The overall goal of this research proposal is to develop and validate proton magnetic resonance (MR) imaging techniques that can identify the neuropathologic bases of cerebral white matter abnormalities in the elderly. The applicant proposes to validate specific correspondences between histopathologic and MR phenomena and between clinical symptomatology and MR. The proposal has two components: 1) postmortem MR imaging of brains from patients with clinical diagnoses of Alzheimer's disease, patients with dementia due to infarction or to Binswanger's disease, and nondemented patients with and without cerebrovascular disease; and 2) antemortem MR imaging in patients with and without dementia, and in patients with and without risk factors for cerebrovascular disease. The relation of MR white matter abnormality to the presence and severity of clinical syndromes such as dementia, arterial hypertension, and labile arterial pressure, as formulated with these investigations, will guide the applicant in the development of novel MR imaging techniques, including diffusion and perfusion imaging.