Assessment of executive functioning in childhood epilepsy: The Tower of London and BRIEF

Children and adolescents with epilepsy are known to demonstrate executive function dysfunction, including working memory deficits and planning deficits. Accordingly, assessing specific executive function skills is important when evaluating these individuals. The present investigation examined the utility of two measures of executive functions—the Tower of London and the Behavioral Rating Inventory of Executive Functioning (BRIEF)—in a pediatric epilepsy sample. Ninety clinically referred children and adolescents with seizures were included. Both the Tower of London and BRIEF identified executive dysfunction in these individuals, but only the Tower of London variables showed significant relations with epilepsy severity variables such as age of epilepsy onset, seizure frequency, number of antiepileptic medications, etc. Further, the Tower of London and BRIEF variables were uncorrelated. Results indicate that objective measures of executive function deficits are more closely related to epilepsy severity but may not predict observable deficits, as reported by parents. Comprehensive evaluation of such deficits, therefore, should include both objective measures as well as subjective ratings from caregivers.     

Assessment of executive functioning in childhood epilepsy: the Tower of London and BRIEF

Children and adolescents with epilepsy are known to demonstrate executive function dysfunction, including working memory deficits and planning deficits. Accordingly, assessing specific executive function skills is important when evaluating these individuals. The present investigation examined the utility of two measures of executive functions-the Tower of London and the Behavioral Rating Inventory of Executive Functioning (BRIEF)-in a pediatric epilepsy sample. Ninety clinically referred children and adolescents with seizures were included. Both the Tower of London and BRIEF identified executive dysfunction in these individuals, but only the Tower of London variables showed significant relations with epilepsy severity variables such as age of epilepsy onset, seizure frequency, number of antiepileptic medications, etc. Further, the Tower of London and BRIEF variables were uncorrelated. Results indicate that objective measures of executive function deficits are more closely related to epilepsy severity but may not predict observable deficits, as reported by parents. Comprehensive evaluation of such deficits, therefore, should include both objective measures as well as subjective ratings from caregivers.     

Frequency of Scale Elevations and Factor Structure of the Behavior Rating Inventory of Executive Function (BRIEF) in Children and Adolescents With Intractable Epilepsy

The Behavior Rating Inventory of Executive Function (BRIEF) is a standardized rating scale that provides information about the nature and extent of executive function deficits displayed by children and adolescents in daily life. BRIEF protocols completed by parents of 80 children with intractable epilepsy were evaluated with respect to prevalence and severity of scale elevations in the sample, and also with respect to factor structure. Overall, the sample was rated as having significantly more executive function problems than healthy children in the BRIEF standardization sample; elevations on the Working Memory and Plan/Organize scales were most frequently seen. Fully 36% of the sample had four or more significantly elevated scales. However, 31% of the sample had no clinically elevated scales, indicating that executive difficulties, though frequent, are not necessarily characteristic of all children with severe epilepsy. As in the validation studies reported in the manual, a two-factor solution emerged from a principal factor analysis of BRIEF scales. However, the factor structure as given in the manual was not entirely replicated; specifically, the Monitor scale was found to load equivalently on both factors. The results of this study suggest that a substantial proportion of children with intractable epilepsy display significant executive function deficits in daily life. Research into the relationship of BRIEF scores to other measures of executive functioning in children with epilepsy is needed to further clarify its clinical utility.     

Cognitive estimations as a measure of executive dysfunction in childhood epilepsy

Children and adolescents with epilepsy are known to demonstrate executive function deficits. Despite prior work that has shown that cognitive estimation tasks are sensitive to executive dysfunction in children, such tasks have not been studied in children with epilepsy. This is particularly important given the fact that executive tasks have heretofore shown poor ecological validity, and it has been speculated that estimation tasks may show stronger ecological validity than other executive tests. One hundred and thirteen clinically referred children and adolescents with epilepsy were included. The Biber Cognitive Estimations Test was sensitive to cognitive dysfunction, with about half showing impairments on this task in comparison to age-matched normative data; the most frequently impaired subscales were quantity estimation and time estimation. Moreover, the Biber Cognitive Estimation Test showed moderate correlations with not only overall intellectual functions and academic achievement but also other commonly administered tests of executive functions, including digit span, Trailmaking, and the Tower of London but not with the contingency naming test. Cognitive estimations were also modestly correlated with age of epilepsy onset but not other epilepsy-severity variables such as number of antiepilepsy drugs (AEDs) or seizure frequency. Unfortunately, the hypothesis that the Biber Cognitive Estimation Test would show strong ecological validity was not supported, as it showed weak relations with parent-reported executive function deficits. The significance and limitations of this investigation are discussed.     

Frequency of scale elevations and factor structure of the Behavior Rating Inventory of Executive Function (BRIEF) in children and adolescents with intractable epilepsy.

The Behavior Rating Inventory of Executive Function (BRIEF) is a standardized rating scale that provides information about the nature and extent of executive function deficits displayed by children and adolescents in daily life. BRIEF protocols completed by parents of 80 children with intractable epilepsy were evaluated with respect to prevalence and severity of scale elevations in the sample, and also with respect to factor structure. Overall, the sample was rated as having significantly more executive function problems than healthy children in the BRIEF standardization sample; elevations on the Working Memory and Plan/Organize scales were most frequently seen. Fully 36% of the sample had four or more significantly elevated scales. However, 31% of the sample had no clinically elevated scales, indicating that executive difficulties, though frequent, are not necessarily characteristic of all children with severe epilepsy. As in the validation studies reported in the manual, a two-factor solution emerged from a principal factor analysis of BRIEF scales. However, the factor structure as given in the manual was not entirely replicated; specifically, the Monitor scale was found to load equivalently on both factors. The results of this study suggest that a substantial proportion of children with intractable epilepsy display significant executive function deficits in daily life. Research into the relationship of BRIEF scores to other measures of executive functioning in children with epilepsy is needed to further clarify its clinical utility.     

The WISC-V in children and adolescents with epilepsy

Despite its popularity in the neuropsychological evaluation of children, the utility of the Wechsler Intelligence Scale for Children – Fifth Edition (WISC-V) has not yet been investigated in children with epilepsy. Eighty clinically referred children and adolescents with epilepsy were administered the WISC-V as part of a comprehensive assessment and scores were compared to matched controls from the WISC-V standardization sample. T tests compared WISC-V indices and subtests between patients and controls and Chi-square analyses compared the rates of low scores. Correlational analyses assessed the relationships between epilepsy severity variables (e.g., age of onset, duration of epilepsy, number of antiepileptic drugs, seizure frequency). All WISC-V composites and subtests were significantly lower in patients versus controls and the rate of low scores was higher in patients than controls for all composites and subtests with the exception of Figure Weights. The Working Memory Index and Processing Speed Index were most sensitive to impairment, while the Verbal Comprehension Index and Fluid Reasoning Index were least sensitive. Of the epilepsy severity variables, age of seizure onset and number of antiepileptic drugs were strong predictors of deficits, whereas seizure frequency was the weakest predictor. Importantly, no significant differences were seen in children with right hemisphere epilepsy versus left on the five WISC-V composites, though a trend was seen towards a lower Visual-Spatial Index in those with right-sided focal seizures.     

How well do measures of inhibition and other executive functions discriminate between children with ADHD and controls?

The aim of the present study was to evaluate the usefulness of Barkley's (1997a) model of inhibition and executive functioning in describing the deficits associated with Attention Deficit Hyperactivity Disorder (ADHD). Besides group differences, the present study addressed the question of independent effects of inhibition and the other executive functions in discriminating between children with ADHD and controls and how well, in terms of sensitivity and specificity, these measures can classify the children into the correct group. The results showed that children with ADHD differed significantly from controls with regard to measures of inhibition as well as all other executive function measures, except repetition of hand movements. In logistic regression models, three different measures tapping inhibition, working memory and emotion regulation were shown to be significant independent predictors of group membership. The sensitivity for these three variables as a set was 76.2, the specificity was 90.5, with a total of 86% of the sample correctly classified. When excluding the parental rating of emotion regulation, the overall classification rate decreased some, but was still relatively high in comparison with previous studies within this area of research.     

EDITORIAL

The aim of the present study was to evaluate the usefulness of Barkley’s (1997a) model of inhibition and executive functioning in describing the deficits associated with Attention Deficit Hyperactivity Disorder (ADHD). Besides group differences, the present study addressed the question of independent effects of inhibition and the other executive functions in discriminating between children with ADHD and controls and how well, in terms of sensitivity and specificity, these measures can classify the children into the correct group. The results showed that children with ADHD differed significantly from controls with regard to measures of inhibition as well as all other executive function measures, except repetition of hand movements. In logistic regression models, three different measures tapping inhibition, working memory and emotion regulation were shown to be significant independent predictors of group membership. The sensitivity for these three variables as a set was 76.2, the specificity was 90.5, with a total of 86% of the sample correctly classified. When excluding the parental rating of emotion regulation, the overall classification rate decreased some, but was still relatively high in comparison with previous studies within this area of research.     

Utility of the Behavior Rating Inventory of Executive Function – Preschool version (BRIEF-P) in young children with epilepsy

Executive functioning deficits are prominent in children with epilepsy. Although instruments, such as the Behavior Rating Inventory of Executive Function (BRIEF), are useful in detecting executive dysfunction in school-age children with epilepsy, little data are available for younger children. The present study evaluates the ability of the Behavior Rating Inventory of Executive Function – Preschool Version (BRIEF-P) to detect executive dysfunction in preschool-age children with epilepsy. Parents of 51 clinically referred children with epilepsy (age: M = 1.99 years, SD = 1.29 years, range = 2–5 years) completed the BRIEF-P. Using a cutoff t score of ≥65 as the threshold for impairment, the BRIEF-P’s ability to detect executive dysfunction within this clinical population was established. Additionally, correlational analyses were used to assess the relations between epilepsy severity factors and BRIEF-P indices. Epilepsy severity variables that were significantly related to BRIEF-P indices were entered into a linear regression model to explore their predictive ability. Emergent metacognition (emergent metacognition index [EMI]; 59%) and the global executive composite (43%) were the most frequently elevated indices. The most commonly elevated subscales were working memory (65%), inhibition (37%), and planning/organization (35%). Age of seizure onset, seizure frequency, and number of antiepileptic drugs were not significantly correlated with BRIEF-P indices. However, children with lower intellectual ability were rated as having greater executive dysfunction, specifically with EMI (r = ?.30). Still, intellectual functioning only accounted for a small percentage (9%) of the variance in EMI scores. The current pilot study demonstrates that the BRIEF-P shows promise in identifying executive dysfunction in preschool-age children with epilepsy.     

Executive Function and Emotional,Behavioral, and Social Competence Problems in Children with Epilepsy

Many researchers have reported elevated rates of emotional, behavioral, and social competence problems (EBSP) in children with epilepsy. Although executive function has been found to be associated with EBSP in children with typical development, almost no research has looked at the individual components of executive function as potential predictors of EBSP in children with epilepsy. This is surprising given the deficits in executive function in children with epilepsy. We investigated EBSP and executive function in 42 children with epilepsy, aged 6.0 to 18.1 years and found, as expected, that EBSP were associated with executive function in these children even after epilepsy-related variables, such as seizure type, were accounted for. However, different components of executive function were related to different emotional, behavioral, and social competence problems in these children. Shifting of mental sets was a significant predictor of emotional, behavioral, and social competence problems whereas inhibition was a significant predictor of behavioral problems. This suggests that different executive function profiles in children with epilepsy may place them at-risk for developing different types of emotional, behavioral, and social competence problems. These results may help researchers and clinicians develop new techniques to identify and treat emotional, behavioral, and social competence problems in children with epilepsy.     

Psychometric Evaluation of the Borderline Personality Disorder Severity Index-IV-Adolescent Version and Parent Version

The Borderline Personality Disorder Severity Index-IV-adolescent and parent versions (BPDSI-IV-ado/p) are DSM-IV based semi-structured interviews for the assessment of the severity of symptoms of borderline personality disorder (BPD) in adolescents. The present study evaluates the psychometric properties of the BPDSI-IV-ado/p. The interviews were administered to 122 adolescents, aged 14-19 years and their parents/caretakers who were referred to mental health centres for emotion regulation problems, and to 45 healthy controls. The interrater reliability and internal consistency of all nine subscales (following the nine BPD symptoms in DSM-IV) proved to be good to excellent. Discriminant, concurrent, and construct validity were satisfactory. Cut-off scores that optimize sensitivity and specificity were derived. Informant agreement between adolescents and parents/caretakers was modest. The results of this study suggest that the BPDSI-IV adolescent and parent versions are valid and reliable instruments for the assessment of BPD symptom severity in adolescents.     

Executive functioning: Developmental consequences on adolescents with histories of maltreatment

Research suggests that children exposed to maltreatment have deficits in executive functioning (EF) but few studies have focused on the adolescent age group. We investigated whether maltreated adolescents had lower EF abilities compared to a group of non‐maltreated adolescents. Forty adolescents with histories of child maltreatment, together with a comparison group of 40 non‐maltreated adolescents matched for age, completed a comprehensive battery of EF tasks. Hierarchical multiple regression analyses, controlling for IQ, were carried out using each of the EF measures as dependent variables to examine group differences. Maltreated adolescents had significantly lower performance than non‐maltreated adolescents on tasks assessing executive loaded working memory, fluency, and inhibition, although switching was not impaired. Emotional and behavioural difficulties (EBD) were included in additional regression analyses to examine whether these variables would explain the group differences. The inclusion of EBD variables had some effect on group differences, as expected, but did not eliminate them. These findings support the theory that impairments in EF may be one underlying reason why adolescents with histories of maltreatment struggle to cope both inside and outside the classroom.     

Performance on the Test of Memory Malingering in children with neurological conditions

Despite increasing interest in the use of performance validity tests with youth, relatively little is known about how children and adolescents with neurological diagnoses perform on these measures. The purpose of this study was to examine performance on the Test of Memory Malingering (TOMM) in a general pediatric neurologic sample. Data were obtained from 266 consecutive patients (mean age = 13.0, SD = 3.7, range = 5–18) referred for a neuropsychological assessment in a tertiary care pediatric hospital. As part of a broader neuropsychological battery, patients were administered the TOMM. In this sample, 94% of children passed the TOMM. Pass rate was 87% for 5–7 year-olds but was ≥ 90% for all other ages. Children with a history of stroke had the lowest pass rate (86%), with other diagnostic groups scoring ≥ 90%, including epilepsy, traumatic brain injury, and hydrocephalus. Lower TOMM performance was related to slower processing speed and weaker memory performance. The results support using the TOMM with children and adolescents who have neurological diagnoses. Caution may still be warranted when interpreting scores in those who are younger and/or who have more significant cognitive difficulty.     

Book Review

Performance-based measures and ratings of executive functions were examined in a sample of adolescents with attention deficit/hyperactivity disorder (ADHD) and comparison controls. Performance-based measures of executive function included inhibition, working memory, set shifting, and planning, and ratings of these same executive functions were completed by parents and teachers. Adolescents with ADHD demonstrated lower executive function performance than controls and displayed elevated ratings on the executive function ratings by parents and teachers. Significant associations were obtained between the performance-based measures and the parent and teacher ratings, but each measure was not uniquely associated with its respective scale on the rating scales. When performance-based measures and ratings were examined as predictors of ADHD status, the parent and teacher ratings entered as significant predictors of ADHD status. Further commonality analyses indicated that performance-based measures accounted for little unique variance in predicting ADHD status and also displayed little overlap with the behavioral ratings. These findings highlight the diagnostic utility of behavioral ratings of executive function in predicting ADHD status; however, behavioral ratings should not be assumed to be a proxy for performance on measures of executive function in clinical practice.     

An attempt to discriminate different types of executive functions in the Wisconsin Card Sorting Test

This study examined the roles of the phonological working memory and the central executive in the Wisconsin Card Sorting Test by altering the materials and the procedure of the task and using a dual-task design, in which cognitive abilities of normal participants were manipulated by performance of the secondary tasks selectively taxing the phonological loop or the central executive. The present study used three novel versions of the Wisconsin Card Sorting Test, namely the WCST-4 stimuli, the WCST-12-stimuli, and the WCST-12-stimuli-box, in all of which the participants were given the exact sorting criterion. So the tasks did not involve processes such as maintenance of inferences about the sorting criterion which would require phonological memory load. However, the tasks were assumed to require the executive process of response inhibition. In the WCST-4-stimuli condition no change was made to the WCST materials. In the other two conditions, relying on the assumption that the three-dimensional nature of the cards triggers inappropriate responses, unidimensional stimulus cards were used instead of the four normal three-dimensional WCST stimulus cards. The difference between these two conditions was that, in the WCST-12-stimuli-box condition, boxes were used to conceal the response cards previously sorted. The results supported Dunbar and Sussman's (1995) argument that some executive processes in the Wisconsin Card Sorting Test require the use of phonological store, and the present design was able to differentiate the type of executive functions that do not involve the use of a phonological loop from the ones that do. In addition, the results concerning manipulations of the visual aspects of the Wisconsin Card Sorting Test suggest that the three-dimensional nature of the WCST stimulus cards leads to an increase in the number of inappropriate responses produced with the executive secondary task interference.     

Self-Reported Depressive Symptoms Have Minimal Effect on Executive Functioning Performance in Children and Adolescents

The relation between mood and executive functioning in children and adolescents has not been previously reported. This study examined the association between self-reported depressive symptoms in both clinical outpatient and psychiatric inpatient samples to the following measures of executive functioning: the Controlled Oral Word Association Test, Animal Naming, Trail Making Test, and Wisconsin Card Sorting Test. Records from children and adolescents aged 7–17 years old with an IQ > 70 were examined. Data were gathered at either an outpatient neuropsychology clinic (n = 89) or an inpatient psychiatric hospital setting (n = 81). Mood was measured with the Children’s Depression Inventory. Generally, statistical associations between self-reported depressive symptoms and executive functioning were small and non-significant. The variance predicted by mood on measures of executive functioning was minimal (generally less than 2 %) for the total sample, the outpatient group, inpatient group, and a subgroup who endorsed elevated mood symptoms. These results suggest that impaired performance on measures of executive functioning in children and adolescents is minimally related to self-reported depressive symptoms.     

Measuring the development of executive control with the shape school

Although several neurodevelopmental and psychiatric disorders can emerge during the preschool period, there are comparatively few instruments to assess executive control. Evidence for validity of the Shape School (K. A. Espy, 1997) was examined in a sample of 219 typically developing young children. There was good evidence for validity, as Shape School performance variables were interrelated and were associated to other criterion measures considered to measure aspects of executive control. Also suggesting validity, the Shape School variables varied as a function of whether the task demands (a) were executive, (b) required inhibition of a prepotent response or context-controlled selection among relevant stimulus-response sets, and (c) included unitary or concurrent processing. The Shape School may be an effective tool by which to measure executive control in young children who have atypical developmental patterns.     

Changing patterns of neuropsychological functioning in children living at high altitude above and below 4000 m: a report from the Bolivian Children Living at Altitude (BoCLA) study

The brain is highly sensitive to environmental hypoxia. Little is known, however, about the neuropsychological effects of high altitude residence in the developing brain. We recently described only minor changes in processing speed in native Bolivian children and adolescents living at approximately 3700 m. However, evidence for loss of cerebral autoregulation above this altitude (4000 m) suggests a potential threshold of hypoxia severity over which neuropsychological functioning may be compromised. We conducted physiological and neuropsychological assessments in 62 Bolivian children and adolescents living at La Paz (～3700 m) and El Alto (～4100 m) in order to address this issue. Groups were equivalent in terms of age, gender, social class, schooling, parental education and genetic admixture. Apart from percentage of hemoglobin saturated with oxygen in arterial blood (%SpO(2)), participants did not differ in their basal cardiac and cerebrovascular performance as explored by heart rate, mean arterial pressure, end-tidal carbon dioxide, and cerebral blood flow velocity at the basilar, anterior, middle and posterior cerebral arteries. A comprehensive neuropsychological assessment was administered, including tests of executive functions, attention, memory and psychomotor performance. Participants living at extreme altitude showed lower levels of performance in all executive tests (Cohen effect size = -0.91), whereas all other domains remained unaffected by altitude of residence. These results are compatible with earlier physiological evidence of a transitional zone for cerebral autoregulation at an altitude of 4000 m. We now show that above this threshold, the developing brain is apparently increasingly vulnerable to neuropsychological deficit.     

Laterality of the frontal aslant tract (FAT) explains externalizing behaviors through its association with executive function

We investigated the development of a recently identified white matter pathway, the frontal aslant tract (FAT) and its association with executive function and externalizing behaviors in a sample of 129 neurotypical male and female human children ranging in age from 7 months to 19 years. We found that the FAT could be tracked in 92% of those children, and that the pathway showed age‐related differences into adulthood. The change in white matter microstructure was very rapid until about 6 years, and then plateaued, only to show age‐related increases again after the age of 11 years. In a subset of those children (5–18 years; n = 70), left laterality of the microstructural properties of the FAT was associated with greater attention problems as measured by the Child Behavior Checklist (CBCL). However, this relationship was fully mediated by higher executive dysfunction as measured by the Behavior Rating Inventory of Executive Function (BRIEF). This relationship was specific to the FAT—we found no relationship between laterality of a control pathway, or of the white matter of the brain in general, and attention and executive function. These findings suggest that the degree to which the developing brain favors a right lateralized structural dominance of the FAT is directly associated with executive function and attention. This novel finding provides a new potential structural biomarker to assess attention deficit hyperactivity disorder (ADHD) and associated executive dysfunction during development.