Experiment.
Look away from your screen on a random point and scan your eyes from one side to another. Can you do it smoothly?
My eyes jump in steps. Even when I try to “scan” is actually just steps across the span. The only way I can do a smooth look if I am looking at something and following it.
My eyes aren’t stepping, the are smooth but I actually see steps - They are looking and scanning but my brain only processes in steps?
Chat.
Yeah, your brain filters out a lot of the movement.
It’s why you don’t feel sick when looking from side to side, but you might do if filmed footage of the same movement was shown to you.
I remember reading something about this years ago with a scientist attributing this to why people occasionally don’t see motorbikes if they just have a glance when pulling out of a junction (his logic being that a larger vehicle is less likely to be ‘masked’).