Stroke and neurodegenerative disorders such as Alzheimer’s disease are among the leading causes of death worldwide and have imposed a heavy economic burden on society. The development of imaging-based biomarkers for the early and accurate diagnosis of them is of critical clinical need. In this research, we seek to: (1) characterize the normal brain features using the UK Biobank imaging data; (2) develop a lesion detection algorithm that separates the lesion tissue from normal brain tissue using Biobank image data; (3) develop an algorithm for the early detection of Alzheimer’s disease using Biobank image data; (4) Investigate the influence of genetic and environmental risk factors to the variations in brain features.