Joshua M. Langberg

Evidence for Higher Reaction Time Variability for Children With ADHD on a Range of Cognitive Tasks Including Reward and Event Rate Manipulations

OBJECTIVE The purpose of the research study was to examine the manifestation of variability in reaction times (RT) in children with attention deficit hyperactivity disorder (ADHD) and to examine whether RT variability presented differently across a variety of neuropsychological tasks, was present across the two most common ADHD subtypes, and whether it was affected by reward and event rate (ER) manipulations. METHOD Children with ADHD-combined type (n = 51), ADHD-predominantly inattentive type (n = 53), and 47 controls completed five neuropsychological tasks (Choice Discrimination Task, Child Attentional Network Task, Go/No-Go task, Stop Signal Task, and N-back task), each allowing trial-by-trial assessment of RTs. Multiple indicators of RT variability including RT standard deviation, coefficient of variation and ex-Gaussian tau were used. RESULTS Children with ADHD demonstrated greater RT variability than controls across all five tasks as measured by the ex-Gaussian indicator tau. There were minimal differences in RT variability across the ADHD subtypes. Children with ADHD also had poorer task accuracy than controls across all tasks except the Choice Discrimination task. Although ER and reward manipulations did affect childrens RT variability and task accuracy, these manipulations largely did not differentially affect children with ADHD compared to controls. RT variability and task accuracy were highly correlated across tasks. Removing variance attributable to RT variability from task accuracy did not appreciably affect between-groups differences in task accuracy. CONCLUSIONS High RT variability is a ubiquitous and robust phenomenon in children with ADHD.

The Transition to Middle School is Associated with Changes in the Developmental Trajectory of ADHD Symptomatology in Young Adolescents with ADHD

The attention deficit hyperactivity disorder (ADHD) symptom presentation of young adolescents with ADHD was examined in association with the transition to middle school. This study used data collected in the Multimodal Treatment Study of ADHD, which included children between 7 and 9 years of age with a diagnosis of ADHD (n = 258) and grade- and sex-matched controls (n = 112). The trajectory of ADHD symptoms before, during, and after the transition to middle school was modeled using hierarchical linear modeling. A clear developmental reduction in ADHD symptomatology was observed for all three ADHD symptom domains. For young adolescents with ADHD, the transition to middle school was associated with a disruption in the developmental decline of inattention, hyperactivity, and impulsivity symptoms as measured by parent ratings. This effect was also observed for teacher ratings of inattention and hyperactivity. These results support the assertion that the environmental changes associated with transitioning to middle school coincide with a transient reversal in ADHD symptom decline among children with ADHD.

Sluggish Cognitive Tempo Among Young Adolescents With ADHD: Relations to Mental Health, Academic, and Social Functioning

Objective: This study investigated the role of sluggish cognitive tempo (SCT) in relation to externalizing and internalizing mental health problems, academic functioning, and social functioning among young adolescents with attention-deficit/hyperactivity disorder (ADHD). Method: In all, 57 youth ages 10 to 14 participated in the study. Parents rated SCT, internalizing, and externalizing symptoms, as well as social and academic impairment. Teachers rated academic and peer impairment, and intelligence and academic achievement also were assessed. Results: Above and beyond ADHD and conduct problem symptoms, SCT was associated with internalizing mental health symptoms and social problems. The association between SCT and externalizing problems or academic functioning was not significant when accounting for ADHD symptomatology and intelligence. Conclusion: SCT is consistently associated with internalizing symptoms and is also associated with young adolescents’ general social difficulties. When controlling for important related constructs, SCT is not associated with externalizing symptoms or academic impairment among young adolescents with ADHD.

Co-occurring mental health problems and peer functioning among youth with attention-deficit/hyperactivity disorder: a review and recommendations for future research.

It is well established that children and adolescents with attention-deficit/hyperactivity disorder (ADHD) frequently experience co-occurring mental health problems in addition to difficulties in their peer relationships. Although substantial research has focused on the extent to which peer functioning contributes to subsequent co-occurring mental health problems, much less research has considered how co-occurring mental health problems affect peer functioning domains. Therefore, the purpose of this review is to examine the effect of co-occurring mental health problems on the peer functioning of youth with ADHD. The impact of co-occurring externalizing (i.e., oppositional defiant disorder, conduct disorder) and internalizing (i.e., anxiety, depression) symptoms are reviewed, with a focus on whether these co-occurring symptoms exacerbate, attenuate, or have no effect across peer domains of social skills/competence, peer status, and friendship among youth with ADHD. Drawing from a developmental psychopathology framework, this review then draws attention to relevant causal processes and developmental cascades (including social-cognitive, affective, and family and parenting factors) in offering promising avenues for future work.

Patterns and Predictors of Adolescent Academic Achievement and Performance in a Sample of Children with Attention-Deficit/Hyperactivity Disorder

The current study examined predictors of academic achievement, measured by standardized test scores, and performance, measured by school grades, in adolescents (Mn age = 16.8) who met diagnostic criteria for Attention-Deficit/Hyperactivity Disorder (ADHD)–Combined type in early childhood (Mn age = 8.5; N = 579). Several mediation models were also tested to determine whether ADHD medication use, receipt of special education services, classroom performance, homework completion, or homework management mediated the relationship between symptoms of ADHD and academic outcomes. Childhood predictors of adolescent achievement differed from those for performance. Classroom performance and homework management mediated the relationship between symptoms of inattention and academic outcomes.

Community-wide Intervention to Improve the Attention-Deficit/Hyperactivity Disorder Assessment and Treatment Practices of Community Physicians

OBJECTIVES. The goals were to implement and to test a quality-improvement intervention aimed at improving community-based primary care providers’ adherence to the American Academy of Pediatrics, evidence-based diagnostic and treatment guidelines for attention-deficit/hyperactivity disorder. METHODS. Nineteen practices (with 84 primary care providers) from a large urban community were trained by using quality-improvement methods with some academic detailing. Pretraining and posttraining adherence to evidence-based practices was assessed through review of patient charts. RESULTS. Preintervention rates of guideline usage were uniformly low. After the intervention, primary care providers showed substantial improvement in their use of the guidelines for the assessment and treatment of elementary school-aged patients with newly diagnosed attention-deficit/hyperactivity disorder. Use of parent and teacher assessment rating scales increased from levels of 52% to 55% to levels of nearly 100%. Systematic monitoring of responses to medication improved from a baseline level of 9% to 40%. CONCLUSIONS. Quality-improvement interventions such as the one used in this study seem quite effective in improving primary care providers’ practices at offices that express interest in improving the quality of care for attention-deficit/hyperactivity disorder. The design of the intervention, problems associated with improving and sustaining treatment monitoring, and issues related to generalizability of the intervention model are discussed.

Parent Agreement on Ratings of Children's Attention Deficit/Hyperactivity Disorder and Broadband Externalizing Behaviors.

Mothers and fathers often disagree in their ratings of child behavior, as evidenced clinically and as supported by a substantial literature examining parental agreement on broadband rating scales. The present study examined mother—father agreement on Diagnostic and Statistical Manual—based symptom-specific ratings of Attention-Deficit/Hyperactivity Disorder (ADHD), as compared to agreement on broadband ratings of externalizing behavior. Based on mother and father ratings of 324 children who participated in the Multimodal Treatment Study of Children with ADHD (MTA), parental agreement was computed and patterns of disagreement examined. Mother—father ratings were significantly correlated; however, a clear pattern of higher ratings by mothers was present. Agreement on attention-deficit/hyperactivity disorder symptom-specific ratings was significantly lower than that for broadband externalizing behaviors and oppositional defiant disorder symptoms. Of several moderator variables tested, parental stress was the only one that predicted the discrepancy in ratings. Disagreement between parents is clinically significant and may pose complications to the diagnostic process.Mothers and fathers often disagree in their ratings of child behavior as evidenced clinically and supported by a substantial literature examining parental agreement on broadband rating scales. The present study examined mother-father agreement on DSM-based, ADHD symptom-specific ratings, as compared to agreement on broadband ratings of externalizing behavior. Using mother and father ratings from 324 children who participated in the Multimodal Treatment Study of Children with ADHD, parental agreement was computed and patterns of disagreement were examined. Mother-father ratings were significantly correlated. However, a clear pattern of higher ratings by mothers compared to fathers was present across ratings. Agreement on ADHD symptom-specific ratings was significantly lower than agreement for broadband externalizing behaviors or ODD symptoms. Of several moderator variables tested, parental stress was the only variable that predicted the discrepancy in ratings. Disagreement between parents is clinically significant and may pose complications to the diagnostic process.

Parent-Reported Homework Problems in the MTA Study: Evidence for Sustained Improvement with Behavioral Treatment

Parent-report of child homework problems was examined as a treatment outcome variable in the MTA–Multimodal Treatment Study of Children with Attention-Deficit/Hyperactivity Disorder (ADHD). Five hundred seventy-nine children ages 7.0 to 9.9 were randomly assigned to either medication management, behavioral treatment, combination treatment, or routine community care. Results showed that only participants who received behavioral treatment (behavioral and combined treatment) demonstrated sustained improvements in homework problems in comparison to routine community care. The magnitude of the sustained effect at the 10-month follow-up assessment was small to moderate for combined and behavioral treatment over routine community care (d = .37, .40, respectively). Parent ratings of initial ADHD symptom severity was the only variable found to moderate these effects.

Attention-Deficit/Hyperactivity Disorder Outcomes for Children Treated in Community-Based Pediatric Settings

OBJECTIVE To determine if children treated by community physicians who participated in an attention-deficit/hyperactivity disorder (ADHD) quality improvement intervention demonstrate symptom and impairment improvements comparable with those achieved in university-based clinical trials. DESIGN Case series. SETTING Rural, suburban, and urban practices, with 28% of the 47 practices serving primarily (>50% of patients) Medicaid-receiving populations. PARTICIPANTS A total of 785 children aged between 7 and 11 years were treated for ADHD by community physicians participating in the study. Intervention A total of 158 community physicians from 47 separate practices participated in a quality improvement intervention, the ADHD Collaborative, designed to improve physician adherence to evidence-based ADHD treatment guidelines. The intervention included mapping and redesign of practice office flow to facilitate adherence to American Academy of Pediatrics ADHD guidelines as well as didactic sessions related to diagnosis and treatment of ADHD. Medical record reviews were completed at the initial assessment and every 3 months for 1 year to evaluate treatment outcome. OUTCOME MEASURES Improvement in parent- and teacher-rated ADHD symptoms and functional impairment. RESULTS Children showed large improvements in parent- and teacher-rated ADHD symptoms, similar to some clinical trials, but made no significant improvements in functional impairment. CONCLUSIONS Large improvements in ADHD symptoms can be achieved in primary care settings when physicians provide evidence-based ADHD care using medication. Because many children with ADHD continued to have significant functional impairment despite symptom improvement, collaboration with other mental health or educational services in additional to medication appears warranted.

Effects of Stimulant Medication, Incentives, and Event Rate on Reaction Time Variability in Children With ADHD

This study examined the effects of methylphenidate (MPH) on reaction time (RT) variability in children with attention deficit hyperactivity disorder (ADHD). Using a broad battery of computerized tasks, and both conventional and ex-Gaussian indicators of RT variability, in addition to within-task manipulations of incentive and event rate (ER), this study comprehensively examined the breadth, specificity, and possible moderators of effects of MPH on RT variability. A total of 93 children with ADHD completed a 4-week within-subject, randomized, double-blind, placebo-controlled crossover trial of MPH to identify an optimal dosage. Children were then randomly assigned to receive either their optimal MPH dose or placebo after which they completed five neuropsychological tasks, each allowing trial-by-trial assessment of RTs. Stimulant effects on RT variability were observed on both measures of the total RT distribution (ie, coefficient of variation) as well as on an ex-Gaussian measure examining the exponential portion of the RT distribution (ie, τ). There was minimal, if any, effect of MPH on performance accuracy or RT speed. Within-task incentive and ER manipulations did not appreciably affect stimulant effects across the tasks. The pattern of significant and pervasive effects of MPH on RT variability, and few effects of MPH on accuracy and RT speed suggest that MPH primarily affects RT variability. Given the magnitude and breadth of effects of MPH on RT variability as well as the apparent specificity of these effects of MPH on RT variability indicators, future research should focus on neurophysiological correlates of effects of MPH on RT variability in an effort to better define MPH pharmacodynamics.