What is Alzheimer’s Disease?

Alzheimer’s disease is a neurological brain disorder that causes problems with memory, thinking skills, and behavior. It was named after a German physician, Aloïs Alzheimer, who first described it in 1906. Dr. Alzheimer was a pioneer in linking the symptoms of what we now call Alzheimer’s disease to the abnormal clumps (amyloid plaques) and tangled bundles of fibers (neurofibrillary tangles or tau) in the brain.

Alzheimer’s disease progresses over time, and because the life span of our population is growing longer, the number of people affected is increasing rapidly. Scientific researchers have made huge strides in understanding Alzheimer’s, offering that effective treatments, and possibly even a cure, are now within reach.

Memory loss is one of the earliest symptoms of Alzheimer’s, along with a gradual decline of other intellectual and thinking abilities (called cognitive functions), and changes in personality or behavior. Alzheimer’s is the most common form of dementia.

Browse this section to learn about the possible causes of Alzheimer’s disease, what happens to the brain as the disease progresses, and the risk factors and symptoms of Alzheimer’s.