🔗 Share this article

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

This one-liner is met by 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 joke has been selected and will feature in upcoming crackers.

"You measure the gag by the number of groans and the intensity of the groans around the table," the founder says.

The secret to a great Christmas cracker joke is not the identical as a good joke in itself. It is all about the context - in this case, the communal laughter of the Christmas dinner table with elders, children and possibly friends.

"The goal is for the joke to be a thing that unites the child in harmony with the 80-year-old," she states.

The Science Of Shared Amusement

Coming together to experience shared laughter is not only nothing new, scientists argue, it is probably to be older than humanity.

"So when you are laughing with people around the Christmas dinner you are engaging in what's almost certainly a truly ancient mammal play vocalisation," says a professor.

Shared laughter, she says, aids in make and maintain social connections between people.

Researchers have discovered that a lack of these social exchanges can significantly damage both psychological and bodily health.

"The people you converse with, and share laughter with, it leads to increased amounts of 'happy chemical' release," the professor continues.

These natural chemicals are the body's "happy chemicals" and are produced both to alleviate tension and discomfort and in reaction to enjoyable activities, such as laughing with loved ones over a particularly awful festive cracker gag.

"You're not just chuckling at a foolish joke with a Christmas cracker," she says. "You are in fact performing a lot of the truly vital task of building, preserving the connections you have with the people you care about."

What Happens In the Mind?

But what is actually happening inside the brain when we listen to a gag?

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

Using functional magnetic resonance imaging (fMRI), a type of brain scanner which indicates which parts of the mind are working harder, researchers have been able to chart the regions that receive more blood.

The research involves scanning the brains of healthy subjects and then subjecting them to a collection of funny words, paired with either a neutral sound, or pre-recorded laughter.

"In the scanner we observed a very fascinating pattern of neural activity," says the professor.

A gag activates not just the areas of the mind responsible for auditory processing and interpreting speech, but also neural regions associated with both planning and initiating motion and those involved in vision and memory.

Put all of this as a whole, and people listening to a joke have a sophisticated set of neural responses that support the amusement we hear.

The Infectious Nature of Chuckles

Scientists found that when a funny word is combined with laughter there is a stronger response in the mind than the identical word when accompanied by a non-emotional sound.

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

It indicates we are not just responding to humorous jokes, they are responding to the laughter that follows them.

Laughter, according to the professor, can be contagious.

So what does this imply for the chuckles heard around a Christmas gathering?

"You laugh more when you know others," she notes, "and you laugh more when you like them or care for them."

When it comes to festive cracker jokes, she says, the positive factor is more probable to be caused not by the gag in itself, but from the reaction to it.

"The laughter is key. The joke is the terrible holiday cracker joke, and it's just a reason to chuckle as a group."

The Search for the Perfect Cracker Joke

Is it possible to find the perfect joke?

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

Years ago, a psychologist established a scientific search for the planet's most humorous gag.

Over 40,000 gags submitted, with ratings provided by 350,000 participants globally, he has a clearer idea than most as to what works and what fails.

The perfect festive cracker joke needs to be short, he explains.

"But they also be bad jokes, puns that make us groan," he adds.

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

"This is because if no-one finds it funny – it's the gag's fault, not yours.

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

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