Agatha Lenartowicz - US grants

Project Summary High prevalence rates of attention deficit hyperactivity disorder (ADHD) (5-11% of children 4-17 years), combined with its high societal cost, strong persistence and pernicious effects on quality of life, warrant continued efforts to understand its underlying neural mechanisms. Underscoring this need is the increasing recognition that ADHD is clinically and mechanistically heterogeneous, and that this likely degrades the reliability of putative biomarkers of ADHD. Novel, focused studies that aim to reduce such heterogeneity are needed. In this project, we aim to define a robust, relatively unexplored putative biomarker of visual attention deficits, alpha range (8-12Hz) event-related decrease (ERD), which strongly indexes working memory (WM) deficits in ADHD. Using cutting-edge, concurrent EEG-fMRI recordings, we propose to measure event-related alpha ERD and its associated brain activation and network connectivity during WM encoding. The concurrent recordings allow us to directly test if fluctuations in engagement of attention mechanisms captured by the alpha ERD neurophysiological measures predict fluctuations in WM neural processes. Using this methodology, we aim to: (a) identify neural mechanisms underlying alpha ERD deficits and WM performance in ADHD, and (b) define the clinical features of alpha ERD deficits in ADHD, including its effect on real life outcomes such as academic achievement. Unique to this project, we will sample participants who were previously tested in two large ADHD-EEG studies, recruiting them for a longitudinal follow-up experimental session if they are currently in adolescence (14-18 years). By doing so we aim to (c) characterize the developmental trajectory of attention deficits as captured by alpha ERD in ADHD, as well its impact on the trajectory of clinical and real-life outcomes. The adolescent sample will provide new insight into neural and neurophysiological characteristics of ADHD during this developmental period. The outcome of this research is a clearly defined neural mechanism, alpha ERD, that can be targeted in treatment of WM deficits in ADHD, or in other neuropsychiatric disorders.

Project Summary Attention deficit/hyperactivity disorder (ADHD), a highly prevalent (5-11% of children 4-17 years in 2011) and persistent disorder, is associated with cognitive deficits that contribute to poor educational outcomes in ADHD. Critically, leading treatment strategies in ADHD are ineffective at improving educational outcomes. Lacking, however, is the assessment of attention deficits in real-life contexts, a key piece to understanding how these deficits impede learning opportunities in the moment (such as in the classroom) and, conversely, how they can be supported by making changes within the child?s environment. In this project, we will develop an attention assessment tool using portable electroencephalography (EEG) recordings, performed in real-time in the classroom. As part of Aim 1 we will validate the technique against (a) visual coding of on-task performance (the current standard in the field), (b) simulated classroom recordings, (c) laboratory based metrics of attention, and, (d) scores of academic achievement. In Aim 2, we collect EEG attention metrics across different types of typical classroom activities ? to test if particular context (whole class, small group, individual) and instructional attention management (teacher-managed vs child-managed) preferentially facilitate attention in the classroom in children with attention deficits. The project emphasizes a theoretical shift from laboratory-based to in-classroom evaluation of attention, and underscores the importance of contextual factors that affect real-life outcomes like learning in school. In future studies, we will use the developed tools to, (i) test the efficacy of proposed classroom accommodations for ADHD (e.g., high stimulation, structure, minimal delay/idle time, reward), and (ii) test the feasibility of this tool to improve treatment monitoring by providing more accurate feedback and treatment adherence when adapted for at-home use.