(LifeWire) - For a small group of migraine sufferers, the discomfort associated with migraines is not just in their heads. Approximately 15 to 20% of migraine sufferers also experience migraine aura, a brain dysfunction that can result in strange sensations all over the body. Auras are generally viewed as a warning that a migraine is coming.
Auras can occur 5 to 60 minutes before the actual onset of the headache. The aura usually lasts 10 to 25 minutes but, in rare cases, it may continue for the duration of the headache. Occasionally, auras will occur without a subsequent headache. Individuals who experience aura without headache should see a doctor to rule out other medical issues.
Experiencing an Aura
Migraine auras can affect sight, hearing and feeling.
The visual disturbances of an aura can include sparks or flashes of light, called "phosphenes," and a dark spot or area of diminished vision, known as a scotoma, that moves through the visual field. Visual disturbances that include dark spots with flickering edges are called "scintillating scotomas." Auras may also involve visual distortions or changes in the shape of objects.
In extreme cases, auras can appear with elaborate hallucinations. This is sometimes referred to as "Alice in Wonderland Syndrome," which derives its name from speculation that the Alice in Wonderland story was inspired by the migraines experienced by the author, Lewis Carroll. These extreme disruptions can include seeing distorted or flying objects, or a spiraling "black hole" in the visual field. A small percentage of sufferers report seeing odd changes in the faces of other individuals, such as moving eyes or stretched features.
Temporary deafness, auditory hallucinations (hearing voices), or ringing in the ears are also forms of aura.
Auras can also include tactile disruptions, as some sufferers describe feelings of heaviness, numbness or pins and needles sensations in their limbs. In extreme cases, sufferers report floating sensations, or feeling as though their body mass has doubled.
Rarely, speech disturbances, such as slurring or stuttering, can also occur. Individuals who experience these types of disturbances for the first time should see a doctor, as these symptoms may also be signs of stroke.
Distinguishing Between Retinal Migraines and Migraines with Aura
Due to similarities in their symptoms, one-eye, or retinal, migraines can be difficult to distinguish from migraines with aura.
Retinal migraines can also result in blind spots or shades of gray in the visual field. However, retinal migraines exhibit one key difference: only one eye is affected. Individuals experiencing a migraine with aura develop visual disturbances in both eyes. The visual disruptions resulting from retinal migraines are caused by increased pressure on the blood vessels leading to and from the retina. Thus, if an individual experiencing a retinal migraine closes the affected eye, the symptoms should stop. Individuals who experience retinal migraines should consult an ophthalmologist or neurologist to rule out other conditions, such as stroke.
Causes and Triggers of Auras
Though the exact cause of auras is unclear, research suggests that as chemical impulses move through the visual processing center of the brain, the disruptions or hallucinations appear. Brain scans taken shortly after the onset of an aura showed increased activity in the occipital cortex, the technical term for the visual center of the brain.
Because auras are almost always associated with migraines, the migraine triggers may also be responsible for auras. These triggers typically include stress, fatigue or exposure to bright lights or unusual smells.
As women are more likely than men to experience frequent migraine auras, hormonal changes also seem to be a trigger. Approximately 60% of women report experiencing more intense or more frequent migraines during their menses. Women with a history of migraines should mention this condition to their doctor before taking hormones, either for birth control or menopause symptoms. Research suggests a correlation between use of these medications and migraine frequency.
According to a recent study, women who experience migraines with aura have a 1.5 times greater risk of having a stroke than those who have migraines without aura. In women who smoke or use birth control, the risk of having a stroke increased to 7 times greater than those who experience migraine without aura.
Another study also found a relationship between migraines with aura and brain lesions, which have been shown to increase the risk of having a stroke and developing cognitive problems, including dementia. According to the study, individuals who experienced one or more migraines with aura each month had the highest risk of having a stroke.
Treatment for Migraines with Aura
At this time, there is no specific treatment for auras. Instead, most physicians treat the migraine symptoms. Medications can range from over-the-counter, anti-inflammatory drugs, such as ibuprofen, to prescription-strength pain relievers. Keeping a migraine diary, reducing stress, and regular exercise may help limit the occurrence and intensity of migraines with aura.
Individuals who experience migraines with aura should see a doctor to rule out any other conditions, such as stroke or a detached retina.
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