I was a little surprised when I entered "tetris syndrome" into the search engine and it actually gave me results. Apparently I'm not the only one who couldn't get the "floating Tetris pieces" out of my head back in those days.
Similarly, when I took art lessons, we often talked about composition and shapes. We were taught to "see." I remember the teachers paroling the classroom, often commenting, "You need to draw what you see, not what you THINK you see." And I would leave the classroom and walk across the campus, seeing not trees and people, but triangles and squares and areas of dark and light.
But what reminded me of this concept wasn't computer games or works of art. It was the topic of problem-solving and how we get used to thinking in a certain way.
I lay awake in bed last night planning an ESL lesson, even though I probably won't be teaching for another month. The wheels started turning and before I knew it I was visualizing handouts and role-playing and having imaginary conversations with my students (I keep a notepad by my bed for such moments). If you're in a profession where you constantly need to plan and come up with ideas, your brainstorming skills might be "triggered" easily.
What you apply your mind to will often stick with you, whether it's a visual occupation or not.
I wonder what people in other professions dream of.