Yes unfortunately i do this all the time and always have done. I have mentioned it in another thread. I have full conversations with myself but the thing is i know i am not talking to myself. I have someone in my head that i am talking to, it could be anyone, a friend or even someone that i have never met. Sometimes it's just a conversation but other times it can be an argument and i might raise my voice but not in an overly aggressive way. Sometimes i repeat the same conversation over and over but with different responses. I honestly don't know why i do it. I know i'm not talking to anyone really but the conversations can be really long and involved sometimes. It's not an occasional thing either, i do it all the time. I got a reputation for doing it at one of my work places, everyone used to think it was funny but i'd find it embarrassing when i got caught by someone.