Can Rats Play With Rats?

Rats produce vocalization when they're playing and when they 're being tickled. And if they want you to tickle them, they will make the sound. These sounds are so high pitched they normally can't be heard by the human ear. You have to manipulate the cording to hear how rats respond to ticklings. It really does seem to be a kind of an invitation to play,. But it may not just be a trivial thing. The more you tickle a baby rat when it's a baby, the more that rat will laugh as an adult. So you can potentiate laughter, the rats tell us....