We use neuropsychological assessments along with MRI measures of brain structure and function to better understand how cognitive and psychological difficulties develop in adults. We have three overarching research goals: 1) identify the neural mechanisms responsible for HIV-related neuropsychological impairments; 2) reveal the neural mechanisms through which childhood adversity contributes to increased neurocognitive and neuropsychiatric symptoms in HIV+ adults; and 3) investigate the neural, neuropsychological, and behavioral correlates of various types of stress (e.g., childhood adversity, chronic stress) in adults without HIV.