This is a follow-up study of the ARIC MRI cohort, with repeated semiquantitative MR imaging and cognitive assessments. The study will also take advantage of recent advances in MR imaging and obtain volumetric measurements of selected brain regions and expand upon the baseline cognitive assessment to further characterize neurocognitive functioning. The longitudinal design of the proposed study will fill salient gaps in current understanding of subclinical CVD. Moreover, conducting this study within ARIC takes advantage of ARIC's baseline MRI data, unique African American population, and extensive vascular risk factor data (including new genetic and biochemical factors as well as subclinical markers of both large and small vessel disease), making an efficient study to provide new insights into the incidence, progression, and outcomes associated with subclinical CVD.