Effects of coexisting disorders on cognition and behavior in children with ADHD

Dimensional associations between executive function processes and symptoms of ADHD, ASD, oppositional defiance and anxiety in young school-referred children

Executive function (EF) difficulties are implicated in Neurodevelopmental Disorders (NDDs), such as Autism Spectrum Disorder (ASD) and Attention Deficit Hyperactivity Disorder (ADHD). Because NDDs are highly comorbid and frequently co-occur with additional clinical problems, it is unclear how specific EF problems are associated with symptoms of ASD and ADHD, whilst accounting for co-occurring anxiety or oppositional defiance disorder (ODD) symptoms. The current study utilised a large sample of young children (n = 438, aged 4-8) referred to Cardiff University's Neurodevelopment Assessment Unit (NDAU) by teachers for cognitive and/or socio-emotional problems. As part of the referral process, the teachers completed the Strengths and Difficulties Questionnaire (SDQ), which revealed that most children displayed moderate to high hyperactivity (86%) and prosocial (73%) problems, as well as high levels of symptoms in other clinical domains (41% emotional, 61% conduct and 68% peer problems). Children completed tasks to assess episodic memory, cognitive inhibition, cognitive flexibility and visuomotor control, whilst parents completed questionnaires to measure symptoms of ASD, ADHD, anxiety and ODD. Dimensional analyses showed that poorer cognitive inhibition and visuospatial episodic memory were significantly associated with ADHD symptoms, whereas cognitive flexibility was negatively associated with ODD symptoms. Having more ASD symptoms was associated with fewer cognitive inhibition problems, whereas anxiety was associated with better cognitive flexibility. Our approach to assessment and analysis shows that specific cognitive processes are associated with distinct neurodevelopmental and clinical symptoms, which is ultimately relevant to early identification of and intervention for young children at risk of cognitive and/or socio-emotional problems.

ADGRL3, FGF1 and DRD4: Linkage and Association with Working Memory and Perceptual Organization Candidate Endophenotypes in ADHD

Attention deficit hyperactivity disorder (ADHD) is a highly heritable neurobehavioral disorder that affects children worldwide, with detrimental long-term consequences in affected individuals. ADHD-affected patients display visual-motor and visuospatial abilities and skills that depart from those exhibited by non-affected individuals and struggle with perceptual organization, which might partially explain impulsive responses. Endophenotypes (quantifiable or dimensional constructs that are closely related to the root cause of the disease) might provide a more powerful and objective framework for dissecting the underlying neurobiology of ADHD than that of categories offered by the syndromic classification. In here, we explore the potential presence of the linkage and association of single-nucleotide polymorphisms (SNPs), harbored in genes implicated in the etiology of ADHD (ADGRL3, DRD4, and FGF1), with cognitive endophenotypes related to working memory and perceptual organization in 113 nuclear families. These families were ascertained from a geographical area of the Caribbean coast, in the north of Colombia, where the community is characterized by its ethnic diversity and differential gene pool. We found a significant association and linkage of markers ADGRL3-rs1565902, DRD4-rs916457 and FGF1-rs2282794 to neuropsychological tasks outlining working memory and perceptual organization such as performance in the digits forward and backward, arithmetic, similarities, the completion of figures and the assembly of objects. Our results provide strong support to understand ADHD as a combination of working memory and perceptual organization deficits and highlight the importance of the genetic background shaping the neurobiology, clinical complexity, and physiopathology of ADHD. Further, this study supplements new information regarding an ethnically diverse community with a vast African American contribution, where ADHD studies are scarce.

Executive Functions in Neurodevelopmental Disorders: Comorbidity Overlaps Between Attention Deficit and Hyperactivity Disorder and Specific Learning Disorders

The present study examines the comorbidity between specific learning disorders (SLD) and attention deficit and hyperactivity disorder (ADHD) by comparing the neuropsychological profiles of children with and without this comorbidity. Ninety-seven schoolchildren from 8 to 14 years old were tested: a clinical sample of 49 children with ADHD (n = 18), SLD (n = 18) or SLD in comorbidity with ADHD (n = 13), and 48 typically-developing (TD) children matched for age and intelligence. Participants were administered tasks and questionnaires to confirm their initial diagnosis, and a battery of executive function (EF) tasks testing inhibition, shifting, and verbal and visuospatial updating. Using one-way ANOVAs, our results showed that all children in the clinical samples exhibited impairments on EF measures (inhibition and shifting tasks) when compared with TD children. A more specific pattern only emerged for the updating tasks. Only children with SLD had significant impairment in verbal updating, whereas children with ADHD, and those with SLD in comorbidity with ADHD, had the worst performance in visuospatial updating. The clinical and educational implications of these findings are discussed.

Anxiety Symptoms and Disorders in College Students With ADHD

Objective: This study examined anxiety symptoms and disorders in college students with ADHD. Method: Forty-six college students with ADHD and a matched group of students without ADHD participated. Participants completed self-report measures of anxiety symptoms and associated features, including worry, maladaptive beliefs about worry, panic symptoms, social anxiety, obsessive-compulsive symptoms, and self-efficacy. Participants also completed a diagnostic interview to assess lifetime and current anxiety disorders. Results: Participants with ADHD endorsed more maladaptive beliefs about worry, more obsessive-compulsive symptoms, and poorer self-efficacy compared with comparison participants. There were no group differences in rates of current anxiety disorders. Participants with ADHD were over 2 times more likely than comparison participants to endorse this lifetime history. Conclusion: College students with ADHD are more likely to have a lifetime history of an anxiety disorder and are at greater risk for some anxiety symptoms and associated features.

Intrinsic Cortico-Subcortical Functional Connectivity in Developmental Dyslexia and Developmental Coordination Disorder

Developmental dyslexia (DD) and developmental coordination disorder (DCD) are distinct diagnostic disorders. However, they also frequently co-occur and may share a common etiology. It was proposed conceptually a neural network framework that explains differences and commonalities between DD and DCD through impairments of distinct or intertwined cortico-subcortical connectivity pathways. The present study addressed this issue by exploring intrinsic cortico-striatal and cortico-cerebellar functional connectivity in a large (n = 136) resting-state fMRI cohort study of 8–12-year-old children with typical development and with DD and/or DCD. We delineated a set of cortico-subcortical functional circuits believed to be associated with the brain’s main functions (visual, somatomotor, dorsal attention, ventral attention, limbic, frontoparietal control, and default-mode). Next, we assessed, using general linear and multiple kernel models, whether and which circuits distinguished between the groups. Findings revealed that somatomotor cortico-cerebellar and frontoparietal cortico-striatal circuits are affected in the presence of DCD, including abnormalities in cortico-cerebellar connections targeting motor-related regions and cortico-striatal connections mapping onto posterior parietal cortex. Thus, DCD but not DD may be considered as an impairment of cortico-subcortical functional circuits.

Strategy Selection in ADHD Characteristics Children: A Study in Arithmetic

OBJECTIVE

It has been argued that ADHD characteristics children have difficulties in selecting the best strategy when they accomplish cognitive tasks. The detrimental influence of these poor strategy skills may be crucial for several aspects of academic achievement such as mathematical learning.

METHOD

Fourth- and fifth-grade children with ADHD symptoms and matched controls were asked to select the better of two rounding strategies in a computational estimation task (i.e., finding the best estimate of two-digit addition problems).

RESULTS

(a) Both control and ADHD children correctly executed a selected strategy, (b) ADHD children selected the best strategy less often than controls, (c) ADHD took more time to estimate sums of two-digit addition problems and provided poorer estimates, and (d) different factors predicted best strategy selections in each group.

CONCLUSION

These findings have important implications for further understanding the sources of differences in cognitive performance between ADHD and control children. (J. of Att. Dis. 2019; 23(1) 87-98).

Feedforward motor control in developmental dyslexia and developmental coordination disorder: Does comorbidity matter?

BACKGROUND AND AIM

Feedforward and online controls are two facets of predictive motor control from internal models, which is suspected to be impaired in learning disorders. We examined whether the feedforward component is affected in children (8-12 years) with developmental dyslexia (DD) and/or with developmental coordination disorder (DCD) compared to typically developing (TD) children.

METHODS

Children underwent a bimanual unloading paradigm during which a load supported to one arm, the postural arm, was either unexpectedly unloaded by a computer or voluntary unloaded by the subject with the other arm.

RESULTS

All children showed a better stabilization (lower flexion) of the postural arm and an earlier inhibition of the arm flexors during voluntary unloading, indicating anticipation of unloading. Between-group comparisons of kinematics and electromyographic activity of the postural arm revealed that the difference during voluntary unloading was between DD-DCD children and the other groups, with the former showing a delayed inhibition of the flexor muscles.

CONCLUSION

Deficit of the feedforward component of motor control may particularly apply to comorbid subtypes, here the DD-DCD subtype. The development of a comprehensive framework for motor performance deficits in children with learning disorders will be achieved only by dissociating key components of motor prediction and focusing on subtypes and comorbidities.

Cognitive Functioning in Adolescents with Self-Reported ADHD and Depression: Results from a Population-Based Study

This study aims to assess cognitive functioning differences among adolescents with retrospectively self-reported: ADHD and an onset of depression, only ADHD, only depression, and neither ADHD nor depression. Data from the Tracking Adolescents’ Individual Lives Survey (TRAILS) cohort was used in this study. Neuropsychological functioning was assessed in 1549 adolescents, at baseline and follow-up (mean ages 11 and 19 years). The Composite International Diagnostic Interview was used to classify adolescents into 4 groups: ADHD with onset of depression, only ADHD, only depression, and neither ADHD nor depression. Linear mixed effects models were used to analyse group differences in cognitive functioning at baseline and follow-up, and the change in cognitive functioning between these 2 time-points. Results showed a significant main effect of group on response time variability at baseline, working memory maintenance at follow up, and change in response time variability scores between baseline and follow-up. As compared to the healthy and depressed-only groups, adolescents with only ADHD showed longer response time variability at baseline and, which declined between baseline and follow-up. Adolescents with ADHD plus depression showed higher reaction time for working memory maintenance than the depressed only and healthy groups at follow-up. In conclusion, adolescents with self-reported ADHD show poorer cognitive functioning than healthy adolescents and those with only depression. Amongst adolescents with ADHD, specific cognitive domains show poor functioning depending on the presence or absence of comorbid depression. While adolescents with only ADHD have lower reaction time variability, those with comorbid depression have poorer working memory maintenance.

Assessment of ADHD Symptoms and the Issue of Cultural Variation: Are Conners 3 Rating Scales Applicable to Children and Parents With Migration Background?

OBJECTIVE

The objective was to evaluate whether Conners 3 ( Conners 3rd edition) ratings of ADHD symptoms are robust to distortion by cultural variation when applied to children with migration background living in Germany.

METHOD

From 2010 to 2011, Conners 3 data (self-rating, parent rating, and teacher rating) of 243 children with Turkish migration background, aged 6 to 16 years, were collected in various German schools. Allocation of items to latent factors was tested with confirmatory analyses. Reliability and validity of resulting factors was calculated and influence of acculturation, gender, and age on rating-modalities was examined.

RESULTS

Confirmatory factor analyses showed high model fits for all rating-modalities. Resulting scales had good reliability and validity. There was a small influence of acculturation on parent ratings of oppositional defiant disorder but not on ADHD core symptoms.

CONCLUSION

Conners 3 ratings seem to be robust against influences of cultural variation. Their German translation can be utilized for children with Turkish migration background without limitation.

Executive Functioning in Subtypes of Attention Deficit Hyperactivity Disorder

INTRODUCTION

This study aims to evaluate executive functions (EF), such as inhibition, planning, working memory, and set shifting, in children with attention deficit hyperactivity disorder (ADHD) by comparing three ADHD subtype groups (ADHD-Inattentive, ADHD-Combined, and ADHD-Comorbid) and a normal control group.

METHODS

Participants included 147 children. In total, 111 children were assigned to the ADHD groups of the study. Each child was matched according to the WISC-R Full-Scale IQ-score, sex, and age and was grouped as follows: ADHD-Inattentive group (ADHD-I; n=37), ADHD-Combined (ADHD-C; n=37), ADHD-Comorbid group (ADHD-Comorbid with oppositional defiant disorder and/or conduct disorder; n=37), and control group (n=36). The tests used to assess the children were Conners' Parent and Teacher Rating Scales; Wechsler Intelligence Scale-Revised; Tower of London test; Wisconsin Card Sorting Test; Stroop Color-Word Test, and verbal fluency test. The data were analyzed by one-way ANOVA between subjects for all dependent variables.

RESULTS

Children in the ADHD-I group had significantly better performances in verbal working memory and verbal category shifting than children in the ADHD-C group. There was no significant difference between the ADHD-I and ADHD-C groups in terms of inhibition, set shifting, verbal fluency, cognitive flexibility, and planning. The ADHD-Comorbid group displayed more severe impairments in EF measures than the ADHD-C group; however, the severity was not statistically significant. EF performances of children in the control group were similar to children in the ADHD-I group but better than children in the ADHD-C and ADHD-Comorbid groups.

CONCLUSION

The outcome of the study indicated that subjects in the ADHD-Comorbid and ADHD-C groups had more severe EF deficits than subjects in the ADHD-I and control groups.

Procedural learning and automatization process in children with developmental coordination disorder and/or developmental dyslexia

OBJECTIVE

There is increasing evidence to suggest that developmental dyslexia (DD) and developmental coordination disorder (DCD) actually form part of a broader disorder. Their frequent association could be justified by a deficit of the procedural memory system, that subtends many of the cognitive, motor and linguistic abilities that are impaired in both DD and DCD. However, studies of procedural learning in these two disorders have yielded divergent results, and in any case no studies have so far addressed the issue of automatization (dual-task paradigm).

METHODS

We administered a finger tapping task to participants aged 8-12 years (19 DCD, 18 DD, and 22 with both DD and DCD) to explore procedural learning and automatic movements in these three groups of children, comparing motor performances at the prelearning stage, after 2 weeks of training, and in a post-training dual-task condition.

RESULTS

First, results indicated that all the children were able to learn a sequence of movements and even automatize their movements. Second, they revealed between-groups differences in procedural/automatization learning abilities, setting the DCD group apart from the other two. Third, contrary to our expectations concerning comorbidity, they suggested that the DD+DCD association does not have an additional impact on behavioral performances.

Association of anxiety and ODD/CD in children with and without ADHD

The goal of this study is to examine levels of oppositional defiant disorder (ODD) and conduct disorder (CD) in four groups of children: attention-deficit/hyperactivity disorder (ADHD) only, anxiety only, ADHD and anxiety, and controls (i.e., non-ADHD youth). Although children with ADHD exhibit more ODD and CD than non-ADHD youth, it is unknown if anxiety is associated with increased or decreased ODD and CD in children with ADHD. We examined parent and teacher ratings of ODD and CD from the Disruptive Behavior Disorder Rating Scale in 203 school age children (ages 6-9); 70% were male, and 47% were Caucasian. Children were divided into four diagnostic groups based on ADHD and anxiety status from the Diagnostic Interview Scale for Children. According to parents, children with ADHD and anxiety had the highest levels of ODD/CD, followed by children with ADHD only (i.e., without anxiety). Children with anxiety only and controls had lowest ODD and CD scores, and these groups did not differ from each other. The same patterns were found according to teacher report, except that the anxiety only group had significantly lower levels of ODD than non-ADHD controls. Further, combined type ADHD youth with anxiety exhibited the highest levels of ODD and CD compared to all other groups. Comorbid anxiety may strengthen the association of ADHD and ODD/CD, particularly in the combined subtype. We discuss the importance of comorbid anxiety to the development of externalizing problems as well as potential explanatory factors underlying elevated ODD and CD among children with ADHD and anxiety.

Coexisting disorders and academic achievement among children with ADHD

OBJECTIVE

ADHD is a commonly diagnosed neuropsychological disorder among school-aged children with reported high rates of coexisting or comorbid disorders. As ADHD has been associated with academic underachievement, the current study examines this association in view of the presence of coexisting disorders. The purpose of the current study is to examine the relationship between the presence of coexisting disorders and academic achievement among children with ADHD using a large, nationally representative, and community-based sample.

METHOD

To achieve this purpose, the presence of coexisting disorders with ADHD and academic achievement are examined across time utilizing latent growth models.

RESULTS

Our results indicate an inverse relationship between the presence of coexisting disorders and academic achievement across time among children diagnosed with ADHD.

CONCLUSION

The authors conclude that practitioners must be concerned with the presence of coexisting disorders for children with ADHD with respect to academic achievement as well as other behavioral and psychological outcomes.

Assessment of developmental coordination disorder in children born with extremely low birth weights

There is no tool that is considered the "gold" standard for identifying children with developmental coordination disorder (DCD) and various techniques have been reported in the research literature. The aim of this study was to examine the prevalence of DCD in a cohort of extremely low birth weight (ELBW; birth weight ≤ 1,000g) children at age 5 years using various methods including standardized motor assessment measures, an established clinic protocol, and a parent report. We also examined the association between selected neonatal risk factors and severity of the motor impairment. Four methods were used to assess motor functioning: (1) the Movement Assessment Battery for Children (Movement ABC); (2) a motor assessment battery, which included the Movement ABC, the Beery-Buktenica Developmental Test of Visual Motor Integration, and the Developmental Test of Visual Perception-2; (3) a Perinatal Follow-up Clinic protocol, which included the Geometric Design and the Mazes subtests of the Wechsler Preschool and Primary Scale of Intelligence-Revised, the Fine and Gross Motor subscales of the Child Development Inventory, and a pediatric neuromotor exam; and (4) a parent completed questionnaire (i.e., Developmental Coordination Disorder Questionnaire (DCDQ)). The prevalence of motor impairment in ELBW children was 64% on the Movement ABC, 67% on the motor assessment battery, 66% on the Perinatal Follow-up Clinic protocol, and 26% on the DCDQ. Sensitivity ranged from 36% to 100% and specificity from 65% to 92% using the Movement ABC as the reference standard. Neonatal risk factors associated with increased severity of motor impairment were bronchopulmonary dysplasia, postnatal steroids, and increasing gestational age. Children with birth weights ≤ 1,000 g are at considerable risk for motor impairment; therefore, developmental evaluations should include an assessment of motor functions. A standardized motor assessment test such as the Movement ABC appears to be the most effective and efficient means of identifying motor impairment in this high-risk population.

Psychosocial factors associated with parent and teacher reports of aggression in children and adolescents with attention deficit hyperactivity disorder

OBJECTIVE

The prognosis for individuals diagnosed with attention deficit hyperactivity disorder (ADHD) and comorbid aggression is substantially worse than for those with ADHD alone. This study investigates the contribution of key psychosocial factors to both parent and teacher reports of aggressive behaviour in children and adolescents diagnosed with ADHD. It was hypothesized that greater impairment in each would be associated with higher levels of both parent-rated and teacher-rated aggression.

METHOD

Information collected during semi-structured clinical interviews from 676 boys and girls aged 6 to 16 and diagnosed with ADHD was analysed. Measures of potential psychosocial factors including parental psychopathology, family functioning, marital relationship quality and child interpersonal relationship status were administered. Ratings of aggression were obtained from both parents and teachers, and the association of psychosocial measures for each were separately analysed.

RESULTS

Correlation and multiple regression analyses revealed significant associations between parent-rated aggression and measures of increased parent psychopathology, decreased family function and deficient child interpersonal relationships. Teacher-rated aggression was only associated with deficient child interpersonal relationships.

CONCLUSION

The findings highlight important differences in the psychosocial factors that contribute to parent and teacher ratings of aggression in the context of ADHD. The implications of these findings for both the clinician and researcher are discussed.

The reliability and validity of the Aggregate Neurobehavioral Student Health and Educational Review parent's questionnaire (ANSER-PQ)

The internal reliability and validity of the Aggregate Neurobehavioral Student Health and Educational Review parent's questionnaire (ANSER-PQ) were evaluated. Three diagnostic groups participated: (1) attention-deficit hyperactivity disorder (ADHD; N = 100), (2) learning disability (N = 80), and (3) a combined group (N-100). The Conners' parent and teacher rating scales were completed. Seven clusters were derived as follows: conduct, anxiety, social, attention and activity, strengths, obsessive-compulsive, and distress and disruption. Internal reliability was found above 0.7 for 6 of the clusters. Concurrent validity was found highly significant for the clusters of conduct and attention and activity. Discriminant validity of these clusters was found acceptable for the attention and learning disability groups. The clusters of conduct, attention and activity, and distress and disruption were found to significantly correlate with the Conners' teacher scale. The ANSER-PQ may be employed for the assessment of children with attention or learning disabilities.

Gross motor performance and self-perceived motor competence in children with emotional, behavioural, and pervasive developmental disorders: a review

AIMS

Motor performance and self-perceived motor competence have a great impact on the psychosocial development of children in general. In this review, empirical studies of gross motor performance and self-perception of motor competence in children with emotional (depression and anxiety), behavioural, and pervasive developmental disorders are scrutinized, with the objective of identifying specific motor characteristics that may be relevant to clinical practice.

METHOD

A systematic search of studies published between 1997 and 2007 was performed using nine search engines.

RESULTS

Children in all three categories (emotional, behavioural, and pervasive developmental disorders) exhibit poor gross motor performance and problematic self-perception of motor competence, with certain indications of disorder-specific characteristics. In particular, children with emotional disorders have balance problems and self-perceived motor incompetence; children with behavioural disorders show poor ball skills and tend to overestimate their motor performance; children with pervasive developmental disorders demonstrate poor gross motor performance and self-perceived motor incompetence. As a result, children with developmental and emotional disorders are restricted in participating in games and play, which may lead to inactive lifestyles and further disruption of their psychosocial and physical development.

INTERPRETATION

Motor problems need more, to some extent disorder-specific, attention in clinical practice than has been provided to date.

Literature review: visual search by children with and without ADHD

OBJECTIVE

To summarize the literature that has employed visual search tasks to assess automatic and effortful selective visual attention in children with and without ADHD.

METHOD

Seven studies with a combined sample of 180 children with ADHD (M age = 10.9) and 193 normally developing children (M age = 10.8) are located.

RESULTS

Using a qualitative approach, the authors find no group difference in automatic search, but results are variable for effortful serial search. Using a novel, graphical approach, the authors find that the ADHD group demonstrated less efficient serial search. This overall effect is explored as a function of search display complexity. Children with ADHD search less efficiently at the lowest and highest levels of display complexity.

CONCLUSION

Children with ADHD show impairments in aspects of their effortful visual selective attention, as measured by visual search.