Migraine auras - the additional disturbances that can accompany the pain (or, in some cases be present without the pain) [0].

[0] https://my.clevelandclinic.org/health/diseases/22131-migrain...

Visual disturbance.

I get a blind spot near the center of my vision that looks a bit like what you see when you rub your closed eyes. It gets large enough to mostly obscure faces and prevent reading