Treatment studies to date have shown pre-to-post changes in reading circuits with evidence-based remediation of reading disability (RD), establishing a neural signature of successful treatment outcome. However, insight into the neurobiological mechanisms by which treatment produces these changes requires monitoring modulations of key brain regions throughout the course of treatment. Moreover, in any cohort some RD children with highly similar profiles on standardized testing at the beginning of intervention will show large gains and others will not. In the previous grant-cycle we employed multimodal neuroimaging before, during, and after an in-school reading intervention and identified novel neurocognitive pre-treatment factors and dynamic brain/behavior changes that predict individual differences in treatment responsiveness. In the new cycle, we maintain the overarching goal of understanding variation in response to reading remediation in RD learners with dynamic brain/behavior tracking designed to yield novel insights into how remediation modifies brain organization for reading, and why it fails to do so adequately for some RD children, but in the proposed continuation, we leverage the discoveries from the initial phase (the how and why) to next examine what might constitute a more effective neurocognitive focus for treatment in minimal-responders to conventional content. With pre-learning fMRI/MRS and frequent fNIRS/EEG tracking and with both short-term adaptive learning experiments and longer-term Educational Technology based learning programs we vary emphasis on orthographic, phonological, and component process training as we seek to match learning content to individual differences in neurocognitive organization for these component processes. Project Summary/Abstract Page 6 The proposed research examines the neurocognitive bases of treatment response to evidence-based learning programs for reading remediation. We use pre and post treatment neuroimaging and frequent neuroimaging during the course of treatment 1) to gain new insights into how treatment modulates brain organization for literacy, language learning, and remediation; 2) why it fails todo so for some children, and 3) what might constitute a more beneficial focus in minimal-responders. The proposed research represents a key step towards the development of comprehensive and mechanistic models of the neural underpinnings of typical and atypical reading development.