How Do Holiday Cracker Jokes Do to The Brain?

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

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

This describes a joke-testing meeting with a company that produces supplies for social events. Its catalogue features Christmas crackers.

The company's founder smiles, almost apologetically at the gag. But the pun has made the cut and will feature in future crackers.

"You measure the gag by the volume of moans and the intensity of the groans at the table," the founder explains.

The secret to a good Christmas cracker pun is not the identical as a stand-up joke per se. It is entirely about the setting - in this instance, the shared amusement of the holiday meal with elders, children and potentially neighbours.

"The goal is for the joke to be something that unites the child together with the grandparent," she adds.

The Neuroscience Behind Shared Amusement

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

"So when you are chuckling with people around the holiday table you are engaging in what's almost certainly a really ancient mammalian social vocalisation," says a professor.

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

Researchers have discovered that a lack of these interactions can significantly harm mental and physical health.

"Those you talk to, and laugh with, it results in increased amounts of endorphin release," the professor continues.

These natural chemicals are the body's "feel-good compounds" and are released both to reduce tension and discomfort and in response to pleasurable experiences, such as laughing with loved ones over a truly terrible Christmas cracker joke.

"You're not just chuckling at a foolish joke with a holiday cracker," she states. "You are in fact doing a lot of the truly important task of making, maintaining the social bonds you have with those you love."

What Occurs Inside the Brain?

But what is truly happening within the brain when we listen to a joke?

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

Using functional magnetic resonance imaging (fMRI), a kind of neural imager which shows which areas of the mind are working harder, scientists have been able to chart the areas that get more blood.

The research involves imaging the brains of healthy participants and then subjecting them to a collection of humorous phrases, accompanied by either a neutral sound, or recorded laughter.

"During the study we got a really fascinating activation pattern of activation," notes the neuroscientist.

A joke stimulates not just the areas of the mind responsible for auditory processing and interpreting speech, but also neural regions involved in both preparation and initiating motion and those involved in vision and memory.

Combine these elements as a whole, and people hearing a joke have a complex set of neural responses that support the laughter we hear.

The Contagious Nature of Laughter

Researchers found that when a humorous phrase is paired with chuckles there is a stronger response in the brain than the identical word when followed by a neutral sound.

"This activation occurred in areas of the brain that you would use to move your expression into a grin or a chuckle," she says.

It indicates we are not just responding to funny words, they are responding to the amusement that follows them.

Laughter, according to the professor, can be contagious.

So what does this mean for the chuckles heard around a Christmas table?

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

When it comes to Christmas cracker puns, she explains, the feel-good effect is more probable to be caused not by the joke itself, but from the response to it.

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

The Search for the Ideal Cracker Joke

Is it possible to discover the perfect gag?

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

In 2001, a psychologist established a scientific search for the world's funniest joke.

Over 40,000 jokes later, with scores lodged by hundreds of thousands of people globally, he has a clearer understanding than many as to what works and what fails.

The ideal Christmas cracker pun needs to be brief, he explains.

"They must also be poor gags, jokes that cause us to groan," he continues.

The more "terrible" the gag, he states the more effective.

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

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

"That's a shared experience around the gathering and I think it's lovely."