People Adapt to Personal Singular They Through Exposure

Although they is often considered a plural pronoun (e.g., "Liz and Will went to the library. They borrowed a textbook"), it is increasingly used as a singular pronoun for individuals whose personal pronouns are they/them (e.g., "Alex went to the store. They bought a sandwich"), a usage we call personal they. This usage wasn't broadly available until relatively recently, but its increasing frequency requires comprehenders to identify a singular referent when appropriate. What mechanism accounts for this change? While one possibility is that explicit awareness can boost consideration of the singular meaning of they (Arnold et al., 2021), here we test the hypothesis that comprehension facility can be facilitated through exposure. In two experiments, participants listened to stories where they referred to either a singular character (Alex) or to two characters. Participants were more likely to choose the singular interpretations after singular exposure, consistent with evidence that adaptation affected on-line processing in a mouse-tracking task (Ye & Arnold, 2025). Results support the role of exposure as a mechanism for the increased availability of singular they interpretations.