Examining Proximal Associations Between Stress, PTSD Symptoms, and Alcohol Use among College Students with Trauma Histories - Alcohol use is a prevalent problem among college students. College students report disproportionately high rates of drinking and heavy episodic drinking (HED; i.e., consuming 5+ drinks among men, consuming 4+ drinks among women in 2 hours) relative to non-college enrolled young adults. College students endure unique stressors in relational, academic, and adjustment-related domains. Stress sensitization theory posits that Individuals with trauma histories may be prone to heightened stress responses to life stressors and experiencing stress can provoke and exacerbate PTSD symptoms. Prior research supports the relationship between PTSD symptoms and alcohol use and between stress and alcohol use; however, there is limited understanding into whether these factors synergistically increase the risk for alcohol use among college students. The self-medication model suggests that individuals with PTSD symptoms are more likely to drink alcohol to manage distress. An integrated stress sensitization and self-medication model would suggest that the risk of alcohol use may be highest among those who experience co-occurring PTSD symptoms and stress. The overall objective of the proposed study is to elucidate the proximal associations between stress, PTSD symptoms, and alcohol use among trauma-exposed college students. The study will identify the interacting effects between daily perceived stress and daily PTSD symptoms utilizing an ecological momentary assessment (EMA) design. No prior research has examined the relationship between college students’ perceived stress, PTSD symptoms, and alcohol use and whether these risk factors interact to predict increased drinking. Guided by stress sensitization theory and the self-medication model, the proposed study will advance the understanding and prevention of alcohol misuse. The specific aims of this proposed study are to: (1) evaluate whether PTSD symptoms and perceived stress temporally relate to alcohol use (any, HED, and number of drinks) and (2) evaluate whether PTSD symptoms moderate the temporal association between perceived stress and drinking. The proposed study will examine these factors in 60 college students with trauma histories utilizing an innovative EMA design. The proposed study is significant because it will identify specific risk factors to address in the prevention and intervention of alcohol use among trauma-exposed college students.