The Neuropathology Core's main goal is to obtain, characterize, store and distribute for research, tissue specimens form longitudinally followed dementia patients and control research subjects from the Oregon Alzheimer Disease Center (OADC) Clinical Core. Additional valuable brain donations are provided by selected patients from the State of Oregon and Northwest region. All available specimens from subjects studied by the Center will be obtained and analyzed as rapidly as possible post-mortem. The Neuropathology Core will apply state-of-the-art, standardized protocols and staining methods to characterize the autopsy tissue quantitatively and semi-quantitatively and to render a diagnosis. Approaches used to analyze tissue will include molecular, biochemical, immunological, histochemical and morphometric techniques. These methods will be applied to an increasing number of autopsy specimens from clinically well-characterized individuals including non-demented control subjects followed by the Clinical Core. Data from the brain analysis will be entered into coded data forms, checked for accuracy and completeness and subsequently entered by the Data Core. Tissue will be provided to local and national investigators utilizing these tissues for hypothesis driven research and the development of novel probes and techniques.