Articulation of vowel height in Taiwanese Vowels: An EMA study

Abstract

Whalen et al.’s (2010) ultrasound study has suggested that constriction degree “may be the best descriptor for height” in American English front vowels {i, ɪ, e, ɛ}. The present study took a further step, investigating the case of height and backness distinction in Taiwanese front and back vowels. Stimuli consisted in /CV/ sequences with V corresponding to one of the six vowels {i, e, a, ɔ, ɣ, u} (Southern variety). Five adult speakers were asked to repeat each sequence six times in random order. The articulatory data were collected using the Carstens AG500 EMA system. Our results show that vowel height and backness in Taiwanese vowels can be reliably differentiated as follows: (1) for front and central vowels, height is primarily distinguished by Tongue Body Constriction Degree (TBCD) (i>e>a) (less robustly by Tongue Tip Constriction Degree), whereas height distinction of back vowels is made in Tongue Dorsum Constriction Degree (TDCD) (u>ɣ>ɔ), (2) backness can be distinguished by Tongue Tip and Tongue Body Constriction Location. Therefore, Whalen et al.’s (2010) claim can be extended to back vowels as well (at least in Taiwanese). Furthermore, our results are compatible with Ladefoged’s (2001) “holistic” view of vowel height as long as his “highest point of the tongue” can be “locally” interpreted: TBCD for height of front and central vowels and TDCD for back vowels. In sum, the present study suggests that distinction in vowel height be relativized to different gestural constriction degree.