🔗 Share this article

"How much did Father Christmas's sled cost? Nothing, it was on the house."

This one-liner is greeted with groans that resonate through a warehouse in London.

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

The company's owner grins, nearly sheepishly at the gag. But the joke has been selected and will feature in future crackers.

"You measure the gag by the volume of groans and the intensity of the groans around the table," the founder says.

The key to a good Christmas cracker pun is not the identical as a good joke per se. It is entirely about the context - in this instance, the shared amusement of the Christmas meal with grandparents, children and potentially friends.

"The goal is for the gag to be a thing that brings the eight-year-old in harmony with the grandparent," she adds.

The Science Of Communal Laughter

Coming together to experience communal amusement is not only nothing new, experts argue, it is probably to be older than humanity.

"So when you are laughing with others around the holiday dinner you are dropping into what's very likely a truly ancient mammal play sound," explains a neuroscience expert.

Communal laughter, she explains, helps make and maintain social connections between people.

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

"Those you talk to, and laugh with, it leads to increased levels of endorphin 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 experiences, such as chuckling with loved ones over a particularly terrible Christmas cracker joke.

"You're not just chuckling at a silly joke with a Christmas cracker," she states. "You are in fact performing a lot of the really vital work of making, maintaining the social bonds you have with those you love."

What Occurs In the Brain?

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

An awful lot occurs in reaction to humour, it transpires.

Using functional magnetic resonance imaging (fMRI), a kind of neural imager which shows which parts of the mind are more active, researchers have been able to map the regions that get more blood flow.

The research entails scanning the minds of healthy participants and then subjecting them to a database of humorous words, paired with either a non-emotional sound, or pre-recorded chuckles.

"During the study we observed a really interesting activation pattern of neural activity," says the neuroscientist.

A joke activates not just the parts of the mind in charge of auditory processing and understanding speech, but also brain regions involved in both preparation and starting motion and those involved in sight and memory.

Put all of this as a whole, and people listening to a joke have a complex series of brain responses that underpin the amusement we experience.

The Contagious Power of Chuckles

Scientists discovered that when a humorous phrase is paired with laughter there is a greater reaction 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 move your face into a grin or a laugh," the professor says.

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

Amusement, says the professor, can be contagious.

So what does this imply for the chuckles found at a Christmas table?

"You laugh harder when you are familiar with others," she notes, "and you laugh more when you like them or love them."

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

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

The Quest for the Perfect Cracker Joke

Is it possible to discover the perfect gag?

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

Years ago, a psychologist established a scientific search for the world's funniest gag.

More than 40,000 gags submitted, with scores lodged by hundreds of thousands of participants around the world, he has a better understanding than many as to what succeeds and what fails.

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

"But they also need to be poor gags, puns that make us moan," he adds.

The more "terrible" the joke, he says the better.

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

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

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