Reminds me of the well known "Tetris effect" where you see falling blocks long after you stop playing the game. I have experienced both sensations, but have neither shot nor dropped bricks on anyone.
Interesting. I figured it was something like that, since the images didn't match any though patterns I was having.
Same thing happens with falling arrows and DDR
True story: I got DDR not long before the second time I took the SAT. The night before the test, I played until around 4 AM. On test day, this is what I saw every time I blinked: http://i.imgur.com/hTk7Q.png
I'm a heavy player, and unfortunately I've never had the joy of seeing arrows flying around me during the day.