Lines of oooooo are lines, not groups and they are not close enough together to provoke a reaction.
Abbie some scientists reckon it's related to decay or disease/parasites. Rotting wood for example would definitely set it off, as does woodworm. So it could be a primal instinct to warn us away from danger. DH read an article that says 20% of women have it and 10% of men.
It was my thread, BTW, and there are no pictures on it (any more? I think someone posted one which was deleted)
I don't find it a problem TBH. I hardly ever come across things which trigger it naturally, not seriously anyway, maybe a little bit (but even that is fairly rare).
Those book sculptures popular on social media about a year ago set me off.