What Do Christmas Cracker Gags Affect Our Minds?

"How much did Father Christmas's sleigh cost? Zero, it was on the house."

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

We're at a joke-testing meeting with a company that produces products for gatherings. Its catalogue features Christmas crackers.

The company's founder grins, almost sheepishly at the joke. But the pun has been selected and will appear in future crackers.

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

The secret to a great holiday cracker joke is not the same as a good gag per se. It is entirely about the setting - in this case, the communal laughter of the holiday dinner table with grandparents, children and potentially friends.

"You want the joke to be a thing that brings the child in harmony with the 80-year-old," she states.

The Neuroscience Of Shared Laughter

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

"So when you are laughing with others around the Christmas dinner you are engaging in what's almost certainly a really primordial mammalian play vocalisation," says a neuroscience expert.

Communal laughter, she says, helps forge and strengthen social connections between individuals.

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

"Those you talk to, and share laughter with, it leads to increased levels of endorphin uptake," she adds.

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

"You're not just chuckling at a silly pun with a holiday cracker," the expert states. "You are in fact doing a lot of the truly vital task of building, preserving the connections you have with the people you care about."

What Occurs Inside the Mind?

But what is actually taking place inside the mind when we listen to a joke?

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

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

Testing entails scanning the minds of healthy subjects and then subjecting them to a collection of funny words, paired with either a non-emotional sound, or recorded chuckles.

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

A gag activates not just the parts of the mind in charge of auditory processing and understanding language, but also neural regions involved in both preparation and starting motion and those linked to sight and memory.

Put these elements together, and people listening to a joke have a complex series of neural reactions that support the amusement we experience.

The Contagious Nature of Laughter

Scientists found that when a humorous word is paired with chuckles there is a stronger reaction 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 employ to move your expression into a grin or a chuckle," she says.

It means people are not just reacting to funny jokes, they are reacting to the laughter that follows them.

Laughter, says the expert, can be infectious.

So what does this mean for the laughter found at a holiday gathering?

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

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

"It's the laughter. The gag is the dreadful holiday cracker pun, and it's just a pretext to chuckle as a group."

The Quest for the Ideal Cracker Joke

Will we ever discover the ultimate joke?

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

In 2001, a professor set up a research project for the planet's most humorous joke.

Over tens of thousands of jokes later, with ratings provided by 350,000 participants around the world, he has a better understanding than most as to what succeeds and what fails.

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

"They must also be bad jokes, jokes that cause us to groan," he adds.

The increasingly "awful" the gag, he states the better.

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

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

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