How Do Festive Cracker Puns Do to The Brain?

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

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

We're at a joke-testing meeting with a firm that makes products for social events. Its repertoire includes festive crackers.

The firm's owner grins, nearly sheepishly at the joke. But the joke has made the cut and will feature in future crackers.

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

The key to a good holiday cracker joke is not the same as a good gag in itself. It is entirely about the context - in this case, the shared laughter of the holiday dinner table with grandparents, children and possibly neighbours.

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

The Neuroscience Behind Shared Laughter

Coming together to experience communal amusement is not only nothing new, experts say, it is likely to be pre-human.

"So when you are laughing with others at the holiday dinner you are dropping into what's almost certainly a really ancient mammal play vocalisation," says a neuroscience expert.

Shared laughter, she explains, helps forge and strengthen social bonds between individuals.

Researchers have discovered that a lack of such interactions can seriously harm both psychological and bodily well-being.

"Those you talk to, and share laughter with, it results in enhanced amounts of endorphin release," the professor adds.

These natural chemicals are the body's "happy chemicals" and are released both to alleviate tension and discomfort and in response to pleasurable experiences, such as chuckling with loved ones over a truly awful Christmas cracker gag.

"You're not just laughing at a foolish pun with a holiday cracker," the expert states. "You are in fact doing a lot of the really important task of making, maintaining the connections you have with those you love."

What Occurs Inside the Brain?

But what is actually taking place within the brain when we hear a gag?

An awful lot happens in response to comedy, 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 map the regions that receive more blood.

Testing involves imaging the brains of healthy subjects and then subjecting them to a collection of humorous words, paired with either a non-emotional sound, or recorded laughter.

"During the study we got a very interesting pattern of neural activity," notes the professor.

A joke stimulates not just the areas of the mind in charge of auditory processing and interpreting speech, but also brain areas associated with both preparation and initiating motion and those linked to vision and recall.

Put these elements as a whole, and people hearing a joke have a sophisticated set of brain responses that underpin the laughter we experience.

The Infectious Power of Chuckles

Scientists found that when a funny phrase is combined with chuckles there is a stronger response in the mind than the identical phrase when followed by a neutral sound.

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

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

Amusement, says the expert, can be infectious.

So what does this imply for the laughter heard at a Christmas table?

"You laugh harder when you are familiar with people," she says, "and laughter increases further when you like them or care for them."

When it comes to Christmas cracker jokes, she explains, the positive factor is more probable to be caused not by the gag itself, but from the response to it.

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

The Quest for the Ideal Cracker Joke

Is it possible to find the ultimate gag?

Likely not, but that has not stopped experts from trying to.

Years ago, a professor established a research project for the planet's funniest joke.

More than 40,000 gags submitted, with ratings provided by 350,000 participants around the world, he has a better understanding than many as to what works and what fails.

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

"They must also need to be poor gags, puns that cause us to groan," he continues.

The increasingly "awful" the joke, he says the more effective.

"The reason is that if nobody finds it funny – 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 common moment at the table and I think it's wonderful."