What happens is that you in fact lend part of your brain to all the data that you see on your screen. You don't realize it but your subconscious mind sees senses a lot of stuff your conscious mind is not aware about. Until you see it after you just talked about it thinking it was your idea and panic.

What you actually talk about with people (excluding maybe the proffesional stuff) is mundane stuff you see on your screens, newspapers, billboards, etc.