PROJECT SUMMARY In response to the NIH’s (RFA-AG-24-029) interest in understanding the role of immigration on life course health and aging, the proposed study aims to examine how older immigrants’ cognitive health is shaped by cognitive reserves and social interactions in the context of senior housing. Foreign-born older immigrants are at higher cognitive health risks than community-dwelling counterparts due to low cognitive reserves and immigration-related challenges. Additionally, many older immigrants who reside in ethnically concentrated senior housing experience both positive and negative social interactions, which may directly impact cognitive health and also modify the impact of cognitive reserves on cognitive health. Using the compensatory reserve hypothesis and resource substitution theory as the theoretical framework of the study, we will examine the independent and interactive effects of cognitive reserves (e.g., education and acculturation) and social interactions (e.g., bonding, bridging, and bullying) on cognitive health. Three specific aims of the study include: (1) to examine the effect of cognitive reserves on cognitive health, (2) to examine the effect of social interactions (bonding, bridging, and bullying) on cognitive health, and (3) to examine whether the impact of cognitive reserves on cognitive health will be modified by social interactions. Given the distinct but related nature of the constructs in each domain, we will consider the interactions within each domain (e.g., education X acculturation, bonding X bullying) and across the domains (e.g., education X bridging, acculturation X bullying). To pursue the proposed aims, this study will focus on older Korean immigrants living in subsidized senior housing in Los Angeles. In partnership with Front Porch, a community service organization that manages affordable housing in the greater Los Angeles area, we will recruit approximately 300 Korean American residents from four subsidized senior housing facilities with a high proportion of Korean American residents (60 to 80 participants at each site). Data will be collected by using both conventional survey instruments and the social network analysis (SNA) name-generator approach to measure unique indicators of social interactions (e.g., in-degree centrality, effective size, structural hole, and outdegree density) and more in-depth patterns of social interactions. Survey, cognitive assessment, and sociometric data will be used to pursue the proposed aims. Using an explanatory sequential mixed-methods approach, a series of focus groups with residents, family members, and housing staff will be followed to discuss strategies to translate study findings into practice. By enhancing the knowledge of the role of cognitive reserves and social interactions in shaping older immigrants’ cognitive health, this R21 study will respond to the social and cognitive health needs of older ethnic immigrants in underserved communities and build a grou...