What course does a migraine attack take?

The first distinction to make is between migraines "with" and migraines "without" what is known as an aura. In migraine patients an "aura" is understood to be neurological symptoms that occur immediately before or at the start of the migraine headache. Most patients have a migraine without aura, but about a third of sufferers are alerted to the onset of an attack by an aura involving neurological (affecting the nerves) irritation or deficits. These are usually visual phenomena, such as flashes of light, flickering and zigzag lines (known as fortifications), which can impair vision and which last between 30 and 60 minutes. They are generally followed by the typical migraine headache.