I have these once in a while (no pain, just annoying) and I am pretty certain that for me dazzling pinpoint light triggers them. I am interested also.
I have a good number of triggers, but things like flickering fluorescent lights are a sure fire trigger every time.
I get them pretty bad where I can’t see and will puke if I don’t get my meds in time (I usually have to take them at the first sign of an aura or I am down all day).