Why do we laugh?

Our recent Friday Family Movie Nights have entailed watching about 30 minutes of Mary Poppins before bed.  It's great fun, and reminds me of the days when Ian was 2 years old and could sing along with the soundtrack on the cassette in the car.  He says he doesn't remember most of them, but if we keep watching the movie over and over again, his memory will be jogged and he'll be able to sing along with, "It's grand to be an Englishman in 1910, King Edward's on the throne it's the age of men!..."  and "We're merely soldiers in petticoats, shoulder to shoulder for women's votes.  Though we adore men individually, we agree that as a group their rather stupid..."

A song that I always enjoy?  "I Love to Laugh."  See below.

Have you ever wondered why we laugh?  I can think a few reasons.

• That was funny!  When I hear a joke, and it's pretty funny, I'll laugh.
• Nervous laughter.  As in, "I hope that's not true!"
• Embarrassed laughter. I'm in pain, beacuse I tripped up the stairs!
• You are out of context!  (Young kid wearing grown-up's clothes, etc.)

Here are a couple specific examples that I have noted this week:

• This week I was listening to a lawyer give a presentation where he chuckled to himself at the end of every sentence.  Not sure if he thought he was saying something funny or if he was incredulous that everyone else in the world had a dimmer intellect than him.
•  Today I was at business meetings where the presenter complained to tech support that the screen wasn’t working, and the tech support recommended that he push the "on" button, which of course worked, bringing laughter throughout the room.
• A different presenter once had the opportunity to record intro music playing the bass guitar for the Bill Cosby Show.  He person reading the "fun fact" in the introduction said bass like the fish and the room erupted in laughter.  I didn't laugh because I know it was at the poor reader's expense.

I recently read an article in Scientific American, written by William B. Keith, giving some of the basics for laughter.

1. The first requirement is the “play frame,” which puts a real-life event in a nonserious context and allows for an atypical psychological reaction.
2. Another crucial characteristic is incongruity, which can be seen in the improbable or inconsistent relation between the “punch line” and the “body” of a joke or experience.

This seems to be epitomized by slapstick comedy and America's Funniest Home Videos.  We know that everyone is going to be alright, because it's a comedy, right?

Here's another take on it, from MSNBC.  By Robert Provine, Ph.D

Contrary to folk wisdom, most laughter is not about humor; it is about relationships between people...We found that most laughter does not follow jokes. People laugh after a variety of statements such as “Hey John, where ya been?” “Here comes Mary,” “How did you do on the test?” and “Do you have a rubber band?”. These certainly aren’t jokes.

Curiously, laughter seldom interrupts the sentence structure of speech. It punctuates speech. We only laugh during pauses when we would cough or breathe.

lol. 

What about you?  Overactive funny bone?