Well, my guinea pig died 2 months ago, but while I had her, I was also in a psychology class. So, she was very literally "my guinea pig" when I tested this stuff out on her. 

Basically, I conditioned her to wheek for food whenever she heard me say "That's right, that's correct!" and other doting language, Which was something stupid I'd do to pretend I had a conversation with her. She'd also wheek whenever she heard my mattress squeaking in the morning. There was a TON of things I conditioned her to do, which includes the common response to plastic bags.

But the funniest thing is that I conditioned *myself*. Even though my guinea pig is dead, whenever I hear a door squeak, or my mattress squeak, or a bird chirp, any type of squeaking, I instinctively will say "That's right, that's correct!" And I'll just keep on going for a while. It's a saddening reminder, but also cool!