Risk behaviors can threaten health and safety from both an individual and a public health perspective. They are associated with higher disability, mortality, and national healthcare costs. Among HIV+ individuals, some risk behaviors, such as unprotected sex and needle sharing, can lead to the spread of HIV disease. Other risk behaviors, such as substance use, can adversely affect health. Much of the current literature has focused on the association between psychosocial factors and engagement in risk behavior. However, the neurocognitive mechanisms underlying these complex behaviors remain poorly understood. The prefrontal cortex and associated frontal white matter tracts in the brain that are involved in higher-order, complex neurocognitive processes, often referred to as executive functions, are likely to be involved. Building upon the extant literature, this study will test a novel neurocognitive model, investigating the specific executive functions driving risk behavior. This project will: 1) confirm that risk behaviors represent a unitary construct; 2) identify the underlying executive functions (i.e., attentional control, impulsivity, and reward learning) that predict risk behavior among HIV+ individuals; and 3) show that our novel executive functioning model predicts risk behavior even after accounting for the contributions of demographic and psychiatric factors (e.g., gender, depressive symptoms, anxiety symptoms). Building on the applicant's solid foundation in neuropsychology and demonstrated potential for independent research, this SC2 grant will provide the protected research time and stable research infrastructure necessary to significantly accelerate her work in neuroAIDS. This project represents the first step in developing a track record of independent funding. The innovative research program that this applicant will establish has the potential to improve our understanding of brain-behavior relationships, particularly in HIV, and to inform more successful, cost-effective prevention and intervention efforts for risk behaviors.