I've had that sort of thing on and off for about 30 years, mostly off. It was diagnosed several times as "ophthalamic migraine." It's like having the warning aura of a migraine without actually getting the painful headache part. Sometimes I feel nausea or intestinal discomfort, but usually not. I don't take medication for it. But I have had times when I had it almost all the time for a year or more. That was before I figured out the triggers.

It always gets worse with fluctuations in female hormones and if I eat too much of the foods that are known as migraine triggers -- when I gave up chocolate (), grape juice and aged cheese it dramatically improved. Oh, and nitrate and nitrate food preservatives! Those are the worst. Which I forget this time of year because many Xmas goodies are made with dried fruit, like dates, which usually contain it. Salami, lunch meat, hot dogs, Hickory Farms Sausages and treats. All full of nitrates and nitrites. The holidays are a terrible time for migraine triggers.

I've also run to the eye doctor thinking I was having a detached retina, but my eyes have been okay.

The topamax drug Hankster takes is often prescribed for migraines. On a more serious note, seeing flashing and flickering lights can be a warning aura for seizures. Topamax is prescribed for seizures, too.

Here's some WebMD info on migraine triggers. If I avoid the food triggers, I usually don't have symptoms. If I eat one date or a piece of dried pineapple or a single slice of salami, the lights will flicker for 3 days.

Frequently Asked Questions About Food Triggers, Migraines, and Headaches