What Do Festive Cracker Gags Affect Our Brains?

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

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

We're at a humor-evaluation session with a firm that makes products for social events. Its catalogue includes festive crackers.

The firm's owner smiles, almost apologetically at the gag. But the joke has made the cut and will feature in upcoming crackers.

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

The secret to a good holiday cracker pun is not the identical as a stand-up gag in itself. It is entirely about the setting - in this case, the shared laughter of the Christmas dinner table with elders, children and potentially neighbours.

"The goal is for the joke to be something that brings the eight-year-old together with the grandparent," she adds.

The Neuroscience Behind Shared Amusement

Coming together to enjoy shared amusement is not only nothing new, experts say, it is probably to be pre-human.

"Therefore when you are laughing with others at the Christmas dinner you are dropping into what's very likely a truly ancient mammalian social vocalisation," says a professor.

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

Scientists have discovered that a lack of these interactions can significantly damage mental and physical health.

"The people you converse with, and laugh with, it leads to enhanced amounts of endorphin uptake," she continues.

These natural chemicals are the brain's "happy chemicals" and are released both to reduce tension and discomfort and in reaction to enjoyable activities, such as chuckling with loved ones over a truly awful Christmas cracker joke.

"You're not just chuckling at a foolish pun with a Christmas cracker," she says. "You are actually performing a lot of the really vital work of building, preserving the social bonds you have with those you love."

What Occurs In the Brain?

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

A tremendous amount occurs in reaction to comedy, it transpires.

Using brain scanning technology, a type of brain scanner which shows which parts of the brain are more active, researchers have been able to chart the areas that get more blood flow.

The research involves scanning the brains of volunteer subjects and then exposing them to a database of funny phrases, paired with either a non-emotional sound, or pre-recorded chuckles.

"During the study we observed a really fascinating pattern of neural activity," notes the professor.

A joke activates not just the areas of the brain responsible for hearing and understanding speech, but also brain regions involved in both preparation and initiating motion and those linked to sight and recall.

Put all of this together, and people listening to a joke have a sophisticated series of brain responses that support the amusement we experience.

The Contagious Power of Laughter

Scientists discovered that when a funny phrase is paired with laughter there is a greater response in the mind than the identical word when followed by a non-emotional sound.

"This was in parts of the mind that you would employ to contort your expression into a smile or a chuckle," she explains.

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

Laughter, says the expert, can be contagious.

So what does this imply for the laughter found at a Christmas gathering?

"People laugh more when you know people," she notes, "and laughter increases more when you like them or love them."

When it comes to Christmas cracker jokes, she explains, the feel-good factor is more probable to be triggered not by the gag itself, but from the reaction to it.

"It's the laughter. The gag is the terrible Christmas cracker pun, and it's just a reason to laugh as a group."

The Search for the Perfect Cracker Joke

Is it possible to find the perfect joke?

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

Years ago, a psychologist established a scientific project for the world's most humorous gag.

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

The perfect Christmas cracker joke must be short, he explains.

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

The increasingly "awful" the joke, he says the better.

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

"The fascinating part about the Christmas cracker puns is that not one person considers them humorous.

"That's a shared moment at the gathering and I believe it's wonderful."