Health's Book

Definition

Like all other parts of the body, the brain and central nervous system are made up of cells that ordinarily grow and divide to create new cells as needed. This is usually an orderly process; but when cells lose their ability to grow normally or to die off naturally, they divide too often and produce tumors that are made up of these extra cells.

Symptoms

—Sudden, uncontrolled electrical activity in the brain resulting in characteristic twitching, or spastic, movements that may be accompanied by loss of consciousness.