Articulatory Strategies in Male and Female Vowel Production.

PURPOSE: This study investigates the articulatory strategies used by male and female speakers to produce vowel sounds.

METHOD: Secondary data analysis of a preexisting articulatory corpus was carried out. Dynamic midsagittal ultrasound and acoustic data from 36 speakers of Northern English (21 females and 15 males) were analyzed, representing 17 vowel phonemes in a controlled phonetic environment. Articulatory landmarks corresponding to the tongue root, dorsum, and mandibular short tendon were automatically labeled in the ultrasound image, and their dynamic displacement was analyzed using generalized additive mixed modeling. Dynamic formant trajectories for the first formant (F1) and the second formant (F2) were analyzed using the same method.

RESULTS: Significant articulatory differences were found between male and female speakers for several vowels. Increased tongue dorsum fronting and lowering were found for female goose and goat vowels. Greater jaw opening was found in female trap, start, square, dress, mouth, and lot, accompanied by greater dorsal retraction, compared with male speakers. For strut/foot, there was greater retraction of the tongue dorsum in males. For some vowels, for example, trap and dress, corresponding differences were detected in normalized formant trajectories, but the magnitude of the acoustic differences was typically very small, and in some cases, such as mouth and lot, no differences in normalized F1 or F2 were detected, despite underlying articulatory differences.

CONCLUSIONS: Many of the differences we find point to increased jaw opening and greater involvement of the jaw as an articulator in female speakers. This wider strategy affects the production of multiple vowels, but it only manifests acoustically in some cases, suggesting the role of generalization mechanisms. Clinical implications for gender-affirming speech therapy are discussed.