It’s 10:18am and you’re at the office. You’ve finally found a quiet moment to catch up on email, when you realize you can’t see the computer clearly. Dark blotches are covering parts of the screen, and lights seem to float in front of your eyes. You’ve learned by now—these annoying lights are an aura, the first sign you’re about to get a migraine.
Soon, the headache itself will hit, but before that happens, you could experience visual disturbances that include blind spots, shimmering lights, stars, or even rainbow colors.
According to the National Headache Foundation, about 20% of migraine sufferers experience “aura,” which is often a warning sign that a migraine attack is coming.
The Cut interviewed several women on what exactly this feels like, with one woman describing it as “darkness creeping in on the edge of my vision, like sand covering my eyes,” while another’s first experience of aura was “looking at the TV and not really seeing anything.”
While auras don’t hurt, they can be alarming—after all, losing your sight, even temporarily, is scary. That’s why we’re walking through this common migraine stage and explaining it you.
When do auras happen?
Aura symptoms typically crops up shortly before a full-on migraine headache hits.
According to the International Headache Society’s ICHD-3, an officially recognized guide to headaches, each individual aura symptom can last up to an hour, but can also be over in just a few minutes. So, if you have three different aura symptoms, you could experience aura for three hours, for example.
The scientific term for the period before a migraine headache strikes is known as the “prodrome.” It can last from a few hours to even a few days. It can also give you painless symptoms, like trouble sleeping and irritability, but these aren’t the same thing as aura. Auras tend to have a more defined duration (shorter than the prodrome) and more specific visual and sensory symptoms.
Migraine with aura is a distinct type of migraine with a unique diagnosis and treatment options.
That said, states the American Migraine Foundation, even if you have migraines with aura, it doesn’t mean you’ll notice an aura every single time you get a migraine.
What causes auras?
So, what are common aura causes? Well, doctors aren’t 100% sure what causes migraines in general, though they have a theory.
For unclear reasons, in patients with migraines, nerves fire throughout the brain in a wave called a cortical spreading depression. This leads to changes in your brain’s blood vessels and inflammation which ultimately causes the headache pain.
When it comes to aura in particular, the scientific journal Cephalalgia says it’s possible that when the cortical spreading depression moves across your brain in a wave, it affects the areas that control your senses, like the occipital cortex, which processes vision. While this sounds scary, cortical spreading depression itself is not dangerous.
It’s most common for this to cause strange visual disturbances. However, since some people also have sensory, motor, and language issues with aura, it’s likely that other parts of the brain are involved, too, notes the scientific journal.
Types of Auras
In the IDHC-3, the International Headache Society breaks down “migraine with aura,” or “classic migraine,” into four migraine types. Please note that the first one on the list — migraine with typical aura — is the most common. The following three are exceedingly rare and the symptoms (such as not being able to move half your body) might actually indicate other conditions that you should speak to a doctor about.
1. Migraine with typical aura
- blind spots, sometimes in geometric patterns
- flashing lights
- loss of vision or vision changes
- stars or shimmering spots
Migraine with typical aura can also cause sensory disturbances, like numbness or pins and needles that move slowly from one part of the body to another, or across the face or tongue, according to ICHD-3.
As Current Pain and Headache Reports points out, it’s possible to have migraines with typical aura with or without a headache. Usually, you’ll get a severe migraine headache within an hour of your aura, but sometimes the headache never shows up at all.
2. Migraine with brainstem aura
Migraines with brainstem aura, sometimes referred to as “basilar artery migraine” or “basilar-type migraine,” causes less common symptoms. According to the American Migraine Foundation, in addition to the typical visual and sensory symptoms, people who suffer from migraines with brainstem aura can experience:
- double vision
- ringing ears or trouble hearing
- speech and language issues, like trouble speaking or understanding others
- trouble with coordination
Like other aura symptoms, they usually go away completely within 60 minutes.
3. Hemiplegic migraine
“Plegic” means “paralysis,” and hemiplegic migraine sufferers can get all of the above aura symptoms, plus short-term motor weakness or paralysis on one side of their body. The American Migraine Foundation notes that this rare type of migraine can be tough to diagnose, because it can be easy to mistake for a stroke or seizure.
Hemiplegic migraines can run in your family, and doctors have discovered genes that transmit the condition, but you can also get them even if none of your family members do.
Unlike other aura symptoms which only last for about an hour, the weakness and paralysis you get with hemiplegic migraines typically can last up to 72 hours (or in rare cases, it can last for weeks).
4. Retinal migraine
Retinal migraine is another rare subtype of migraines with aura. Often called “ocular migraines,” retinal migraines temporarily cause partial or total blindness in just one eye at a time. Mayo Clinic notes that, since temporary blindness in one eye is usually caused by other medical conditions, it’s also easy to misdiagnose this type of migraine.
What are aura symptoms?
The most common signs are visual symptoms like:
- blind spots
- bright or flashing lights
- partial vision loss
- seeing zigzag lines
- total vision loss
- tunnel vision
In Refinery29, migraine sufferers described these visual disturbances as everything from “a small circle… that's completely blurry and surrounded by a ring of bright, moving rainbow light” to “a shimmery patch with a zigzag outline,” to “shimmering, shaking, white/yellow lights on the outskirts of my field of vision.” For one person, it means looking at a phone and “half the letters disappear.”
Beyond the visual symptoms, aura can cause numbness and tingling, trouble with talking or understanding language, and weak muscles, says Mayo Clinic.
Aura is just one aspect of migraines, and not everyone experiences it, so it’s useful to read up on other migraine symptoms to help you understand your own migraine patterns.
Are auras dangerous?
Aura is just one stage in a migraine attack, and like other migraine symptoms, the symptoms typically go away completely once the migraine passes. But, even though aura doesn’t hurt, it can be a scary experience—especially if you don’t know what it is.
Some types of aura can cause long-term health effects. For example, retinal migraine, can cause long-term blindness in one eye, reports ICHD-3. Though, that’s rare.
Further, there is some evidence connecting migraine with aura to strokes, and even other cardiovascular diseases, according to an article in the scientific journal Nature Reviews Neurology. With that said, the odds of a healthy young person getting a stroke is very rare.
How do you diagnose auras?
Since auras can cause such a broad range of systems, and sometimes don’t even give you a headache, it’s no wonder that it’s not easy to get the right diagnosis.
That’s why it’s so important to speak to a doctor who understands migraines and can recognize symptoms that are easy to mistake for other conditions.
If you think you might have migraines with aura, it can be helpful (for you, and for your doctor) to keep a headache diary.
We recommend taking note of:
- When your migraine started
- Which medications you used to alleviate the pain (and how effective they were)
- What triggers you think were involved in your attack
A doctor can't really see your migraine symptoms, so keeping a record can make it easier for them to tell what’s going on, and help you get diagnosed and treated faster.
How do you prevent auras?
There is no specific migraine treatment to stop or prevent aura, according to Mayo Clinic, although you may be able to soothe some of your symptoms with medications, like aura-related nausea, for example.
That said, it is possible to stop a migraine from progressing or make it less extreme if you catch and treat it during the prodrome or aura phase. Your doctor can talk with you about medications—both acute pain relief and preventive—that can help.
Once the aura begins, you may also be able to avoid or alleviate your migraine by staying in a quiet, dark room, avoiding bright sounds, loud noises, or your own specific migraine triggers.
The information provided in this article is not a substitute for professional medical advice, diagnosis, or treatment. You should not rely upon the content provided in this article for specific medical advice. If you have any questions or concerns, please talk to your doctor.
*Photo by [Anthony Tran on Unsplash](https://unsplash.com/photos/vXymirxr5ac)*