Care2.com | What is dementia? Alzheimer's Society Dementia is caused when the brain is damaged by diseases, such as Alzheimer's disease or a series of strokes. Alzheimer's disease is the most common cause of dementia but not all dementia is due to Alzheimer's. The specific symptoms that someone with ... Alzheimer's and Atherosclerosis of the Brain Remembering to hope | Bancroft this Week |