Alzheimer disease is a disorder of the brain. It leads to a loss of the ability to think, reason, and remember. Symptoms can change from day to day, but over time the disease worsens. Alzheimer dementia is when a person is no longer to care for him or herself.

Areas of the Brain Affected by Alzheimer Disease
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The cause is not clear. Brain cells stop working and begin to die. It may be due to a mix of genes, environment, and overall health.

Two known things that play a role are:

  • Neurofibrillary tangles —twisted fibers of a protein called tau fibers inside nerve cells
  • Neuritic plaques —a protein called beta amyloid builds up between nerve cells

These changes often begin in areas of the brain that store memory. This damage may start several years before the first symptoms appear.

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Revision Information

  • Reviewer: EBSCO Medical Review Board Rimas Lukas, MD
  • Review Date: 09/2019 -
  • Update Date: 10/08/2019 -