Migraine aura
Sensory phenomena that may occur before a migraine.
Visual auras may include flashing lights, geometric patterns, or distorted vision.
Some people may have aural auras involving hearing sounds (usually buzzing), olfactory auras involving smelling odors not actually present, or tactile auras that present as a premonitory physical sensation.
Auras are caused by unusual activity in the brain.
The auras experienced by migraine sufferers are very similar to those associated with epilepsy