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Recent work on rising declaratives proposes a distinction between steep inquisitive rising declaratives and shallow assertive rising declaratives. Yet, it is unclear whether this contrast arises from a phonological distinction of the pitch accent used or a phonetic distinction in the scaling of the boundary tone target. In two perception experiments, we evaluate the contributions of pitch accent and boundary tone in the interpretation of assertive force. In Exp. 1, we find a counterintuitive result for the weighting of pitch accent, which is better understood from the perspective of the Tonal Center of Gravity. This perspective provides a path forward for Exp. 2, which shows no evidence of a contribution from the pitch accent in the interpretation of assertive force. Results speak against a phonological contrast in subtypes of rising declaratives and suggest a need for more narrow investigation in the phonetic domain. 

Unfamiliar native and non-native accents can cause word recognition challenges, particularly in noisy environments, but few studies have incorporated quantitative pronunciation distance metrics to explain intelligibility differences across accents. Here, intelligibility was measured for 18 talkers -- two from each of three native, one bilingual, and five non- native accents -- in three listening conditions (quiet and two noise conditions). Two variations of the Levenshtein pronunciation distance metric, which quantifies phonemic differences from a reference accent, were assessed for their ability to predict intelligibility. An unweighted Levenshtein distance metric was the best intelligibility predictor; talker accent further predicted performance. Accuracy did not fall along a native - non-native divide. Thus, phonemic differences from the listener’s home accent primarily determine intelligibility, but other accent- specific pronunciation features, including suprasegmental characteristics, must be quantified to fully explain intelligibility across talkers and listening conditions. These results have implications for pedagogical practices and speech perception theories. 

According to the influential continuum model of phonation, only voiced segments can be specified as creaky or breathy. The present study investigated many possible phonetic correlates of the laryngeal contrast in Javanese word-initial prevocalic stop consonants, drawing upon a spoken corpus of more than 180,000 utterances. The results indicate that the laryngeal contrast is cued by voice onset time (VOT) and several acoustic-phonetic properties of the following vowel, including the first formant (F1) in addition to voice source measurements such as H1*-H2* and cepstral peak prominence (CPP). Taken together these findings indicate that Javanese stops can be both voiceless and breathy, supporting a revision of the continuum model in which voicing and other aspects of phonation are decoupled. 

Fluid conversation depends on conversation partners’ ability to make predictions about one another’s speech in order to forecast turn ends and prepare upcoming turns. One model used to explain this process of temporal prediction is the coupled oscillator model of turn-taking. A generalization that the model captures is the relative scarcity of interruption in turn-taking, as it predicts partners’ turns should be counter-phased to one another, with minimal pause time between turns. However, in naturalistic conversation, turns are often delayed, rather than occurring in perfect succession. We hypothesize that these delays are not of arbitrary duration, but are structured in their timing, just as between turns with immediate transitions. We demonstrate that relative timing of prosodic events occurring at turn ends is key to modelling pause duration between turns, providing evidence that interturn pauses exist in a temporal trading relation with the final syllable and prosodic word of immediately preceding turn.