Migraine aura symptoms include temporary visual or other disturbances that usually strike before other migraine symptoms — such as intense head pain, nausea, and sensitivity to light and sound.

Migraine aura usually occurs within an hour before head pain begins and generally lasts less than 60 minutes. Sometimes migraine aura occurs with little or no headache, especially in people age 50 and older.

Visual signs and symptoms

Most people who have migraine with aura develop temporary visual signs and symptoms. which tend to start in the center of the field of vision and spread outward. These might include:

• Blind spots (scotomas), which are sometimes outlined by simple geometric designs
• Zigzag lines that gradually float across your field of vision
• Shimmering spots or stars
• Changes in vision or vision loss
• Flashes of light

Other disturbances

Other temporary disturbances sometimes associated with migraine aura include:

• Numbness, typically felt as tingling in one hand or on one side of your face that may spread slowly along a limb
• Speech or language difficulty
• Muscle weakness

The cause of migraine with aura isn't entirely understood. There is evidence that the migraine with visual aura is like an electrical or chemical wave that moves across the part of your brain that processes visual signals (visual cortex) and causes these visual hallucinations.

Many of the same factors that trigger migraine can also trigger migraine with aura, including stress, bright lights, some foods and medications, too much or too little sleep, and menstruation.

Although no specific factors appear to increase the risk of migraine with aura, migraines in general seem to be more common in people with a family history of migraine. Migraines are also more common in women than in men.

People who have migraine with aura are at a mildly increased risk of stroke.