One source of visual noise is clutter. I'm "noise sensitive" in the audio sense. When my environment gets too loud, I get agitated and feel a desperate need to escape. I can see how visual "noise" can also contribute to feeling overwhelmed.

This is one reason I have so many sub-folders in my Windows Explorer and in my email. I have seven different emails to keep my activities separate. But in each one, I keep my inbox as close to empty as possible. I file each email to a sub-folder until I'm ready to read it.

I'm not as good at minimizing visual noise in my apartment!