Migraine isn’t just a bad headache. It’s a neurological condition that causes intense head pain along with other symptoms. Migraine symptoms often include:
- nausea
- vomiting
- neck pain
- mood changes
- numbness
- tingling
- sensitivity to light
- sensitivity to sound
About a third of people who have migraine also experience auras just before some of their episodes.
Auras can signal an impending attack and help you seek treatment to ease the worst of the headache. An increase in migraine attacks with aura can be a sign of an underlying cause.
Migraine symptoms are similar whether you have an aura before the episode or not — the difference is the phase just before the migraine episode begins. For people who experience auras before an attack, visual symptoms like zigzag lines and spots are most common. Other symptoms may include:
- slurred speech
- difficulty speaking
- a prickling or tingling sensation
- visual disturbances
- partial vision loss
Migraine can be difficult to manage and cause debilitating pain. Auras add to the discomfort, causing issues even before a migraine episode starts. On their own, migraine auras are a concern. Studies have shown that the presence of aura in migraine attacks can be a sign of more serious neurological conditions, including a twofold increased risk for ischemic stroke.
No one exactly knows why auras develop before migraine attacks, but a leading theory is that they’re the result of cortical spreading depression and potentially vascular changes.
Cortical spreading depression is a phenomenon present in a variety of neurological conditions. A triggering event, either electrical or mechanical, causes a disruption in the brain’s normal electric activity. Neurons power the brain’s signals, but in the case of cortical spreading depression, a wave of depolarization affects electric activity in the brain. Spreading depression can affect one or more regions of the brain.
Migraine auras may begin in the occipital lobe of the brain — affecting vision — then travel to areas of the brain that trigger headache pain.
More research is needed to learn exactly how cortical spreading depression and auras are related, but there are a number of triggers that have been linked to both this phenomenon and auras. An increase in these triggers could have the potential to increase the frequency of migraine with aura.
Underlying medical conditions
There are certain conditions that can make you more susceptible to both cortical spreading depression and migraine, potentially increasing aura occurrence. These include:
Environmental triggers
A number of environmental triggers are also known to prompt these issues. These include:
- bright lights
- strong smells
- extreme heat or cold
- weather changes
Hormonal changes
Men who have migraine are more likely to experience aura than women who have migraine. For women, migraine and auras have been noted to occur more during periods of major hormonal shifts, like:
- menstrual cycles
- pregnancy
- puberty
- menopause
Brain function and blood flow
Cortical spreading depression might impact blood flow and blood vessels in the brain. While extreme changes in blood flow are dangerous and aren’t a part of migraine, more research is needed to fully understand the role of changing electrical signals in the brain to both aura and migraine development.
Stress
Stress is a well-known cause of migraine with and without aura and a host of other neurological conditions. Emotional stress isn’t the only type of stress that can impact the prevalence of migraine with aura, though. Metabolic stress like hypoglycemia can also trigger these events, as well as sleep deprivation.
There’s a lot that’s unknown about why migraine with aura or cortical spreading depression develop. It’s unclear at the moment whether impending migraine and blood flow changes itself triggers electrical changes in the brain or whether the electrical changes are the cause of blood flow changes and migraine.
Prophylactics
Some medications, such as acetazolamide, can help control fluid and possibly the electrical balance in the brain and possible head off auras and other symptoms associated with cortical spreading depression. Acetazolamide is a diuretic (water pill) that prevents excess fluid accumulation and helps to regulate ion channel function and negative electrical impulses.
Seizure medications and beta-blockers
Some seizure medications like topiramate and valproate, or beta-blockers like propranolol, have also been used to prevent migraine with aura. These medications are also sometimes used to treat certain types of migraine, possibly pointing to a connection between treating both spreading depression and migraine with auras.
If you regularly have migraine attacks, you should see a doctor. There are some red flags, however, that may require you to seek additional medical attention right away. These include:
- sudden new migraine symptoms, like an aura
- changes in the type or frequency of migraine attacks
- new vision or neurological changes that accompany the aura or migraine attack
- sudden intense pain in one area (thunderclap headache) that could signal bleeding in the brain
- headaches that come with speech or balance impairment, facial drooping, or other possible signs of stroke
There’s still a lot that’s unknown when it comes to migraine with aura and electrical activity in the brain. There are some medications that may help achieve better balance in the brain, but it’s not clear yet whether these can also translate to a reduction in migraine with aura.
If you suddenly experience new types of migraine attack or a sudden uptick in attacks with aura, you should schedule a visit with a doctor.