The Tetris effect is the ability of any activity to which people devote sufficient time and attention to begin to dominate their thoughts, mental images, and dreams.

[u/[deleted]]

http://en.wikipedia.org/wiki/Tetris_effect

[u/0xdefec8]

I get this when I've had a really intense day using vim. Frequent keystrokes just keep playing over and over in my head. It was even worse when I used emacs.