It bonds workers, sheds light on the brain and pacifies us. Emma Byrne on the uses and paradoxes of swearing

When I was about nine years old, I was smacked for calling my little brother a “twat”.

I had no idea what a twat was – I thought it was just a silly way of saying “twit” – but that smack taught me that some words were more powerful than others and that I had to be careful how I used them.

Except that experience didn’t exactly cure me of swearing. In fact, it probably went some way towards piquing my fascination with it. Since then I’ve had a certain pride in my knack for colourful and well-timed profanity: being a woman in a male-dominated field, I rely on it to camouflage myself as one of the guys.

But what is swearing and why is it special? Is it the way that it sounds? Or the way that it feels when we say it? Thanks to a range of scientists, from Victorian surgeons to modern neuroscientists, we know a lot more about swearing than we used to.

For example, I’m definitely not the only person who uses swearing as a way of fitting in at work. On the contrary, research shows that swearing can help build teams in the workplace. From the factory floor to the operating theatre, scientists have shown that teams who share a vulgar lexicon tend to work more effectively together, feel closer and be more productive than those who don’t.

Swearing has also helped to develop the field of neuroscience because of its function as a barometer of our emotions. It has been used as a research tool for more than 150 years, helping us to understand the structure of the human brain, such as the role of the amygdala in the regulation of emotions.

Swearing primes us to think aggressive thoughts while making us less likely to be violent physically

Swearing has taught us a great deal about our minds, too. We know that people who learn a second language often find it less stressful to swear in their adopted tongue, which gives us an idea of the childhood developmental stages at which we learn emotions and taboos. Swearing also makes the heart beat faster and primes us to think aggressive thoughts while, paradoxically, making us less likely to be physically violent.

And swearing is a surprisingly flexible part of our linguistic repertoire. It reinvents itself from generation to generation as taboos shift. Profanity has even become part of the way we express positive feelings – we know that football fans use “fuck” just as frequently when they’re happy as when they are angry or frustrated.

That last finding is one of my own. With colleagues at City University, London, I’ve studied thousands of football fans and their bad language during big games. It’s no great surprise that football fans swear, but it isn’t anywhere near as aggressive as you might think – fans on Twitter almost never swear about their opponents and reserve their outbursts for players on their own team.

In researching and writing about swearing I’m not attempting to justify rudeness and aggression. Not at all. I certainly wouldn’t want profanities to become commonplace: swearing needs to maintain its emotional impact to be effective. We only need to look at the way it has changed over the past hundred years to see that, as some swear words become mild and ineffectual through overuse or shifting cultural values, we reach for other taboos to fill the gap.

That doesn’t mean swearing is always used as a vehicle for aggression or insult. Study after study has shown that swearing is as likely to be used in frustration with oneself, or in solidarity, or to amuse someone else. Either way, it is a complex social signal that is laden with emotional and cultural significance.

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