DESCRIPTION (provided by applicant): This project's over arching aim is to characterize the neurocognitive risks for onset of cigarette smoking and neurocognitive consequences of continued smoking in mid to late adolescence and into the early 20's. Data for this study will be collected from youth (N=910) in an ongoing high-risk-for-alcohol-use-disorder prospective family study who had neurocognitive assessments in early adolescence and who have been well characterized by ongoing assessments at three year intervals since early childhood. The sample will move from late adolescence into the early twenties during the new project period. The high-risk sample and the extensive neurocognitive measures are ideally suited for the aims of the current project, which will evaluate the neurocognitive risks and consequences for smoking onset and continued smoking through secondary analyses. Nicotine initially has beneficial effects on alertness and attention and may engender continued use in adolescents with attention problems. Continued chronic smoking is associated with reduced neurocognitive function in adults especially reduced working memory function, slower reaction times, slower information processing speed and reduced cognitive proficiency. Neural functioning will also be characterized directly via fMRI to examine individual differences in brain functioning in relation to cigarette smoking and changes in brain function over time with chronic cigarette smoking. Differences in neural development will be characterized in the late teens and again two years later in 120 selected youth from the larger study using a working memory cognitive task. Neurocognitive assessments will be carried out at 3 year intervals, and the fMRI protocol is to be administered twice during the grant period. Reduced neurocognitive function appears to be both a risk for and a consequence of smoking and the longitudinal design provides a unique opportunity to assess neurocognitive function before and after smoking onset.