| Introduction | | | | |
| | | | Scientists do not yet fully understand the |
| Alzheimer's disease is a progressive | | | | causes of Alzheimer's disease. There probably |
| condition that damages areas of the brain | | | | is not one single cause, but several factors |
| involved in intelligence, memory, behavior, | | | | that affect each person differently. |
| judgment, and language. It is the most common | | | | |
| form of mental decline in older adults. | | | | |
| Alzheimer's gets worse over time, but the | | | | |
| course of the disease varies from person to | | | | Recent studies indicate that amyloid beta |
| person. Some people may still be able to | | | | protein may cause Alzheimer's disease. In |
| function relatively well until late stages of | | | | healthy people, this protein can cross the |
| Alzheimers disease. Others may lose the | | | | blood-brain barrier (the wall of blood |
| ability to do daily activities in earlier | | | | vessels that feed the brain and regulate the |
| stages. Over time, Alzheimer's disease causes | | | | entry and exit of brain chemicals) and leave |
| severe mental and functional problems and | | | | the brain. In people with Alzheimers disease, |
| eventually results in death. | | | | amyloid beta protein can't pass through that |
| | | | barrier. As more amyloid beta protein |
| | | | accumulates in a person's brain, they become |
| | | | more and more mentally disabled. |
| Causes | | | | |