Not only did they seek out the researchers’ hands to get tickled, and emit ultrasonic calls that are considered the rat’s equivalent of laughter, they also made joyful leaps....
Those calls, along with the ability to record brain activity while playing with the rats, allowed a deeper investigation of rat tickling. The researchers first accustomed young rats to play and tickling, which the rats would invite. “They are very eager to be tickled,” said Dr. Brecht.
November 10, 2016
When you tickle them. Listen here.