Tickling rats. It sounds like a euphemism for something not quite acceptable for print but is, in fact, science. While it may not be the most technologically innovative method of research, scientists ...

March 31, 2005 — -- We may know what kinds of things make us laugh -- slapstick, a clever pun, an inside joke with an old friend, an April Fools' gag -- but just what are those strange sounds we ...

A new study is linking brain behavior to silly playtime practices. And they have lab rats laughing out loud to prove it.In the video above, you can hear tiny high-pitched giggles from a rat being ...

Tummy-tickling causes rats to break out in giggles and jump with joy - but only when they are happy, a study has shown. Scientists confirmed the ticklishness of rats in experiments that involved ...

Apes often make weird sounds when they're tickled, and some researchers now say these pants and hoots truly are related to human laughter. That's the conclusion of a new study in the journal Current ...