How do we control our eyes to not focus on distractions?
It may be difficult to imagine, but what we see "out there" is not a passive input of data onto some sort of neural screen in our brain. Rather, what we see is our "projection" onto the world out there of a model we have learned for interpreting that visual data.
So, it is the brain that sees. The eyes are just one set of receptors (albeit a highly important one) through which we make sense of the world. Our brain attends to whatever we need, fear, or are interested in, sometimes to a degree that seems impossible.
Go look on YouTube for one of the many videos on "the invisible gorilla" experiment on selective attention. Even with knowing what is about to happen, many people cannot see something right in front of their eyes!
_Written by J. Trevor Woodhams, M.D. - Chief of Surgery, Woodhams Eye Clinic