Effects of methylphenidate on executive functioning in attention-deficit/hyperactivity disorder across the lifespan: a meta-regression analysis

The effects of chronic administration of stimulant and non-stimulant medications on executive functions in ADHD: A systematic review and meta-analysis

Attention-Deficit/Hyperactivity Disorder (ADHD) is associated with executive function deficits that are improved with medications. However, meta-analyses of stimulant effects on cognition have mostly tested single-dose effects, and there is no meta-analysis of non-stimulant effects. This systematic review and meta-analysis tested the clinically more relevant longer-term effects of Methylphenidate (20 studies; minimum 1 week) and Atomoxetine (8 studies; minimum 3 weeks) on reaction time, attention, inhibition, and working memory, searching papers on PubMed, Embase, Ovid MEDLINE, and PsycINFO. The meta-analysis of 18 studies in 1667 subjects showed that methylphenidate was superior to placebo in all cognitive domains with small to medium effect sizes (Hedges g of 0.34-0.59). The meta-analysis of atomoxetine included 7 studies in 829 subjects and showed no effects in working memory, but superior effects in the other domains with medium to large effect sizes (Hedge's g of 0.36-0.64). Meta-regression analysis showed no drug differences on cognitive effects. The meta-analyses show for the first time that chronic Methylphenidate and Atomoxetine have comparable effects of improving executive functions in people with ADHD.

Treating Executive Function in Youth With Attention Deficit Hyperactivity Disorder: A Review of Pharmacological and Non-Pharmacological Interventions

INTRODUCTION

Executive function (EF) deficits are common in youth with ADHD and pose significant functional impairments. The extent and effect of interventions addressing EF in youth with ADHD remain unclear.

METHODS

We conducted a systematic literature review using PRISMA guidelines. Included studies were randomized controlled trials of interventions to treat EF in youth with ADHD.

RESULTS

Our search returned 136 studies representing 11,443 study participants. We identified six intervention categories: nonstimulant pharmacological (N = 3,576 participants), neurological (N = 1,935), psychological (N = 2,387), digital (N = 2,416), physiological (N = 680), and combination (N = 366). The bulk of the evidence supported pharmacological interventions as most effective in mitigating EF, followed by psychological and digital interventions.

CONCLUSION

A breadth of treatments exists for EF in youth with ADHD. Pharmacological, psychotherapeutic, and digital interventions had the most favorable, replicable outcomes. A lack of outcome standardization across studies limited treatment comparison. More data on the persistence of intervention effects are necessary.

A preliminary study of the effects of stimulant medications on estimates of psycholinguistic abilities for children with attention-deficit/hyperactivity disorder

Underlying deficits in inattention, hyperactivity, and/or impulsivity might contribute to suboptimal test-taking behaviours during language assessments that can lead to diagnostic errors. Considerations of potential medication effects on estimates of children's nonword repetition, sentence recall, tense-marking, and narrative abilities are warranted given long-standing enthusiasm for these indices to serve as clinical markers for developmental language disorder (DLD). A battery consisting of 1 nonverbal, 1 reading, and 6 verbal measures was administered twice to 26 children (6-9 years) with independently diagnosed combined-type attention-deficit/hyperactivity disorder (ADHD). All participants had been prescribed stimulant medications for the management of their ADHD symptoms and were assessed off- and on-medication, with order counter-balanced across participants. Half of the participants had concomitant DLD. Examiners were unaware of children's clinical status during assessments or when they were testing children who had received medication. Effect sizes were calculated for each measure. Significant score differences indicating a beneficial impact of stimulant medications on children's performances were observed on the recalling sentences subtest of the Clinical Evaluation of Language Fundamentals and the Picture Peabody Vocabulary Test. Adjustments may be needed when speech language pathologists use sentence recall or receptive vocabulary measures to make diagnostic decisions with children who have ADHD.

Adult Attention-Deficit/Hyperactivity Disorder: a Narrative Review of Biological Mechanisms, Treatments, and Outcomes

PURPOSE OF REVIEW

Attention-deficit/hyperactivity disorder (ADHD) is a heterogeneous and complex neurodevelopmental disorder related to disruptions in various neuronal structures and pathways, dopamine (DA) transporter, and receptor genes, resulting in cognitive and regulation deficits. This article reviews recent research on the biological mechanisms and markers, clinical manifestations, treatments, and outcomes of adult ADHD as well as current controversies within the field.

RECENT FINDINGS

New research identifies white matter disruptions in multiple cortical pathways in adults with ADHD. New treatments for ADHD in adults such as viloxazine ER have shown preliminary effectiveness in addition to research showing transcranial direct current stimulation can be an effective treatment for adults with ADHD. Although questions exist about the effectiveness of current assessments of and treatments for adult ADHD, recent findings represent a step towards improving the quality of life and outcomes for individuals experiencing this life-long, chronic health condition.

Methylphenidate Enhances Spontaneous Fluctuations in Reward and Cognitive Control Networks in Children With Attention-Deficit/Hyperactivity Disorder

BACKGROUND

Methylphenidate, a first-line treatment for attention-deficit/hyperactivity disorder (ADHD), is thought to influence dopaminergic neurotransmission in the nucleus accumbens (NAc) and its associated brain circuitry, but this hypothesis has yet to be systematically tested.

METHODS

We conducted a randomized, placebo-controlled, double-blind crossover trial including 27 children with ADHD. Children with ADHD were scanned twice with resting-state functional magnetic resonance imaging under methylphenidate and placebo conditions, along with assessment of sustained attention. We examined spontaneous neural activity in the NAc and the salience, frontoparietal, and default mode networks and their links to behavioral changes. Replicability of methylphenidate effects on spontaneous neural activity was examined in a second independent cohort.

RESULTS

Methylphenidate increased spontaneous neural activity in the NAc and the salience and default mode networks. Methylphenidate-induced changes in spontaneous activity patterns in the default mode network were associated with improvements in intraindividual response variability during a sustained attention task. Critically, despite differences in clinical trial protocols and data acquisition parameters, the NAc and the salience and default mode networks showed replicable patterns of methylphenidate-induced changes in spontaneous activity across two independent cohorts.

CONCLUSIONS

We provide reproducible evidence demonstrating that methylphenidate enhances spontaneous neural activity in NAc and cognitive control networks in children with ADHD, resulting in more stable sustained attention. Our findings identified a novel neural mechanism underlying methylphenidate treatment in ADHD to inform the development of clinically useful biomarkers for evaluating treatment outcomes.

The Effect of Meditation-Based Mind-Body Interventions on Symptoms and Executive Function in People With ADHD: A Meta-Analysis of Randomized Controlled Trials

OBJECTIVE

This study aims to perform a systematic review and meta-analysis of the effect of MBIs (Mindfulness, Tai Chi, Yoga, and Qigong) on symptoms and executive function (EF) in ADHD.

METHOD

PubMed, Web of Science, the Cochrane Library, PsycINFO, CINAHL, Embase, and CNKI databases were searched to collect randomized controlled trials (RCTs) on the effects of MBIs on symptoms and EF in ADHD. Data extraction and methodological quality evaluation were conducted by two researchers, and a meta-analysis was conducted by Stata SE.

RESULTS

The pooled meta-analyses of MBIs revealed a positive and small effect on inattention (g = -0.26), hyperactivity/impulsivity (g = -0.19), and EF (g = -0.35).

CONCLUSION

Results suggest that MBIs have a significant improvement relative to the control condition. Although some results show that symptoms are affected by age, interventions, and total time of moderators, while EF is not affected by age and measurement, it needs to be supported by more research evidence. (J. of Att. Dis. XXXX; XX(X) XX-XX).

An overview on neurobiology and therapeutics of attention-deficit/hyperactivity disorder

Attention-Deficit/Hyperactivity Disorder (ADHD) is a prevalent psychiatric condition characterized by developmentally inappropriate symptoms of inattention and/or hyperactivity/impulsivity, which leads to impairments in the social, academic, and professional contexts. ADHD diagnosis relies solely on clinical assessment based on symptom evaluation and is sometimes challenging due to the substantial heterogeneity of the disorder in terms of clinical and pathophysiological aspects. Despite the difficulties imposed by the high complexity of ADHD etiology, the growing body of research and technological advances provide good perspectives for understanding the neurobiology of the disorder. Such knowledge is essential to refining diagnosis and identifying new therapeutic options to optimize treatment outcomes and associated impairments, leading to improvements in all domains of patient care. This review is intended to be an updated outline that addresses the etiological and neurobiological aspects of ADHD and its treatment, considering the impact of the "omics" era on disentangling the multifactorial architecture of ADHD.

Chronic Exercise for Core Symptoms and Executive Functions in ADHD: A Meta-analysis

BACKGROUND AND OBJECTIVES

The effects of chronic exercise interventions (CEIs) on core symptoms and executive functions (EFs) of attention-deficit/hyperactivity disorder (ADHD) and how different characteristics of CEIs could modify the effect remain unclear. We synthesized the current evidence on the effects of CEIs on core symptoms and EFs in children and adolescents with ADHD.

METHODS

Data sources include PubMed, Embase, Web of Science, Cochrane Library, and China National Knowledge Infrastructure from database inception to July 31, 2022. Study selection includes randomized controlled trials that reported on the effects of CEIs on core symptoms and/or EFs in ADHD aged 6 to 18 years.

RESULTS

Twenty-two randomized controlled trials were included. CEIs had a small beneficial effect on overall core symptoms (standardized mean difference [SMD] = -0.39, 95% confidence interval [CI]: -0.64 to -0.14), as well as inattention (SMD = -0.32, 95% CI: -0.63 to -0.004) among children and adolescents with ADHD. Closed-skill exercise showed a large improvement in core symptoms (SMD = -0.83, 95% CI: -1.30 to -0.35), whereas open-skill exercise did not. Additionally, CEIs had a moderately beneficial effect on overall EFs (SMD = -0.68, 95% CI: -0.91 to -0.45) and a moderate-to-large effect on the specific domains of EFs. The pooled effects on overall core symptoms and EFs were not significantly modified by study population (children or adolescents), exercise session duration (≤50 or >50 minutes per session, median), or total exercise sessions (<24 or ≥24 sessions, median).

CONCLUSIONS

CEIs have small-to-moderate beneficial effects on overall core symptoms and EFs in children and adolescents with ADHD.

Parent Training for ADHD: No Generalization of Effects From Clinical to Neuropsychological Outcomes in a Randomized Controlled Trial

OBJECTIVE

We examined whether neuropsychological function in ADHD can be improved by the New Forest Parenting Programme (NFPP), that combines standard parenting strategies with self-regulatory skills training, or predict ADHD and quality of life (QoL) treatment effects.

METHOD

Participants were 93 medication-naive preschool children with ADHD (3-7 years) randomized to either NFPP (n = 49) or treatment as usual (TAU; n = 44) in a recent randomized trial. Laboratory measures of executive function, reaction time variability, and delay of gratification were collected along with parent ratings of ADHD and QoL at baseline and post treatment. Ratings were collected again at 3-month follow-up.

RESULTS

NFPP did not improve neuropsychological function (compared to TAU), and baseline neuropsychological function did not predict treatment-related ADHD or QoL effects.

CONCLUSION

Although NFPP includes a neuropsychological training element and has been shown to improve several clinical outcomes, it did not improve the neuropsychological functions it targets.

Networks of Neuropsychological Functions in the Clinical Evaluation of Adult ADHD

This study applied network analysis to explore the relations between neuropsychological functions of individuals in the clinical evaluation of attention-deficit/hyperactivity disorder (ADHD) in adulthood. A total of 319 participants from an outpatient referral context, that is, 173 individuals with ADHD (ADHD group) and 146 individuals without ADHD (n-ADHD group), took part in this study and completed a comprehensive neuropsychological assessment. A denser network with stronger global connectivity was observed in the ADHD group compared to the n-ADHD group. The strongest connections were consistent in both networks, that is, the connections between selective attention and vigilance, and connections between processing speed, fluency, and flexibility. Further centrality estimation revealed attention-related variables to have the highest expected influence in both networks. The observed relationships between neuropsychological functions, and the high centrality of attention, may help identify neuropsychological profiles that are specific to ADHD and optimize neuropsychological assessment and treatment planning of individuals with cognitive impairment.

The influence of methylphenidate on sustained attention in paediatric acquired brain injury: a meta-analytical review

Impairment in sustained attention is a common consequence of childhood Acquired Brain Injury (ABI). Whilst methylphenidate provides promise in enhancing "attention" as a unitary construct, little work has explored its effectiveness upon individual attentional domains. The current systematic review and meta-analysis evaluates the utility of methylphenidate on sustained attentional performance across childhood ABI groups. Five databases (PsycINFO, MEDLINE, Embase, Scopus & Cochrane Library) were searched for relevant articles from their inception to March 2022. A purpose-developed evaluation tool was used to assess each study's research quality (QuEST:MAP). Nine of the 1600 identified articles were included within this review (n = 259). Meta-analytical findings reported an overall significant benefit of methylphenidate on sustained attention in childhood ABI (g = -0.33, 95% CI: -0.62 to -0.04). Associated summary effect sizes were relatively small, particularly when adjusting for outlier cases. Subgroup analyses identified a significantly greater benefit of methylphenidate in clinical subgroups with comorbid ADHD diagnoses (p < .01). The current evidence base is characterized by small-scale clinical trials with variable research quality and low generalizability. Further robust research is needed to quantify methylphenidate utility upon individual attentional domains in larger and more representative ABI samples.

Methylphenidate significantly improves neurocognitive impairments in children with ADHD

This study aimed to investigate the effects of methylphenidate (MPH) on scores on a neurocognitive test battery for individuals with various presentations of attention deficit/hyperactivity disorder (ADHD) and the effect of comorbidities on executive function. This study included 861 children and adolescents aged 7-17 years who were diagnosed with ADHD according to DSM-V criteria. The CNS Vital Signs Battery was utilized to compare the neuropsychological characteristics and MPH treatment responses of patients with predominantly inattentive (ADHD-I) and combined (ADHD-C) presentations of ADHD. Before MPH administration, a statistically significant difference was observed between groups only for complex attention. In addition, the overall prevalence rate of psychiatric comorbidities was 45.5%, and no statistically significant differences were found in the ADHD-I group pre- versus post-MPH administration. Prior to the administration of MPH, statistically significant differences were observed within the ADHD-C group between those with or without comorbidities. However, after MPH administration, these differences between the groups disappeared. The effects of MPH on improving scores on neuropsychological subtests were similar between the groups with different presentations of ADHD. Additionally, MPH treatment was effective despite the presence of comorbidities.

Methylphenidate remediates aberrant brain network dynamics in children with attention-deficit/hyperactivity disorder: a randomized controlled trial

Methylphenidate is a widely used first-line treatment for attention deficit/hyperactivity disorder (ADHD), but the underlying circuit mechanisms are poorly understood. Here we investigate whether a single dose of osmotic release oral system methylphenidate can remediate attention deficits and aberrancies in functional circuit dynamics in cognitive control networks, which have been implicated in ADHD. In a randomized placebo-controlled double-blind crossover design, 27 children with ADHD were scanned twice with resting-state functional MRI and sustained attention was examined using a continuous performance task under methylphenidate and placebo conditions; 49 matched typically-developing (TD) children were scanned once for comparison. Dynamic time-varying cross-network interactions between the salience (SN), frontoparietal (FPN), and default mode (DMN) networks were examined in children with ADHD under both administration conditions and compared with TD children. Methylphenidate improved sustained attention on a continuous performance task in children with ADHD, when compared to the placebo condition. Children with ADHD under placebo showed aberrancies in dynamic time-varying cross-network interactions between the SN, FPN and DMN, which were remediated by methylphenidate. Multivariate classification analysis confirmed that methylphenidate remediates aberrant dynamic brain network interactions. Furthermore, dynamic time-varying network interactions under placebo conditions predicted individual differences in methylphenidate-induced improvements in sustained attention in children with ADHD. These findings suggest that a single dose of methylphenidate can remediate deficits in sustained attention and aberrant brain circuit dynamics in cognitive control circuits in children with ADHD. Findings identify a novel brain circuit mechanism underlying a first-line pharmacological treatment for ADHD, and may inform clinically useful biomarkers for evaluating treatment outcomes.

The Effects of Neurofeedback on Executive Functioning in Children With ADHD: A Meta-Analysis

OBJECTIVE

Possible beneficial effects of neurofeedback in improving ADHD functional outcomes have been increasingly reported. This meta-analysis aimed to evaluate the relationship between neurofeedback and executive functioning in children with ADHD.

METHODS

PubMed, EMBASE, EBSCO, Web of Science, and Cochrane databases were searched to identify studies reporting the effects of neurofeedback on executive functioning, including response inhibition, sustained attention, and working memory, assessed by neuropsychological tests. Only randomized controlled studies of children aged 5 to 18 years were included using a random-effects model.

RESULTS

Ten studies were included. The effects of neurofeedback were not found on three domains of executive functions. A meta-regression analysis revealed a trend of numbers of neurofeedback sessions positively associated with response inhibition (p = .06).

CONCLUSION

Results did not show the benefits of neurofeedback on executive functions assessed by neuropsychological tests. Future studies should focus on standard neurofeedback protocols, the intensity of intervention, and neuropsychological outcomes.

Pharmacological and non-pharmacological interventions for adults with ADHD: protocol for a systematic review and network meta-analysis

INTRODUCTION

It is unclear how pharmacological and non-pharmacological interventions compare with each other in terms of efficacy and tolerability for core symptoms and additional problems in adults with attention-deficit/hyperactivity disorder (ADHD). We aim to conduct the first network meta-analysis (NMA) comparing pharmacological and non-pharmacological interventions (or their combinations) in adults with ADHD.

METHODS AND ANALYSIS

We will follow the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement for NMAs. We will search a broad set of electronic databases/registries and contact drug companies and experts in the field to retrieve published and unpublished randomised controlled trials (RCTs) (parallel or cross-over) of medications (either licensed or unlicensed) and any non-pharmacological intervention in adults (≥18 years) with ADHD. Primary outcomes will be: (1) change in severity of ADHD core symptoms, and (2) acceptability (all-cause discontinuation). Secondary outcomes will include tolerability (drop-out due to side effects) and change in the severity of emotional dysregulation, executive dysfunctions and quality of life. The risk of bias in each individual RCT included in the NMA will be assessed using the Cochrane Risk of Bias tool-version 2. We will evaluate the transitivity assumption comparing the distribution of possible effect modifiers across treatment comparisons. We will perform Bayesian NMA for each outcome with random-effects model in OpenBUGS. Pooled estimates of NMA will be obtained using the Markov Chains Monte Carlo method. We will judge the credibility in the evidence derived from the NMA using the CINeMA tool (which includes assessment of publication bias). We will conduct a series of sensitivity analyses to assess the robustness of the findings.

ETHICS AND DISSEMINATION

As this is the protocol for an aggregate-data level NMA, ethical approval will not be required. Results will be disseminated at national/international conferences and in peer-reviewed journals.

PROSPERO REGISTRATION NUMBER

CRD42021265576.

Functional interventions as augmentation strategies for obsessive-compulsive disorder (OCD): scoping review and expert survey from the international college of obsessive-compulsive spectrum disorders (ICOCS)

BACKGROUND

Patients with obsessive-compulsive disorder (OCD) commonly exhibit a range of functional difficulties, presumed linked to neurocognitive changes. Evidence-based first-line treatments have limited effect on improving these cognitive-functional problems. Candidate interventions could be used to augment evidence-based treatments by the multi-professional mental health team.

METHODS

A scoping review was performed to identify any intervention with at least one peer-reviewed report of clinical improvement in any of the 13 functional domains of the Cognitive Assessment Instrument of Obsessions and Compulsions (CAIOC-13). Next, an online survey of experts of the International College of Obsessive-Compulsive Spectrum Disorders was conducted.

RESULTS

Forty-four studies were identified reporting a positive outcome for 27 different kinds of intervention. Twenty-six experts from 12 different countries, including at least one expert from each continent, completed the opinion survey. Five interventions were identified as 'highly promising', none of which was moderated by rater-related factors, suggesting global applicability.

CONCLUSION

Patients with OCD may benefit from a detailed functional assessment, to identify areas of unmet need. A variety of interventions show theoretical promise for treating the complex functional difficulties in OCD as adjuncts to first-line treatments, but the published evidence is weak. Randomised controlled trials are needed to determine the clinical effectiveness of these interventions.HighlightsFunctional-cognitive problems are common in patients with OCD.First-line evidence-based treatments have limited effect on these functionalcognitive difficulties.In our scoping review we found 44 studies reporting of improved clinical outcomes in any of the 13 functional domains of the Cognitive Assessment Instrument of Obsessions and Compulsions (CAIOC-13).An online survey of experts of the International College of Obsessive-Compulsive Spectrum Disorders (ICOCS) was conducted and identified five interventions as "highly promising" candidate treatments for functional-cognitive problems in OCD.Randomised controlled trials are needed to determine the clinical effectiveness of these interventions.

A randomised controlled trial (MindChamp) of a mindfulness-based intervention for children with ADHD and their parents

BACKGROUND

Family mindfulness-based intervention (MBI) for child attention-deficit/hyperactivity disorder (ADHD) targets child self-control, parenting and parental mental health, but its effectiveness is still unclear.

METHODS

MindChamp is a pre-registered randomised controlled trial comparing an 8-week family MBI (called 'MYmind') in addition to care-as-usual (CAU) (n = 55) with CAU-only (n = 48). Children aged 8-16 years with remaining ADHD symptoms after CAU were enrolled together with a parent. Primary outcome was post-treatment parent-rated child self-control deficits (BRIEF); post hoc, Reliable Change Indexes were explored. Secondary child outcomes included ADHD symptoms (parent/teacher-rated Conners' and SWAN; teacher-rated BRIEF), other psychological symptoms (parent/teacher-rated), well-being (parent-rated) and mindfulness (self-rated). Secondary parent outcomes included self-ratings of ADHD symptoms, other psychological symptoms, well-being, self-compassion and mindful parenting. Assessments were conducted at post-treatment, 2- and 6-month follow-up.

RESULTS

Relative to CAU-only, MBI+CAU resulted in a small, statistically non-significant post-treatment improvement on the BRIEF (intention-to-treat: d = 0.27, p = .18; per protocol: d = 0.33, p = .11). Significantly more children showed reliable post-treatment improvement following MBI+CAU versus CAU-only (32% versus 11%, p < .05, Number-Needed-to-Treat = 4.7). ADHD symptoms significantly reduced post-treatment according to parent (Conners' and SWAN) and teacher ratings (BRIEF) per protocol. Only parent-rated hyperactivity impulsivity (SWAN) remained significantly reduced at 6-month follow-up. Post-treatment group differences on other secondary child outcomes were consistently favour of MBI+CAU, but mostly non-significant; no significant differences were found at follow-ups. Regarding parent outcomes, significant post-treatment improvements were found for their own ADHD symptoms, well-being and mindful parenting. At follow-ups, some significant effects remained (ADHD symptoms, mindful parenting), some additional significant effects appeared (other psychological symptoms, self-compassion) and others disappeared/remained non-significant.

CONCLUSIONS

Family MBI+CAU did not outperform CAU-only in reducing child self-control deficits on a group level but more children reliably improved. Effects on parents were larger and more durable. When CAU for ADHD is insufficient, family MBI could be a valuable addition.

Biological Bases of Empathy and Social Cognition in Patients with Attention-Deficit/Hyperactivity Disorder: A Focus on Treatment with Psychostimulants

In recent years, there has been growing interest in investigating the effect of specific pharmacological treatments for ADHD not only on its core symptoms, but also on social skills in youths. This stands especially true for ADHD patients displaying impulsive aggressiveness and antisocial behaviors, being the comorbidity with Disruptive Behavior Disorders, one of the most frequently observed in clinical settings. This systematic review aimed to synthesize research findings on this topic following PRISMA guidelines and to identify gaps in current knowledge, future directions, and treatment implications. Search strategies included the following terms: ADHD; methylphenidate and other ADHD drugs; empathy, theory of mind and emotion recognition. Full-text articles were retrieved and data from individual studies were collected. Thirteen studies were finally included in our systematic review. Ten studies assessing changes in empathy and/or theory of mind in patients with ADHD treated after pharmacological interventions were identified. Similarly, seven partially overlapping studies assessing changes in emotion recognition were retrieved. Despite a great heterogeneity in the methodological characteristics of the included studies, most of them reported an improvement in emphatic and theory of mind abilities in youths with ADHD treated with psychostimulants and nonstimulant drugs, as well as positive but less consistent results about emotion recognition performances.

The World Federation of ADHD International Consensus Statement: 208 Evidence-based conclusions about the disorder

BACKGROUND

Misconceptions about ADHD stigmatize affected people, reduce credibility of providers, and prevent/delay treatment. To challenge misconceptions, we curated findings with strong evidence base.

METHODS

We reviewed studies with more than 2000 participants or meta-analyses from five or more studies or 2000 or more participants. We excluded meta-analyses that did not assess publication bias, except for meta-analyses of prevalence. For network meta-analyses we required comparison adjusted funnel plots. We excluded treatment studies with waiting-list or treatment as usual controls. From this literature, we extracted evidence-based assertions about the disorder.

RESULTS

We generated 208 empirically supported statements about ADHD. The status of the included statements as empirically supported is approved by 80 authors from 27 countries and 6 continents. The contents of the manuscript are endorsed by 366 people who have read this document and agree with its contents.

CONCLUSIONS

Many findings in ADHD are supported by meta-analysis. These allow for firm statements about the nature, course, outcome causes, and treatments for disorders that are useful for reducing misconceptions and stigma.

Treatment with Methylphenidate Improves Affective but Not Cognitive Empathy in Youths with Attention-Deficit/Hyperactivity Disorder

Background: Beside the core symptoms, patients with attention-deficit/hyperactivity disorder (ADHD) frequently show relevant difficulty in developing relationships with peers. Although ADHD symptoms may account for social impairment, deficits in cognitive and/or affective empathy have also been involved. Our aim was to investigate the effect of methylphenidate (MPH) treatment on affective and cognitive empathy. Methods: Sixty-one drug-naïve youths with ADHD (age range 6 to 17 years, mean 10.3 ± 2.8 years, 51 males) naturalistically treated with MPH monotherapy were followed up for 6 months for ADHD symptoms and empathy, measured with the Basic Empathy Scale. Results: After being treated with MPH, the patients showed a significant improvement in affective and cognitive empathy scores. Linear regression models showed that changes in inattention symptoms predicted changes in affective but not in cognitive empathy, while changes in the hyperactivity/impulsivity symptoms did not predict changes in affective or cognitive empathy. Conclusions: Our study provides a further contribution for a better understanding of the possible effects of the MPH on youth’s characteristics.

Developing and feasibility testing of the Indonesian computer-based game prototype for children with attention deficit/hyperactivity disorder

The aim of this study was to develop an Indonesian computer-based game prototype, including feasibility testing, targeted on attention deficit/hypersensitivity disorder (ADHD) clinical symptoms and executive function. The study comprised five steps. The first to third steps used an exploratory qualitative research design. The Delphi technique with FGD was applied to collect qualitative data. During the study, seven experts participated in ten FGDs. Feasibility testing was conducted as a one group pre- and post-test design that included ten children with drug-naïve ADHD without other mental or physical disorders. Feasibility data were collected before and after 20 training sessions with the Indonesian computer-based game prototype. The framework analysis was performed for qualitative data. Quantitative data were analyzed using the paired t-test, Pearson's correlation and Spearman's rank-order correlation. Outputs of the exploratory qualitative study were the Indonesian computer-based game prototype constructs and general agreements of the prototype,. The Indonesian computer-based game prototype construct comprised six components: reward-related processing, control inhibition, improved sustained attention, specific timing, increased arousal, and improved emotional regulation. After 20 sessions of training, several indicators decreased significantly, such as CATPRS-teacher rating (18.5 [5.31] vs. 12.9 [5.51], p = 0.047), BRIEF-GEC (64.80 [10.21] vs. 57.50 [7.51], p = 0.02), BRIEF-MI (66.1 [7.61] vs. 58.4 [7.56], p = 0.014), BRIEF-Initiate (66.6 [10.15] vs. 54.1 [6.49], p = 0.008), BRIEF-Working Memory (68.0 [6.89] vs. 60.9 [10.05], p = 0.02), and BRIEF-Organization of Material (60.7 [12.88] vs. 49.3 [11.79], p = 0.04). There was a low to moderate correlation between CATPRS-teacher and -parent rating and several BRIEF domains. Feasibility testing output also included the training procedure guideline. The present study indicated that the Indonesian computer-based game prototype could be used as a framework to develop a fixed computer-based game intervention for children with ADHD. However, further randomized controlled studies need to be conducted to show its effectiveness.

Do effects of methylphenidate on cognitive performance last beyond treatment? A randomized placebo-controlled trial in boys and men with ADHD

Methylphenidate (MPH) is the first-choice pharmacological treatment for treatment of Attention-Deficit/Hyperactivity Disorder (ADHD) across the lifespan. However, it is unclear whether MPH affects cognitive development, while recent (pre-) clinical studies suggest effects on the developing brain. The present randomized, placebo-controlled trial aims to determine whether MPH has short-term, age-dependent effects on cognitive performance in ADHD after a 1-week washout. Effects of 16 weeks MPH treatment were assessed after a one-week washout on cognitive functioning. Boys (age=10-12) and men (age=23-40) with ADHD were assigned to MPH treatment (boys n=25, men n=24) or placebo (boys n=25, men n=24). Outcome measures were working memory, response inhibition, response speed, episodic memory, and delay aversion. Differences in task performances over time (pre-, mid-, and post-treatment, following a 1-week wash-out) were compared between age and treatment conditions with mixed ANOVAs. MPH improved working memory and response speed, but only during treatment. No lasting age*treatment effects were observed post intervention. Overall, the results from the present randomized, placebo-controlled trial show that the effects of MPH on cognition do not extend past treatment in children or adults. While treatment with MPH improves cognition during treatment, these effects appear transient after 16-weeks of treatment. (Title trial: "Effects of methylphenidate on the developing brain"; http://www.trialregister.nl/trialreg/admin/rctview.asp?TC=3103).

Effectiveness of Online Mindfulness-Based Intervention (iMBI) on Inattention, Hyperactivity-Impulsivity, and Executive Functioning in College Emerging Adults with Attention-Deficit/Hyperactivity Disorder: A Study Protocol

Attention-deficit/hyperactivity disorder (ADHD), a common neurodevelopmental disorder, often persists into adulthood. In Malaysia, the prevalence rate of hyperactivity symptoms is highest among Chinese Malaysians. There are limited evidence-based treatment options targeting the core symptoms of ADHD, as well as executive functioning. In addition, conventional psychotherapeutic approaches for adults with ADHD have been found to be highly labor-intensive. The present study will evaluate the effectiveness of an online mindfulness-based intervention to reduce inattention and hyperactivity–impulsivity and improve executive functioning among Chinese Malaysian college emerging adults with ADHD. Informed by established literature, we will design an 8-week online mindfulness-based intervention (i.e., iMBI). We will conduct a two-arm randomized controlled trial comparing an iMBI plus treatment-as-usual group (n = 54) and an enhanced treatment-as-usual control group (n = 54). Outcome measures of inattention, hyperactivity–impulsivity, and executive functioning will be collected at baseline, immediately post-intervention, and 1-month post-intervention. The findings of the present study will not only demonstrate the implementation of iMBI as a new treatment modality but also inform practitioners on the effectiveness of iMBI in reducing the burden of adults living with ADHD.

The Impact of Methylphenidate on QbTest Performance of Children with ADHD: A Retrospective Clinical Study

INTRODUCTION

The Quantified behavior Test (QbTest), which combines a continuous performance task (CPT) and motion tracking, provides data for the core signs of attention-deficit/hyperactivity disorder (ADHD): attention, hyperactivity, and impulsivity. This study aimed to evaluate the performance of children and adolescents with ADHD on the QbTest before and after a single methylphenidate (MPH) dose.

SUBJECTS AND METHODS

This retrospective chart review study included data from 149 children and 215 adolescents who completed the QbTest. A summary index of the CPT and motion capture data on the QbTest is provided by three cardinal parameters: QbActivity, QbImpulsivity, and QbInattention. The test was performed twice on the same day, before and up to three hours after MPH intake. A decrease by ≥ 0.5 in a cardinal parameter score was considered an improvement, whereas an increase by ≥ 0.5 a deterioration.

RESULTS

QbActivity improvement after MPH intake was present in 71.7% and 76.2% of the children and adolescents, respectively. QbImpulsivity improvement was observed in 50.4% of the children and 44.7% of the adolescents, and QbInattention improvement in 85.1% and 91.1% of the children and adolescents, respectively. All three parameters improved simultaneously in 27.7% of the children and 28.7% of the adolescents. The likelihood that one parameter deteriorated after MPH use was greater if that parameter was within the normal range before medication. This was most pronounced for QbImpulsivity. Among male adolescents, QbInattention improvement was often accompanied by QbImpulsivity deterioration.

CONCLUSION

The QbTest inattention and motor activity parameters improved markedly after a single MPH dose in children and adolescents with ADHD, while less so for impulsivity. Improvement of one parameter is not necessarily associated with improvement of the other two, and deterioration, especially regarding impulsivity, may occur. If confirmed, these results highlight the need for optimization and individualization of MPH treatment, while monitoring all aspects of the ADHD symptomatology based on the QbTest performance.

Executive Function Outcome of Treatment with Viloxazine Extended-Release Capsules in Children and Adolescents with Attention-Deficit/Hyperactivity Disorder: A Post-Hoc Analysis of Four Randomized Clinical Trials

AIM

The aim of this study was to evaluate the effect of viloxazine extended-release capsules (viloxazine ER; Qelbree™) on executive function deficits (EFDs) in pediatric subjects (6-17 years of age) with attention-deficit/hyperactivity disorder (ADHD).

METHODS

Data from four phase III placebo-controlled trials of 100-600 mg/day viloxazine ER (6-8 weeks of treatment) were used to evaluate the change from baseline (CFB) in the Conners 3rd Edition Parent Short Form-Executive Function (C3PS-EF) content scale T-score. Subjects were defined as EFD responders if they had C3PS-EF T-score > 70 at baseline and < 65 at end of study. ADHD symptoms were assessed with ADHD Rating Scale 5th Edition (ADHD-RS-5). Subjects were defined as ADHD symptom responders if they had a ≥ 50% reduction in CFB ADHD-RS-5 Total score at Week 6. The number needed to treat (NNT) and Cohen's d effect sizes were estimated for EFD and ADHD symptoms.

RESULTS

A total of 1154 subjects were included in the analysis. Statistically significant improvements in EFDs were observed with viloxazine ER versus placebo (p = 0.0002). There were 52.5% of EFD or ADHD symptom responders in the viloxazine ER treatment group and 35.4% in the placebo group (p < 0.0001). The NNT was 5.8. The Cohen's d effect size for EFD and ADHD symptoms was 0.31.

CONCLUSION

Consistent with the efficacy of viloxazine ER demonstrated in pivotal trials, viloxazine ER significantly reduced EFDs in subjects with ADHD. Moreover, a substantial proportion of subjects treated with viloxazine ER had large improvements in EFDs, ADHD symptoms, or both.

CLINICAL TRIAL REGISTRATION NUMBERS

NCT03247530, NCT03247517, NCT03247543, NCT03247556.

The effects of acute aerobic exercise on inhibitory control and resting state heart rate variability in children with ADHD

The current study examined the effects of acute moderate-intensity aerobic exercise (MAE) on inhibitory control and resting-state heart rate variability (HRV) in children with Attention-Deficit/Hyperactivity Disorder (ADHD). Our data show that acute MAE resulted in higher response accuracy of a modified flanker task regardless of task difficulty for 60 min (p = .001). Aerobic exercise further resulted in more effective conflict detection, as measured by greater amplitude (p = .012) and shorter latency (p = .029) of the N2 component of event-related brain potential, for 60 min regardless of task difficulty. In contrast, acute MAE did not modulate sympathovagal balance signified by HRV at either 30 min or 60 min following exercise cessation. Collectively, our findings suggest that the beneficial effects of acute aerobic exercise on inhibitory control are sustained for 60 min in children with ADHD. However, acute aerobic exercise may not modulate sympathovagal balance during the post-exercise recovery. Overall, we highlight the importance of acute aerobic exercise for children with ADHD as a potential means to facilitate brain health.

The Acute Effects of Aerobic Exercise on Cognitive Flexibility and Task-Related Heart Rate Variability in Children With ADHD and Healthy Controls

Objective: To investigate cognitive flexibility and task-related heart rate variability following moderately intense aerobic exercise and after watching a video in both children with ADHD and healthy controls. Method: Using a cross-over design, participants completed cognitive assessments following exercise and a physically inactive control condition. Behavioral performance was assessed using the Alternate Uses task. Heart rate variability was recorded via electrocardiography during the cognitive task. Results: The statistical analysis revealed that in comparison with the control condition, both groups showed higher cognitive flexibility following aerobic exercise. Moreover, decreased low frequency and high frequency power was observed in the exercise condition. Conclusion: The findings suggest that exercise elicits similar benefits for cognitive flexibility in children with ADHD and healthy controls, partly due to an increase in arousal induced by parasympathetic withdrawal.

Paying attention to attention in depression

Attention is the gate through which sensory information enters our conscious experiences. Oftentimes, patients with major depressive disorder (MDD) complain of concentration difficulties that negatively impact their day-to-day function, and these attention problems are not alleviated by current first-line treatments. In spite of attention's influence on many aspects of cognitive and emotional functioning, and the inclusion of concentration difficulties in the diagnostic criteria for MDD, the focus of depression as a disease is typically on mood features, with attentional features considered less of an imperative for investigation. Here, we summarize the breadth and depth of findings from the cognitive neurosciences regarding the neural mechanisms supporting goal-directed attention in order to better understand how these might go awry in depression. First, we characterize behavioral impairments in selective, sustained, and divided attention in depressed individuals. We then discuss interactions between goal-directed attention and other aspects of cognition (cognitive control, perception, and decision-making) and emotional functioning (negative biases, internally-focused attention, and interactions of mood and attention). We then review evidence for neurobiological mechanisms supporting attention, including the organization of large-scale neural networks and electrophysiological synchrony. Finally, we discuss the failure of current first-line treatments to alleviate attention impairments in MDD and review evidence for more targeted pharmacological, brain stimulation, and behavioral interventions. By synthesizing findings across disciplines and delineating avenues for future research, we aim to provide a clearer outline of how attention impairments may arise in the context of MDD and how, mechanistically, they may negatively impact daily functioning across various domains.

Visual attention in adults with attention-deficit/hyperactivity disorder before and after stimulant treatment

BACKGROUND

Attention-deficit/hyperactivity disorder (ADHD) is a neurodevelopmental disorder which frequently persists into adulthood. The primary goal of the current study was to (a) investigate attentional functions of stimulant medication-naïve adults with ADHD, and (b) investigate the effects of 6 weeks of methylphenidate treatment on these functions.

METHODS

The study was a prospective, non-randomized, non-blinded, 6-week follow-up design with 42 stimulant medication-naïve adult patients with ADHD, and 42 age and parental education-matched healthy controls. Assessments included measures of visual attention, based on Bundesen's Theory of Visual Attention (TVA), which yields five precise measures of aspects of visual attention; general psychopathology; ADHD symptoms; dyslexia screening; and estimates of IQ.

RESULTS

At baseline, significant differences were found between patients and controls on three attentional parameters: visual short-term memory capacity, threshold of conscious perception, and to a lesser extent visual processing speed. Secondary analyses revealed no significant correlations between TVA parameter estimates and severity of ADHD symptomatology. At follow-up, significant improvements were found specifically for visual processing speed; this improvement had a large effect size, and remained when controlling for re-test effects, IQ, and dyslexia screen performance. There were no significant correlations between changes in visual processing speed and changes in ADHD symptomatology.

CONCLUSIONS

ADHD in adults may be associated with deficits in three distinct aspects of visual attention. Improvements after 6 weeks of medication are seen specifically in visual processing speed, which could represent an improvement in alertness. Clinical symptoms and visual attentional deficits may represent separate aspects of ADHD in adults.

The Effects of ADHD Treatment and Reading Intervention on the Fluency and Comprehension of Children with ADHD and Word Reading Difficulties: A Randomized Clinical Trial

Many students with reading difficulties and disabilities (RD) also have Attention Deficit/Hyperactivity Disorder (ADHD). This randomized clinical trial compared the effects of ADHD treatment alone (medication, parent training), intensive reading intervention alone, and their combination on the reading fluency and comprehension of students with both disorders. Students with ADHD and RD were randomly assigned to receive (a) Reading Intervention only (n=74), (b) ADHD Treatment only (n=78), or (c) simultaneous Combined ADHD and RD Treatment (n=70). For phonemic decoding fluency, the Reading Intervention group and the Combined Treatment group both had significantly better outcomes than the ADHD Treatment group, but did not differ from one another. For passage comprehension, the ADHD Treatment group had significantly better outcomes than the Reading Intervention group, while the other groups did not differ from one another. ADHD treatment may support passage comprehension in this population, while fluent decoding is best supported through intensive reading intervention.

Systematic review and meta-analysis of the behavioral effects of methylphenidate in the spontaneously hypertensive rat model of attention-deficit/hyperactivity disorder

The spontaneously hypertensive rats (SHR) are the most widely used model for ADHD. While face and construct validity are consolidated, questions remain about the predictive validity of the SHR model. We aim at summarizing the evidence for the predictive validity of SHR by evaluating its ability to respond to methylphenidate (MPH), the most well documented treatment for ADHD. A systematic review was carried out to identify studies evaluating MPH effects on SHR behavior. Studies (n=36) were grouped into locomotion, attention, impulsivity or memory, and a meta-analysis was performed. Meta-regression, sensitivity, heterogeneity, and publication bias analyses were also conducted. MPH increased attentional and mnemonic performances in the SHR model and decreased impulsivity in a dose-dependent manner. However, MPH did not reduce hyperactivity in low and medium doses, while increased locomotor activity in high doses. Thus, since the paradoxical effect of stimulant in reducing hyperactivity was not observed in the SHR model, our study does not fully support the predictive validity of SHR, questioning their validity as an animal model for ADHD.

Delay Aversion and Executive Functioning in Adults With Attention-Deficit/Hyperactivity Disorder: Before and After Stimulant Treatment

BACKGROUND

Attention deficit hyperactivity disorder is a heterogeneous disorder, associated with deficits in motivation (e.g., delay aversion) and cognition. Methylphenidate is recommended as a first line treatment for attention deficit hyperactivity disorder symptoms, but little is known about its nonacute effects on motivational and cognitive deficits, particularly in adults with attention deficit hyperactivity disorder.

METHODS

We utilized a prospective, non-randomized, non-blinded, 6-week follow-up design with 42 initially stimulant medication-naïve adult patients with moderate to severe attention deficit hyperactivity disorder, and 42 age- and parental education-matched healthy controls. Delay aversion and executive functioning were assessed with 2 questionnaires and 5 performance-based tests.

RESULTS

At baseline, patients and controls differed significantly on performance-based measures (moderate to large effect sizes), and self-report of delay aversion and executive functioning (very large effect sizes). Treatment with methylphenidate medication (mean dose 65.54 mg/d, SD=10.39) was not associated with improvements in performance-based measures of delay aversion and executive functioning compared to controls, although improvements in self-report executive functioning and delay aversion were found. Self-reported delay aversion was most consistently associated with ADHD symptomatology at baseline and after medication.

CONCLUSION

Methylphenidate treatment does not have an effect on performance-based measures of delay aversion and executive functioning, but may have significant effects on self-reported delay aversion and executive functioning. The latter finding should be interpreted cautiously, given the subjective nature of these measures and design limitations. Self-reported delay aversion is most consistently associated with attention deficit hyperactivity disorder symptomatology.

Mindfulness for children with ADHD and Mindful Parenting (MindChamp): Protocol of a randomised controlled trial comparing a family Mindfulness-Based Intervention as an add-on to care-as-usual with care-as-usual only

BACKGROUND

Self-control in childhood has been linked to long-term and cascading effects on health, academic, criminality, wealth and parenting outcomes. Hence it is important to target self-control deficits early in life. Self-control deficits are a hallmark of Attention Deficit/Hyperactivity Disorder (ADHD). Even after receiving care-as-usual (CAU) for ADHD, impaired self-control often remains. Pharmacotherapy can be hampered by side-effects, low adherence and short-term effectiveness. Other limitations of CAU are decreased effectiveness when parents have ADHD and little effect on parental well-being. Mindfulness-Based Interventions (MBIs) are an emerging non-pharmacological approach with potential to improve self-control and well-being in both children and parents. However, there is a lack of sufficiently powered randomised controlled trials (RCTs) to establish their effects in families with ADHD. This study protocol describes an RCT to investigate the effectiveness of a family MBI as an add-on to CAU in treatment of youth with ADHD, and is described in accordance with Standard Protocol Items: Recommendations for Interventional Trials (SPIRIT).

METHODS/DESIGN

An RCT will be conducted in N = 100 children (aged 8-16 years) with ADHD and their parents. The experimental condition will consist of a family MBI (MYmind): 8-week group-based MBI for youth combined with parallel group-based Mindful Parenting for their parents, as an add-on to CAU. The control condition will consist of CAU-only. Assessments will take place at baseline, end of treatment (3 months later), 2 and 6 months' follow-up. Primary outcome measure will be an ecologically valid assessment of child self-control with the parent-rated Behaviour Rating Inventory of Executive Function (BRIEF). Secondary child outcome measures will be teacher-rated BRIEF, computerised self-control tasks and questionnaires on psychological symptoms (e.g. ADHD, symptoms of autism), well-being and mindfulness. For parental outcomes, secondary measures will be self-rated BRIEF, computerised self-control tasks and questionnaires on psychological symptoms, well-being and mindful parenting.

DISCUSSION

The proposed RCT will take account of methodological limitations of previous studies on MBIs in child ADHD populations. The current study will provide valuable information on family MBI as a potential effective intervention in targeting self-control deficits for youth with ADHD and their parents.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03220308 . Retrospectively registered 18 July 2017.

Effects of multisensory stimuli on inhibitory control in adolescent ADHD: It is the content of information that matters

Even though deficits in inhibitory control and conflict monitoring are well-known in ADHD, factors that further modulate these functions remain to be elucidated. One factor that may be of considerable importance is how inhibitory control is modulated by multisensory information processing. We examined the influence of concurrent auditory conflicting or redundant information on visually triggered response inhibition processes in adolescent ADHD patients and healthy controls. We combined high-density event-related potential (ERP) recordings with source localization to delineate the functional neuroanatomical basis of the involved neurophysiological processes. In comparison to controls, response inhibition (RI) processes in ADHD were compromised in conflicting conditions, but showed no differences to controls when redundant or no concurrent auditory information was presented. These effects were reflected by modulations at the response selection stage (P3 ERP) in the medial frontal gyrus (BA32), but not at the attentional selection (P1, N1 ERPs) or resource allocation level (P2 ERP). Conflicting information during RI exerts its influences in adolescent ADHD via response selection mechanisms, but not via attentional selection. It is not the mere presence of concurrent information, but the presence of conflicting information during RI that may destabilize goal shielding processes in medial frontal cortical regions, by means of increasing the automaticity of response tendencies. The occurring RI deficits might relate to the increased impulsivity in adolescent ADHD and a corresponding vulnerability to react to an increased automaticity of pre-potent response tendencies. ADHD patients show a bias to a specific content of information which can modulate inhibitory control.

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Response inhibition (RI) performance in ADHD is modulated by multisensory information.

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Only incongruent/conflicting concurrent information modulates RI performance.

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RI deficits occur if this conflicting information braces the automaticity of response tendencies.

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These deficits relate to a predisposition of ADHD to engage in impulsive behavior.

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This may be due to deficient goal-shielding processes located in the MFG.

Executive functions in trauma-exposed youth: a meta-analysis

An earlier meta-analysis and review indicated that trauma exposure may be related to lower levels of executive functioning in youth. Since different developmental trajectories were found for three core executive functions, the present study focused on working memory, inhibition, and cognitive flexibility specifically. We conducted a multi-level meta-analysis on 55 studies and 322 effect sizes published between 2001 and 2017 that were retrieved from MEDLINE, Embase, and PsycINFO. The 8070 participants in selected studies were aged 2-25 years. We investigated whether the association between constructs would be moderated by trauma-specific moderators (onset, duration, and type), and study (age, gender, ethnicity, and socio-economic status) and measurement (quality) characteristics. We found small to medium effect sizes for working memory (d = -0.49), inhibition (d = -0.46), and cognitive flexibility (d = -0.44). Moderator analyses showed that, for working memory, when studies used low-quality measurements the effect size was significantly stronger than when studies used high-quality measurements.Compared to single trauma-exposed youth, violence-exposed/abused and foster care/adopted youth showed more problems in inhibition, and foster care/adopted youth showed more problems in cognitive flexibility. Our findings imply that trauma-exposed youth have lower levels of executive functions. Clinical practice should incorporate problems in executive functioning, especially working memory, inhibition, and cognitive flexibility, in assessment and treatment guidelines.

Adolescent brain cognitive development (ABCD) study: Overview of substance use assessment methods

One of the objectives of the Adolescent Brain Cognitive Development (ABCD) Study (https://abcdstudy.org/) is to establish a national longitudinal cohort of 9 and 10 year olds that will be followed for 10 years in order to prospectively study the risk and protective factors influencing substance use and its consequences, examine the impact of substance use on neurocognitive, health and psychosocial outcomes, and to understand the relationship between substance use and psychopathology. This article provides an overview of the ABCD Study Substance Use Workgroup, provides the goals for the workgroup, rationale for the substance use battery, and includes details on the substance use module methods and measurement tools used during baseline, 6-month and 1-year follow-up assessment time-points. Prospective, longitudinal assessment of these substance use domains over a period of ten years in a nationwide sample of youth presents an unprecedented opportunity to further understand the timing and interactive relationships between substance use and neurocognitive, health, and psychopathology outcomes in youth living in the United States.

An event-related potential investigation of the acute effects of aerobic and coordinative exercise on inhibitory control in children with ADHD

The current body of evidence suggests that an aerobic exercise session has a beneficial effect on inhibitory control, whereas the impact of coordinative exercise on this executive function has not yet been examined in children with ADHD. Therefore, the present study aims to investigate the acute effects of aerobic and coordinative exercise on behavioral performance and the allocation of attentional resources in an inhibitory control task. Using a cross-over design, children with ADHD-combined type and healthy comparisons completed a Flanker task before and after 20min moderately-intense cycling exercise, coordinative exercise and an inactive control condition. During the task, stimulus-locked event-related potentials were recorded with electroencephalography. Both groups showed an increase of P300 amplitude and decrease of reaction time after exercise compared to the control condition. Investigating the effect of exercise modality, aerobic exercise led to greater increases of P300 amplitude and reductions in reaction time than coordinative exercise in children with ADHD. The findings suggest that a single exercise bout improves inhibitory control and the allocation of attentional resources. There were some indications that an aerobic exercise session seems to be more efficient than coordinative exercise in reducing the inhibitory control deficits that persist in children with ADHD.

Discontinuation of pharmacological treatment of children and adolescents with attention deficit hyperactivity disorder: meta-analysis of 63 studies enrolling 11,788 patients

BACKGROUND

The risk-benefit balance of pharmacological treatment for children and adolescents with ADHD and the factors that moderate this relationship are unclear.

METHODS

A systematic review and meta-analysis of randomised, placebo-controlled clinical trials (RPCCTs) investigating the efficacy of pharmacological treatment in children or adolescents with ADHD was carried out. Meta-analysis of treatment discontinuation, clinician-, parent- and teacher-rated efficacy and adverse events was performed. The effect of covariates was studied.

RESULTS

Sixty-three studies were included. Ten drugs were investigated, with atomoxetine and methylphenidate the most frequently studied. RPCCTs had mostly a short duration (7.9 weeks). All-cause treatment discontinuation was lower with pharmacological treatment than placebo (OR = 0.68). Pharmacological treatment was more efficacious than placebo independently of the rater (clinician, standardised mean difference (SMD) 0.74; parent, SMD = 0.63; or teacher, SMD = 0.75). Evidence of publication bias was found for clinician-rated efficacy, especially in industry-sponsored RPCCT. Psychostimulants showed a higher efficacy and were associated with a better outcome on treatment discontinuation than non-stimulant drugs. Efficacy was smaller in RPCCTs for which a psychiatric comorbid disorder was an inclusion criterion, was larger in studies with a commercial sponsorship and showed a negative association with treatment length.

CONCLUSIONS

In the short term, pharmacological treatment provides moderate-high symptom relief, is safe and shows lower treatment discontinuation than placebo, suggesting a suitable risk-benefit balance, particularly with psychostimulants. The efficacy is lower in patients with a comorbid psychiatric disorder and should be assessed periodically, as it appears to reduce over time. Publication bias of clinician-rated efficacy in studies with a commercial sponsor is suggested.

Verbal working memory-related functional connectivity alterations in boys with attention-deficit/hyperactivity disorder and the effects of methylphenidate

OBJECTIVE

Few studies have investigated verbal working memory-related functional connectivity patterns in participants with attention-deficit/hyperactivity disorder (ADHD). Thus, we aimed to compare working memory-related functional connectivity patterns in healthy children and those with ADHD, and study effects of methylphenidate (MPH).

METHOD

Twenty-two boys with ADHD were scanned twice, under either MPH (single dose, 10 mg) or placebo, in a randomised, cross-over, counterbalanced placebo-controlled design. Thirty healthy boys were scanned once. We used fMRI during a numerical n-back task to examine functional connectivity patterns in case-control and MPH-placebo comparisons, using independent component analysis.

RESULTS

There was no significant difference in behavioural performance between children with ADHD, treated with MPH or placebo, and healthy controls. Compared with controls, participants with ADHD under placebo showed increased functional connectivity within fronto-parietal and auditory networks, and decreased functional connectivity within the executive control network. MPH normalized the altered functional connectivity pattern and significantly enhanced functional connectivity within the executive control network, though in non-overlapping areas.

CONCLUSION

Our study contributes to the identification of the neural substrates of working memory. Single dose of MPH normalized the altered brain functional connectivity network, but had no enhancing effect on (non-impaired) behavioural performance.

Linking ADHD to the Neural Circuitry of Attention

Attention deficit hyperactivity disorder (ADHD) is a complex condition with a heterogeneous presentation. Current diagnosis is primarily based on subjective experience and observer reports of behavioral symptoms - an approach that has significant limitations. Many studies show that individuals with ADHD exhibit poorer performance on cognitive tasks than neurotypical controls, and at least seven main functional domains appear to be implicated in ADHD. We discuss the underlying neural mechanisms of cognitive functions associated with ADHD, with emphasis on the neural basis of selective attention, demonstrating the feasibility of basic research approaches for further understanding cognitive behavioral processes as they relate to human psychopathology. The study of circuit-level mechanisms underlying executive functions in nonhuman primates holds promise for advancing our understanding, and ultimately the treatment, of ADHD.

Pharmacological and non-pharmacological treatment of adults with ADHD: a meta-review

Attention-deficit/hyperactivity disorder (ADHD) is characterised by a persistent and impairing pattern of inattention and/or hyperactivity/impulsivity and it is one of the most common neuropsychiatric conditions. Evidence about interventions of adults with ADHD is growing rapidly and clinicians need a reliable summary of all the best available information in order to better inform their daily practice. We searched MEDLINE, PubMed, PsycINFO and Cochrane databases until 31 May 2016 for systematic reviews about pharmacological and non-pharmacological treatments in adults with ADHD and carried out a meta-review to address clinically relevant questions. We identified a total of 40 papers. Psychostimulants-such as methylphenidate, dexamphetamine, mixed amphetamine salts and lisdexamfetamine-and non-psychostimulants-such as atomoxetine-were the most studied agents. Overall, pharmacological treatments were significantly more efficacious than placebo (standardised mean difference (SMD) 0.45, 95% CI 0.37 to 0.52), albeit less well accepted (OR 1.18, 95% CI 1.02 to 1.36) and tolerated (OR 2.29, 95% CI 1.97 to 2.66). The effects of pharmacological treatment for individuals with co-occurring ADHD and substance use disorder are still uncertain. The evidence for the efficacy and effectiveness of non-pharmacological treatments of ADHD in adults, as well as the combination of pharmacological and non-pharmacological strategies, is only preliminary. In conclusion, while available evidence addressed mainly the efficacy and tolerability of psychostimulants and non-psychostimulants for ADHD core symptoms in the short term, we still need further empirical support for the non-pharmacological and multimodal treatments. A comprehensive evidence-informed hierarchy of ADHD drugs based on their efficacy and tolerability is not yet available but it should be the next research priority in the field.

Efficacy and Tolerability of Different Interventions in Children and Adolescents with Attention Deficit Hyperactivity Disorder

BACKGROUND

Our study is an analysis of multiple publications involving assessing the comparable efficacy and tolerability of six interventions, which are lisdexamfetamine dimesylate (LDX), atomoxetine (ATX), methylphenidate (MPH), clonidine hydrochloride (CLON), guanfacine extended release (GXR), and bupropion, for young patients (6-18 years old) suffering from attention deficit hyperactivity disorder (ADHD).

METHODS

A conventional meta-analysis (MA) was performed to give direct comparisons and a network meta-analysis (NMA) was used to show the combination of direct and indirect evidence. Ranking preference for all the interventions under a certain outcome was given by the surface of cumulative ranking curve area (SUCRA).

RESULTS

Overall, 15,025 participants from 73 studies were involved in our analysis. In the pairwise MA, LDX was associated with less withdrawal than ATX for lack of efficacy. MPH showed less effectiveness than LDX according to ADHD Rating Scale score. Based on the analysis of our NMA, significant results of efficacy that LDX is a competitive drug were observed when evaluating LDX in comparison with other drugs except for CLON. ATX and GXR presented higher rates of abdominal pain morbidity versus inactive treatment.

CONCLUSION

The stimulants LDX and MPH are still highly recommended because they are highly effective and are tolerated well by patients. Among the non-stimulants, CLON can be taken into consideration for its appreciable effectiveness and tolerability. ATX and GXR can be seen as moderate choices.