Wednesday, September 3, 2008

What's Your Aura, Dude?

Fascinating article on recent research on migraine headaches in the August issue of Scientific American. The majority opinion no longer relates migraines directly with vascular or blood issues, but with cortical storms related to either the visual cortex, the brain stem, or both. In the article, the authors described the auras experienced by many migraine sufferers before an attack. While some are simple flashing lights, many are highly organized patterns of bright points, followed by a negative-image pattern of dark points. There is speculation that the sufferer might be seeing his/her own visual cortex firing pattern, or another internal neural network.

Eureka! Ever since I was a child, I've seen such moire patterns in dark rooms, and can bring them into my visual field at other times as well. They alternate as trapezoidal, hexagonal, or octagonal patterns of light firing. I thought everyone experienced it. I've never had migraine or epileptic symptoms, however. I visited a fascinating migraine aura web site maintained by German researchers, and realized there is a significant minority of people who experience moire-pattern auras without migraines. I don't have these experiences often as an adult, but if I concentrate, I can "will" the pattern to overlay my normal vision, like a scaffolding over the visual field. Says something interesting about visual perception and cortical storms, I guess. Do you see this? What's your aura?

7 comments:

Sharon said...

Hey Dude,
no aura here...at least not visually. But I am color blind and often wonder what kind of artistic and fashion faux pas I make due to my muted perceptions. Like the time I came home after spending $200 on new glasses (my birthday present that year) and found that the frames were rose pink! UGH.....I'm really not a pink kind of gal (I thought they were black). Visual perception is pretty amazing.

My spiritual aura on the other hand I would love to see!

Loring Wirbel said...

If you can't perceive pink, how do you know you'd find pink yucky? Now there's a question.

Sharon said...

It all depends on the lighting.....as is true of most everything. :)

Ruth said...

Ha, that's a good question, Loring. To Sharon I mean.

Nope, no auras for me either. Glad you don't have migraines.

Brian Santo said...

Fascinating. I do not get migraines, but when I was a very small child I discovered that if I closed my eyes and pressed gently on my eyelids, I would see these amazing, changing moire patterns. I still can.

I've always perceived the patterns as black and green.

Loring Wirbel said...

OK, another one! Mine turn green too, same basic moire. Definitely something with visual cortex connections to eye, methinks, particularly with pressing on the eyelid. I wonder if this is a genetic-marker thing like curling your tongue or hating broccoli?

jess said...

i thought i was a freak for pushing on my eyeballs all this time. and if you close your eyes and look inside you can see the red veins. it helps if there's a little bit of light.