🔗 Share this article

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

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

This describes a humor-evaluation meeting with a company that makes products for social events. Its catalogue features Christmas crackers.

The firm's founder smiles, almost sheepishly at the joke. But the pun has made the cut and will appear in future crackers.

"The success is gauged by the joke by the number of groans and the intensity of the groans around the table," the founder says.

The secret to a good Christmas cracker joke is not the same as a stand-up joke per se. It is entirely about the context - in this case, the shared amusement of the Christmas meal with grandparents, kids and potentially neighbours.

"The goal is for the joke to be something that unites the eight-year-old in harmony with the 80-year-old," she adds.

The Neuroscience Of Shared Laughter

Coming together to experience shared laughter is not only nothing new, scientists argue, it is likely to be pre-human.

"Therefore when you are laughing with people around the holiday dinner you are engaging in what's very likely a truly ancient mammal social vocalisation," says a neuroscience expert.

Shared amusement, she explains, aids in forge and strengthen social connections between people.

Scientists have discovered that a absence of these interactions can seriously damage both psychological and bodily health.

"Those you converse with, and laugh with, it results in enhanced amounts of endorphin release," the professor adds.

Endorphins are the body's "happy chemicals" and are produced both to reduce stress and pain and in response to enjoyable activities, such as chuckling with loved ones over a particularly awful Christmas cracker gag.

"It's not simply chuckling at a foolish pun with a Christmas cracker," the expert says. "You are in fact performing a lot of the truly vital work of making, maintaining the social bonds you have with the people you care about."

Which Occurs Inside the Brain?

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

An awful lot happens in response to comedy, it turns out.

Employing brain scanning technology, a kind of neural imager which shows which areas of the brain are more active, scientists have been able to chart the regions that receive more blood.

Testing involves scanning the minds of volunteer subjects and then exposing them to a database of funny words, accompanied by either a non-emotional sound, or pre-recorded laughter.

"In the scanner we got a very interesting pattern of neural activity," notes the neuroscientist.

A gag activates not just the areas of the brain responsible for hearing and interpreting language, but also neural regions associated with both preparation and initiating movement and those linked to vision and memory.

Combine all of this together, and individuals listening to a pun have a complex series of brain responses that support the amusement we hear.

The Contagious Power of Laughter

Scientists found that when a funny word is combined with laughter there is a stronger reaction in the mind than the same word when followed by a non-emotional sound.

"This activation occurred in areas of the mind that you would use to move your face into a smile or a laugh," she explains.

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

Laughter, according to the professor, can be infectious.

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

"People laugh harder when you are familiar with others," she says, "and laughter increases more when you like them or care for them."

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

"The laughter is key. The joke is the dreadful holiday cracker pun, and it's just a pretext to laugh as a group."

The Search for the Ideal Cracker Joke

Is it possible to find the perfect gag?

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

In 2001, a psychologist established a scientific search for the world's most humorous gag.

Over tens of thousands of gags submitted, with ratings lodged by hundreds of thousands of people globally, he has a better idea than many as to what succeeds and what fails.

The perfect Christmas cracker pun needs to be short, he says.

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

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

"This is because if no-one laughs – it's the joke's shortcoming, not yours.

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

"That's a common moment at the table and I believe it's lovely."