In 1994, researchers noticed that when rats anticipated an opportunity to play, they would let out a series of squeaky chirps. These were high-pitched, measured at 50 kilohertz. The researchers began ...

The life of a lab rat is not usually pleasant. They are shocked, drugged, sliced, starved and crippled in the name of furthering scientific understanding, but one group of German rats have had the ...

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 ...

Need a good laugh? The feeling is pretty universal, according to researchers who tickled rats for the sake of science. When the animals received a 10-second tickle from a gloved hand, they responded ...