Acoustic and perceptual effects of articulation exercises in transwomen

Summary Purpose This study measured the impact of articulation exercises using a cork and articulation exercises for lip spreading on the formant frequencies of vowels and listener perceptions of femininity in transgender women. Methods Thirteen transgender women were recorded before and after the cork exercise and before and after the lip spreading exercise. Speech samples included continuous speech during reading and were analyzed using Praat software. Vowel formant frequencies (F1, F2, F3, F4, F5) and vowel space were determined. A listening experiment was organized using naive cisgender women and cisgender men rating audio samples of continuous speech. Masculinity/femininity, vocal quality and age were rated, using a visual analogue scale (VAS). Results Concerning vowel formant frequencies, F2 /a/ and F5 /u/ significantly increased after the lip spreading exercise, as well as F3 /a/, F3 /u/ and F4 /a/ after the cork exercise. The lip spreading exercise had more impact on the F2 /a/ than the cork exercise. Vowel space did not change after the exercises. The fundamental frequency (fo) increased simultaneously during both exercises. Both articulation exercises were associated with significantly increased listener perceptions of femininity of the voice. Conclusion Subtle changes in formant frequencies can be observed after performing articulation exercises, but not in every formant frequency or vowel. Cisgender listeners rated the speech of the transgender women more feminine after the exercises. Further research with a more extensive therapy program and listening experiment is needed to examine these preliminary findings.