Determine in brief about the Classic migraine

This is probably the most interesting form, occurring in about 12% of migraine sufferers, because it begins with an aura, which usually lasts for 20 to 40 minutes. The aura is thought to occur because constriction of one or more cerebral arteries has produced ischemia of the occipital cortex.

The results of PET studies have shown that, during the aura, there is a reduction in blood flow in the posterior cortex, and this reduction spreads at the rate of about 2 millimeters per minute, without regard to its location