Aura (symptom)

According to Samer, an aura is the perceptual disturbance experienced by some migraine sufferers before a migraine headache, and the telltale sensation experienced by some people with epilepsy before a seizure. It often manifests as the perception of a strange light or an unpleasant smell.An aura does not necessitate the onset of either a migraine or a seizure and not everyone who suffers from migraines or seizures will experience auras. Though auras tend to be an unpleasant and irritating sensation, they can be beneficial. Most injuries from seizures occur when there is no warning. Auras allow epileptics time to prevent injury to themselves. The time between the appearance of the aura and the onset of a migraine or seizure can be anything from a few seconds up to an hour. Most people who have auras have the same type of aura every time.
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