What causes auras?

Auras seem to be caused by a wave of electrical signals from your nerves that travel slowly across part of your brain. This wave of electrical impulses leads to that part of the brain becoming less active than usual. This can affect or slow down the part of your body controlled by that section of your brain.

The back of your brain, which controls your eyes, is the part most often affected. This explains why you may have vision problems. When the areas of your brain that are affected are the ones that control how your body feels, you may get numbness in parts of your body.