🔗 Share this article

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

This quip is met by moans that resonate through a storage facility in London.

We're at a humor-evaluation session with a firm that makes supplies for social events. Its catalogue features festive crackers.

The company's founder smiles, almost apologetically at the gag. But the joke has been selected and will feature in upcoming crackers.

"You measure the joke by the number of moans and the loudness of the groans at the table," the founder explains.

The secret to a great holiday cracker joke is not the identical as a good joke per se. It is entirely about the setting - in this instance, the communal laughter of the holiday meal with elders, kids and potentially friends.

"You want the joke to be something that unites the child together with the grandparent," she adds.

The Neuroscience Of Shared Laughter

Gathering to enjoy communal laughter is not only ancient, scientists argue, it is likely to be older than humanity.

"Therefore when you are laughing with people at the holiday table you are engaging in what's almost certainly a truly primordial mammal play sound," explains a neuroscience expert.

Communal laughter, she says, helps make and maintain social bonds between individuals.

Researchers have discovered that a lack of such interactions can significantly damage both psychological and bodily well-being.

"Those you talk to, and laugh with, it leads to increased levels of 'happy chemical' uptake," the professor adds.

Endorphins are the brain's "feel-good compounds" and are produced both to reduce tension and discomfort and in response to enjoyable activities, such as laughing with friends over a truly awful festive cracker gag.

"You're not just laughing at a foolish joke with a holiday cracker," the expert says. "You are in fact performing a lot of the truly important task of building, preserving the connections you have with the people you care about."

Which Happens Inside the Brain?

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

A tremendous amount happens in response to comedy, it turns out.

Employing brain scanning technology, a kind of brain scanner which indicates which parts of the mind are working harder, scientists have been able to map the regions that get more blood flow.

The research entails scanning the brains of volunteer participants and then exposing them to a database of humorous phrases, accompanied by either a non-emotional sound, or recorded laughter.

"In the scanner we got a really interesting activation pattern of neural activity," says the professor.

A joke activates not just the parts of the mind responsible for hearing and understanding speech, but also neural areas involved in both preparation and initiating movement and those involved in vision and recall.

Put all of this together, and individuals hearing a pun have a sophisticated set of brain reactions that underpin the laughter we hear.

The Infectious Nature of Chuckles

Scientists discovered that when a humorous phrase is combined with chuckles there is a stronger response in the mind than the same phrase when accompanied by a non-emotional sound.

"This activation occurred in parts of the brain that you would employ to contort your face into a smile or a chuckle," she explains.

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

Amusement, according to the professor, can be contagious.

So what does this imply for the laughter found around a Christmas gathering?

"People laugh more when you know people," she notes, "and laughter increases further when you like them or care for them."

When it comes to festive cracker jokes, she says, the positive effect is more likely to be caused not by the gag in itself, but from the response to it.

"It's the laughter. The gag is the dreadful Christmas cracker joke, and it's just a reason to laugh as a group."

The Quest for the Ideal Festive Pun

Is it possible to discover the ultimate joke?

Probably not, but that has not prevented researchers from attempting to.

Years ago, a psychologist established a scientific project for the world's funniest joke.

More than tens of thousands of gags submitted, with ratings lodged by 350,000 participants around the world, he has a clearer understanding than many as to what works and what does not.

The ideal Christmas cracker joke needs to be short, he explains.

"They must also be poor gags, puns that cause us to groan," he adds.

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

"This is because if no-one laughs – it's the gag's shortcoming, not your own.

"The fascinating part about the Christmas cracker puns is that none of us find them humorous.

"It creates a common moment at the table and I think it's lovely."