I'd say welcome to JU, but your profile says you've been here awhile...so welcome back?
I'm currently working toward a Master's Degree (yeah I know people are getting sick of hearing it, but certain situations call for prefacing it with that comment. This is one.)
I am one of those talk out loud people in class. In fact I got two fairly dirty looks from some classmates yesterday for this trait.
They can kiss my butt. I am paying for these classes, and they ain't cheap. I intend to suck every bit of information from my instructor's cranium as possible. I do that by asking questions or by interacting. That is how I learn.
So, perhaps this is the way your "loud mouth" learns as well? I usually wait about three seconds for someone to answer a question I know the answer too, just so I'm not answering all the time. But I still answer over half the questions in the class. The others just sit there, like they haven't done the reading, or they want to just get it over with.
My instructor thanks me after every class for participation. She told us at the beginning it was ten percent of our grade. She said there were going to be some mighty unhappy people at the end of the quarter because she really sticks to it.
Well, anyway, heh, just giving you the loud mouth perspective. 
