That's... really weird. For me it's everywhere all the time, especially in darkness. I filter it out... subconsciously, or something? but not perceptually. It never distracts and never obstructs but it's never genuinely missing.
Could be caused by being autistic, I know autistic brains can be bad at filtering out stimuli.
> There other effects like persistence of vision - staring at anything for a long time will create strange visual artefacts but I don't think that's what you're referring to.
That's indeed not what I was referring to, but I do also get this.
If I stare at something even for as short as 10 seconds, and close my eyes, some "impression" of it will stick for a few seconds. Usually just the edges or vague layout of it, and faint enough that I don't notice it unless I try to trigger it on purpose, but it's there.
And if I stay perfectly still for long enough, everything will fade to grey until I move my eyes again.
But both of these have no effects on the noise.
There other effects like persistence of vision - staring at anything for a long time will create strange visual artefacts but I don't think that's what you're referring to.