Um... My 18 year old brother talks to himself. He's been doing it for a long time. I can't remember for how long but I think he didn't do it when he was a young child.

I know he has some depression once in a while if something upsets him but he recovers quickly. He almost never goes out and I doubt he has any friends. The only times he goes out (socially) is with my older brother and my brother's friends. He is socially awkward but that's not why he doesn't have friends. The reason why is because he just doesn't make any, almost like he's too lazy to do it or something. I can't describe it.

But anyways, my concern is that he talks to himself. He'll ask himself questions and answer them. He'll comment on shows out loud and not just exclaiming something, he debates something in what he's seen with himself. It's not your occasional "what the heck" or "why did I do that?!"

we tell him to be quiet if we're watching a movie so he knows he's doing it to a point. Sometimes he gets defensive if you confront him and ask why he's doing it or if you say, "stop talking to yourself."

it's like he has no inner monologue.

Is there anything that can be done? Anybody know why he does this?