How Do Christmas Cracker Gags Influence Our Minds?

"What was the price did Santa's sled cost? Nothing, it was on the house."

This quip is greeted with moans that resonate through a warehouse in London.

This describes a humor-evaluation meeting with a company that produces supplies for gatherings. Its catalogue features festive crackers.

The company's founder smiles, nearly sheepishly at the joke. But the joke has made the cut and will feature in upcoming crackers.

"You measure the gag by the volume of groans and the loudness of the groans at the table," she explains.

The key to a good holiday cracker pun is not the same as a stand-up joke per se. It is entirely about the context - in this instance, the shared amusement of the holiday dinner table with grandparents, kids and potentially neighbours.

"You want the joke to be a thing that brings the child in harmony with the 80-year-old," she adds.

The Science Behind Communal Laughter

Coming together to enjoy shared laughter is not only nothing new, experts say, it is likely to be pre-human.

"So when you are chuckling with others around the holiday dinner you are engaging in what's almost certainly a really ancient mammal social vocalisation," explains a neuroscience expert.

Communal amusement, she explains, helps make and maintain social bonds between people.

Scientists have found that a lack of such social exchanges can seriously damage mental and physical well-being.

"The people you converse with, and laugh with, it leads to increased levels of endorphin uptake," she continues.

These natural chemicals are the body's "happy chemicals" and are released both to alleviate stress and pain and in reaction to enjoyable experiences, such as chuckling with loved ones over a truly terrible festive cracker joke.

"You're not just laughing at a foolish pun with a holiday cracker," the expert says. "You are actually performing a lot of the really vital work of building, preserving the connections you have with the people you care about."

What Happens Inside the Mind?

But what is truly taking place inside the brain when we hear a gag?

An awful lot happens in reaction to humour, it turns out.

Using brain scanning technology, a kind of brain scanner which indicates which areas of the brain are working harder, scientists have been able to chart the areas that receive more blood flow.

Testing entails imaging the minds of healthy participants and then exposing them to a database of humorous phrases, accompanied by either a neutral sound, or pre-recorded laughter.

"In the scanner we observed a very interesting activation pattern of activation," notes the neuroscientist.

A gag stimulates not just the areas of the brain responsible for auditory processing and interpreting language, but also neural areas involved in both preparation and initiating motion and those involved in sight and memory.

Combine all of this as a whole, and people hearing a joke have a sophisticated series of neural reactions that support the amusement we experience.

The Contagious Nature of Chuckles

Researchers discovered that when a funny phrase is paired with chuckles there is a stronger response in the brain than the same phrase when followed by a neutral sound.

"This was in areas of the brain that you would use to move your expression into a grin or a laugh," the professor explains.

It indicates people are not just responding to funny jokes, they are reacting to the amusement that accompanies them.

Amusement, according to the professor, can be infectious.

So what does this mean for the laughter heard at a Christmas table?

"People laugh more when you know others," she says, "and you laugh more when you are fond of them or love them."

When it comes to festive cracker puns, she explains, the feel-good factor is more likely to be caused not by the joke in itself, but from the reaction to it.

"The laughter is key. The gag is the dreadful Christmas cracker pun, and it's just a reason to laugh together."

The Quest for the Perfect Festive Pun

Is it possible to discover the ultimate gag?

Likely not, but that has not prevented researchers from trying to.

Years ago, a psychologist set up a scientific project for the world's most humorous joke.

Over 40,000 jokes submitted, with scores provided by hundreds of thousands of participants globally, he has a better understanding than many as to what succeeds and what fails.

The perfect festive cracker joke needs to be short, he says.

"They must also need to be bad gags, jokes that cause us to moan," he continues.

The increasingly "awful" the joke, he says the better.

"The reason is that if nobody finds it funny – it's the joke's shortcoming, not your own.

"The fascinating part about the Christmas cracker jokes is that not one person considers them funny.

"It creates a shared moment at the gathering and I believe it's wonderful."