Laughter

00:00:00,080Of all, I'll start by looking at the actual nature of laughter. Well, when someone laughs, you've got movement of the muscles of the face and the chest, and you've got sound formed when the air is forced out of the body as part of this process. So we're talking about a physical activity, but obviously other things are involved as well, and this is where it gets more complicated. Laughing isn't something that you normally decide to do, so it's not voluntary behavior like ordinary spee...