Project Summary: The goal of this study is to investigate the impact of sleep on neurocognitive and daily functioning in people with schizophrenia (SZ). Individuals with SZ display a broad range of neurocognitive impairments that have been identified as major determinants of poor functioning and disability, thus representing an important public health concern and a focal target for interventions. Extensive animal, preclinical and clinical research literatures converge in highlighting the critical role insomnia and sleep disturbances play in degrading neurocognitive functioning. Such sleep disturbances, which have been linked to reduced slow wave sleep oscillations and thalamo- cortical sleep spindles, result in clinical presentations that are in line with the neurocognitive difficulties commonly observed in people with SZ. Consistent with these findings, insomnia and sleep disturbances are highly prevalent in people with SZ. However, despite their chronic and ubiquitous nature, there are scant data on the impact sleep disturbances on neurocognition in SZ and there are no data quantifying their influence on daily functioning. Thus, sleep disturbances remain poorly understood and modeled in SZ, their impact is rarely considered in clinical trials, and they remain largely unaddressed by clinicians. To address this gap in the literature, the primary aim of this study is to characterize sleep in individuals with SZ and quantify its impact on neurocognition and daily functioning. Employing an experimental, within-person, repeated assessment design, we will characterize sleep architecture, duration, and quality along with cognitive, electrophysiological, biomarkers and daily functioning sequalae in 40 individuals with SZ. Participants will first complete a week-long, in-home characterization of sleep duration and quality using actigraphy and a sleep diary. Next, they will complete two overnight polysomnography examinations employing two sleep schedules: 1) undisturbed sleep; and 2) restricted sleep (4 hours). As part of these assessments, participants will provide blood samples for biomarkers analyses and complete EEG-indexed memory tasks pre- and post-sleep, along with a post-sleep battery of neurocognitive functioning. Finally, participants will complete a 36- hour ambulatory assessment using actigraphy and smartphones employing Experience Sampling Method (ESM) to explore the impact of sleep on “real-world” daily functioning including symptoms, emotion regulation, and mood. PublicHealth Relevance Statement:This study will provide experimental characterization of the links between sleep neurocognition and functioning in individuals with SZ, informing the development of treatments of neurocognitive deficits in SZ.