Understanding Alzheimer's Disease: What You Need to Know

Words to know

Alzheimer’s disease

(pronounced Allz-high-merz duh-zeez)
A disease that causes large numbers of nerve cells in the brain to die. These changes make it hard for a person to remember things, have clear thinking, and make good judgments. The symptoms begin slowly and get worse over time.

Clinical trial

(pronounced klin-uh-kuhl try-uhl)
A research study to find out if new treatments are safe and effective. Healthy people and people with Alzheimer’s disease can choose to take part in a clinical trial.


(pronounced dee-presh-uhn)
A serious medical illness that can be treated. Some signs of depression are:

  • feeling sad for more than a few weeks at a time
  • having trouble sleeping
  • losing interest in things you like to do

Depression can cause people to be confused and forgetful.

Mild cognitive impairment

(pronounced mild kog-ni-tiv im-pair-ment)
Also called MCI. It is a medical condition that causes people to have more memory problems than other people their age. The signs of MCI are not as severe as those of Alzheimer’s disease.

Publication Date: June 2011
Page Last Updated: July 29, 2016