Transcript: For the unprepared, experiencing a migraine aura can be an unsettling and confusing experience.  But today, we understand more than we ever have about auras.  An aura is often a warning sign that a migraine headache is about to begin.  Auras begin up to an hour before the headache starts, and are typically 30 minutes to an hour long.  Although less than 30% of migraine headache sufferers experience an aura, some patients have been known to develop auras after years of migraine headaches, so every migraine sufferer should know about them.  If you don’t know what an aura is like, you might start by looking at paintings by Pablo Picasso.  Patients who have experienced visual auras say that they are “phenomenally similar” to Picasso’s cubist pieces.  It is widely speculated that Pablo Picasso suffered from migraine with aura, and that those auras provided some of the inspiration for his groundbreaking new style of artwork.  Physiologically, an aura is due to changes that take place in the cortex, the outer layer of the brain.  When a person begins to develop an aura, it is believed that activity in nerve cells in one part of the cortex become first become excited and then become depressed. With time the change in activity spreads across the cortex, impairing the function of the body parts controlled by these cells.  Auras can take on many forms, but the most common auras are visual, which produce a change, illusion, or distortion in sight. What is common to most auras is that they move or grow with time. Rarely, patients who experience visual auras will report incredibly detailed hallucinations.  Lewis Carroll, who is best remembered as the author of Alice in Wonderland, was a migraine headache sufferer who famously experienced hallucinogenic auras.  In fact, many of Alice’s bizarre experiences in the book were actually descriptions of auras that Lewis Carroll had experienced.  Sensations of rapidly shrinking or growing larger, double vision, and an impaired sense of time, all colorfully illustrated by Alice’s adventures, are rare migraine aura symptoms.  In fact, they have actually come to be known as Alice in Wonderland Syndrome.  Not all auras are visual.  For some people, an aura manifests itself as numbness or a pins-and-needles sensation in the hand that can move into the arm and tongue.  Other patients experiencing an aura can hear a persistent buzzing sound or even lose their hearing for brief periods of time.  Because auras almost always immediately precede a migraine headache, they can actually help patients to avoid migraine headaches.  Patients with aura can anticipate the onset of a migraine, and use abortive medications to avoid them.  Voiceover: The movies in this series can be viewed in any order.  If you wish to watch these clips in their original sequence, then the next clip is, “Chocolate, Chinese Food & Storm Fronts: Identifying YOUR Headache Triggers,”