A Migraine attack can consist of up to four phases:
• Prodrome Phase
• Aura Phase
• Headache Phase
• Posdrome Phase
You can find the phases and their potential systems described in our article Anatomy of a Migraine.
Not all Migraineurs experience all of the phases, and one Migraine attack can differ from another. One of the many myths and misconceptions about Migraine disease is that all Migraine attacks include the aura phase, and that if there's no aura, it's not a Migraine.
In reality, only about 25% of Migraineurs experience the aura phase. Many people also think that auras are always visual. This is also incorrect. Migraine aura can also be auditory (hearing), olfactory (smell), or include tingling and / or numbness.
Here's an excellent video about Migraine aura featuring Dr. Stephen Silberstein of the Jefferson Headache Center: