Two articulographic studies: lip movement variability and exotic Swedish vowels
Johan Frid and Susanne Schötz, Lund University
At this seminar, we will report results from two ongoing articulatory studies. In the first study, we are examining inter-repetition variability of lip movements across repetitions of the same utterance as a function of age in Swedish speakers. Functional Data Analysis (FDA) and Spatiotemperal Index (STI). Lip movement data of 15-20 repetitions of a short Swedish phrase from 41 typically developed Swedish children and adults (23 females, 18 males, aged 5-31 years) were collected using three-dimensional articulography, and submitted to functional data analysis (FDA), a method for analysing variability in signals. For comparison, we also calculated another metric of variability; the spatiotemporal index (STI). Results showed moderate negative correlations between age and STI as well as the two FDA indices amplitude variability and phase (temporal) variability. Linear regression analysis indicated the largest effect for amplitude variability, and the smallest for phase variability, supporting the potential for factoring out different types of variability for kinetic measurements of lip movements.
The second study is an articulographic and acoustic pilot study of the realisation of the vowel /iː/ in two regional varieties of Swedish. The study was carried out within the new research project Exotic vowels in Swedish – an articulographic study of palatal vowels [VOKART], which aims at increasing the empirical knowledge of vowel production in general, and extending our knowledge of the articulatory dynamics of palatal vowels in Swedish in particular. Articulatory and acoustic recordings of two male speakers – one South Swedish with regular [iː] and one East Central (Standard) Swedish with “damped”, so called “Viby- coloured” [ɨː] – were analysed. Results showed that [ɨː] was pronounced further back with an overall lower tongue position, but with a higher position of the tongue tip than [iː]. Acoustic analysis showed a lower F2 for [ɨː] than [iː], indicating a more centralised vowel quality. These very tentative results will be followed up with larger studies within the project.