Do Preschoolers' Neuropsychological Functioning and Hyperactivity/Inattention Predict Social Functioning Trajectories Through Childhood?

OBJECTIVE: This longitudinal study examined whether preschool attention deficit hyperactivity disorder (ADHD) symptoms and neuropsychological functioning predicted trajectories of children's social functioning from age 3 to 4 through 12 years. METHODS: Three- and four-year-old children (N = 208; 72.6% boys) were evaluated annually through age 12. Parent and teacher Attention Deficit/Hyperactivity Disorder Rating Scale, Fourth Edition responses during the initial evaluation were used to categorize preschoolers as "High" or "Low" risk for ADHD. Children's neuropsychological functioning was assessed using the NEPSY. Teachers' reports of children's social functioning were obtained annually from preschool through age 12 years using the Adaptability, Functional Communication, and Social Skills subscales of the Behavioral Assessment System for Children, Second Edition. Hierarchical linear modeling was used to assess the trajectories of social functioning and determine whether preschoolers' neuropsychological functioning and ADHD risk status predicted social functioning at age 12 years, and/or change in social functioning throughout childhood. All models controlled for baseline socioeconomic status. RESULTS: High Risk children had significantly lower teacher-rated Adaptability and Social Skills at age 12 years. High Risk children and those with lower Verbal neuropsychological functioning in preschool had lower teacher-rated Functional Communication at 12 years old. Lower preschool Verbal neuropsychological functioning predicted greater positive change in teacher-rated Functional Communication across childhood. CONCLUSIONS: Early identification of and intervention for children exhibiting ADHD behaviors is critical given the enduring negative impact of these behaviors on social functioning. Screening preschoolers for verbal difficulties is encouraged given their long-term impact on children's ability to clearly express thoughts and feelings and obtain and provide information.

Practitioner Review: Assessment and treatment of preschool children with attention-deficit/hyperactivity disorder.

BACKGROUND: Attention-deficit/hyperactivity disorder (ADHD) often emerges during the preschool years and remains impairing throughout the life span. Early identification and intervention may yield lasting benefits that alter the often-adverse trajectory of the disorder. METHODS: This Practitioner Review provides up-to-date information regarding the evaluation and treatment of ADHD in preschool children. The clinical presentation of ADHD in preschool children, its persistence into later childhood, the applicability of DSM-5 criteria for preschoolers with ADHD, and early predictors of long-term trajectories are addressed, as well as current findings from randomized controlled trials of both nonpharmacological and pharmacological interventions. RESULTS: Symptoms of hyperactivity/impulsivity extend down to age 3, but several inattention symptoms, as defined by DSM-V, less accurately differentiate preschoolers with and without ADHD. Most preschool youth with ADHD symptoms continue to manifest symptoms and impairment into school-age and adolescence. However, few predictors of persistence beyond early severity have been identified. Behavioral interventions constitute a first-line treatment for preschool ADHD symptoms, with telepsychiatry increasing in prominence to help to mitigate financial, geographic, and/or logistical barriers to care. Pharmacological interventions, particularly psychostimulants, also confer demonstrable benefits, yet efficacy and safety profiles are less desirable relative to findings in school-age youth. CONCLUSIONS: Acute treatments have demonstrable efficacy, but do not appear to fundamentally alter underlying mechanisms or long-term trajectories.

Generating Attention, Inhibition, and Memory: A Pilot Randomized Trial for Preschoolers With Executive Functioning Deficits.

This goal of this study was to assess the initial feasibility and efficacy of a play-based intervention targeting executive functions (EF) and parent-child relationships in preschoolers compared with an active control group. Preschoolers with EF deficits (M age = 3.7 ± 0.47, predominantly White boys) and their parents were randomized to intervention (n = 36) or active control (n = 32) conditions. Child performance on EF tasks, parent and masked teacher ratings of EF and behavior, and masked clinician ratings of severity were collected at baseline and at 3 and 6 months postbaseline. Partial eta-squared effect sizes at .02 or higher comparing performance across the two groups was considered evidence of meaningful, albeit small, intervention effects. Intervention effects were observed for parent ratings of inattention, hyperactivity/impulsivity, and number/severity of problems experienced in various home situations, teacher ratings of severity of problems in various school situations, parent and teacher ratings of overall impairment, and clinician ratings of impairment. Intervention effects for functional improvements were maintained at the 6-month follow-up. No effect of the intervention was observed on the objective EF measures, although parent ratings of emotional control were improved for children in the intervention group. An intervention utilizing play-based activities targeting EF, when administered in a structured way by parents, is a promising approach for improving behavior in preschoolers with self-regulation deficits. More work is needed to investigate potential impact on EF and to disentangle mechanisms of action. It may be that the intervention's focus on the structure and quality of parent-child interactions is a mediator of outcomes, rather than improved EFs.

Editorial: Troubled trajectories - new insights on risk pathways and developmental phenotypes of ADHD and externalizing problems.

We are pleased to present this special issue of JCPP, which brings together a collection of cutting-edge empirical studies that focuses on developmental trajectories and pathways associated with ADHD, conduct problems and other externalizing behaviors. JCPP has had a long-standing focus on theoretically strong prospective longitudinal studies that elucidate behavioral change and outcomes over time, including in the areas of ADHD and externalizing disorders (Kuja-Halkola, Lichtenstein, D'Onofrio & Larsson, 2015; Sonuga-Barke & Halperin, 2010). Keeping with that tradition, all of the papers in this special issue employ a prospective longitudinal design and a focus on changes that unfold over development.

Developmental psychopathology in the post-genomics era - substantial challenges but reasons for hope.

One only has to quickly look through the Table of Contents for this issue of JCPP to gain an appreciation of the ever-increasing influence of genetic research in the field of developmental psychopathology. Among the 13 articles in this issue that follow this editorial: two employ large family and/or twin studies to provide compelling behavioral genetic findings bolstering the importance of genes in the emergence of ADHD (Chen, Brikell, Lichtenstein, Serlachius, Kuja-Halkola, Sandin, and Larsson) and level of educational achievement in adolescents (Lewis, Asbury, and Plomin); one paper focuses on cortical development in patients with 22q11.2 deletion syndrome and its association with positive symptoms of psychosis (Radoeva, Bansal, Antshel, Fremont, Peterson, and Kates); a Commentary (Border and Keller) and Response to Commentary (Moore) debate the relative advantages and disadvantages of candidate gene versus genome-wide approaches to detecting certain genetic markers, particularly in relation to interactions with the environment; and two more focus on the identification of endophenotypes for autism spectrum disorders which will presumably facilitate the identification of genes for this complex disorder (Jones, Venema, Earl, Lowy, and Webb; Van Eylen, Boets, Cosemans, Peeters, Steyaert, Wagemans, and Noens).

Preschool Predictors of ADHD Symptoms and Impairment During Childhood and Adolescence.

PURPOSE OF REVIEW: This paper summarizes key, recently published research examining longitudinal outcomes for preschoolers with high levels of inattention and/or hyperactivity/impulsivity. RECENT FINDINGS: Symptom trajectories show that hyperactivity/impulsivity declines across childhood. At the group level, the course of inattention appears more variable. However, identification of subgroups of children showing stable, rising, and falling inattention over time is promising. Early ADHD-like symptoms portend risk for academic and social difficulties, as well as comorbid emotional and behavioral problems in childhood and adolescence. Several early risk factors appear to moderate these relations, including comorbid symptoms, parental psychopathology, socioeconomic disadvantage, and perhaps neuropsychological dysfunction. Furthermore, high levels of inattention and/or hyperactivity/impulsivity during the preschool period appear to compromise development of regulatory and neuropsychological functions, which in turn increases risk for negative outcomes later in childhood. Identified risk factors are targets for novel interventions, which ideally would be delivered early to at-risk children.

Executive functioning - a key construct for understanding developmental psychopathology or a 'catch-all' term in need of some rethinking?

For the past few decades, the role of executive functions in developmental psychopathology has been the focus of considerable research and a feature of conceptual models for a range of conditions including, but not limited to, ADHD, autism, schizophrenia, bipolar disorder, learning disorders, and aggression/conduct problems. Consistent with its prominence throughout the field, executive functioning plays a central role in approximately a third of the papers in this issue of JCPP, and notably, with foci largely on different conditions. These papers, all of which make valuable contributions to the field, propose or test the possibility of a causal role for executive functions in the emergence of psychopathology.

Parenting style influences bullying: a longitudinal study comparing children with and without behavioral problems.

BACKGROUND: More optimal parenting has been linked with lower rates of bullying. However, it is not clear whether parenting can alter the trajectories of bullying among children diagnosed with ADHD or ODD as well as those who are not so diagnosed. This study examined whether parenting at age 4-5 years was associated with changes in bullying over the next 4 years among children with Attention-deficit/Hyperactivity Disorder (ADHD) with and without comorbid Oppositional Defiant Disorder (ODD) relative to children without these disorders. METHOD: Children from the New York metropolitan area (n = 162) were prospectively studied over six annual assessment points between preschool and 9 years of age. Parenting was assessed by laboratory observations of the parent and child; teachers rated child bullying, and parents reported on children's diagnostic status (Neither ADHD nor ODD, ADHD but not ODD, both ADHD and ODD). RESULTS: Children with comorbid ADHD and ODD were more likely to bully than the other two groups. Hierarchical linear modeling revealed a fall in bullying over five years. Diagnostic status was significantly associated with initial levels of bullying. Irrespective of diagnostic group, children receiving more parent support for child autonomy at age 4 to 5 years showed a significantly greater decline in bullying than those provided with little support for autonomy. There was no longitudinal link between parent negative affect, emotionally supportive parenting and quality of parent-child interactions with bullying. CONCLUSIONS: Greater parent support for child autonomy at age 4-5 years is related to reduced bullying. Interventions that encourage parent support for child autonomy at the time of entry into school may reduce bullying during early school years.

Good Holders, Bad Shufflers: An Examination of Working Memory Processes and Modalities in Children with and without Attention-Deficit/Hyperactivity Disorder.

The aim of this study was to examine working memory (WM) modalities (visual-spatial and auditory-verbal) and processes (maintenance and manipulation) in children with and without attention-deficit/hyperactivity disorder (ADHD). The sample consisted of 63 8-year-old children with ADHD and an age- and sex-matched non-ADHD comparison group (N=51). Auditory-verbal and visual-spatial WM were assessed using the Digit Span and Spatial Span subtests from the Wechsler Intelligence Scale for Children Integrated - Fourth Edition. WM maintenance and manipulation were assessed via forward and backward span indices, respectively. Data were analyzed using a 3-way Group (ADHD vs. non-ADHD)×Modality (Auditory-Verbal vs. Visual-Spatial)×Condition (Forward vs. Backward) Analysis of Variance (ANOVA). Secondary analyses examined differences between Combined and Predominantly Inattentive ADHD presentations. Significant Group×Condition (p=.02) and Group×Modality (p=.03) interactions indicated differentially poorer performance by those with ADHD on backward relative to forward and visual-spatial relative to auditory-verbal tasks, respectively. The 3-way interaction was not significant. Analyses targeting ADHD presentations yielded a significant Group×Condition interaction (p=.009) such that children with ADHD-Predominantly Inattentive Presentation performed differentially poorer on backward relative to forward tasks compared to the children with ADHD-Combined Presentation. Findings indicate a specific pattern of WM weaknesses (i.e., WM manipulation and visual-spatial tasks) for children with ADHD. Furthermore, differential patterns of WM performance were found for children with ADHD-Predominantly Inattentive versus Combined Presentations. (JINS, 2016, 22, 1-11).

Latent profile analysis of neuropsychological measures to determine preschoolers' risk for ADHD.

BACKGROUND: Hyperactive/Inattentive preschool children show clear evidence of neuropsychological dysfunction. We examined whether patterns and severity of test scores could reliably identify subgroups of preschoolers with differential risk for ADHD during school-age. METHOD: Typically developing (TD: n = 76) and Hyperactive/Inattentive (HI: n = 138) 3-4 year olds were assessed annually for 6 years (T1-T6). Latent profile analysis (LPA) was used to form subgroups among the HI group based on objective/neuropsychological measures (NEPSY, Actigraph and Continuous Performance Test). Logistic regression assessed the predictive validity of empirically formed subgroups at risk for ADHD diagnosis relative to the TD group and to each other from T2 to T6. RESULTS: Latent profile analysis yielded two subgroups of HI preschoolers: (a) selectively weak Attention/Executive functions, and (b) pervasive neuropsychological dysfunction across all measures. Both subgroups were more likely to have ADHD at all follow-up time-points relative to the TD group (OR range: 11.29-86.32), but there were no significant differences between the LPA-formed subgroups of HI children at any time-point. CONCLUSIONS: Objective/neuropsychological measures distinguish HI preschoolers from their TD peers, but patterns and severity of neuropsychological dysfunction do not predict risk for ADHD during school-age. We hypothesize that trajectories in at-risk children are influenced by subsequent environmental and neurodevelopmental factors, raising the possibility that they are amenable to early intervention.

Differential impact of methylphenidate and atomoxetine on sustained attention in youth with attention-deficit/hyperactivity disorder.

BACKGROUND: This study examined the effects of atomoxetine (ATX) and OROS methylphenidate (MPH) on laboratory measures of inhibitory control and attention in youth with attention-deficit/hyperactivity disorder (ADHD). It was hypothesized that performance would be improved by both treatments, but response profiles would differ because the medications work via different mechanisms. METHODS: One hundred and two youth (77 male; mean age = 10.5 ± 2.7 years) with ADHD received ATX (1.4 ± 0.5 mg/kg) and MPH (52.4 ± 16.6 mg) in a randomized, double-blind, crossover design. Medication was titrated in 4-6-week blocks separated by a 2-week placebo washout. Inhibitory control and attention measures were obtained at baseline, following washout, and at the end of each treatment using Conners' Continuous Performance Test II (CPT-II), which provided age-adjusted T-scores for reaction time (RT), reaction time variability (RT variability), and errors. Repeated-measures analyses of variance were performed, with Time (premedication, postmedication) and Treatment type (ATX, MPH) entered as within-subject factors. Data from the two treatment blocks were checked for order effects and combined if order effects were not present. CLINICAL TRIAL REGISTRATION: Clinicaltrials.gov: NCT00183391. RESULTS: Main effects for Time on RT (p = .03), RTSD (p = .001), and omission errors (p = .01) were significant. A significant Drug × Time interaction indicated that MPH improved RT, RTSD, and omission errors more than ATX (p < .05). Changes in performance with treatment did not correlate with changes in ADHD symptoms. CONCLUSIONS: MPH has greater effects than ATX on CPT measures of sustained attention in youth with ADHD. However, the dissociation of cognitive and behavioral change with treatment indicates that CPT measures cannot be considered proxies for symptomatic improvement. Further research on the dissociation of cognitive and behavioral endpoints for ADHD is indicated.

Associations between birth weight and attention-deficit/hyperactivity disorder symptom severity: indirect effects via primary neuropsychological functions.

BACKGROUND: Attention-deficit/hyperactivity disorder (ADHD) has a range of aetiological origins which are associated with a number of disruptions in neuropsychological functioning. This study aimed to examine how low birth weight, a proxy measure for a range of environmental complications during gestation, predicted ADHD symptom severity in preschool-aged children indirectly via neuropsychological functioning. METHODS: A total of 197 preschool-aged children were recruited as part of a larger longitudinal study. Two neuropsychological factors were derived from NEPSY domain scores. One, referred to as 'Primary Neuropsychological Function,' was loaded highly with Sensorimotor and Visuospatial scores. The other, termed 'Higher-Order Function' was loaded highly with Language and Memory domain scores. Executive functioning split evenly across the two. Analyses examined whether these neuropsychological factors allowed for an indirect association between birth weight and ADHD symptom severity. RESULTS: As both factors were associated with symptom severity, only the Primary Neuropsychological Factor was associated with birth weight. Furthermore, birth weight was indirectly associated to symptom severity via this factor. CONCLUSIONS: These data indicate that birth weight is indirectly associated with ADHD severity via disruption of neuropsychological functions that are more primary in function as opposed to functions that play a higher-order role in utilising and integrating the primary functions.

Moderator effects of working memory on the stability of ADHD symptoms by dopamine receptor gene polymorphisms during development.

We tested the hypothesis that dopamine D1 and D2 receptor gene (DRD1 and DRD2, respectively) polymorphisms and the development of working memory skills can interact to influence symptom change over 10 years in children with attention-deficit/hyperactivity disorder (ADHD). Specifically, we examined whether improvements in working memory maintenance and manipulation from childhood to early adulthood predicted the reduction of ADHD symptoms as a function of allelic variation in DRD1 and DRD2. Participants were 76 7-11-year-old children with ADHD who were genotyped and prospectively followed for almost 10 years. ADHD symptoms were rated using the Attention Problems scale on the Child Behavior Checklist, and verbal working memory maintenance and manipulation, measured by Digit Span forward and backward, respectively, were assessed at baseline and follow-up. After correction for multiple testing, improvements in working memory manipulation, not maintenance, predicted reduction of symptomatology over development and was moderated by major allele homozygosity in two DRD1 polymorphisms (rs4532 and rs265978) previously linked with variation in D1 receptor expression. Depending on genetic background, developmental factors including age-dependent variation in DRD1 penetrance may facilitate the link between improvements in higher-order working memory and the remission of symptoms in individuals with childhood-diagnosed ADHD. Furthermore, the current findings suggest that DRD1 might contribute minimally to the emergence of symptoms and cognitive difficulties associated with ADHD in childhood, but may act as a modifier gene of these clinical features and outcome during later development for those with ADHD.

One-week temporal stability of hyperactivity in preschoolers with ADHD during psychometric assessment.

AIM: To examine the usefulness of temporal measures of motor activity during psychometric assessment on two different assessment days, 1 week apart with a scope to help the early identification of hyperactivity. METHODS: Actigraph measures at the ankle and the waist were compared on the first and the second days of psychometric assessment in a total of 169 children (93 children in ADHD group; 76 children in Non-ADHD group) aged 3 years and 4 years. RESULTS: There was a significant interaction effect between group and time on the activity level at the waist. Although the activity level of the waist in the children with ADHD did not significantly differ between Day 1 and Day 2, the activity level of the children without ADHD declined significantly from Day 1 to 2. A total of 70% of children were correctly classified into ADHD or Non-ADHD groups based only on Day 2 waist activity data. CONCLUSION: The temporal consistency of hyperactivity in young children with ADHD during psychometric assessment is confirmed, indicating that objective measures of motor activity at the waist over different days of psychometric assessment can provide additional information for the stability of hyperactivity.

Distinct structural brain network properties in children with familial versus non-familial attention-deficit/hyperactivity disorder (ADHD).

Attention-deficit/hyperactivity disorder (ADHD) is among the most prevalent, inheritable, and heterogeneous childhood-onset neurodevelopmental disorders. Children with a hereditary background of ADHD have heightened risk of having ADHD and persistent impairment symptoms into adulthood. These facts suggest distinct familial-specific neuropathological substrates in ADHD that may exist in anatomical components subserving attention and cognitive control processing pathways during development. The objective of this study is to investigate the topological properties of the gray matter (GM) structural brain networks in children with familial ADHD (ADHD-F), non-familial ADHD (ADHD-NF), as well as matched controls. A total of 452 participants were involved, including 132, 165 and 155 in groups of ADHD-F, ADHD-NF and typically developed children, respectively. The GM structural brain network was constructed for each group using graph theoretical techniques with cortical and subcortical structures as nodes and correlations between volume of each pair of the nodes within each group as edges, while controlled for confounding factors using regression analysis. Relative to controls, children in both ADHD-F and ADHD-NF groups showed significantly higher nodal global and nodal local efficiencies in the left caudal middle frontal gyrus. Compared to controls and ADHD-NF, children with ADHD-F showed distinct structural network topological patterns associated with right precuneus (significantly higher nodal global efficiency and significantly higher nodal strength), left paracentral gyrus (significantly higher nodal strength and trend toward significantly higher nodal local efficiency) and left putamen (significantly higher nodal global efficiency and trend toward significantly higher nodal local efficiency). Our results for the first time in the field provide evidence of familial-specific structural brain network alterations in ADHD, that may contribute to distinct clinical/behavioral symptomology and developmental trajectories in children with ADHD-F.

Pragmatic deficits and social impairment in children with ADHD.

BACKGROUND: Impaired social functioning has been well documented in individuals with attention-deficit/hyperactivity disorder (ADHD). Existing treatments for ADHD are effective for managing core symptoms, but have limited effectiveness at improving social skills, suggesting that social deficits in ADHD may not be directly related to core symptoms of the disorder. Language problems are also common in ADHD, with accumulating evidence of pragmatic language difficulties. Pragmatic deficits are associated with social impairment in several neurodevelopmental disorders. This study systematically examined pragmatic language functioning in children with ADHD and whether social impairment in ADHD is mediated by pragmatic deficits. METHOD: Sixty-three children (28 ADHD; 35 typically developing), ages 7-11 years, underwent a comprehensive assessment of pragmatic language, including parent ratings, standardized tests, and a narrative task. Parents also rated children's social skills on the Social Skills Improvement System. RESULTS: Children with ADHD had poorer pragmatic language skills relative to peers across all measures, even after controlling for general language abilities. Furthermore, pragmatic abilities as measured by parent ratings, mediated the relation between ADHD and social skills. CONCLUSIONS: Pragmatic language skills are impaired in many children with ADHD and may partially account for high rates of social impairment. Implications for treatment and possible prevention of social problems in children with ADHD are discussed.

Automatic processing of duration in children with attention-deficit/hyperactivity disorder.

Individuals with attention-deficit/hyperactivity disorder (ADHD) often exhibit deficits in processing information about time. Most studies, however, have required participants to perform active tasks and consequently it is unclear if performance deficits are due to impaired processing of temporal information, attentional deficits, or to impairments at a later stage of decision-making. This study used mismatch negativity (MMN) to examine automatic processing of temporal information in children with ADHD. The sample consisted of 11 children with typical development (8 boys; mean age/SD = 9.3/0.6 years) and 12 with ADHD (10 boys; mean age/SD = 8.9/0.8 years). Using the MMN paradigm, responses to standards and four deviants (hard/easy frequency, hard/easy duration) were elicited during the same sequence. The children's ability to actively discriminate each deviant was also assessed. Both groups exhibited MMNs to all deviants suggesting successful automatic discrimination. Furthermore, amplitude and latency measures were roughly comparable across groups. No group differences were seen on the active discrimination task, but performance was worse for duration than for frequency deviants. These results suggest that children with ADHD are able to automatically process temporal information, so deficits reported in active discrimination paradigms are likely due to deficits in subjective perception or usage of temporal information.

Delinquency, aggression, and attention-related problem behaviors differentially predict adolescent substance use in individuals diagnosed with ADHD.

OBJECTIVE: To measure the degree to which childhood and adolescent ratings of aggression, attention, and delinquency are related to adolescent substance use outcomes in youth diagnosed with attention-deficit/hyperactivity disorder (ADHD). BACKGROUND: Childhood externalizing disorders have been shown to predict adolescent maladaptive substance use, but few studies have examined the differential predictive utility of two distinct dimensions of externalizing behavior: aggression and delinquency. METHODS: Ninety-seven clinically referred children with ADHD initially took part in this research protocol when they were on average 9.05 years of age, and were seen again on average 9.30 years later. Participants' parents were administered the Child Behavior Checklist (CBCL) at baseline and follow-up, and youth completed the Youth Self Report (YSR) in adolescence. At follow-up, substance use severity and diagnosis were assessed using semi-structured psychiatric interviews administered separately to parents and adolescents. Linear and binary logistic regressions were used to determine the association of CBCL- and YSR-rated attention problems, aggression, and delinquency to adolescent substance use. RESULTS: Childhood and adolescent delinquency, but not aggression, as rated by parents and youths, predicted adolescent substance use disorders and substance use severity (all p < .05). After accounting for the associations of delinquency and aggression with adolescent substance use, ratings of attention problems in childhood and adolescence were negatively associated with substance use outcome. CONCLUSIONS: Children with ADHD who exhibit high rates of delinquency are at risk for later substance use and may require targeted prevention, intervention, and follow-up services.

Are cognitive control and stimulus-driven processes differentially linked to inattention and hyperactivity in preschoolers?

Temperament and attention-deficit/hyperactivity disorder (ADHD) are both typically viewed as biologically based behavioural constructs. There is substantial overlap between ADHD symptoms and specific temperamental traits, such as effortful control, especially in young children. Recent work by Martel and colleagues ( 2009 , 2011 ) suggests that cognitive control temperamental processes are more closely related to inattention symptoms, whereas stimulus-driven temperamental processes are linked to hyperactivity-impulsivity. The present study tested a model of temperament and ADHD symptoms in typically developing preschoolers and those at risk for ADHD using structural equation modelling. Data were from larger study on ADHD in a short-term longitudinal sample with parent/teacher reports and neurocognitive testing. Participants included 214 preschool children (72.9% male) from diverse ethnic/racial backgrounds and a wide range of socioeconomic status from a large metropolitan center. Cognitive control processes, such as effortful control, but not stimulus-driven processes, are related to inattention and hyperactivity. In contrast, stimulus-driven processes, such as emotional reactivity, were related only to hyperactivity symptoms longitudinally. These results suggest that early temperament behaviours and cognitive processes may be indicators of later childhood behavioural difficulties with lasting consequences.

Working Memory-Related Neurofunctional Correlates Associated with the Frontal Lobe in Children with Familial vs. Non-Familial Attention Deficit/Hyperactivity Disorder.

Attention deficit/hyperactivity disorder (ADHD) is a neurodevelopmental disorder with high prevalence, heritability, and heterogeneity. Children with a positive family history of ADHD have a heightened risk of ADHD emergence, persistence, and executive function deficits, with the neural mechanisms having been under investigated. The objective of this study was to investigate working memory-related functional brain activation patterns in children with ADHD (with vs. without positive family histories (ADHD-F vs. ADHD-NF)) and matched typically developing children (TDC). Voxel-based and region of interest analyses were conducted on two-back task-based fMRI data of 362 subjects, including 186, 96, and 80 children in groups of TDC, ADHD-NF, and ADHD-F, respectively. Relative to TDC, both ADHD groups had significantly reduced activation in the left inferior frontal gyrus (IFG). And the ADHD-F group demonstrated a significant positive association of left IFG activation with task reaction time, a negative association of the right IFG with ADHD symptomatology, and a negative association of the IFG activation laterality index with the inattention symptom score. These results suggest that working memory-related functional alterations in bilateral IFGs may play distinct roles in ADHD-F, with the functional underdevelopment of the left IFG significantly informing the onset of ADHD symptoms. Our findings have the potential to assist in tailored diagnoses and targeted interventions in children with ADHD-F.