Re: What in the brain makes you laugh?

That is a very good question, and I'm sorry to say that I don't think that 
scientists have figured out a complete answer yet, but they are working on 
it. There are people who are doing research to find out how and why people 
laugh. There are even people who do research on what makes people 
ticklish. There are lots of things that can change whether or not we 
laugh, such as the place we are in or the people we are around, or the 
kind of mood we're in. 

There are many brain areas that we use to laugh at a joke. First we have 
to process the words of the joke. This takes place (in most people) on the 
left side of the brain, in areas that we know are important for 
understanding language. Then we have to understand what makes the joke 
funny. We do this using the frontal lobes (located near the forehead), 
though people don't have a clear understanding of how we decide if 
something is funny or not. Finally, after we get the joke (hopefully), the 
brain sends signals to motor cortex, a part of the brain that controls 
movement(near the top of the head), causing us to actually laugh. 

Another part of the brain that is important in causing laughter is called 
the "limbic system". The limbic system is made up of several different 
parts of the brain which all connect to each other. These parts of the 
brain are important for the emotions that people feel. If by accident 
something bad happens to these parts of the brain, people lose their 
ability to have feelings. I don't know if anyone has studied sense of 
humor in such cases, but my guess is that it would be affected too.

Finally, I'll give you two little bits of trivia that you might find 
interesting. 
1) Laughter is actually very good for you. People have shown that it can 
make your immune system stronger, and increase the number of cells in your 
body that help fight of diseases. This can keep you from getting sick as 
often.

2) Some people think that people may not be the only animals that laugh. 
Scientists who observe chimpanzees found that when young chimps are 
playing or are tickled by people, they make a funny sound that could be 
their version of laughter. It doesn't sound anything like people laughing 
though.  

I hope that answers your question. 

If you want more information on how laughter works, look here : 
http://www.howstuffworks.com/laughter.htm?printable=1

If you are looking for more laughs, check these pages out : 
http://www.users.bigpond.com/lander/default.htm 
http://www.owl.on.ca/owl/joke.html