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Alzheimer's Disease Health Center

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Glossary of Alzheimer's Disease Terms


Blood-brain barrier: The selective barrier that controls the entry of substances from the blood into the brain.

Blood tests: A series of tests routinely done on blood to look for abnormalities associated with various diseases and conditions.

Brain: Along with the spinal cord, the brain makes up the central nervous system. It is the center of thought and emotion. It's responsible for the coordination and control of bodily activities and the interpretation of information from the senses.

Calcium: An element taken in through the diet that is essential for a variety of bodily functions, such as the communication between nerves, muscle contraction, and proper heart function. Imbalances of calcium can lead to many health problems and can cause nerve cell death.

Calcium channel blocker: A drug that blocks the entry of calcium into cells, thereby reducing activities that require calcium, such as nerve cell communication. Calcium channel blockers are used primarily in the treatment of certain heart conditions but are being studied as potential treatments for Alzheimer's disease.

Caregiver: The primary person in charge of caring for an individual with a serious illness, such as Alzheimer's disease; usually a family member or a designated health care professional.

Care planning: A written action plan containing strategies for delivering care that addresses an individual's specific needs or problems.

Case management: A term used to describe formal services planned by care professionals.

Cell: The fundamental unit of all organisms; the smallest structural unit capable of independent functioning.

Central nervous system (CNS): One of the two major divisions of the nervous system. Composed of the brain and spinal cord, the CNS is the control network for the entire body.

Cerebral cortex: The outer layer of the brain, consisting of nerve cells and the pathways that connect them. The cerebral cortex is the part of the brain in which thought processes take place. In Alzheimer's disease, nerve cells in the cerebral cortex degenerate and die.

Cerebrospinal fluid (CSF): The fluid that fills the areas surrounding the brain and spinal cord.

Chest X-ray (CXR, chest film): An image on film of the structures of the chest (heart, lungs, and bones); the procedure to get the image uses small amounts of radiation.

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