Multimodal Neurobiological Approaches to Explore the Gene-Environment Interactions in ADHD

In the present project, investigators aim to explore the complex gene-environment interplay in children with ADHD to identify the crucial pathophysiological pathways from genes to the brain. To achieve our objective, investigators will use multimodal neurobiological approaches to effectively resolve the four major challenges in exploring gene-environment interactions on ADHD. 1. investigators will use multiple levels of neurobiological approaches to identify the interactions between monoamine transporter genes and environment on ADHD, including neuropsychology, neuroimaging, and neuroactive metabolites in plasma, which will provide larger effects than clinical diagnosis. 2. investigators will employ correlation analyses to test for the presence of correlations between the monoamine transporter genotypes and the environmental factors. 3. investigators will use both categorical (diagnosis of ADHD) and dimensional (inattention and hyperactivity-impulsivity symptoms of ADHD) approaches to assess the interaction effects between monoamine transporter genes and environment. 4. investigators will conduct interactions with ageitems to model more accurately the effects of age, which may be non-linearly related to the neurobiological basis of ADHD.