Exploring the Age Effects on European Portuguese Vowel Production: An Ultrasound Study

For aging speech, there is limited knowledge regarding the articulatory adjustments underlying the acoustic findings observed in previous studies. In order to investigate the age-related articulatory differences in European Portuguese (EP) vowels, the present study analyzes the tongue configuration of the nine EP oral vowels (isolated context and pseudoword context) produced by 10 female speakers of two different age groups (young and old). From the tongue contours automatically segmented from the US images and manually revised, the parameters (tongue height and tongue advancement) were extracted. The results suggest that the tongue tends to be higher and more advanced for the older females compared to the younger ones for almost all vowels. Thus, the vowel articulatory space tends to be higher, advanced, and bigger with age. For older females, unlike younger females that presented a sharp reduction in the articulatory vowel space in disyllabic sequences, the vowel space tends to be more advanced for isolated vowels compared with vowels produced in disyllabic sequences. This study extends our pilot research by reporting articulatory data from more speakers based on an improved automatic method of tongue contours tracing, and it performs an inter-speaker comparison through the application of a novel normalization procedure.