PROJECT SUMMARY This application is in direct response to NOT-MH-21-120 dedicated to administrative supplements for COVID- 19 impacted NIMH research. The goal of this administrative supplement application is to request supplemental funding to complete the goals proposed in the first phase (R61) of the parent multi-phase clinical trial study (R61/R33 phased award) to examine the effect of a novel neuromonitoring guided cognitive intervention for targeted enhancement of working memory. The R61 phase of the trial has been on hold for 8 months due to COVID-19 pandemic and resumed in November 2020. The supplemental funding is critical to ensure that the goals proposed in the R61 phase will be accomplished during the no-cost-extension period. The parent multi- phase award is designed so that the transition to the R33 phase of the award is contingent upon meeting go/no-go milestones in the R61 phase. Thus, without completing the goals of the R61 phase, we cannot move on to next phase of the award that is designed to examine the clinical efficacy of the proposed intervention. Per NOT-MH-21-120 instructions, this supplement is within scope of the parent grant. We have exhausted various alternative non-monetary solutions to rescue our protocol from the COVID-19 related disruption. The intervention proposed in the parent grant involves integrating computerized WM training with real- time fNIRS neuromonitoring and neurofeedback to guide the intervention through reinforcement of a strategy that maximizes the engagement of the target WM network. In the R61 phase of the parent R61/R33 grant, we proposed to assess target engagement, effective dose and feasibility. Sixty children with ADHD with WM deficits will be randomized to treatment (N = 30) or control (N = 30) groups. Both groups will be assessed using a set of neuroimaging, clinical and behavioral assessments. Particularly, we will test if the intervention results in normalized activity (reduced hypoactivity) in the frontal-parietal network and improved WM performance during N-back task. If the intervention results in improvement in target engagement and WM performance based on the proposed criteria, we will advance to the R33 phase to test the clinical efficacy of the proposed intervention, versus an active comparison intervention, in a larger sample. The supplement will cover the cost of enrolling and completing data collection/analysis for 16 patients during the no-cost extension period to meet the targets and accomplish the goals proposed in the R61 phase. Validation of the proposed approach will provide a foundation for developing personalized, pathology- focused, cross-diagnostic interventions and could significantly enhance patient outcomes and public health.