Alzheimer's disease is a condition that destroys brain cells. People with this disease slowly lose the ability to learn, function, and remember. It is the most common cause of dementia. Dementia is a loss in mental abilities that is great enough to interfere with daily life.

Areas of the Brain Affected by Alzheimer's Disease
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The cause of Alzheimer's is not yet known. Two factors that may play a role in the development of Alzheimer's disease are:

  • Plaques—Abnormal deposits of a substance called beta amyloid in different areas of the brain
  • Neurofibrillary tangles—Twisted fibers (called tau fibers) within the nerve cells