What Do Holiday Cracker Jokes Affect The Brain?

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

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

We're at a humor-evaluation meeting with a company that produces products for gatherings. Its repertoire features Christmas crackers.

The company's founder smiles, nearly sheepishly at the joke. But the pun has made the cut and will feature in future crackers.

"You measure the joke by the number of groans and the intensity of the groans at the table," she says.

The key to a good holiday cracker pun is not the same as a stand-up joke per se. It is all about the setting - in this instance, the shared laughter of the Christmas meal with grandparents, children and possibly neighbours.

"You want the gag to be a thing that unites the child in harmony with the grandparent," she adds.

The Neuroscience Behind Communal Amusement

Coming together to experience shared amusement is not only ancient, experts argue, it is probably to be older than humanity.

"So when you are chuckling with others at the holiday dinner you are dropping into what's very likely a truly ancient mammalian social sound," says a neuroscience expert.

Communal laughter, she says, aids in forge and strengthen social bonds between individuals.

Researchers have discovered that a absence of these social exchanges can seriously damage mental and physical health.

"The people you converse with, and share laughter with, it results in increased amounts of endorphin release," she adds.

Endorphins are the brain's "happy chemicals" and are produced both to reduce tension and discomfort and in response to pleasurable activities, such as chuckling with loved ones over a particularly awful Christmas cracker joke.

"It's not simply laughing at a silly pun with a Christmas cracker," she states. "You are in fact performing a lot of the truly vital work of building, preserving the social bonds you have with those you love."

What Occurs In the Mind?

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

An awful lot happens in reaction to humour, it turns out.

Employing functional magnetic resonance imaging (fMRI), a type of brain scanner which shows which parts of the mind are working harder, researchers have been able to chart the areas that get more blood.

The research entails imaging the brains of healthy participants and then exposing them to a collection of funny words, accompanied by either a non-emotional sound, or pre-recorded chuckles.

"In the scanner we got a really fascinating activation pattern of activation," notes the neuroscientist.

A gag activates not just the areas of the brain responsible for hearing and understanding language, but also brain areas associated with both planning and initiating movement and those involved in sight and recall.

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

The Infectious Nature of Laughter

Scientists discovered that when a humorous word is paired with laughter there is a greater reaction in the brain than the identical phrase when followed by a neutral sound.

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

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

Amusement, says the professor, can be infectious.

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

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

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

"The laughter is key. The gag is the terrible holiday cracker joke, and it's just a pretext to chuckle together."

The Search for the Ideal Cracker Joke

Is it possible to find the perfect joke?

Probably not, but that has not stopped researchers from trying to.

In 2001, a professor established a scientific search for the planet's most humorous gag.

Over tens of thousands of jokes submitted, with ratings provided by 350,000 participants globally, he has a better idea than many as to what works and what does not.

The ideal Christmas cracker joke needs to be brief, he says.

"But they also be bad jokes, puns that cause us to groan," he continues.

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

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

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

"It creates a common moment around the table and I believe it's wonderful."