This 3D animation by The Human Atlas explains the causes and physical affects of Alzheimer's Disease.

The healthy brain is made up of millions of interconnecting nerve cells, called neurons. Neurons constantly communicate with each other by sending signals through tentacle-like connections called axons and dendrites.

The brain of a patient with Alzheimer's disease is much different. The orderly, organized arrangement of nerve cells found in a healthy brain become entangled, full of senile plaques and neurofibrillary tangles. The plaques and tangles interfere with the normal activity between neurons in the area of the brain responsible for intellectual thought.

Alzheimer's disease affects people in different ways. The disease is slowly progressive from onset. Memory loss, confusion, disorientation, and poor judgment are a few of the symptoms of Alzheimer's disease.