I have been sleeping with a light on for many years, and had gotten a
loft bed last year and was still sleeping with the main room light on, which is 4 light bulbs on my ceiling fan, in February, I had started seeing like an after image of my veins, it was the same image, and had been improving. but would appear if i strained my neck. but i am reading that neck strains cannot really affect optic nerves.