Neuroscientist Robert Provine is studying laughter at the University of Maryland Baltimore County.
The prof says laughing is a form of primal communication, common to people, apes, dogs and even rats.
And he says the ha-ha-ha of laughing is the same in all languages from Mandarin to English.
But the laughter researchers get serious when they talk about money.
Northwestern University's Jeffrey Burgdorf say it's tough getting funding to study laughing.
So, he calls his research the study of "positive emotional response."
