An integrative framework of cognitive control and reward modulation in children with ADHD: from brain dynamics to clinical symptoms

Project Summary Attention deficit hyperactivity disorder (ADHD) is one of the most common neurodevelopmental disorders, with prevalence rates ranging from 5-10% globally. With rising diagnosis rates in the last two decades, childhood ADHD has become a significant social and financial burden to affected individuals, families, and society at large. ADHD is characterized by impairments in cognitive control, with adverse life-long consequences for academic and social functioning. Cognitive control requires dynamic engagement of proactive and reactive control processes, and aberrancies in these processes underlie behavioral deficits, including elevated response variability and slow stopping speed. A related line of research suggests that rewards may increase stopping speed and reduce response variability in ADHD, with some individuals even reaching similar performance as typically developing children (TDC). However, the cognitive and brain mechanisms underlying proactive and reactive control, their modulation by reward and relation to clinical symptoms in ADHD are unknown. Here we develop an innovative multi-componential cognitive, neuroscience, and computational framework to address this gap and advance fundamental understanding of dysfunctional brain circuits linking cognitive control and reward systems in children with ADHD. Recent progress in cognitive and computational neuroscience has demonstrated that cognitive control relies on dynamic brain states characterized by dynamic interactions in functional brain circuits. The proposed studies will rigorously test theoretical cognitive and neuroscience models of ADHD by examining reward modulation of proactive and reactive control as well as dynamic brain circuits involving cognitive control, default mode and reward systems in children with ADHD. We will integrate multiple high-impact lines of our ongoing research on cognitive control, children with ADHD, and brain circuit dynamics. Importantly, we will leverage multiple novel computational models to uncover dynamics of cognitive and brain processes. The proposed studies will: (1) investigate how reward modulates proactive and reactive control in children with ADHD, (2) determine how aberrations in reward modulation of proactive and reactive control are related to core clinical symptoms, (3) characterize dynamic brain circuits underlying reward modulation of proactive and reactive control in children with ADHD, (4) determine how reward modulation of dynamic brain circuits involving cognitive control and reward systems are related to core symptoms, (5) identify multivariate cognitive and neurobiological features for classification of childhood ADHD and prediction of core clinical symptoms of ADHD. The proposed studies will facilitate a deeper understanding of cognitive and brain mechanisms underlying reward modulation of cognitive control, which will facilitate developing more effective and precise intervention for childhood ADHD in the future. Our cognitive, neuroscience and computational framework developed here can be widely applied to study many psychiatric disorders that manifest similar cognitive deficits, such as schizophrenia and autism.