Semiautomatic measures of velar stop closure location using the EdgeTrak software.

Previous work has found a strong correlation between the frontness of closure location for velar stops (measured manually from ultrasound images) and the frontness of the following vowel (measured by F2). In this study, semi automatic measures of tongue frontness during a velar closure were made. Tongue edge traces were made using the EDGETRAK software (Li et al., 2005, Clinical Linguistics and Phonetics, 545–554). Frontness was then quantified from these traces using three different measures: Bressman’s anteriority index (Bressman et al., 2005, Clinical Linguistics and Phonetics, 573–588), a modified version of the anteriority index created for this study, and a measure of the center of mass of the tongue created for this study. When compared to the original manual measures, the modified anteriority index correlated most highly with both the manual measurement of the consonant closure location and also with F2 of the following vowel. The modified anteriority index uses an angle based weight in the anteri...