The Impact of Holiday Cracker Gags Affect Our Minds?

"What was the price did Santa's sleigh cost? Zero, it was on the house."

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

This describes a joke-testing session with a firm that makes supplies for gatherings. Its repertoire features festive crackers.

The firm's owner smiles, almost sheepishly at the joke. But the pun has made the cut and will appear in future crackers.

"You measure the joke by the number of moans and the intensity of the groans around the table," the founder explains.

The secret to a great Christmas cracker joke is not the same as a good joke per se. It is entirely about the setting - in this instance, the shared laughter of the Christmas meal with elders, kids and possibly neighbours.

"You want the gag to be a thing that brings the eight-year-old together with the 80-year-old," she adds.

The Science Behind Communal Laughter

Gathering to enjoy communal amusement is not only nothing new, scientists argue, it is probably to be older than humanity.

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

Shared laughter, she says, aids in make and maintain social bonds between individuals.

Researchers have discovered that a lack of such social exchanges can significantly damage mental and physical health.

"The people you talk to, and share laughter with, it results in enhanced amounts of 'happy chemical' uptake," she adds.

Endorphins are the brain's "happy chemicals" and are released both to reduce tension and discomfort and in response to enjoyable experiences, such as chuckling with loved ones over a truly awful Christmas cracker gag.

"It's not simply chuckling at a silly pun with a Christmas cracker," the expert says. "You are in fact doing a lot of the truly vital work of building, preserving the connections you have with the people you care about."

Which Occurs In the Mind?

But what is truly happening within the mind when we hear a joke?

An awful lot occurs in response to humour, it transpires.

Using brain scanning technology, a type of neural imager which shows which parts of the mind are more active, researchers have been able to chart the regions that get more blood.

Testing entails scanning the brains of healthy subjects and then exposing them to a database of humorous phrases, accompanied by either a non-emotional sound, or pre-recorded chuckles.

"In the scanner we observed a really fascinating pattern of activation," says the neuroscientist.

A joke stimulates not just the parts of the brain in charge of hearing and understanding language, but also neural regions associated with both preparation and initiating motion and those linked to vision and recall.

Combine these elements as a whole, and people listening to a pun have a complex series of brain responses that support the amusement we experience.

The Contagious Nature of Laughter

Researchers found that when a humorous word is paired with laughter there is a greater response in the brain than the same word when followed by a neutral sound.

"This was in parts of the brain that you would use to contort your face into a smile or a chuckle," the professor says.

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

Amusement, says the expert, can be infectious.

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

"People laugh more when you are familiar with people," she says, "and you laugh further when you are fond of them or love them."

When it comes to Christmas cracker puns, she explains, the positive effect is more likely to be triggered not by the joke itself, but from the reaction to it.

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

The Search for the Perfect Cracker Joke

Is it possible to discover the ultimate joke?

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

In 2001, a psychologist set up a scientific search for the planet's funniest gag.

Over 40,000 gags submitted, with scores lodged by 350,000 people around the world, he has a better understanding than most as to what works and what fails.

The perfect festive cracker joke must be short, he says.

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

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

"This is because if nobody laughs – it's the gag's shortcoming, not yours.

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

"It creates a shared moment around the table and I believe it's lovely."