Search results for "Attention Deficit Disorder With Hyperactivity"
showing 10 items of 141 documents
Time-on-Task in Children with ADHD: An ex-Gaussian Analysis
2013
AbstractAlthough it is widely known that high intra-individual variability (IIV) is a key characteristic of attention deficit/hyperactivity disorder (ADHD), a detailed exploration of the IIV pattern during the time course of a cognitive task has never been carried out. In this study, 30 children with ADHD and 30 controls, were administered the Conners’ Continuous Performance Task (CPT-II). The across-block individual performance of the groups was analyzed using an ex-Gaussian approach, which enabled a clearer understanding of how individual response times (RTs) fluctuate during a task in comparison with conventional measures of central tendency. While the conventional measures showed a sign…
Genetic analysis of reaction time variability: room for improvement?
2013
Background. Increased reaction time variability (RTV) on cognitive tasks requiring a speeded response is characteristic of several psychiatric disorders. In attention deficit hyperactivity disorder (ADHD), the association with RT is strong phenotypically and genetically, yet high RTV is not a stable impairment but shows ADHD-sensitive improvement under certain conditions, such as those with rewards. The state regulation theory proposed that the RTV difference score, which captures change from baseline to a rewarded or fast condition, specifically measures ‘state regulation’. By contrast, the interpretation of RTV baseline (slow, unrewarded) scores is debated. We aimed to investigate directl…
Candidate genetic pathways for attention-deficit/hyperactivity disorder (ADHD) show association to hyperactive/impulsive symptoms in children with AD…
2013
Item does not contain fulltext OBJECTIVE: Because multiple genes with small effect sizes are assumed to play a role in attention-deficit/hyperactivity disorder (ADHD) etiology, considering multiple variants within the same analysis likely increases the total explained phenotypic variance, thereby boosting the power of genetic studies. This study investigated whether pathway-based analysis could bring scientists closer to unraveling the biology of ADHD. METHOD: The pathway was described as a predefined gene selection based on a well-established database or literature data. Common genetic variants in pathways involved in dopamine/norepinephrine and serotonin neurotransmission and genes involv…
Children with autism and attention deficit hyperactivity disorder. Relationships between symptoms and executive function, theory of mind, and behavio…
2018
Abstract Background The underlying mechanisms of comorbidity between autism spectrum disorder (ASD) and attention deficit hyperactivity disorder (ADHD) are still unknown. Executive function (EF) deficits and theory of mind (ToM) have been the most investigated cognitive processes. Aims This study proposed to analyze EF, ToM and behavioral problems in children with ASD + ADHD, ADHD, ASD and typical development (TD). The relationship between ADHD and ASD symptoms with EF, ToM and behavioral problems in children with ASD + ADHD was also explored. Methods and procedures Participants were 124 children between 7 and 11 years old (22 ASD + ADHD, 35 ADHD, 30 ASD, and 37 TD), matched on age and IQ. …
Efficacy and safety of extended-release guanfacine hydrochloride in children and adolescents with attention-deficit/hyperactivity disorder: A randomi…
2014
AbstractGuanfacine extended-release (GXR), a selective α2A-adrenergic agonist, is a non-stimulant treatment for attention-deficit/hyperactivity disorder (ADHD). This study assessed the efficacy (symptoms and function) and safety of dose-optimized GXR compared with placebo in children and adolescents with ADHD. An atomoxetine (ATX) arm was included to provide reference data against placebo. Patients (6–17 years) were randomized at baseline to dose-optimized GXR (0.05–0.12mg/kg/day – 6–12 years: 1–4mg/day; 13–17 years: 1–7mg/day), ATX (10–100mg/day) or placebo for 4 or 7 weeks. The primary efficacy measure was change from baseline in ADHD Rating Scale version IV (ADHD-RS-IV). Key secondary me…
Extended-release guanfacine hydrochloride in 6-17-year olds with ADHD: a randomised-withdrawal maintenance of efficacy study.
2015
Background Extended-release guanfacine hydrochloride (GXR), a selective α2A-adrenergic agonist, is a nonstimulant medication for attention-deficit/hyperactivity disorder (ADHD). This phase 3, double-blind, placebo-controlled, randomised-withdrawal study evaluated the long-term maintenance of GXR efficacy in children/adolescents with ADHD. Methods Children/adolescents (6–17 years) with ADHD received open-label GXR (1–7 mg/day). After 13 weeks, responders were randomised to GXR or placebo in the 26-week, double-blind, randomised-withdrawal phase (RWP). The primary endpoint was the percentage of treatment failure (≥50% increase in ADHD Rating Scale version IV total score and ≥2-point increase …
Prospective relationships of ADHD symptoms with developing substance use in a population-derived sample
2011
BackgroundClinically ascertained reports suggest that boys and girls with attention deficit hyperactivity disorder (ADHD) may differ from each other in their vulnerability to substance use problems.MethodA total of 1545 Finnish adolescents were assessed for DSM-IV-based ADHD symptoms by their parents and classroom teachers using standardized rating scales at age 11–12 years. At age 14, substance use disorders and psychiatric co-morbidity were assessed with the Semi-Structured Assessment for the Genetics of Alcoholism, providing DSM-III-R/DSM-IV diagnoses for Axis I disorders. At age 17.5, substance use was assessed by multi-item questionnaire.ResultsAlthough baseline ADHD symptoms were less…
Meta-analysis of genome-wide association studies of attention-deficit/hyperactivity disorder
2010
Contains fulltext : 87688.pdf (Publisher’s version ) (Closed access) OBJECTIVE: Although twin and family studies have shown attention-deficit/hyperactivity disorder (ADHD) to be highly heritable, genetic variants influencing the trait at a genome-wide significant level have yet to be identified. As prior genome-wide association studies (GWAS) have not yielded significant results, we conducted a meta-analysis of existing studies to boost statistical power. METHOD: We used data from four projects: a) the Children's Hospital of Philadelphia (CHOP); b) phase I of the International Multicenter ADHD Genetics project (IMAGE); c) phase II of IMAGE (IMAGE II); and d) the Pfizer-funded study from the…
Corpus Callosum Morphology in Attention Deficit-Hyperactivity Disorder: Morphometric Analysis of MRI
1991
Although behavioral evidence provides support for the notion that attention deficit-hyperactivity disorder (ADHD) is related to central nervous system dysfunction, there is little direct evidence to reveal which neurometabolic systems or brain structures are involved. Recent magnetic resonance imaging (MRI) studies suggest that, compared to nondisabled controls, ADHD children may have a smaller right frontal region. Morphometric analysis of MRI scans was used in this exploratory study to determine whether correlated regional variation might exist in the corpus callosum of children with ADHD. While all MRI scans were judged to be clinically normal, morphometric analysis revealed that, compa…
Comorbidity between obesity and attention deficit/hyperactivity disorder: Population study with 13–15-year-olds
2006
Objective: This study analyzes whether obese children have a higher risk of attention deficit/hyperactivity “characteristics” (AD/HD) than do children with other nutritional states. Method: This study included 35,403 participants from 486 community schools. They completed the AD/HD scale of the Strengths and Difficulties Questionnaire (SDQ) and were weighed and measured. 2879 of the participants were obese and 78 were morbidly obese (BMI >40). Results: A discrete, nonsignificant, increment was found in the AD/HD characteristics of male participants with morbid obesity, as compared with the other nutritional states. Among morbidly obese females, the prevalence of AD/HD characteristics was sl…