PROJECT SUMMARY The purpose of this study is to investigate the neurobiological mechanisms that link acute alcohol intoxication with cigarette use in young nondaily smokers (ages 21-25). Nondaily smokers experience fewer symptoms of cigarette withdrawal than daily smokers; however, they still experience difficulty quitting. Since smoking cessation before the age of 30 substantially attenuates the long-term health consequences associated with smoking, understanding the factors that motivate cigarette use in young nondaily smokers and developing tailored interventions will be critical for curbing cigarette use and improving public health. The proposed project will use functional magnetic resonance imaging (fMRI) to examine how acute alcohol intoxication impacts brain function and will assess the extent to which alcohol-induced changes in brain function correlate with impulsive choice, cigarette craving, and craving regulation in young adults. Furthermore, we will assess how alcohol-induced changes in brain function, impulsivity, craving, and capacity for craving regulation predict cigarette use over the course of 1 year. This K01 application advances the PI's long-term research goal of establishing an independent line of research examining neurobiological markers that confer risk for future substance use disorder using multimodal neuroimaging techniques. The proposed training plan will enable the PI to develop skills and expertise in five primary areas: 1) design and implementation of longitudinal studies, 2) task-based and resting- state fMRI, 3) advanced statistical methods, 4) the assessment of acute neurobiological responses to drugs and 5) the neurobiological underpinnings of impulsive choice. The training program combines formal coursework with mentorship from experienced consultants who are experts in the proposed areas of training. This project will leverage the intellectual and institutional support at OHSU and in Dr. Nagel's Developmental Brain Imaging Laboratory in order to develop a new line of research that will form the foundation for a career as an independent researcher.