Differences in Sibilant Perception between Gender Expansive and Cisgender Individuals

Acoustic cues of voice gender influence not only how people perceive the speaker's gender (e.g., whether that person is a man, woman, or non-binary) but also how they perceive certain phonemes produced by that person. One such sociophonetic cue is the [s]/[ʃ] distinction in English; which phoneme is perceived depends on the perceived gender of the speaker. Recent research has shown that gender expansive people differ from cisgender people in their perception of voice gender and thus, this could be reflected in their categorization of sibilants. Despite this, there has been no research to date on how gender expansive people categorize sibilants. Furthermore, while voice gender expression is often discussed within a biological context (e.g., vocal folds), voice extends to those who use other communication methods. The current study fills this gap by explicitly recruiting people of all genders and asking them to perform a sibilant categorization task using synthetic voices. The results show that cisgender and gender expansive people perceive synthetic sibilants differently, especially from a "nonbinary" synthetic voice. These results have implications for developing more inclusive speech technology for gender expansive individuals, in particular for nonbinary people who use speech-generating devices.