Evaluación de la función ejecutiva en una población escolar con síntomas de déficit de atención e hiperactividad

Capturing Subtle Neurocognitive Differences in Children with and without Tourette Syndrome through a Fine-Grained Analysis of Design Fluency Profiles

BACKGROUND

Tourette syndrome (TS) can be accompanied by neurocognitive impairment. Only a few studies have focused on executive function assessment in TS using design fluency, providing preliminary results. This study aimed to characterize the detailed design fluency profile of children with TS compared with neurotypical children, while addressing the central concern of frequent comorbidities in studies on TS by considering tic severity and attention-deficit/hyperactivity disorder (ADHD) symptoms and diagnosis.

METHODS

Sixty-one children aged between 6 and 15 years participated and were divided into a TS group (n = 28 (with ADHD n = 15)) and a control group (n = 33). Our objective was addressed by examining a wide range of measures of the Five-Point-Test, presumably sensitive to frontostriatal dysfunction. The total number of designs, repetitions, repetition ratio, unique designs, and numerical, spatial, and total strategies were examined for the total duration of the test (global measures) and at five equal time intervals (process measures).

RESULTS

The TS group produced significantly fewer numerical strategies. Groups did not differ in other global or process measures. ADHD did not affect performance.

CONCLUSIONS

Children with TS do not inherently show general executive dysfunction but may present with subtle neurocognitive characteristics here revealed by comprehensive design fluency profiles.

Effects of Physical Activity, Exercise and Sport on Executive Function in Young People with Attention Deficit Hyperactivity Disorder: A Systematic Review

Attention deficit hyperactivity disorder (ADHD) is a neurodevelopmental disorder that negatively affects the inattention, disorganization, and/or hyperactivity–impulsivity in children and adolescents who suffer from it, included cases being reported that continue into adulthood. This disorder impairs social, academic, emotional, psychological, and health system functioning due to its high cost of treatment. The present systematic review aims to analyze the effects of physical activity, exercise, and sports on the executive function in children and adolescents diagnosed with ADHD through the scientific literature. The results show that the practice of physical activity, exercise, or sport produces improvements in executive function in children and adolescents diagnosed with ADHD, mainly through aerobic exercise. A 20 min session of physical activity, sport, or exercise leads to improvements in executive functions in children and adolescents with ADHD. It can be concluded that the practice of physical activity, exercise, and sport generate improvements on executive functions in children and adolescents with ADHD, mainly through aerobic exercise.

Moderator Role of Monitoring in the Inhibitory Control of Adolescents With ADHD

Objective: The aim of this research was to analyze the role of monitoring in the causal relationship between inhibitory control and symptoms of combined ADHD. Method: It has been conducted a quantitative investigation of two phases. Results: In the first study, a moderation model was analyzed (N = 144 adolescents with combined ADHD), where monitoring was considered as a moderating variable in the causal relationship between the inhibitory control and the symptomatology of ADHD F(3, 140) = 28.03, p < .001; R² = .37. In the second study, the model through an experimental study was tested (N = 52 adolescents with and without ADHD) where it was found that adolescents with ADHD improve in their inhibitory control when they receive external support to the monitoring F(1, 50) = 21.38, p < .001, η² = .30. Conclusion: Results suggest that monitoring compensates the poor performance of inhibitory control in adolescents with ADHD, which is a contribution to the theoretical construction of ADHD and to the treatments proposed for this condition because it goes beyond the classic conception of a causality chain among the deficit of inhibitory control and ADHD symptomatology to propose a new explanation about this disorder, where neuropsychology intervention of monitoring would diminish ADHD's symptomatology impact on adolescents.

Design Fluency in Children with ADHD and Comorbid Disorders

BACKGROUND

Attention deficit/hyperactivity disorder (ADHD) is often associated with frontal executive impairment in children. Oppositional defiant disorder (ODD) and anxiety disorders (AD) frequently accompany ADHD, but the impact of these comorbid disorders on cognition remains elusive. The five-point test (FPT), a design fluency task, has been shown to be sensitive to neurological damage, specifically to frontal lobe lesions in patients with brain injuries. The purpose of this study was to compare the performances of neurotypical children with that of children with ADHD, ADHD-ODD, and ADHD-AD on the FPT in order to examine whether these groups could be distinguished from one another based on their cognitive profile.

METHODS

A total of 111 children aged 8 to 11 years old participated in the study. Six measures from the FPT were used to characterize their performance.

RESULTS

Statistically significant differences between groups were observed for five of the six FPT measures. Essentially, children with ADHD-ODD made more repeated designs than the three other groups (control p > 0.001, ADHD p = 0.008, ADHD-AD p = 0.008), while children with ADHD-AD produced fewer total and correct designs than the control and ADHD groups (p = 0.009).

CONCLUSIONS

This suggests that comorbidities have an additive impact on the cognitive profile of children with ADHD. Design fluency may be a sensitive measure for capturing the subtle cognitive deficits that are likely to be involved in these disorders.

Evaluation of the diagnostic implications of Das-Naglieri cognitive assessment system in children with attention deficit hyperactivity disorder

BACKGROUND

Attention deficit hyperactivity disorder (ADHD) is a neurodevelopmental characterized by attention deficit, hyperactivity, emotional impulses and difficulty with cognitive functions. The Das-Naglieri Cognitive Assessment System (DN: CAS), as a theory-driven assessment kit, was explored based on Planning, Attention, Simultaneous, and Successive Theory (PASS). Recent researches have tried to explore the sensitivity and specificity of DN: CAS in diagnosing ADHD; nevertheless, these studies were performed in a small study population. The following study explores the cognitive functions in ADHD by the DN: CAS and to evaluate the DN: CAS's diagnostic value in ADHD.

METHODS

A total of 135 children with ADHD and 140 healthy controls were enrolled to evaluate cognitive function by the DN: CAS. ROC curve and the area under the curve (AUC) were applied to evaluate the diagnostic value of DN: CAS on ADHD.

RESULTS

Compared with healthy controls, children with ADHD had significantly lower scores in Planning, Simultaneous (Verbal-Spatial Relations), Attention in the four Subtests of DN: CAS, as well as the total scores. ROC analysis indicated that Planning and Attention of DN: CAS had good classification accuracy in diagnosing ADHD with AUCs of 0.808 and 0.730, respectively.

CONCLUSIONS

The planning and attention assessment of DN: CAS revealed high sensitivity and specificity in diagnosing ADHD, thus suggesting that DN: CAS might be an effective tool in diagnosing ADHD.

Memory and intellectual styles: Performance of students with learning disabilities

Abstract Studies addressing issues related to information processing are necessary to understand some of the explanatory aspects of the changes in the learning process. The objective of the this study was to evaluate memory and intellectual styles in Elementary and Middle school students diagnosed with dyslexia and Attention Deficit Hyperactivity Disorder and in students without learning disabilities. A total of 370 students from public schools were individually evaluated using the Rey Complex Figure Test and the Thinking Styles Inventory – Revised II. The results showed significant differences in the memory condition between students with Attention Deficit Hyperactivity Disorder and those without learning disabilities. Significant differences in the scores of the Thinking Styles Inventory were also found between the three groups evaluated. Memory was negatively correlated with the conservative style. The difference between the groups and the correlation between these instruments pointed to the need for further research to assess these variables in the groups of students with learning disabilities.

Exploring the dynamics of design fluency in children with and without ADHD using artificial neural networks

The neuropsychology of attention deficit/hyperactivity disorder (ADHD) has been extensively studied, with a general focus on global performance measures of executive function. In this study, we compared how global (i.e., endpoint) versus process (i.e., dynamic) measures of performance may help characterize children with and without ADHD using a design fluency task as a case study. The secondary goal was to compare the sensitivity of standard versus connectionist statistical models to group differences in cognitive data. Thirty-four children diagnosed with ADHD and 37 children without ADHD aged 8-11 years old were tested on the Five-Point Test. The continuous process measure of performance, indexed as the number of produced designs at each consecutive 1 minute interval during 5 minutes, was analyzed against the discrete process measure, that is, the number of designs between first and last intervals and the standard global performance measure of total number of produced designs. Results show that the continuous process measure distinguished the two groups better than the two other measures. The detailed observation of production patterns revealed a decreasing linear trajectory in children without ADHD that contrasts with the flat, but fluctuating productivity pattern of children with ADHD. With regards to the second goal, results show that the connectionist and standard methods are equally sensitive to group differences for the three types of measures. This illustrates the utility of quantitative process measures together with the connectionist method in neuropsychological research and suggests great potential for a dynamical approach to cognition.

Evidence of an association between 10/10 genotype of DAT1 and endophenotypes of attention deficit/hyperactivity disorder

INTRODUCTION

Genetic variance of attention deficit-hyperactivity disorder (ADHD) is a strong determinant of this disorder. The 40 base pairs (bp) variable number tandem repeat (VNTR) located in the 3' untranslated region (UTR) of DAT1 gene increases the expression of the dopamine transporter. Therefore, DAT1 has been associated with susceptibility to ADHD.

OBJECTIVE

To determine the association between the VNTR of DAT1 and the phenotype of ADHD or its endophenotypes in a sample of children aged between 6 and 15 years from Bogotá.

SUBJECTS AND METHODS

We selected 73 patients with ADHD and 54 controls. WISC test was applied in all subjects and executive functions were assessed. The VNTR of DAT1 was polymerase chain reaction-amplified. Data regarding population genetics and statistical analysis were obtained. Correlation and association tests between genotype and neuropsychological testing were performed.

RESULTS

The DAT1 polymorphism was not associated with ADHD (P=.85). Nevertheless, the 10/10 genotype was found to be correlated with the processing speed index (P<.05). In the hyperactivity subtype, there was a genotypic correlation with some subtests of executive function (cognitive flexibility) (P≤.01). In the combined subtype, the 10/10 genotype was associated with verbal comprehension index of WISC (P<.05).

CONCLUSIONS

A correlation was found between DAT1 VNTR and the subtest "processing speed index" of WISC and the subtest "cognitive flexibility" of executive functions. To our knowledge, this is the first report to assess DAT1 gene in a Colombian population.

Evidence of association between SNAP25 gene and attention deficit hyperactivity disorder in a Latin American sample

Attention deficit hyperactivity disorder (ADHD) is one of the most highly heritable behavioral disorders in childhood, with heritability estimates between 60 and 90 %. Family, twin and adoption studies have indicated a strong genetic component in the susceptibility to ADHD. The synaptosomal-associated protein of molecular weight 25 kDa (SNAP25) is a plasma membrane protein known to be involved in synaptic and neural plasticity. Animal model studies have shown that SNAP25 gene is responsible for hyperkinetic behavior in the coloboma mouse. In recent studies, several authors reported an association between SNAP25 and ADHD. In this study, we used a case-control approach to analyze the possible association of two polymorphisms of SNAP25 for possible association with ADHD in a sample of 73 cases and 152 controls in a Colombian children population. Polymorphisms are located in 3' untranslated region of SNAP25, positions T1065G and T1069C. We found a significant association with the GT haplotype (rs3746554|rs1051312) of SNAP25 (p = 0.001). Evidence of association was also found for the G/G genotype of rs3746554 (p = 0.002) and C/C genotype of rs1051312 (p = 0.009). This is the first study in a Latin American population. Similar to other studies, we found evidence of the association of SNAP25 and ADHD.