a warning that precedes neurological dysfunction
Yeah, and you thought that auras were New Age psychic bullshit, didn't you?
This is a more specialized, medical definition, but it's for real. About 50% of epileptics have auras. That means they know somehow that they're going to have a seizure before the seizure hits.
As you might imagine, this kind of aura can be a life-saver. I know, because I'm an epileptic, and I'm fortunate enough to have an aura myself.
Every aura is different. Some people smell a smell; other feel a feeling. I see a point of light, shining all colors of the spectrum. I even wrote a poem about it.