The science of laughter and why it's good for us

Laughter is a surprisingly complicated process, engaging multiple regions of the brain and the body.

(CNN)Everyone likes a good belly laugh from time to time, and science supports that feeling.

Studies have shown that laughing is linked to our physical, emotional and mental well-being -- even our relationships.
Here are some things you might not know about laughter.

    Laughter was a survival tool

      Laughter is thought to have evolved as a form of social bonding in animals and as a way to express playful intention. Many mammals laugh when they are tickled and when they engage in physical play.
      But humans don't need a physical trigger to laugh -- though generally we can't help but laugh if we're tickled.
      Janet Gibson, a professor emerita of cognitive psychology at Grinnell College in Iowa, said that laughter evolved in humans as a communication signal.
        Hundreds of years ago, "laughter was the glue that kept the group together," she told CNN Chief Medical Correspondent Dr. Sanjay Gupta on his Chasing Life podcast.
        "The idea was that laughter was an external signal that can tell the group everything is OK, we can relax. (There is) no need to be anxious or threatened by what's happening around us. And so this would really be a great survival tool for groups of humans," she explained.
        "And the belief is, is that over the centuries, the brain kept these connections so that we now laugh when ... we hear things that are relaxing, funny, surprising, amusing."
        Anthropologists think that laughter is universal, but that doesn't mean every culture finds the same things funny.

        Laughing is a primitive noise

        Laughter is a surprisingly complicated process, engaging multiple regions of the brain and the body.
        The frontal lobe is thought to help you interpret the various bits of information you receive -- the sounds and images -- and then it decides whether they are funny. That triggers an emotional response in the limbic system, which controls feelings like pleasure and fear and that in turn stimulates your motor cortex, explained Gupta in the podcast.
        Why swearing is a sign of intelligence, helps manage pain and more