PROJECT SUMMARY The goal of this R15 Research Enhancement Award is to elucidate the role and impact of executive functioning in relation to the use of cognitive reappraisal as an emotion regulation strategy. Cognitive reappraisal is a key process in cognitive therapies and cognitive behavioral therapy (CBT), the frontline treatment for anxiety and depression, but individuals are not always successful at implementing reappraisal. We propose that executive functioning, a set of higher- order cognitive abilities, may partly underly reappraisal success. This project is innovative in that we will assess reappraisal ability (i.e., success) in a naturalistic context using experience sampling methodology (ESM), a relatively new approach not previously used to study reappraisal ability. Prior research has relied upon in-lab assessment, which has strong internal validity but may lack external validity due to the controlled lab environment and narrow stimulus sets, and limited ability to study the effect of reappraisal in daily life. In addition to these scientific aims, this project emphasizes development of institutional research infrastructure and student training through intentional and embedded training related to ESM and related approaches. With a diverse, well-characterized, community-based sample of 150 adults, we will assess the influence of reappraisal on emotional response to daily life stressors using ESM. We will also examine the relationship between executive functioning and reappraisal ability in daily life. By utilizing both ESM and an established in-lab reappraisal paradigm, we can establish ground truth of the ESM approach to assessing reappraisal ability. If valid, this approach to studying reappraisal could impact future research in this area. Additionally, findings could inform intervention optimization. For example, if specific facets of executive functioning (e.g., limited inhibition or shifting) impair use of reappraisal, intervention may be successfully augmented via the addition of targeted training for executive functioning.