Excerpted from Swearing Is Good for You, by Emma Byrne.

For a very long time, conventional wisdom held that swearing was not a useful response to pain. Many psychologists believed that swearing would actually make pain feel worse, thanks to a cognitive distortion known as catastrophizing. When we catastrophize we leap to the conclusion that the bad thing that is currently happening is the absolute worst thing. We’re usually catastrophizing when we say things like, “This is terrible! I just can’t!” Swearing was thought to reinforce that feeling of helplessness.

But this troubled Richard Stephens, a psychologist and author of Black Sheep: The Hidden Benefits of Being Bad, who wondered “why swearing, a supposedly maladaptive response to pain, is such a common pain response.” Like all of us, he’s hit his thumb with a hammer enough times to know that swearing seems to be an unavoidable response. So he set out to find out whether swearing really does make pain feel worse.

Somehow, he persuaded 67 of his undergraduate students at Keele University in Staffordshire, England, to stick their hands in ice-cold water for as long as they could stand, and do it not just once but twice, once while swearing and once not. (The Keele University School of Psychology Research Ethics Committee approved the study, which might be something to ponder if you’re choosing your future alma mater.) The thinking behind the experiment was as follows: If swearing is so maladaptive, then the volunteers would give up much faster while they were cursing than if they were saying another, neutral word.

Excerpted from Swearing Is Good for You, by Emma Byrne. Available on Amazon.

To make it a fair test, the students were allowed only one swear word and one neutral word and the order of the swearing and neutral immersions was randomized. Stephens asked them for five words they would use if they dropped a hammer on their thumb and five words to describe a table. Then he took the first swear word that appeared in the first list and its counterpart from the second list. When I did the experiment, my words were: “arrgh, no, fuck, bugger, shit” and “flat, wooden, sturdy, shiny, useful,” which meant saying “fuck” in one trial and “sturdy” in the other.

The results could best be summarized by the phrase “Maladaptive, my ass!” It turned out that, when they were swearing, the intrepid volunteers could keep their hands in the water nearly 50 percent longer as when they used their non-cursing, table-based adjectives. Not only that, while they were swearing the volunteers’ heart rates went up and their perception of pain went down. In other words, the volunteers experienced less pain while swearing. It’s an easy experiment to try for yourself at home, or at a party if you have the right kind of friends. All you need is a bowl of ice water and a stopwatch. So why wasn’t this experiment done soon after the invention of the ice cube?

about the author Emma Byrne has written on science, language, and society for the BBC, Science, the BMJ, the Financial Times, and Forbes. She lives in London.

“Pain used to be thought of as a purely biological phenomenon, but actually pain is very much psychological. The same level of injury will hurt more or less in different circumstances,” Stephens says. We know, for example, that if male volunteers are asked to rate how painful a stimulus is, most of them will say it hurts less if the person collecting the data is a woman. Pain isn’t a simple relationship between the intensity of a stimulus and the severity of your response. Circumstances, your personality, your mood, even the experience of previous pain all affect the way we experience a physical hurt.

What Does Swearing Do to the Brain?

When studying the effect of swearing, Stephens doesn’t assume that swearing has induced a particular emotional state in all of his volunteers. Instead he, like many other psychologists, quantifies the degree of each volunteer’s arousal using their heart rate and galvanic skin response (roughly speaking, a measure of how sweaty-palmed you are; researchers attach small electrodes to volunteers’ fingertips. These detect levels of stress, fear, anxiety, or excitement).