Silence...

So I was taking a stupid on-line quiz the other day and one of the questions asked, "How long has it been since you've spoken out loud?" I started thinking about it and realize I go hours, occasionally even a couple of days without really saying anything out loud. I mean I'm thinking most of the time and sometimes, it seems like I've been talking to someone, but.... I'm pretty sure the words never actually formed in my mouth. This doesn't bother me, I don't usually feel excessively lonely or isolated, but then I wonder, is it really OK to spend that much time alone in my own head? I used to do it to the point of insanity, I've relaxed a lot, but I find myself mostly content with the silence...