Cross-modal conflict deficit in children with attention-deficit/hyperactivity disorder.

The difference between the audiovisual incongruent condition and the audiovisual congruent condition is known as cross-modal conflict, which is an important behavioral index to measure the conflict control function. Previous studies have found conflict control deficits in children with attention-deficit/hyperactivity disorder (ADHD), but it is not clear whether and how cross-modal conflict occurs in children with ADHD at different processing levels. The current study adopted the cross-modal matching paradigm to recruit 25 children with ADHD (19 boys and 6 girls) and 24 TD children (17 boys and 7 girls), aiming to investigate the cross-modal conflict effect at the perception and response levels of children with ADHD. The results showed that both groups of children showed significant cross-modal conflict, and there was no significant difference between the ADHD and TD groups in the number of error trials and mean response time. However, the cross-modal conflict effect caused by auditory distractors was different between the ADHD and TD groups; the TD group had stronger auditory conflict at the response level, whereas the ADHD group had weaker auditory conflict. This indicates that the ADHD group had a deficit of auditory conflict at the response level.

A Female-Specific Treatment Group for ADHD-Description of the Programme and Qualitative Analysis of First Experiences.

Background: The diagnostics and treatment of attention-deficit/hyperactivity disorder (ADHD) in women remain insufficient. Fluctuations of reproductive hormones during the premenstrual period, postpartum period, and (peri)menopause are neglected, even though they impact ADHD symptoms and associated mood disorders. Therefore, we created a female-specific treatment group for women with ADHD and premenstrual worsening of ADHD and/or mood symptoms. Methods: We describe the group programme and underlying rationale, offering a qualitative analysis of the participants' evaluation. Results: The seven bi-weekly sessions foreground the menstrual cycle and address several ADHD-specific topics in relation to this cyclical pattern. Concurrently, women track their menstrual cycle and (fluctuating) ADHD and mood symptoms with an adjusted premenstrual calendar. In total, 18 women (25-47 years) participated in three consecutive groups. We analysed the evaluation of the last group. Participants experienced the group as a safe and welcoming space. Recognition was valued by all. The topics discussed were deemed valuable, and the structure suited them well. Completing the premenstrual calendar augmented the awareness and recognition of individual cyclical symptoms. A lifespan approach increased self-understanding. Participants took their menstrual cycle more seriously, prioritising self-acceptance and self-care. Conclusions: Exploring a cyclical approach in a group setting seems to be a positive addition to treatment for female ADHD.

Breaking It Down: A Systematic Review Unravelling the Impact of Attention Deficit Hyperactivity Disorder and Methylphenidate on Childhood Fractures.

Limb fractures are a common cause of pediatric hospital admissions and surgeries, with a significant prevalence in the United Kingdom across all injury categories. Among psychiatric conditions in children, attention deficit hyperactivity disorder (ADHD) stands out as frequently associated with fractures, particularly those involving extremities. ADHD, with diagnoses prevalent among a significant proportion of school-age children and adolescents, has witnessed a growing global incidence. We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 checklist for our systematic literature search, using various databases and specific search terms related to ADHD and fractures. We considered articles from 2018 to 2023, focusing on English language papers with free full-text access. Our selection process used the PRISMA flowchart. We began with 1,890 articles and, after deduplication, title screening, abstract assessment, and quality evaluation included nine research papers in our review. Our primary focus was on examining fracture-related outcomes in individuals with ADHD compared to those without, considering medication status. These studies encompassed various designs, with a focus on the ADHD-fracture relationship and methylphenidate's (MPH) impact. Our study confirms that ADHD increases fracture risk and suggests that MPH may help mitigate this risk. Early ADHD detection is vital for nonpharmacological interventions. Orthopedic surgeons should proactively identify ADHD, while healthcare professionals should offer injury prevention guidance, particularly for at-risk groups.

Executive function deficits mediate the relationship between employees' ADHD and job burnout.

Adults with Attention-Deficit/Hyperactivity Disorder (ADHD) often face significant deficits in executive function and adverse work-related outcomes. This study aimed to explore the role of executive function deficits in job burnout of employees with ADHD. We hypothesized that employees with ADHD, relative to employees without ADHD, will experience higher levels of job burnout and deficits in executive function. We also hypothesized that the ADHD-job burnout relationship would be mediated through executive function deficits, specifically by self-management to time and self-organization/problem-solving. A field study with 171 employees provided support for the research hypotheses and mediation model in which the employees' ADHD-job burnout relationship was mediated through executive function deficits. Additional mediation analyses indicated that the specific executive function of self-management to time and self-organization/problem-solving mediated the effect of ADHD on job burnout and its facets. Specifically, for physical fatigue, the mediation was realized through self-management to time, and for emotional exhaustion and cognitive weariness, the mediation was significant through self-organization/problem-solving. The present findings shed light on the relevance of referring ADHD among employees, their vulnerability to job burnout, and the role of executive function deficits in job burnout of employees with ADHD.

Exploring autism spectrum disorder (ASD) and attention deficit disorder (ADD/ADHD) in children exposed to polybrominated biphenyl.

Background: Although the causes of attention-deficit/hyperactivity disorder (ADHD) and autism have not been identified, exposure to endocrine-disrupting chemicals, such as polybrominated biphenyl (PBB), during fetal development and early life has been suspected to impact neurological development. This study aims to investigate the association between prenatal and early life exposure to PBB and the development of ADHD and autism later in life. Methods: Data from the Michigan PBB Registry, a cohort of Michigan residents who had been exposed to PBB in a mass contamination event in 1973, was leveraged for this nested case-control analysis among two distinct samples: (1) Those who self-reported ADHD or autism diagnosis, and (2) mothers who reported their child's ADHD or autism diagnosis. PBB exposure was measured in participants of the PBB Registry, and the mother's PBB level was used in mother-reported analyses. Cases were matched with controls by sex and year of birth. Conditional logistic regression models were used to estimate the association between PBB level and case status. Results: PBB levels were higher among those who were exposed in early life compared with those exposed in utero (geometric mean: 0.300 ng/ml vs. 0.016 ng/ml). Among women in this cohort, a higher than expected proportion of self-reported ADHD diagnosis (11.11%), compared with population estimates. PBB was not associated with ADHD or autism in either self-reported or mother-reported analyses. Conclusions: This study adds to the sparse literature about prenatal and early life exposure to PBB-153 and ADHD and autism. Future studies should examine potential effect modification by sex.

Methylphenidate-Induced Non-ischemic Heart Failure With Reduced Ejection Fraction and Mild Pulmonary Hypertension.

Attention-deficit hyperactivity disorder (ADHD) is a neurodevelopmental disorder that is commonly diagnosed during childhood. Patients present with hyperactive-impulsive behavior and/or inappropriate inattention which may persist through adulthood. Central nervous system stimulants have been used to manage patients with ADHD. Methylphenidate which is used as a first-line therapy has been shown to have adverse cardiovascular effects in these patients. This is a case of a young male with a history of ADHD since childhood on methylphenidate who was diagnosed with acute non-ischemic heart failure with an ejection fraction of 15-20%. Methylphenidate-induced heart failure is the rare adverse effect seen in ADHD patients who are on this medication. Our patient was started on goal-directed medical therapy for heart failure and was discharged with an implantable cardioverter defibrillator (LifeVest®, ZOLL, Pittsburgh, PA) because of his persistently low left ventricular ejection fraction. It is important for physicians to always consider heart failure as a possible cardiovascular adverse effect when starting patients on methylphenidate for the management of ADHD.

Alternative Treatments to Pharmacological Therapy in Pediatric Populations With Attention-Deficit/Hyperactivity Disorder (ADHD): A Scoping Review.

In recent years, there has been an increase in the prevalence of the diagnosis of attention-deficit/hyperactivity disorder (ADHD), a cognitive and behavioral disorder in which individuals present with inattention and impulsivity, in the pediatric population. With an increase in diagnoses, there is also increasing concern regarding overdiagnosis and overtreatment with medications for ADHD. The objective of this study was to map out and compile the recent literature pertaining to alternative therapies (e.g., physical activity, diet, mindfulness, and computer-based interventions) for children and adolescents diagnosed with ADHD in an attempt to reduce or replace the use of pharmacological therapy. This scoping review searched articles from multiple databases (PubMed, ScienceDirect, Web of Science, Directory of Open Access Journals, Scopus, and CINAHL). Using search terms "children with ADHD," "alternative treatment," and "cognitive behavioral therapy," articles were identified that were specific to the research question. The inclusion criteria were patients under the age of 18 with a previous diagnosis of ADHD, no other comorbid illnesses, alternative treatments, and was limited to studies published between 2012 and 2022. After removing duplicates, screening for eligibility criteria, and conducting a critical appraisal of the articles, 16 articles were retained for the final review. The main alternative therapeutic domains that emerged were (1) physical activity, (2) diet, (3) mindfulness, (4) computer-based interventions, and (5) miscellaneous interventions. Seven articles assessed the effect of physical activity on executive and cognitive function in children and adolescents with ADHD. Most findings showed improvement with increased physical activity. Two articles explored the effect of diet on the improvement of ADHD symptoms and reported a positive impact. The two articles that evaluated the effects of mindfulness on ADHD symptoms reported a reduction in ADHD symptoms. Two studies evaluated the use of computer-based interventions as an adjunct treatment in children and adolescents with ADHD; improvements in symptoms were reported. One study each evaluated interventions based on music and nerve stimulation. These showed an improvement in attention, memory, and executive function. With the increasing prevalence of ADHD diagnosis in children and adolescents, alternative and/or adjunctive treatments may be a viable and valuable alternative to pharmaceutical interventions. The findings from this review suggest that multiple non-pharmacological interventions effectively reduce symptoms of ADHD in children and adolescents, including diet, exercise, mindfulness, computer-based interventions, music, and nerve stimulation. While there are implications for alternatives to be used in the future, more research is warranted using larger samples with controlled trials.

The impact of transcranial direct current stimulation on attention bias modification in children with ADHD.

Individuals with attention deficit-hyperactivity disorder (ADHD) struggle with the interaction of attention and emotion. The ventromedial prefrontal cortex (vmPFC) and dorsolateral prefrontal cortex (dlPFC) are assumed to be involved in this interaction. In the present study, we aimed to explore the effect of stimulation applied over the dlPFC and vmPFC on attention bias in individuals with ADHD. Twenty-three children with ADHD performed the emotional Stroop and dot probe tasks during transcranial direct current stimulation (tDCS) in 3 conditions: anodal dlPFC (F3)/cathodal vmPFC (Fp2), anodal vmPFC (Fp2)/cathodal dlPFC (F3), and sham stimulation. Findings suggest reduction of attention bias in both real conditions based on emotional Stroop task and not dot probe task. These results were independent of emotional states. The dlPFC and vmPFC are involved in attention bias in ADHD. tDCS can be used for attention bias modification in children with ADHD.

ADHD-AID: Aiding Tool for Detecting Children's Attention Deficit Hyperactivity Disorder via EEG-Based Multi-Resolution Analysis and Feature Selection.

The severe effects of attention deficit hyperactivity disorder (ADHD) among adolescents can be prevented by timely identification and prompt therapeutic intervention. Traditional diagnostic techniques are complicated and time-consuming because they are subjective-based assessments. Machine learning (ML) techniques can automate this process and prevent the limitations of manual evaluation. However, most of the ML-based models extract few features from a single domain. Furthermore, most ML-based studies have not examined the most effective electrode placement on the skull, which affects the identification process, while others have not employed feature selection approaches to reduce the feature space dimension and consequently the complexity of the training models. This study presents an ML-based tool for automatically identifying ADHD entitled "ADHD-AID". The present study uses several multi-resolution analysis techniques including variational mode decomposition, discrete wavelet transform, and empirical wavelet decomposition. ADHD-AID extracts thirty features from the time and time-frequency domains to identify ADHD, including nonlinear features, band-power features, entropy-based features, and statistical features. The present study also looks at the best EEG electrode placement for detecting ADHD. Additionally, it looks into the location combinations that have the most significant impact on identification accuracy. Additionally, it uses a variety of feature selection methods to choose those features that have the greatest influence on the diagnosis of ADHD, reducing the classification's complexity and training time. The results show that ADHD-AID has provided scores for accuracy, sensitivity, specificity, F1-score, and Mathew correlation coefficients of 0.991, 0.989, 0.992, 0.989, and 0.982, respectively, in identifying ADHD with 10-fold cross-validation. Also, the area under the curve has reached 0.9958. ADHD-AID's results are significantly higher than those of all earlier studies for the detection of ADHD in adolescents. These notable and trustworthy findings support the use of such an automated tool as a means of assistance for doctors in the prompt identification of ADHD in youngsters.

Are Sleep Aids Associated with the Severity of Attention Deficit Hyperactivity Disorder Symptoms in Adults Screened for Insomnia? A Cross-Sectional Study.

(1) Background: Attention Deficit Hyperactivity Disorder (ADHD)-like symptoms and insomnia are closely related. The present study examined whether the use of different sleep aids was related to severe ADHD-like symptoms in Jordanian adults screened for insomnia. (2) Methods: This cross-sectional study used predefined inclusion criteria. The severity of ADHD was assessed using the validated Arabic version of the Adult ADHD Self-Report Scale. (3) Results: Data were analyzed from 244 subjects who met the inclusion criteria for severe insomnia, of which 147 (65.3%) reported not using any sleep aid, 50 (22.3%) reported using homeopathy remedies as sleep aids, and 41 (18.3%) reported using over-the-counter antihistamines as sleep aids. Regression analysis revealed that the use of such sleep aids-namely, "homeopathy herbal remedies" and "over-the-counter antihistamines"-was not associated (p > 0.05) with ADHD-like symptoms. However, "age above 31 years old" was significantly associated (B = -3.95, t = -2.32, p = 0.002) with lower ADHD severity, while the "diagnosis with chronic diseases" was significantly associated (B = 4.15, t = 1.99, p = 0.04) with higher ADHD severity. (4) Conclusions: Sleep aids are not associated with ADHD-like symptoms in adults. More research is required to uncover the risk factors for adult ADHD, especially insomnia.

Transcranial random noise stimulation (tRNS) improves hot and cold executive functions in children with attention deficit-hyperactivity disorder (ADHD).

Children with attention deficit-hyperactivity disorder (ADHD) have impaired hot and cold executive functions, which is thought to be related to impaired ventromedial and dorsolateral prefrontal cortex (vmPFC and dlPFC) functions. The present study aimed to assess the impact concurrent stimulation of dlPFC and vmPFC through transcranial random noise stimulation (tRNS), a non-invasive brain stimulation tool which enhances cortical excitability via application of alternating sinusoidal currents with random frequencies and amplitudes over the respective target regions on hot and cold executive functions. Eighteen children with ADHD received real and sham tRNS over the left dlPFC and the right vmPFC in two sessions with one week interval. The participants performed Circle Tracing, Go/No-Go, Wisconsin Card Sorting, and Balloon Analogue Risk Tasks during stimulation in each session. The results showed improved ongoing inhibition, prepotent inhibition, working memory, and decision making, but not set-shifting performance, during real, as compared to sham stimulation. This indicates that simultaneous stimulation of the dlPFC and the vmPFC improves hot and cold executive functions in children with ADHD.

Validation of the Self-Report Version of the German Strengths and Weaknesses of ADHD Symptoms and Normal Behavior Scale (SWAN-DE-SB).

Adults with attention-deficit/hyperactivity disorder (ADHD) experience impairing levels of inattention and/or hyperactivity-impulsivity, while individuals without ADHD experience these symptoms to a lesser extent. Yet, ADHD self-report scales so far hardly captured continuous distributions across the general population. In addition, they focused on weaknesses and ignored strengths. To address these shortcomings, we present here the Strengths and Weaknesses of ADHD and Normal-Behavior Scale Self-Report (SWAN-DE-SB). The normal distribution of the data collected and the scale's internal consistency, and factorial and convergent validity were assessed using data from a general population sample. Its clinical utility was evaluated by comparing scores from a clinical sample and a sample of individuals without ADHD and by calculating optimal cut-off values for specificity and sensitivity. The SWAN-DE-SB demonstrated normal distribution of the data collected, high internal consistency, and factorial and convergent validity. It reliably discriminated individuals with and without ADHD, with high specificity and sensitivity. It should therefore be considered a psychometrically convincing measure to assess strengths and weaknesses of ADHD symptoms and normal behavior in clinical and general population samples.

A state-of-the-art overview of candidate diagnostic biomarkers for Attention-deficit/hyperactivity disorder (ADHD).

INTRODUCTION: Attention-deficit/hyperactivity disorder (ADHD) is one of the most common neurodevelopmental conditions and is highly heterogeneous in terms of symptom profile, associated cognitive deficits, comorbidities, and outcomes. Heterogeneity may also affect the ability to recognize and diagnose this condition. The diagnosis of ADHD is primarily clinical but there are increasing research efforts aiming at identifying biomarkers that can aid the diagnosis. AREAS COVERED: We first discuss the definition of biomarkers and the necessary research steps from discovery to implementation. We then provide a broad overview of research studies on candidate diagnostic biomarkers in ADHD encompassing genetic/epigenetic, biochemical, neuroimaging, neurophysiological and neuropsychological techniques. Finally, we critically appraise current limitations in the field and suggest possible ways forward. EXPERT OPINION: Despite the large number of studies and variety of techniques used, no promising biomarkers have been identified so far. Clinical and biological heterogeneity as well as methodological limitations, including small sample size, lack of standardization, confounding factors, and poor replicability, have hampered progress in the field. Going forward, increased international collaborative efforts are warranted to support larger and more robustly designed studies, develop multimodal datasets to combine biomarkers and improve diagnostic accuracy, and ensure reproducibility and meaningful clinical translation.

Entrepreneurial mental health in the wake of COVID-19 in China with an emphasis on attention deficit hyperactivity disorder (ADHD) and dyslexia analysis.

The COVID-19 pandemic has precipitated a global mental health crisis, with a particularly pronounced impact on the entrepreneurial sector. This paper presents a comparative analysis of mental health challenges among entrepreneurs in China during the pandemic, with a specific focus on attention deficit hyperactivity disorder (ADHD) and Dyslexia. The study assesses the prevalence of ADHD and dyslexia symptoms among established and emerging entrepreneurs in China, finding notable occurrences within this group. The research also examines the self-care practices of these entrepreneurs, shedding light on their approaches during the pandemic period. The findings highlight a complex interplay between mental health issues and entrepreneurial activities, suggesting that certain ADHD and dyslexia traits may offer unexpected benefits in the entrepreneurial realm. These insights are critical for developing supportive frameworks that leverage the strengths of neurodiverse entrepreneurs while mitigating associated challenges, especially in a post-pandemic economic landscape. The study concludes with policy and practice recommendations to bolster the wellbeing and resilience of entrepreneurs facing the multifaceted impacts of the pandemic.

Comparative Pharmacokinetics Research of 13 Bioactive Components of Jieyu Pills in Control and Attention Deficit Hyperactivity Disorder Model Rats Based on UPLC-Orbitrap Fusion MS.

Jieyu Pills (JYPs), a Chinese medicine consisting of 10 herbal elements, have displayed promising clinical effectiveness and low by-effects in the treatment of depression. Prior investigations mostly focused on elucidating the mechanism and therapeutic efficacy of JYPs. In our earlier study, we provided an analysis of the chemical composition, serum pharmacochemistry, and concentrations of the main bioactive chemicals found in JYPs. However, our precise understanding of the pharmacokinetics and metabolism remained vague. This study involved a comprehensive and meticulous examination of the pharmacokinetics of 13 bioactive compounds in JYPs. Using UPLC-Orbitrap Fusion MS, we analyzed the metabolic characteristics and established the pharmacokinetic parameters in both control rats and model rats with attention deficit hyperactivity disorder (ADHD) following oral administration of the drug. Before analysis, plasma samples that were collected at different time intervals after the administration underwent methanol pre-treatment with Puerarin used as the internal standard (IS) solution. Subsequently, the sample was chromatographed on a C18 column employing gradient elution. The mobile phase consisted of methanol solution containing 0.1% formic acid in water. The electrospray ionization source (ESI) was utilized for ionization, whereas the scanning mode employed was selected ion monitoring (SIM). The UPLC-Orbitrap Fusion MS method was subjected to a comprehensive validation process to assess its performance. The method demonstrated excellent linearity (r ≥ 0.9944), precise measurements (RSD < 8.78%), accurate results (RE: -7.88% to 8.98%), and appropriate extraction recoveries (87.83-102.23%). Additionally, the method exhibited minimal matrix effects (87.58-101.08%) and satisfactory stability (RSD: 1.52-12.42%). These results demonstrated adherence to the criteria for evaluating and determining biological material. The 13 bioactive compounds exhibited unique pharmacokinetic patterns in vivo. In control rats, all bioactive compounds except Ferulic acid exhibited linear pharmacokinetics within the dose ranges. In the ADHD model, the absorption rate and amount of most of the components were both observed to have increased. Essentially, this work is an important reference for examining the metabolism of JYPs and providing guidelines for clinical therapy.

Corrigendum: Phytotherapy for attention deficit hyperactivity disorder (ADHD): a systematic review and meta-analysis.

[This corrects the article DOI: 10.3389/fphar.2022.827411.].

The association between pain and psychiatric conditions in adolescents: The impact of gender and ADHD diagnosis

Background and objectives The relationship between pain and psychiatric conditions in children and adolescents has been understudied. This study aimed to investigate the influence of gender on the association between pain and psychiatric diagnoses, as well as the specific relationship between pain and attention deficit/hyperactivity disorder (ADHD), in a sample of adolescents from the general population. Additionally, the study explored whether pain frequency or intensity in individuals with ADHD was influenced by coexisting psychiatric disorders and ADHD medications. Methods This cross-sectional study included 1608 conveniently sampled Swedish upper secondary school students aged 15–19 years. Data were collected at the end of 2020 using the electronic "Mental and Somatic Health without borders" survey. Results A significant positive association (p < 0.001) was observed between pain frequency, intensity, and the presence of any psychiatric diagnosis. Female adolescents reported more frequent and intensive pain in the groups with or without any psychiatric diagnosis and in those with ADHD, however the presence of a psychiatric diagnosis had a comparatively lesser impact on pain frequency in females when compared to males. In adolescents with ADHD, pain frequency, but not intensity, showed a significant further increase. Moreover, the presence of coexisting depression and/or anxiety further heightened the association between pain frequency and ADHD. Notably, common ADHD medications did not have a significant impact on pain experiences. Headache emerged as the most prevalent type of pain across all groups of adolescents. Back pain specifically appeared as the next most common type of pain among adolescents with ADHD. Conclusion The findings suggest a positive association between pain and the presence of psychiatric diagnoses, including ADHD, in adolescents. Gender modified this association. Back pain arised specifically coupled to ADHD. ... (AU)

Assessing the Contribution of Measures of Attention and Executive Function to Diagnosis of ADHD or Autism.

Attention and executive function (EF) dysregulation are common in a number of disorders including autism and attention-deficit/hyperactivity disorder (ADHD). Better understanding of the relationship between indirect and direct measures of attention and EF and common neurodevelopmental diagnoses may contribute to more efficient and effective diagnostic assessment in childhood. We obtained cognitive (NIH Toolbox, Little Man Task, Matrix Reasoning Task, and Rey Delayed Recall) and symptom (CBCL, and BPMT) assessment data from the Adolescent Brain and Cognitive Development (ABCD) database for three groups, autistic (N = 110), ADHD (N = 878), and control without autism or ADHD diagnoses (N = 9130) and used ridge regression to determine which attention and EF assessments were most strongly associated with autism or ADHD. More variance was accounted for in the model for the ADHD group (31%) compared to the autism group (2.7%). Finally, we ran odds ratios (using clinical cutoffs where available and 2 standard deviations below the mean when not) for each assessment measure, which generally demonstrated a greater significance within the indirect measures when compared to the direct measures. These results add to the growing literature of symptom variably across diagnostic groups allowing for better understanding of presentations in autism and ADHD and how best to assess diagnosis. It also highlights the increased difficulty in differentiating autism and controls when compared to ADHD and controls and the importance of indirect measures of attention and EF in this differentiation.

Subcortico-Cortical Dysconnectivity in ADHD: A Voxel-Wise Mega-Analysis Across Multiple Cohorts.

OBJECTIVE: A large body of functional MRI research has examined a potential role for subcortico-cortical loops in the pathogenesis of attention deficit hyperactivity disorder (ADHD), but has produced inconsistent findings. The authors performed a mega-analysis of six neuroimaging data sets to examine associations between ADHD diagnosis and traits and subcortico-cortical connectivity. METHODS: Group differences were examined in the functional connectivity of four subcortical seeds in 1,696 youths with ADHD diagnoses (66.39% males; mean age, 10.83 years [SD=2.17]) and 6,737 unaffected control subjects (47.05% males; mean age, 10.33 years [SD=1.30]). The authors examined associations between functional connectivity and ADHD traits (total N=9,890; 50.3% males; mean age, 10.77 years [SD=1.96]). Sensitivity analyses were used to examine specificity relative to commonly comorbid internalizing and non-ADHD externalizing problems. The authors further examined results within motion-matched subsamples, and after adjusting for estimated intelligence. RESULTS: In the group comparison, youths with ADHD showed greater connectivity between striatal seeds and temporal, fronto-insular, and supplementary motor regions, as well as between the amygdala and dorsal anterior cingulate cortex, compared with control subjects. Similar findings emerged when ADHD traits were considered and when alternative seed definitions were adopted. Dominant associations centered on the connectivity of the caudate bilaterally. Findings were not driven by in-scanner motion and were not shared with commonly comorbid internalizing and externalizing problems. Effect sizes were small (largest peak d, 0.15). CONCLUSIONS: The findings from this large-scale mega-analysis support established links with subcortico-cortical circuits, which were robust to potential confounders. However, effect sizes were small, and it seems likely that resting-state subcortico-cortical connectivity can capture only a fraction of the complex pathophysiology of ADHD.