🔗 Share this article

"How much did Father Christmas's sled cost? Zero, it was on the house."

This quip is met by groans that resonate through a warehouse in London.

This describes a joke-testing session with a company that makes products for social events. Its repertoire features festive crackers.

The firm's founder grins, nearly apologetically at the joke. But the pun has made the cut and will feature in future crackers.

"You measure the gag by the number of moans and the loudness of the groans at the table," she says.

The secret to a good holiday cracker joke is not the same as a good gag per se. It is all about the setting - in this instance, the communal laughter of the Christmas dinner table with elders, children and possibly neighbours.

"You want the gag to be a thing that unites the eight-year-old together with the grandparent," she states.

The Science Of Communal Laughter

Coming together to experience communal amusement is not only nothing new, scientists say, it is likely to be pre-human.

"Therefore when you are laughing with people at the holiday dinner you are dropping into what's very likely a truly primordial mammal social sound," says a neuroscience expert.

Communal laughter, she says, aids in forge and strengthen social bonds between individuals.

Scientists have found that a absence of such interactions can significantly harm mental and physical well-being.

"Those you converse with, and laugh with, it leads to enhanced amounts of 'happy chemical' release," she continues.

Endorphins are the brain's "feel-good compounds" and are released both to reduce stress and pain and in reaction to enjoyable activities, such as laughing with loved ones over a truly terrible festive cracker joke.

"You're not just chuckling at a foolish pun with a holiday cracker," the expert says. "You are actually performing a lot of the really important task of building, preserving the social bonds you have with those you love."

Which Occurs Inside the Brain?

But what is truly happening inside the mind when we hear a joke?

An awful lot occurs in response to humour, it turns out.

Using brain scanning technology, a kind of brain scanner which indicates which parts of the mind are more active, researchers have been able to chart the regions that get more blood.

The research involves scanning the brains of healthy subjects and then exposing them to a database of funny words, accompanied by either a neutral sound, or recorded laughter.

"During the study we got a really interesting activation pattern of neural activity," notes the professor.

A joke activates not just the parts of the brain responsible for hearing and understanding language, but also brain regions involved in both planning and starting movement and those involved in sight and memory.

Combine these elements together, and people listening to a pun have a sophisticated series of brain responses that support the laughter we hear.

The Contagious Power of Chuckles

Scientists discovered that when a humorous word is combined with chuckles there is a greater reaction in the brain than the same word when accompanied by a non-emotional sound.

"This activation occurred in areas of the brain that you would employ to contort your expression into a smile or a laugh," she says.

It indicates we are not just responding to humorous jokes, they are responding to the amusement that accompanies them.

Amusement, says the expert, can be contagious.

So what does this mean for the chuckles found at a Christmas gathering?

"People laugh harder when you are familiar with others," she notes, "and you laugh more when you are fond of them or love them."

When it comes to festive cracker jokes, she explains, the feel-good effect is more probable to be caused not by the gag in itself, but from the reaction to it.

"The laughter is key. The gag is the dreadful holiday cracker joke, and it's just a reason to chuckle as a group."

The Quest for the Ideal Festive Pun

Will we ever discover the ultimate gag?

Probably not, but that has not prevented experts from trying to.

Years ago, a professor set up a scientific search for the planet's most humorous gag.

Over tens of thousands of gags later, with scores provided by hundreds of thousands of people around the world, he has a clearer idea than many as to what works and what fails.

The ideal Christmas cracker pun must be short, he explains.

"But they also need to be bad gags, jokes that make us moan," he continues.

The increasingly "awful" the gag, he states the more effective.

"This is because if no-one finds it funny – it's the joke's fault, not your own.

"What's interesting about the Christmas cracker jokes is that not one person find them funny.

"It creates a shared experience around the gathering and I think it's lovely."