How Do Festive Cracker Gags Do to The Brain?

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

This one-liner is met by moans that echo through a warehouse in London.

We're at a joke-testing session with a company that makes products for social events. Its repertoire features Christmas crackers.

The firm's owner smiles, nearly apologetically at the gag. But the joke has made the cut and will feature in upcoming crackers.

"The success is gauged by the gag by the volume of moans and the loudness of the groans around the table," she explains.

The key to a good Christmas cracker pun is not the same as a stand-up gag in itself. It is all about the setting - in this instance, the communal laughter of the holiday dinner table with elders, children and possibly neighbours.

"The goal is for the joke to be a thing that unites the child in harmony with the grandparent," she states.

The Science Of Communal Amusement

Coming together to enjoy communal amusement is not only ancient, scientists say, it is likely to be older than humanity.

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

Communal amusement, she says, aids in make and maintain social connections between people.

Scientists have found that a lack of such interactions can significantly damage mental and physical health.

"Those you talk to, and share laughter with, it results in increased levels of endorphin uptake," the professor adds.

Endorphins are the brain's "happy chemicals" and are released both to reduce tension and discomfort and in reaction to pleasurable experiences, such as chuckling with friends over a particularly awful festive cracker joke.

"It's not simply chuckling at a foolish joke with a holiday cracker," she states. "You are actually performing a lot of the truly important work of making, maintaining the social bonds you have with the people you care about."

What Happens In the Brain?

But what is actually taking place within the brain when we listen to a joke?

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

Using functional magnetic resonance imaging (fMRI), a kind of neural imager which indicates which parts of the mind are working harder, scientists have been able to map the areas that receive more blood flow.

Testing entails scanning the brains of healthy participants and then subjecting them to a collection of funny words, paired with either a neutral sound, or pre-recorded chuckles.

"During the study we got a really interesting pattern of activation," says the professor.

A joke stimulates not just the areas of the brain in charge of hearing and understanding speech, but also neural areas associated with both preparation and starting motion and those linked to sight and memory.

Put these elements together, and individuals hearing a pun have a complex series of brain reactions that underpin the laughter we hear.

The Contagious Nature of Laughter

Researchers discovered that when a funny phrase is paired with chuckles there is a greater response in the mind than the identical word when followed by a neutral sound.

"This was in parts of the brain that you would employ to contort your expression into a grin or a chuckle," the professor says.

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

Laughter, according to the expert, can be infectious.

So what does this imply for the chuckles found around a holiday table?

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

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

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

The Search for the Perfect Festive Pun

Is it possible to find the perfect joke?

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

In 2001, a psychologist set up a research search for the world's most humorous gag.

Over 40,000 jokes later, with scores lodged by hundreds of thousands of participants globally, he has a clearer idea than many as to what works and what does not.

The perfect Christmas cracker pun must be brief, he explains.

"They must also be poor jokes, puns that cause us to moan," he adds.

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

"This is because if nobody finds it funny – it's the joke's fault, not your own.

"The fascinating part about the holiday cracker jokes is that not one person find them funny.

"It creates a common experience at the table and I believe it's lovely."