The Impact of Holiday Cracker Gags Do to Our Brains?

"How much did Santa's sleigh cost? Nothing, it was on the house."

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

We're at a joke-testing meeting with a company that produces supplies for social events. Its catalogue includes festive crackers.

The firm's founder smiles, almost sheepishly at the joke. But the joke has been selected and will appear in upcoming crackers.

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

The key to a great Christmas cracker joke is not the same as a stand-up joke per se. It is entirely about the setting - in this instance, the communal amusement of the holiday meal with elders, kids and potentially neighbours.

"You want the joke to be something that unites the eight-year-old together with the 80-year-old," she adds.

The Neuroscience Behind Shared Amusement

Gathering to experience shared laughter is not only ancient, experts say, it is likely to be older than humanity.

"Therefore when you are laughing with others around the holiday dinner you are engaging in what's very likely a really primordial mammalian social vocalisation," says a professor.

Communal amusement, she explains, helps forge and strengthen social bonds between individuals.

Scientists have discovered that a absence of these social exchanges can seriously harm mental and physical well-being.

"Those you talk to, and share laughter with, it leads to increased amounts of endorphin uptake," the professor adds.

These natural chemicals are the body's "happy chemicals" and are released both to alleviate tension and discomfort and in response to enjoyable experiences, such as chuckling with friends over a truly terrible Christmas cracker joke.

"It's not simply laughing at a silly joke with a Christmas cracker," the expert states. "You are actually performing a lot of the really important task of making, maintaining the connections you have with the people you care about."

What Happens In the Brain?

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

A tremendous amount happens in response to humour, it transpires.

Employing brain scanning technology, a type of brain scanner which shows which areas of the brain are more active, scientists have been able to map the areas that receive more blood flow.

The research entails imaging the brains of volunteer subjects and then subjecting them to a database of humorous words, paired with either a non-emotional sound, or recorded chuckles.

"In the scanner we got a very interesting activation pattern of activation," says the neuroscientist.

A gag stimulates not just the areas of the brain responsible for hearing and interpreting language, but also neural areas associated with both preparation and starting motion and those involved in vision and memory.

Put these elements together, and people listening to a joke have a complex series of brain responses that support the amusement we hear.

The Contagious Nature of Laughter

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

"This was in areas of the mind that you would use to contort your face into a grin or a laugh," the professor says.

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

Laughter, says the expert, can be contagious.

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

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

When it comes to Christmas cracker puns, she says, the positive factor is more likely to be triggered not by the gag in itself, but from the response to it.

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

The Quest for the Ideal Festive Pun

Will we ever discover the ultimate gag?

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

In 2001, a professor established a research search for the planet's funniest joke.

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

The ideal festive cracker joke needs to be brief, he explains.

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

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

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

"What's interesting about the Christmas cracker puns is that none of us find them funny.

"That's a common moment at the gathering and I believe it's wonderful."