I sometimes get shimmering patterns which I think they call visual migraine or https://en.wikipedia.org/wiki/Scintillating_scotoma but thankfully mine don't go on to migraine proper. They often seem set of by a bright light outside the center of vision like I'm reading a book with sunlight coming in from 45 degrees.

Exactly the same trigger here. I had one just the other day at the pub. Sitting outside, under shade, but to my left was a bright spot. It’s weird how I can sense it arriving ... something about the quality of my vision subtly changes, and there it is.

Fortunately for me it isn’t accompanied by a headache. It’s just really unsettling. At least now I’ve learned to recognise them and I just try to chill out while it does its thing.

(FWIW, also a tremendous consumer of caffeine here. But this was at 17:00, a good 5 hours after my last cup.)

For whatever it’s worth, too much caffeine and dehydration does this to me. Chugging about 48 oz of water and throwing on a face mask for 30-60 minutes usually clears it up. If I do “nothing” it takes significantly longer to clear up.

I get the same, and all of these tend to be a trigger for me too -- too much caffeine, dehydration, and rapid light intensity change (like looking outside and then back to my computer screen).

In addition to chugging water and staying in the dark with a face mask, I've found that taking raw honey right as it's coming on makes it go away rapidly.

My long term prevention is taking magnesium daily and LSD once or so a year. Once I started doing that the frequency went to almost zero, and whenever I don't do that they start up again.

In my case it's the combination of too much caffeine, dehydration, and intense exercise where my HR maxes out. 2/3 risk factors will typically not be enough to trigger one for me. HIIT workouts and soccer have done it in the past.

The aura (with scintillating scotoma) starts coming on usually an hour or so after the exercise is done, and I know I've got about 15-20 minutes before the actual migraine hits. Got prescribed Sumatriptan and it maybe reduced the intensity by about 25%. I'll have to try the water chugging, maybe with rehydration salts to speed up absorption.

I've had fewer than a dozen episodes starting last year. Luckily, like you, I have scintillating scotoma without headache. I haven't noticed a trigger--they're just spontaneous. A couple of years before, I had a couple of episodes of binocular diplopia (https://www.yalemedicine.org/conditions/double-vision). Dunno if they're related.

I've mentioned this before in previous HN threads about scintillating scotomas, but it's worth repeating: in my case, the issue was entirely due to excessive caffeine consumption. When I got them frequently I was sometimes consuming upwards of 450mg/day, when I cut intake way down they disappeared entirely, and when I occasionally fall off the wagon and have way too much that's when they come back.

I've been getting scintillating scotoma for over 50 years. They've changed character over the years from widespread fortifications to virtually no scintillation at all but always progress from a bright spot to a large blind spot to an expanding toroidal blind region with vision restored at the origin point until they pass out of my field of vision. They used to lead to headaches and sometimes speech deficits or other somatic experiences (like sizzling on my tongue and lips) but now I just get mild abdominal discomfort. With a couple of notable exceptions it lasts about an hour.

I have learned that while they're inconvenient, they're harmless and I just generally continue with whatever I was doing when they began. I have never been able to discern a trigger: they appear to come on completely randomly.

Exact same story here, including the occasional speech problem. Well, I've only been getting them for 30 years. It's always reassuring to hear this from people who have been getting them for longer than me. They used to freak me out when I was younger. Still worry me a bit when I get multiple in a single week.

I used to get these two or three times a year, but then I had heart surgery last summer and had five in the first day after I came round from the anesthetic, and two or three every day for weeks after that. They've now settled down to one every few days. Annoying, but they go away fairly quickly and just leave me feeling a bit tired and headachy for a few hours.

Same story for me, had a minor ablation procedure which triggered a bunch of migraines that later settled down.

Yep, I realized mine were caused by looking out the window while I brushed my teeth in the morning. One day it was really bright outside and really dark inside and the migraine started almost immediately. More than a year and I keep the blinds drawn while I'm in the bathroom in the morning and not a single migraine!

This is interesting. I frequently had them triggered by riding BART in the late afternoons in the winter, sun beating in through the dirty windows. Going through the tube (dark) and emerging in Oakland (raised track, clear view of the sky on both sides) had a double-digit % chance of giving me a migraine if my eyes were open at one point.

I can get them triggered by riding in a car in similar conditions, too, especially if the windows aren't squeaky clean. I frequently wonder why that is, something about the remaining spectrum of visible light when the windows are dirty?

Reminds me of wearing non-prescription sunglasses despite having myopia. It feels like the blurring of the world is due to the glasses, even though they're actually only blocking some of the light rather than distorting it.

That feels pretty similar to my story. I always put it down to some kind of puberty changes.

Yes! At least some migraines are caused by whatever second-order effect there is from hormonal changes.

I'm glad you shared this - I also have light triggered migraines and I didn't realize there were so many others who also did. :) huh! I take ibuprofen and two shots of espresso and lock myself in a dark room and do deep breathing/relaxation -- the latter seems to have been surprisingly helpful for me in the last few years, and makes me wonder if my anxiety response to having the initial aura was actually contributing to worsening the migraine.

My favorite episode was when I went to my doctor, said "yeah, it's good, I haven't had a migraine for like 6 months", and as part of the physical he shined a pen light in my eyes ... and I went home and developed a migraine. sigh.

(Fortunately, some time in my 20s, I stopped getting the headache part for the most part and now just have aura -- which renders me partly unable to see, alas -- and feeling pretty off for a while.)

Have you tried cold brew? It has about 10x the caffeine of an espresso shot. Espresso has the least amount of a caffeine of coffee drinks. Cold water and long exposure extracts more caffeine than hot water and short exposure. Source: I’m a coffee nerd.

The difference isn't typically that vast. At usual dilution levels, drinking a 16oz cold brew would be slight caffeine gain on the double-shot. Heat does extract caffeine better that cold, which is why the shot is prepared in ≈25 seconds and the cold brew concentrate takes 12-20 hours.

Source:10 years experience as a working barista.

Also, I don't keep cold brew on hand during the winter, but I can whip up a double espresso in under a minute and get ~150mg of caffeine, which is basically equal to my daily intake. And I can _consume_ it faster than trying to chug a 16oz cup of cold brew. Gulp, done. :) And yummy.

I could take the excedrin-style things but coffee is pretty easy. And the goal isn't "max caffeine", the goal is 150-250mg.

The funny thing is that I really have no idea if this caffeine+ibuprofen routine is actually effective. One of my doctors in grad school suggested it, as someone who also suffered aura-only migraines. He said it worked for him, and I figured that either it was sometimes effective, or I'd have some placebo action working for me, so I just adopted it. :) I'm OK with placebo if it's working. The caffeine is based on an older theory of vasoconstriction that seems to not be aligned with the modern thinking on migraines, but, eh, mine are pretty tame compared to what some people get so I haven't felt the need to work too hard to optimize this.

There are OTC meds you can buy that are marketed as "migraine relief" that are just acetaminophen + caffeine; my wife takes that and it usually works to relieve the symptoms (if she can catch it early enough).

Of course, then you take away the espresso - there's always a trade-off :)

Same! My understanding of migraines is that it's something to do with blood pressure in your head. My hypothesis is that the visual disturbances are your blood vessels dilating and pressing against your retina. Then I think it can cause kind of a runaway feedback loop of some sort that causes the blood pressure to increase throughout your head, causing pain.

Thinking about it now, I wonder if the light trigger could be the bright light causing minor damage to your retina, potentially triggering an inflammation/repair response. The fact that it happens when going from dark to light suddenly, also makes sense, since your pupil is at its most dilated when in the dark, meaning the most of your retina is exposed/vulnerable. That might also explain why it always starts in the periphery; because the edges of your retina are likely less often exposed to light and potentially more delicate -- but would be exposed if you see bright lights while your pupils are fully dilated.

For me, I've found it's also closely related to irregular food or sleep. And I find eating something with sugar or drinking some water can reduce the likelihood of the visual disturbances becoming a full-on migraine. My hypothesis is that these things alter your blood chemistry/physics enough to interfere with the runaway feedback loop that results in increasing blood pressure. I imagine dunking your head in cold water likewise works because it breaks the runaway process.

But this is all speculation.

Just for what it's worth, the middle third of the article is about the proposed limbic system causes of migraine.

I also discovered the dive / ice water reflex sometimes helped my migraine. The reason I tested it is because caffeine supposedly releases some chemicals related to the same chemicals that are released when you vomit. Since my migraines always ceased after vomiting, I used these other methods to induce the same chemical response in the brain.

I now keep Excedrin migraine on hand (has caffeine). However, my migraines completely ceased after I stopped using nasal steroid spray and started with an allergy nasal spray.

I underwent allergy treatment that stopped working, so I decided to try steroid medication. After about four days, I began experiencing unusual migraines every day. I had migraines before, but they always came with a headache. However, with the steroids, I started getting just very strange optic auras. Everything began to sparkle out of nowhere, becoming more intense until I had to close my eyes. The symptoms stopped once I discontinued the steroid treatment.