Earlier this spring the Billboard pop music chart marked a milestone of sorts. Three of its top 10 hits prominently featured the same four-letter word: Cee Lo Green’s “F**k You,” Pink’s “F**kin’ Perfect” and Enrique Iglesias’s “Tonight (I’m Lovin’ You),” where the curse word appeared in the chorus. What’s going on here?

When it comes to popular culture, experts say, swearwords make fans feel as though they are part of a select club. “There’s a power to the words because they make you feel as if you fit in, and they identify you as part of a specific demographic,” says Timothy Jay, a professor of psychology at the Massachusetts College of Liberal Arts who has studied swearing for decades. Brain mapping shows that when we yell a choice word in anger, the brain’s right hemisphere, which reacts to emergencies and helps us process emotion, kicks into gear. Additionally, we get a little goose from the limbic system, which regulates emotion and behavior.

Parental worries about the prevalence of bad language may be overblown. Although swearing appears to be everywhere, it is actually still quite rare. Even if kids are cursing at a younger age, foul language accounts for only 0.3 to 0.7 percent of our daily speech. Experimental psychologist Elisah D’Hooge and her colleagues at Ghent University in Belgium are attempting to explain why.

In a study to be published this June in the journal Psychological Science, her team reports that we have a “verbal self-monitor” between the mental production of speech and the actual uttering of words that keeps us from making mistakes even when we are distracted. Our self-monitor “cares about context” and is “especially sensitive” to intercept words that might be inappropriate in a particular social situation, D’Hooge says.

In one of her experiments studying the effect of crude words on the speed of speech, participants were shown a picture on which a neutral word appeared and then a taboo word. For example, a picture of a horseshoe was paired with the word “crab,” as well as with “slut.” The participants were then asked to name the pictures as quickly as possible. Results showed that participants paused longer but made fewer errors when naming the picture when a taboo word was superimposed. That means their verbal self-monitor was more “stringent” when encountering the offensive word, D’Hooge says.

Nevertheless, the monitor is flexible. In the 1940s, for example, saying “goddamn it” was a no-no, but it became more acceptable in the 1960s, when new words, such as the “f” word emerged as taboo. There will always be some situations in which our verbal self-monitor will go on high alert, showing its “context-sensitive” side. “It can be cool to use the ‘f’ word a lot when you’re a 16-year-old boy hanging out with your friends, but it will be a lot less cool to use the word in the presence of your mum,” D’Hooge observes. Unless, of course, she’s a pop singer.