Many bilingual individuals say they feel like a different person depending on which language they are speaking. A new study lends credence to their claims.

Nairán Ramírez-Esparza, a psychology doctoral student at the University of Texas at Austin, charted the personality traits of 225 Spanish/English bilingual subjects in both the U.S. and Mexico as they responded to questions presented in each language. Ramírez-Esparza and her colleagues found three significant differences: when using English, the bilinguals were more extraverted, agreeable and conscientious than when using Spanish.

Researchers have shown before that bicultural individuals can assume different roles depending on environmental cues. But the new results indicate that character itself can morph. “To show that changes in personality — albeit modest ones — can be triggered by something as subtle as the language you’re speaking suggests that personality is more malleable than is widely expected,” Ramírez-Esparza says. Switching tongues will not turn a bookworm into a party animal, but the variances are noticeable nonetheless.

The investigators ruled out differences between translations of the questions as possible confounding factors, and all subjects were truly fluent. “The results are significant in that they document the contextual nature of personality,” says Daniel Heller, a psychology professor at the University of Waterloo in Ontario not involved in the research. “The U.S. is becoming increasingly bicultural and bilingual,” Ramírez-Esparza points out, “so it is important that we start to develop a better understanding of bicultural minds.”