PROJECT SUMMARY/ABSTRACT People of Latin American origin are projected to comprise over 28% of the United States (U.S.) population by 2060 and close to 70% of the Latino population is comprised of people of Mexican origin. Racial and ethnic minorities in the U.S., including people of Mexican origin, face higher rates of perceived discrimination and economic hardship. Prior research suggests that exposure to these forms of adversity leads to both higher risk for depression as well as increased allostatic load, or physical wear-and-tear on the body. In contrast, some research in African American samples suggests that ‘resilience,’ or resistance to developing mental health problems under conditions of adversity, may incur a cost of increased allostatic load during young adulthood. It is plausible that this mechanism may also occur for Mexican-origin individuals. This indicates a critical need to examine allostatic load in addition to depression symptoms to test whether some individuals who may appear ‘resilient’ in terms of low depression symptoms exhibit increased allostatic load in young adulthood. The current proposal aims to establish the association between adversity in adolescence and depression symptoms and allostatic load in young adulthood for those of Mexican origin, identify neural mechanisms mediating these associations, and discover protective factors that can mitigate these processes of risk. In this study, the research team proposes to collect a new wave of longitudinal data in the California Families Project (CFP), a longitudinal study that has followed 674 Mexican-origin youth and their families since youth were 10 years old. The study will capitalize on previous waves of longitudinal data collected in the CFP, including multi-informant assessments collected annually from age 10 to 21 and functional MRI data collected when youth were 16 and 19 years old. For this R01, the research team proposes to add a new wave of data collection (age 25 years) to assess allostatic load, current depression symptoms, and self-report of potential protective factors. The research team will test the following specific aims: 1) Examine the association between economic hardship and perceived discrimination experienced during adolescence and depression symptoms and allostatic load in young adulthood. 2) Identify the neural mechanisms through which specific forms of adversity predict depression symptoms and allostatic load in young adulthood. 3) Examine how ethnic identity, familism, parent-child relationship quality, self-esteem, active coping, optimism, and religiosity moderate associations between adversity, neural activity, depression symptoms, and allostatic load. This research will determine how adolescent adversity predicts depression and allostatic load in Mexican-origin young adults, identify neural mechanisms of risk that could be targeted in interventions, and identify protective factors that can mitigate depression risk that could be targeted ...