Project Summary/Abstract Adolescent mental health problems, such as anxiety and depression, have drastically increased over the past decade with major costs to individuals and society. Mental health problems are known to contribute to immediate and long-term stress-related physical health problems. Unfortunately, adolescents exposed to chronic stressors are at an increased risk for developing mental health problems likely due to impairments in emotion regulation, a self-regulatory task of adolescence necessary for coping with stressors. Mindfulness-based interventions (MBIs) have been proposed to ameliorate mental and physical health problems through improvements in mindfulness and emotion regulation difficulties. However, most research on adolescent MBI mechanisms of change has only been conducted at the between-subjects level with cross-sectional data that are subject to low ecological validity. Further, little is known about how MBIs help adolescents to maintain mindfulness and healthy emotion regulation in moments of stress. The use of ecological momentary assessment (EMA) can help to fill these gaps in the literature by providing information about momentary, state-level processes. The purpose of this project is to utilize EMA to understand the extent to which an MBI promotes adolescents’ maintenance of mindfulness and healthy emotion regulation in moments of stress. The specific aims are to (1) characterize, prior to an intervention, the real-time, dynamic relationships between life stressors, state mindfulness, and state emotion regulation difficulties in at-risk adolescents and (2) to investigate the extent to which participation in an MBI compared to a control condition changes these real-time, dynamic relationships. These aims will be tested within the context of a larger, parent randomized controlled trial designed to study an MBI’s feasibility and acceptability as well as its effectiveness for improving maladaptive eating behaviors among at-risk adolescents (11-18y) referred to a community-based mentoring program for being “at-risk for not reaching their full potential.” The current proposal is a novel extension of this trial by adding EMA measurements of mindfulness, emotion regulation difficulties, and life stressors to a sample subset (n=80 of N=160). Multilevel structural equation modeling will be used to investigate the aims. This proposal is designed to advance the candidate’s long-term goal of becoming an independent scientist with advanced methodological and statistical knowledge that can be applied to maximizing the effectiveness of MBIs and contemplative practices for use in communities with chronic stress exposure. The training objectives are to a) develop necessary skills to conduct and analyze EMA, b) gain knowledge about MBI clinical trials with adolescents in high-stress contexts, and c) further understanding of stress-related physiological mechanisms of change in MBIs. Knowledge generated from this proposal will provide...