Migraine with aura is said to be experienced by 1 in 5 migraineurs, or in 20 - 30% of people. For some time now medical professionals have believed aura to be caused due to blood vessels in the brain constricting. However, more recent explanations point to the hyperexcitability of brain cells causing changes to the brain’s chemistry, which in turn affects peoples’ ordinary senses and perceptions.
Aura is a fully reversible neurological syndrome which can develop over 5 minutes and typically lasts upto 60 minutes, if it occurs longer than this it is termed ‘prolonged aura’. In rare situations, certain individuals can experience aura lasting days, weeks or even months. It tends to occur before the onset of a headache, with a headache usually developing within an hour after the aura has disappeared, but it may develop a lot sooner or the aura and headache may be present at the same time. Migraineurs who experience auras tend to report them very differently, some find that in certain circumstances the headache precedes the aura, whilst for others they experience the headache alongside the aura. Reports indicate that sometimes migraineurs will experience only the aura and no headache will follow. However, it seems true that most people who have migraine with aura, also have episodes of migraine without aura.
Having a headache or aura symptoms are not normally the first sign of an impending migraine attack; some migraineurs start to feel “strange” a day or so before the attack begins. These strange feelings, known as the prodrome, are the first signs of the attack and can include:
|Cravings for certain foods,
||A change of mood
Forms of aura
Visual aura occurs without warning, a blind spot may appear in a similar location in both eyes. For example, blind spots which increase in size, or a zig-zagging or sparkling margin. It may be accompanied by apparent flashing lights, by geometric shapes, or by unusual forms. Some migraineurs may experience unusual perceptions or hallucinations and a very rare form of aura known as “Alice in Wonderland” syndrome. This syndrome is identified by the perceptions of the sufferer; their body or other peoples’ bodies look distorted, so that things appear larger or smaller than usual, or further or closer away (“macropsia / micropsia”).
Sensory aura is when a person experiences changes to their sense of touch, they may experience a sensation of “pins and needles” which move up and across the face, neck, upper back, arms or legs. This tingling sensation is usually followed by a sensation of numbness which can last for up to an hour. Some people may also experience hypersensitivity, or pain in reaction to mild stimuli (“allodynia”) particularly on the scalp or forehead; however, allodynia forms part of a migraine attack and is not classed as an aura manifestation.
Difficulty with speech and language can also be the symptoms of an aura; a person may have difficulty thinking logically, finding words and / or making sentences and slurring speech.
Other types of aura can include an odd smell, mental confusion, and individuals may experience other odd / unusual sensations including fainting. Any one of the above auras can develop individually or they can occur simultaneously.