Sweden recently introduced a gender-neutral pronoun. Psychologists say it's already changing the way people think.

• Sweden added a gender-neutral pronoun, hen, to its dictionary in 2012, and it's since become part of everyday usage.
• To find out how the word has affected Swedish culture, US scientists asked native Swedes to identify a stick figure with a gender pronoun, and most of them went gender-neutral with hen.
• The pronoun was largely associated with neutrality, while the English singular "they/them," was associated with the masculine gender.
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Swedish people have had two gender pronouns for a long time: hon (she) and han (he). Then in 2012, along came hen.

The gender-neutral pronoun has since become a regular part of Swedish life - and according to new psychological research, it's changing the way people think.

How hen changed Sweden

According to Adam Rogers at Wired, hen has become commonplace.

While hen had been proposed by Swedish speakers as early as the 1960s, it didn't catch on until debate increased in the early 2010s. The tipping point seemed to come when a children's book called "Kivi and the Monster Dog" was published in 2012. Its writer, Jesper Lundqvist, referred to the book's main character using hen. The thing that set apart Lundqvist's book was the subtlety of gender in the book. While some Swedish children's books drew attention to a character's gender-neutrality by putting them in the face of adversity, Ludqvist's plot had nothing to do with gender.

The new word didn't come without controversy, however. One lifestyle publication, Nöjesguiden, decided to use hen exclusively, while a newspaper called Dagens Nyheter outlawed it altogether. But hen won in the end. Sweden's National Encyclopedia added the word later in 2012, and the Swedish Academy (the one that awards the Nobel Prize in literature) added it to their dictionary in 2014.

The experiment that put hen to the test

Seven years after "Kivi and the Monster Dog," Margit Tavits, a political scientist from Washington University in St. Louis, and Efrén Pérez, a political psychologist at the University of California, Los Angeles, devised an experiment to see if Swedes were really thinking in terms of hen.

In a new study published in "Proceedings of the National Academy of Sciences," over 2,000 native Swedes were presented with a cartoon featuring a stick figure, a cartoon balloon animal, and two thought bubbles connected to the person's head. The first thought bubble had three question marks, while the second, jagged-edged one had three exclamation points, allowing participants choose the words to describe the situation without any bias from the researchers. Not only was hen chosen over hon and han, but Swedes even devised entire stories using the gender-neutral pronoun.

The study suggests that new words can lead to new ideas in society. While the Swedes were generally against hen when it gained fame in 2012, by 2014 the majority was in favor of the word. In the US, the singular "they/them" - a feature of the English language since the 1300s - has recently caught on as a gender-neutral term, but not to the degree that hen has. As WIRED reports, one study found that English speakers using "they/them" associated the words with masculinity, while hen was associated with neutrality in Sweden.

Though hen was an invented pronoun, it's already slotting into everyday use.

"This word has no biological associations," Pérez said of hen. "It's from scratch. And it's performing the way some proponents argued it would."