Acoustic Measurement Behavior in Brazilian Individuals of Different Genders

Objective: This research not only corroborates the existence of acoustic distinctions among different gender identities but also underscores the need for a more inclusive and sensitive approach in studies related to speech acoustic analysis. The objective of this study was to describe the behavior of acoustic measurements in individuals of different genders, highlighting potential differences among the groups.

Methods: Cross-sectional study. Speech excerpts and sustained vowel emission from 47 individuals (11 cisgender women – CW, 11 transgender women – TW, 11 cisgender men – CM, seven transgender men – TM, and seven non-binary individuals – NB) were recorded and underwent extraction of 16 acoustic measures involving noise, perturbation, spectral, and cepstral analyses. Descriptive and inferential analysis were conducted using one-way ANOVA and Games-Howell post-hoc tests, considering p<0.05.

Results: Patterns of measurement behavior were observed among the groups: median fundamental frequency (F0) showed differences between CW and CM (p<0.001) and TW (p=0.025), TM with CW (p=0.002), and CW with TW (p=0.025); minimum F0 exhibited differences between CW and CM (p<0.001), TM (p=0.015), and TW (p=0.028); Jitter showed differences between CW and CM (p=0.005), NB (p=0.048), and TM (p=0.030); difference between the first two harmonics between CW and CM (p<0.001); Shimmer between CW and CM (p=0.022); breathiness index (ABI) between CM and CW (p=0.012); and harmonics-to-noise ratio (HNR) between CW and NB (p=0.015).

Conclusion: There is a pattern of acoustic measurement behavior based on the speaker's gender. The findings indicated significant disparities, previously recognized in the analysis of cisgender voices, particularly in fundamental frequency, where notable differences were observed between cisgender men and cis and transgender women, as well as between cisgender and transgender women. Furthermore, differences were identified in Jitter, Shimmer, breathiness index (ABI), and harmonics-to-noise ratio (HNR) measures among different gender groups.