Objectives: To determine ADHD research priorities from the perspective of ADHD professionals internationally.
Method: A two-stage modified Delphi design was used. In Stage 1 (qualitative), participants listed research questions relating to ADHD that they perceived to be most important ( = 132).
Importance: Large-scale genome-wide association studies (GWAS) should ideally inform the development of pharmacological treatments, but whether GWAS-identified mechanisms of disease liability correspond to the pathophysiological processes targeted by current pharmacological treatments is unclear.
Objective: To investigate whether functional information from a range of open bioinformatics datasets can elucidate the relationship between GWAS-identified genetic variation and the genes targeted by current treatments for psychiatric disorders.
Design, Setting, And Participants: Associations between GWAS-identified genetic variation and pharmacological treatment targets were investigated across 4 psychiatric disorders-attention-deficit/hyperactivity disorder, bipolar disorder, schizophrenia, and major depressive disorder.
Key event-related potentials (ERPs) of perceptual decision-making such as centroparietal positivity (CPP) elucidate how evidence is accumulated toward a given choice. Furthermore, this accumulation can be impacted by visual target selection signals such as the N2 contralateral (N2c). How these underlying neural mechanisms of perceptual decision-making are influenced by the spatial congruence of distractors relative to target stimuli remains unclear.
View Article and Find Full Text PDFBackground: Inter-individual variability in neurobiological and clinical characteristics in mental illness is often overlooked by classical group-mean case-control studies. Studies using normative modelling to infer person-specific deviations of grey matter volume have indicated that group means are not representative of most individuals. The extent to which this variability is present in white matter morphometry, which is integral to brain function, remains unclear.
View Article and Find Full Text PDFDifficulties in executive functioning (EF) can result in impulsivity, forgetfulness, and inattention. Children living in remote/regional communities are particularly at risk of impairment in these cognitive skills due to reduced educational engagement and poorer access to interventions. This vulnerability has been exacerbated by the COVID-19 pandemic and strategies are needed to mitigate long-term negative impacts on EF.
View Article and Find Full Text PDFImportance: The use of evidence-based standardized outcome measures is increasingly recognized as key to guiding clinical decision-making in mental health. Implementation of these measures into clinical practice has been hampered by lack of clarity on what to measure and how to do this in a reliable and standardized way.
Objective: To develop a core set of outcome measures for specific neurodevelopmental disorders (NDDs), such as attention-deficit/hyperactivity disorder (ADHD), communication disorders, specific learning disorders, and motor disorders, that may be used across a range of geographic and cultural settings.
Background: Autistic traits are often reported to be elevated in children diagnosed with attention-deficit/hyperactivity disorder (ADHD). However, the distribution of subclinical autistic traits in children with ADHD has not yet been established; knowing this may have important implications for diagnostic and intervention processes. The present study proposes a preliminary model of the distribution of parent-reported ADHD and subclinical autistic traits in two independent samples of Australian children with and without an ADHD diagnosis.
View Article and Find Full Text PDFObjective: Growing evidence suggests digital interventions may provide neurocognitive benefits for children with ADHD. This study aimed to investigate the efficacy of a digital attention intervention in children with ADHD.
Method: In this double-blind randomized controlled trial 55 children with ADHD (5-9 years) were allocated to the intervention ( = 28) or control program ( = 27).
Exercise is known to benefit motor skill learning in health and neurological disease. Evidence from brain stimulation, genotyping, and Parkinson's disease studies converge to suggest that the dopamine D2 receptor, and shifts in the cortical excitation and inhibition (E:I) balance, are prime candidates for the drivers of exercise-enhanced motor learning. However, causal evidence using experimental pharmacological challenge is lacking.
View Article and Find Full Text PDFObjective: Reward-based eating drives are putative mechanisms of uncontrolled eating implicated in obesity and disordered eating (e.g., binge eating).
View Article and Find Full Text PDFAttention-deficit/hyperactivity disorder (ADHD; also known as hyperkinetic disorder) is a common neurodevelopmental condition that affects children and adults worldwide. ADHD has a predominantly genetic aetiology that involves common and rare genetic variants. Some environmental correlates of the disorder have been discovered but causation has been difficult to establish.
View Article and Find Full Text PDFDespite the abundance of research evaluating working memory training outcomes in children, few studies have examined the underlying cognitive mechanisms. This study aimed to contribute understanding by exploring whether (maximum span) and/or (basic and cognitive processing speeds), two proposed cognitive mechanisms, are associated with children's working memory performance immediately and 6-months post-intervention. We used data from a previous trial in primary school children (7-11 years) who completed working memory training (n = 52) or an active control (n = 36), comprising 10 sessions (each 20-minutes) in class over two weeks.
View Article and Find Full Text PDFCommon variants account for most of the estimated heritability associated with autism spectrum disorder (autism). Although several replicable single nucleotide polymorphisms (SNPs) for the condition have been detected using genome-wide association study (GWAS) methodologies, their pathophysiological relevance remains elusive. Examining this is complicated, however, as all detected loci are situated within non-coding regions of the genome.
View Article and Find Full Text PDFRecent years have seen a surge in the use of diffusion MRI to map connectomes in humans, paralleled by a similar increase in processing and analysis choices. Yet these different steps and their effects are rarely compared systematically. Here, in a healthy young adult population ( = 294), we characterized the impact of a range of analysis pipelines on one widely studied property of the human connectome: its degree distribution.
View Article and Find Full Text PDFThe capability to generate induced pluripotent stem cell (iPSC) lines, in tandem with CRISPR-Cas9 DNA editing, offers great promise to understand the underlying genetic mechanisms of human disease. The low efficiency of available methods for homogeneous expansion of singularized CRISPR-transfected iPSCs necessitates the coculture of transfected cells in mixed populations and/or on feeder layers. Consequently, edited cells must be purified using labor-intensive screening and selection, culminating in inefficient editing.
View Article and Find Full Text PDFIntroduction: Children and adolescents are increasingly prescribed antipsychotic medications off-label in the treatment of behavioural disorders. While antipsychotic medications are effective in managing behavioural issues, they carry a significant risk of adverse events that compromise ongoing physical health. Of particular concern is the negative impact antipsychotic medications have on cardiometabolic health.
View Article and Find Full Text PDFBackground: Despite the known benefits of accurate and timely diagnosis for children with attention-deficit hyperactivity disorder and autism spectrum disorders (autism), for some children this goal is not always achieved. Existing research has explored diagnostic delay for autism and attention-deficit hyperactivity disorder only, and when attention-deficit hyperactivity disorder and autism co-occur, autism has been the focus. No study has directly compared age at diagnosis and diagnostic delay for males and females across attention-deficit hyperactivity disorder, autism and specifically, attention-deficit hyperactivity disorder + autism.
View Article and Find Full Text PDFPrevailing frameworks propose that a key feature of attention-deficit/hyperactivity disorder (ADHD) is lower motivation. An important component of motivation is the willingness to engage in cognitively or physically effortful behavior. However, the degree to which effort sensitivity is impaired in ADHD has rarely been tested, and the efficacy of stimulant medication in ameliorating any such impairments is unclear.
View Article and Find Full Text PDFBackground: Attention deficit hyperactivity disorder (ADHD) in adults is strongly associated with psychiatric comorbidity and functional impairment. Here, we aimed to use a newly developed online cognitive battery with strong psychometric properties for measuring individual differences in three cognitive mechanisms proposed to underlie ADHD traits in adults: 1) attentional control - the ability to mobilize cognitive resources to stop a prepotent motor response; 2) information sampling/gathering - adequate sampling of information in a stimulus detection task prior to making a decision; and 3) shifting - the ability to adapt behavior in response to positive and negative contingencies.
Methods: This cross-sectional and correlational study recruited 650 adults (330 males) aged 18-69 years (M = 33.
Older adults exposed to enriched environments (EEs) maintain relatively higher levels of cognitive function, even in the face of compromised markers of brain health. Response speed (RS) is often used as a simple proxy to measure the preservation of global cognitive function in older adults. However, it is unknown which specific selection, decision, and/or motor processes provide the most specific indices of neurocognitive health.
View Article and Find Full Text PDFDeficits in effective executive function, including inhibitory control are associated with risk for a number of psychiatric disorders and significantly impact everyday functioning. These complex traits have been proposed to serve as endophenotypes, however, their genetic architecture is not yet well understood. To identify the common genetic variation associated with inhibitory control in the general population we performed the first trans-ancestry genome wide association study (GWAS) combining data across 8 sites and four ancestries (N = 14,877) using cognitive traits derived from the stop-signal task, namely - go reaction time (GoRT), go reaction time variability (GoRT SD) and stop signal reaction time (SSRT).
View Article and Find Full Text PDFUncovering the molecular mechanisms of autism spectrum disorder (autism) necessitates development of relevant experimental models that are capable of recapitulating features of the clinical phenotype. Using non-integrative episomal vectors, peripheral blood mononuclear cells derived from three unrelated individuals diagnosed with autism were reprogrammed to induced pluripotent stem cells (iPSCs). The resultant lines exhibited the expected cellular morphology, karyotype, and evidence of pluripotency.
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