Speech Rate Effects on VOT in a 3-category Language: Evidence from Hakha Chin

This study probes the claim made under the Laryngeal Realism (Beckman et al. 2011/2013 among others), by investigating the effect of speech rate on VOT in Hakha Chin. The present study uses the diagnostics of changing the speech rate (Beckman et al. 2011), and examines whether it can be used to find the specified phonological features of a language with a three-way contrast, Hakha Chin. The Laryngeal Realism states that the phonological features are privative and that the aspirating language is specified with the feature [spread glottis], while the true voiced language is specified with the feature of [voice]. It has been widely known that the speech rate affects laryngeal stops asymmetrically, and LR authors argue this is because the phonological features are privative rather than binary (e.g. Kessinger & Blumstein 1997). Methodologically, it attempts to experimentally control the rate variation with the help of metronome (de Jong 2001). The present study observes that in Hakha Chin, at a slower rate, the VOT of the prevoiced stop and the aspirated stop increase, while the voiceless unaspirated does not, which support the claims of the LR, but with caveats due to speaker variations.