Tell me about migraine auras. Please?

I hope there isn't already a thread on this, I double-checked. Not entirely sure if this thread is in the right place either, apologies...

So, I know a little bit about them, but I keep finding the same information everywhere I turn. My main question is what causes them, and the information I've found so far seems universally ambiguous in terms of answering that question.

I'm relatively new in researching this, so any information or directions on good places to look for it would be quite helpful.

Also, if anyone experiences this themselves, a description of your particular symptoms would benefit me tremendously.

I get a rainbow coloured, shiny, spinning double helix-like moonshaped structure on the left or right side of the visual field. It changes shape and can migrate around. Usually it floats outside of my visual field in 30 - 40 min.

The way I understand it the reason isn't known yet. There are various hypothesis. One I think I read about the blood vessles pressing against the nurons, thus resulting in these reactions. But I didn't really study it, so I don't know for sure.

Hmm. That makes sense. Sort of like the images you get when you close your eyes and external pressure is applied; just internal pressure instead?

Your visuals sound totally different from mine, but I shouldn't be surprised at the variation. Mine stays in one spot, and grows outward [even though is seems to be spinning inward simultaneously].

The closest simulation I've found to what I see is this:

I'm a migraine sufferer. My auras look similar to the effect that you get from staring at a bright light for a while, only a bit more transparent and covering ~80% of one side of my vision. They start on the left side, then shift to the right, then disappear. After the aura disappears, the pain starts on the left side and feels like an elephant is crushing that side of my head. The only cure at that point is sleep. :sleepmeditate2:

A friend of mine gets something similar, but they're darker and start from the edges and slowly block all of his vision.

The closest pic's to my experience I could find on the net... some of the first ones you get if you search for migraine auras in google.
http://t2.gstatic.com/images?q=tbn:m...ges/aura14.jpghttp://t2.gstatic.com/images?q=tbn:l...vRVqCM:http://

I must say though, I've never really felt the pain at least not an "elephant crusing my head" kind. A headache which is most often mild. But mostly just nausea, being tired and "zoned out".

I've heard that there are those that experience auras, but don't experience the migraine that follows for others.

Mine is sort of in between; sometimes I get one, sometimes not.

Luckily I haven't had one in a while now.

:knock on wood: