Sleep is important for cognitive well-being, yet many adults do not get enough sleep. Sleep is especially important for selectively strengthening memories that are emotionally salient, associated with rewards, and relevant for future use; and sleep’s effect on memory selectivity may exacerbate some mental disorders. However, the neural mechanisms of sleep-facilitated selectivity are still being identified, and whether the same mechanisms generalize across different cognitive domains such as emotional memory and problem solving is unknown. The current research will examine 1) the interaction and unique contribution of sleep to emotional memory selectivity and problem solving; 2) the neural signatures of sleep’s effect on selectivity; and 3) whether targeted memory reactivation during rapid eye movement sleep similarly facilitates emotional memory selectivity and problem solving. We will record participants’ brain activity using EEG while they sleep in one of four state-of-the-art laboratory bedrooms, allowing us to precisely identify participants’ sleep stages and associated neural signatures. This research will lead to a better understanding of the neural mechanisms of sleep’s effect on cognition, allowing future research to examine the effect of sleep disruption on sleep-facilitated selectivity. The fellowship training plan will enable the applicant to conduct the proposed research and prepare her for a future career as an independent researcher. Through coursework, workshops, and mentorship, the applicant will extend her prior training in problem solving to include expertise in the cognitive neuroscience of sleep and memory, including EEG analysis techniques such as spectral power analysis, sleep spindle detection, and slow- oscillation-spindle coupling. In addition, the training plan provides extensive professional development in areas of academic communication, research management, and research ethics. Results from the proposed research will be widely disseminated in scientific meetings and publications, and will inform novel research questions at the intersection of sleep, memory, and problem solving, providing a solid foundation from which the applicant can launch her independent research career.