What's a giggle loop?

Jeff: Don't ask! To know about the Giggle Loop is to become part OF the Giggle Loop!

Steve: I think we can take it.

Jeff: You're not ready for the Giggle Loop.
...
Jeff: Basically, it's like a feedback loop. You're somewhere quiet. There's people. It's a...solemn occasion. A wedding. No--it's a minute's silence for someone who's died.

Steve: Right.

Patrick: Okay.

Jeff: Right, minute’s silence ticking away. (Makes ticking noises with his tongue) The Giggle Loop begins. Suddenly, out of nowhere, this thought comes into your head. The worst thing I could possibly do during a minute’s silence is laugh. (Overturns a beer glass) And as soon as you think that, you almost do laugh, automatic reaction. But you don’t, you control yourself. You’re fine. Whoo… But then you think how terrible it would have been if you’d laughed out loud in the middle of a minute’s silence. And so you nearly do it again, but this time it’s a bigger laugh. (Stacks another beer glass on top of the first one) And then you think how awful this bigger laugh would have been. And so you nearly laugh again, only this time it’s a very big laugh. (Stacks another glass) It’s an enormous laugh! Let this bastard out, and you get whiplash! (Stacks another glass) Suddenly, you’re in the middle of this completely silent room (stacks another glass) and your shoulders are going like you’re drilling the road! And what do you think of this situation? Oh, dear Christ, you think it’s funny!