seeing things

When I get a migraine, I usually know it's coming because I get an aura. The aura normally starts as a little bit of static, like on an old black-and-white TV, in the center of my vision, and becomes a doughnut which gets bigger and bigger until it disappears at the edges of my vision -- and only then does the headache actually start to hurt. I've found that if I take Excedrin right when I notice the aura, I can sometimes preempt the pain altogether.

Last night an aura started just as I was getting ready to go to sleep, and I took Excedrin and turned out the light. Then I noticed the aura looked different. It had colors in it -- I noticed the robin's-egg blue and the orange first -- and stripes, and pointy things. It was so pretty, I tried to describe it to majordomo, but had to settle for watching it grow and trying to remember so I could draw it when I woke up this morning. I think I made a pretty accurate representation:

From aura

What you can't see in this drawing is the strobe effect. Imagine, if you can, that everywhere that's black in the drawing becomes white and everything that's white becomes black, and then it reverts to it original state, and back and forth like that almost-but-not-quite fast enough to appear gray. Makes me wonder if the aura *causes* the headache.