Ask if anyone in a group gets migraines, and the nodding faces will no doubt have a haunted look to them. These strange and often debilitating headaches come with a host of unpleasant symptoms, one of which is psychedelic patterns in the affected person’s vision. So, what are they?

The strange patterns people see when they’re experiencing a migraine are known as migraine aura. They don’t affect everyone who gets migraines, and they can look very different, but they typically present as jagged zigzag lines, circles, flickering lights, static, or blind spots, often in scintillating and psychedelic colorways.

As a headache disorder, migraines are among the most common, affecting around 12 percent of the population. There remain many unanswered questions as to what exactly is happening during a migraine, but it’s believed to be the result of neuronal dysfunction setting off a chain of events in the brain.

“Around 15 percent to one-third of migraineurs experience aura,” explained Dr Christian Lucas in the journal Revue Neurologique. “Aura is a fully reversible focal neurological phenomenon involving visual, sensory, speech, and/or motor symptoms that develops gradually and usually precedes the headache phase.”

“Visual aura is the most common type of aura […] It often presents as a fortification spectrum: a zigzag figure near the point of fixation that may gradually spread right or left and assume a laterally convex shape with an angulated scintillating edge, leaving absolute or variable degrees of relative [blind spot] in its wake.”

Lucas reports that there’s a large body of evidence pointing to cortical spreading depression (CSD) as a possible driver of migraine aura. This phenomenon is characterized by a wave of depolarization that sweeps across a part of the brain called the cerebral cortex.

It can alter the way blood flows, causing a range of neurological conditions and symptoms, including migraine aura. As the developing CSD changes the flow of blood to parts of the brain and triggers the release of neurotransmitters, it can activate different sensory pathways, giving rise to different sensations. Visual disturbances like migraine aura are likely due to the activation of visual pathways caused by the CSD.

Migraine aura in itself isn’t dangerous, but there’s a risk of it being misdiagnosed in more serious cases where the visual disturbances are caused due to something like a transient ischemic attack (TIA), also known as a “mini-stroke”. 

Migraine aura is also associated with an increased risk of stroke, especially in people taking certain types of hormonal birth control. For that reason, people who experience migraine with aura should inform their healthcare provider in case it’s relevant to drug prescriptions or future medical decisions.

The one perk of migraine aura is that while the visual symptoms can’t be stopped, it can provide a window of time in which a person can take steps to prevent or lessen the severity of the looming migraine. As warning lights go, at least a scintillating zigzagged rainbow is original.

The content of this article is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of qualified health providers with questions you may have regarding medical conditions.   

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