One way to find out is to watch the brain laugh. That’s pretty much what Dartmouth neuroscientist William Kelley did. He and his team had a number of volunteers watch an episode of Seinfeld while being monitored by an MRI–that’s a machine that allows researchers to see which parts of the brain are active at any given time. They then synchronized the MRI data with the laugh track to see how the brain changes when it’s registering something funny. There’s no one “funny center” in the brain–but the findings were pretty suggestive.