the children had comorbid anxiety disorders, mood disorders, or oppositional defiant disorder. Measures on the TOL are total move score, total initiation time, and total rule violations. Age is predictive in all three measures of executive function as assessed by the TOL. Gender is predictive of total initiation time and total rule violations. Comorbid disorders are found to not have significance on executive function as measured by the TOL. This study concludes that comorbid disorders may not affect executive function.     

The development of analogy making in children: Cognitive load and executive functions

The aim of the current study was to investigate the performance of 6-, 8-, and 14-year-olds on an analogy-making task involving analogies in which there are competing perceptual and relational matches. We hypothesized that the selection of the common relational structure requires the inhibition of other salient features, in particular, perceptual matches. Using an A:B::C:D paradigm, we showed that children’s performance in analogy-making tasks depends crucially on the nature of the distractors. Children chose more perceptual distractors having a common feature with C compared with A or B (Experiment 1). In addition, they were also influenced by unstructured random textures. When measuring reaction times instead of accurate responses, only the 8-year-olds’ reaction times were significantly influenced by perceptual distractors. The 6-year-olds seemed to select the first match they noticed, and the 14-year-olds were not influenced (or much less influenced) by featural distractors. These results are compatible with an analogy-making account based on varying limitations in executive functioning at different ages.     

Attention problems and executive functions in children with spina bifida and hydrocephalus.

This study addressed the incidence of Attention-Deficit/Hyperactivity Disorder (ADHD) subtypes in children with spina bifida meningomyelocele and shunted hydrocephalus (SBH) as well as differences in executive functions among these subtypes. Parent rating scales revealed that 31% of the group with SBH could be identified with AD/HD, mostly the Inattentive type (23%). The group with SBH differed from normal controls on cognitive measures of executive functions, but subtype differences were not significant. Multivariate tests showed that children with SBH were rated with greater difficulties on the Behavior Rating Inventory of Executive Function (BRIEF) compared to controls; those with SBH and any subtype of ADHD differed from those with SBH and no ADHD; and those with ADHD (Combined Type) differed significantly from those with ADHD (Predominantly Inattentive Type). Subtype differences on univariate tests in the latter comparison were significant on the BRIEF Inhibit scale, showing more disinhibition in those with SBH and ADHD (Combined Type), but no significant differences were apparent on the BRIEF Sustain, Shift, and Initiate scales. The results show that the incidence of ADHD in children with SBH exceeds the population rate, is represented by problems with inattention rather than with impulsivity and hyperactivity; and that as with non-brain injured individuals, subtype differences in cognitive function remain to more clearly delineated.     

Personality assessment screener in a primary care sample of low-income urban women

The diagnostic efficiency of the Personality Assessment Screener (PAS; Morey, 1997) total score was evaluated using selected scales from the Patient Health Questionnaire (Spitzer, Kroenke, & Williams, 1999), the fourth edition of the Personality Diagnostic Questionnaire (Hyler, 1994), and the Alcohol Use Disorders Identification Test (Saunders, Aasland, Babor, DeLaFuente, & Grant, 1993) as reference standards. Complete data were collected from 110 women seeking treatment at an urban family medicine training clinic. Total PAS scores were effective in identifying patients with mood disorders, cluster B personality disorders, and alcohol use disorders, but the optimum cut scores were higher than the cut score of 19 recommended by Morey (1997). The 10 PAS element scores showed good convergent and discriminant correlations with the reference measures. These findings support the utility of the PAS to screen for major forms of psychopathology in an urban primary care setting.     

Cognitive and behavioral rating measures of executive function as predictors of academic outcomes in children

Interrelations of two measurement methods (cognitive versus behavioral ratings) for executive function (EF) were examined and related to reading comprehension and math calculations in fourth and fifth grade students (n = 93) in the context of a diverse urban student population. Relations among measures within four EF processes (working memory, planning, inhibition and shifting) were modest; relations to academics were stronger. EF measures contributed to both academic outcomes even in the context of relevant covariates (age, language and educational program). Working memory was particularly important for reading comprehension across measurement type. Cognitive measures from all EF processes, particularly inhibition and planning, and behavioral ratings of working memory were important for math.     

Clinical and statistical approaches to the assessment of brain damage in children

In an attempt at innovation in the clinical versus statistical prediction controversy, the present research examined three methods of assessing organic brain damage in a sample of sixty-eight 9- to 14-year-old children. Methods compared were clinical judgment (CP); existing actuarial norms (EAN); and derived statistical prediction (DSP), based on three psychological tests. The results were as follows: (a) None of the methods classified subjects significantly better than chance (p<.05); (b) there was no significant difference (p<.05) among the methods in terms of their rates of accurate classification; (c) CP based on combined tests did not result in higher predictive accuracy than those based on an individual test; (d) CP made after receiving feedback on accuracy showed an increase in number of correct classifications over prior CP; and (e) CP based on knowledge of the statistical prediction in addition to test data showed a higher rate of correct classification than DSP alone.     

Relationships between cognitive and behavioral measures of executive function in children with brain disease.

This study addressed the clinical and construct validity of the Behavior Rating Inventory of Executive Function. (BRIEF: Gioia, Isquith, Guy, & Kenworthy, 2000), a questionnaire designed to tap behavioral aspects of executive functions in children. BRIEF profiles in early treated phenylketonuria (PKU; n=44), early treated hydrocephalus (n=45), frontal focal lesions (n=20) and controls (n=80) were examined. Clinical validity was supported through significant between-group comparisons, especially between the frontal focal lesion group and other groups. To examine construct validity, raw scores on cognitive executive function measures including the Contingency Naming Test (CNT), Rey Complex Figure (RCF), Tower of London (TOL), and Controlled Oral Word Association Test (COWAT), were correlated with BRIEF scale scores. Few significant correlations were found, indicating cognitive and behavioral measures appear to tap different constructs within the executive function domain. A dissociation was found between behavioral and cognitive impairments in the frontal as opposed to PKU and hydrocephalus groups. This is discussed in relation to underlying pathology, the cognitive measures used, and possible limitations in the BRIEF's usefulness for measuring behavioral executive dysfunction in groups only mildly affected by neurological compromise.     

The p factor in children: Relationships with executive functions and effortful control

Lower levels of self-regulation have been implicated in multiple psychological disorders. Despite conceptual overlap (broadly reflecting self-regulatory functions), executive functions (EF) and effortful control (EC) are rarely jointly studied in relation to broadband psychopathology. The present study investigated associations of correlated factors (internalizing-externalizing) and bifactor psychopathology models with EF and EC in a large (N = 895) childhood community sample (M_age = 11.54, SD_age = 2.25). Associations between both self-regulation constructs (EF and EC) with psychopathology were largely accounted for via a general psychopathology factor. However, EC evidenced stronger associations, questioning the utility of task-based EF measures to inform self-regulatory psychopathology.     

Developmental trajectories in toddlers' self-restraint predict individual differences in executive functions 14 years later: a behavioral genetic analysis

We examined whether self-restraint in early childhood predicted individual differences in 3 executive functions (EFs; inhibiting prepotent responses, updating working memory, and shifting task sets) in late adolescence in a sample of approximately 950 twins. At ages 14, 20, 24, and 36 months, the children were shown an attractive toy and told not to touch it for 30 s. Latency to touch the toy increased with age, and latent class growth modeling distinguished 2 groups of children that differed in their latencies to touch the toy at all 4 time points. Using confirmatory factor analysis, we decomposed the 3 EFs (measured with latent variables at age 17 years) into a Common EF factor (isomorphic to response inhibition ability) and 2 factors specific to updating and shifting. Less-restrained children had significantly lower scores on the Common EF factor, equivalent scores on the Updating-Specific factor, and higher scores on the Shifting-Specific factor than did the more-restrained children. The less-restrained group also had lower IQ scores, but this effect was entirely mediated by the EF components. Twin models indicated that the associations were primarily genetic in origin for the Common EF variable but split between genetics and nonshared environment for the Shifting-Specific variable. These results suggest a biological relation between individual differences in self-restraint and EFs, one that begins early in life and persists into late adolescence.     

Differential changes in the development of motor coordination and executive functions in children with motor coordination impairments

Cognitive and motor coordination skills of children with and without motor coordination impairments were examined with a one-year follow-up investigation. Initially, children were between 4 and 6 years old. Age-appropriate tests of executive functions (updating, switching, inhibition, interference control), motor coordination (the Movement Assessment Battery for Children-2) and fitness (the Körperkoordinations-Test für Kinder) were administered in two consecutive years. Several background variables (age, socioeconomic status, medical support, clinical interventions, leisure activities) and potential moderators (nonverbal intelligence, reaction time, visual perception) were controlled. The matched sample consisted of 48 control children and 48 children with motor coordination impairments. The children’s executive functions dramatically improved during the one-year period. With regard to motor coordination performance, half of the impaired children caught up to the control children’s level (“remission group”), while the remaining half showed no improvement (“persisting group”). Compared to the persisting group, the children in the remission group showed markedly better interference control at both measurement points. The correlation between executive functions and motor coordination is significant in the persisting group, but not in the remission group. The results of the study are discussed in the light of the role of executive functions, especially inhibition processes, for the automatization of motor coordination tasks.     

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.