The healthy brain is a symphony of 100 billion neurons, the actions of each individual brain cell harmonizing into a whole that enables thoughts, movements, memories, or even just a sneeze. But it takes only one dissonant instrument to mar the cohesion of a symphony. When neurons begin to play nonstop, out of tune, and all at once because of disease, trauma, tumor, lack of sleep, or even alcohol withdrawal, the cacophonous result can be a seizure.