Alzheimer's disease. Series of computed tomography (CT) scans of an axial section through the head of a 74-year-old patient with Alzheimer's disease. The front of the brain (grey) is at the top. Alzheimer's is a neurodegenerative disease and a common cause of dementia in the elderly. It causes brain atrophy (decrease in size), shown here by the enlarged ventricle cavities (black) and the widened white regions. The brain shrinkage caused by Alzheimer's disease leads to memory loss, confusion, personality changes and ultimately death. The cause of Alzheimer's disease is not known and there is no cure.