In healthy people, all sensations, movements, thoughts, memories, and feelings are the result of signals that pass through billions of nerve cells, or neurons, in the brain. Neurons constantly communicate with each other through electrical charges that travel down axons, causing the release of chemicals across tiny gaps to neighboring neurons. In a person with Alzheimer’s disease changes in the brain destroy this healthy balance. These changes may occur years before the first signs of dementia. This video explores how Alzheimer's changes the brain.
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