The effect of contrast-specific minimal pair competitor in hyperarticulation of VOT and F0 phonetic cues in Korean initial stops in tonogenetic sound change

In Seoul Korean, VOT is historically a primary cue distinguishing the aspirated(Formula presented) lenis contrast in stops, with fundamental frequency (F0) of the following vowel as a secondary cue. However, for many speakers a transphonologization is in progress in which the VOT cue progresses toward neutralization, with a concomitant expansion of the F0 contrast. Prior research shows that phonetic cues which distinguish a lexical minimal pair are hyperarticulated, and suggests that this contrastive hyperarticulation influences the trajectory of change in that phoneme contrast. Here we investigate minimal pair-associated hyperarticulaton of the VOT and F0 contrasts of aspirated/lenis stops in both a production study and a study of a corpus of natural speech. We ask (i) if we in fact find contrastive hyperarticulation of the aspirated(Formula presented) lenis distinction in minimal pairs, and (ii) if the degree of VOT hyperarticulation tracks the degree to which a speaker employs the VOT cue in the aspirated(Formula presented) lenis distinction. We find that speakers contrastively hyperarticulate both the VOT and F0 cues to the aspirated(Formula presented) lenis distinction, although hyperarticulation of the F0 contrast is less robust. Moreover, using a new measure of advancement in this sound change, we show that VOT still shows minimal pair-associated hyperarticulation even in advanced speakers who do not detectably use VOT in their general speech. We discuss possible explanations for why minimal pair-associated hyperarticulation of VOT appears to persist in these advanced speakers, and its implications for theories of sound change.