Migraine is a neurological disorder that causes recurring headaches ranging from moderate to high intensity. Typically it effects only one half of the head and can last from 2 hours to up to more than 2 days. When under a migraine attack, the sufferer may become extremely sensitive towards light or noise. Other common symptoms include vomiting, nausea and pain aggravation due to physical activity.
from Yoga Buzz http://www.artofliving.org/yoga/health-and-wellness/yoga-for-migraine