A Pathological and Cognitive Study for Participants with Diabetes Lead Investigator: Wei Li Institution : Indiana University Purdue University Indianapolis E-Mail : wl23@iu.edu Proposal ID : 771 Proposal Description: 1. Diabetes is shown as a risk factor for Alzheimer's disease. However, the underlying pathogenesis is largely unknown. The proposed research is going to compare the pathological changes as well as cognition changes in participants with and without diabetes (at the baseline). A successful completion of the proposed project will expedite the process of disclosing the underlying mechanisms of AD pathogenesis. 2. There are several objectives: 2a: to compare the cognitive function changes by using the neuropsychological data along the follow-up for using UDS. 2b. to compare the pathological changes by using MRI and neuropathological data. 2c. to compare the AD biomarker changes by using CSF biomarker data. This project will study the pathological changes in brain structure and AD biomarkers with using a longitudinal study design (2005 to present).