Large-scale Brain Organization During Cognitive Control in ADHD
Attention Deficit Hyperactivity DisorderThe purpose of this study is to test whether children with attention-deficit/hyperactivity disorder (ADHD) are impaired in the ability to flexibly adapt brain network organization in response to shifting cognitive demands during the exertion of cognitive control, by assessing changes in network dynamics resulting from stimulant administration in children with ADHD, and how those changes relate to behavioral and symptom improvements. Subjects will be children with ADHD aged 8-12. Subjects will participate in multiple testing sessions that include: diagnosis and eligibility screening, neuropsychological and behavioral testing, and, if eligible, MRI scans and a medication challenge. Children with ADHD who are enrolled in the medication challenge will undergo one MRI scan on placebo and one MRI scan on stimulant medication, counterbalanced and double-blind. Functional connectivity will be measured using functional MRI and innovative graph theoretical analytic tools will be implemented. Network metrics will be related to symptomatology and behavioral testing measures. It is hypothesized that stimulant administration in children with ADHD will increase flexibility in network reconfiguration in response to changing cognitive control demands as compared to when they are on placebo. It is further hypothesized that the degree to which brain network organization is changed will be related to the degree of improvement in cognitive control performance.
Stimulant Medication Effects on Auditory Sensitivity in Teens With ADHD
Attention Deficit Hyperactivity DisorderAttention Deficit Disorder1 moreThe aims of this study are to evaluate auditory sensitivity in teenagers with ADHD using acoustic reflex thresholds (ART) and to examine the effects of ADHD stimulant medication on ART.
Adult Outcome of Children With Attention-deficit/Hyperactivity Disorder
Attention Deficit Hyperactivity DisorderAttention deficit/hyperactivity disorder (ADHD) has been recognized as a common (5-8%), early-onset, long-term impairing, heterogeneous neuropsychiatric disorder with high heritability. Due to its lifelong impairments up to adulthood, adult ADHD has drawn much more attention in Western studies in the past decade; however, there has been no such study in Asian countries. The ultimate goals of this longitudinal follow-up study are to investigate the outcomes of a cohort of children with attention-deficit/hyperactivity (ADHD) and their healthy controls at young adulthood as the primary aim; and to test whether structural and functional brain connectivity can be endophenotypes of ADHD, to localize the brain area that are corresponding to methylphenidate treatment effects, and to identify the genetic variants corresponding to the persistence of ADHD, treatment effect of methylphenidate, neurocognitive dysfunction, and structural and functional dysconnectivity in the brain as the secondary aims. With the accomplishment of these goals, this study will provide the first-hand data on adult ADHD in non-western countries, and will be one of few world-class studies on the topics of neurocognitive and imaging genomics on adult ADHD.
Attention-Deficit/Hyperactivity Disorder (ADHD) Brain Activity Changes to Psychostimulants
Attention Deficit Hyperactivity DisorderThe purpose of this study is to examine the neural basis of response inhibition, working memory, and sustained attention in adolescents and adults with Attention-Deficit/Hyperactivity Disorder (ADHD), with particular emphasis on quantifying the effects of methylphenidate (i.e., treatment with psychostimulants) on neural function. Participants will undergo electrophysiological measurement of brain function during laboratory cognitive tasks. This research is aimed to develop a better understanding of how ADHD neural dysfunction relates to clinical presentation and medication response during the transition from adolescence to adulthood. The specific aims and hypotheses are: Specific Aim: To characterize the effect of Ritalin (methylphenidate) on neural activity underlying performance on the response inhibition task in ADHD adolescents and adults. Hypothesis 1) Methylphendiate will increase N2 and P3 amplitude in ADHD persons during medicated EEG sessions; Hypothesis 2) There will be a significant age × medication interaction such that ADHD teens will show increased amplitude of N2 while medicated, particularly at frontal sites, whereas ADHD adults will show differentially greater effect of medication on P3 amplitude and latency at central sites. Hypothesis 3) Brain activity assessed by fMRI will differ between unmedicated and medicated states.
The Effectiveness of Atomoxetine on Brain Imaging, Neuropsychological, and Social Functions in Adults...
Attention Deficit Hyperactivity DisorderAttention deficit/hyperactivity disorder (ADHD) has been recognized as a common (5-8%), early-onset, long-term impairing, heterogeneous neuropsychiatric disorder with high heritability. Pharmacotherapy (methylphenidate and atomoxetine) has been proved to be the most effective treatment for ADHD. Gau (PI) has done extensive research on ADHD and published 7 SCI papers in ADHD pharmacotherapy. The PI published the first paper in the effectiveness of atomoxetine in improving executive functions among 30 boys with ADHD in the world (International Journal of Neuropsychopharmacology, 2009 Oct 23:1-14. [Epub]). Due to its lifelong impairments up to adulthood, adult ADHD has drawn much more attention in Western studies in the past decade; however, there is lack of such information in Asian population except the PI's three SCI papers on adult ADHD. Because little is known about atomoxetine effect in adults with ADHD except symptoms reduction, this proposal aims to investigate the efficacy of atomoxetine beyond symptoms improvement. The significance of this project is its novelty and research and clinical relevance because there is lack of information regarding long-term effect of atomoxetine on neuropsychological and brain imaging functions on adults with ADHD, a high-prevalent mental disorder with long-term impairment in adults.
Lisdexamfetamine Dimesylate (LDX) Pilot Cognition Study to Evaluate the Utility of a Standardized...
Attention-Deficit Hyperactivity DisorderTo evaluate the sensitivity and responsiveness of a standardized, validated, computer-based, battery of neuro-psychometric tests in adults with ADHD.
Evaluating Clinical Outcomes of Treatment Effectiveness for Children and Adults With ADHD
Attention-Deficit/Hyperactivity Disorder (ADHD)To evaluate clinical effectiveness of medication treatment for ADHD. It is hypothesized that the effectiveness is lower than efficacy outcomes measured in clinical trials
An Open Label Phase I/II Study of the Safety and Dopamine Transporter Binding Properties of C-11...
Attention Deficit Hyperactivity DisorderThe primary objective of this study is to evaluate the Binding Potential in subjects with ADHD and adults without ADHD: the intent being to demonstrate that C-11 Altropane PET can be used to differentiate adults with ADHD from healthy control subjects.
Impact of Attention Deficit/Hyperactivity Disorder and Substance Use Disorder on Motorcycle Traffic...
Attention Deficit Hyperactivity DisorderThe purpose of this study is to determine whether motorcycle drivers with ADHD are at a greater risk for motorcycle accidents, and whether this risk can be mitigated by treatment with methylphenidate. We will evaluate the effectiveness of Methylphenidate on driving performance, among motorcycle drivers, and investigate the correlation between improvement of ADHD symptoms (inattention and impulsivity) and driving performance.
Adherence and Long-term Effect of OROS Methylphenidate (CONCERTA): A Follow-up Study
Attention Deficit Disorder With HyperactivityThe objectives of this study are to investigate: the evolution of ADHD symptoms, remission rate of ADHD, social and school function, and familial relationship; the adherence to CONCERTA, treatment modality, and average treatment duration during the 3-year follow-up period; and the effect of medication on the changes of neuropsychological functioning.