i work as a stand up comedian. Nothing is more rewarding than to performs in front of a live audience, usually speaking directly to them.
That's great, I was wondering if there is anything in the brain that helps with comedy?
It has nothing to do with the brain. All you have to do is to  recite a grouping of humorous stories, jokes and one-liners typically called a monologue, routine or act.
That's great, does one have to learn a special skill to become a professional comedian?
Not really, as long as you can  provide a steady stream of laughs
Fantastic, when did people start to use comedy as a form of entertainment?
I am not sure about the time but it can be traced back to the origin as found in the Ancient Greece
what body organ helps with comedy?
No body organ help with comedy. But you can cal it hard, lonely and vicious acts