Dan Cameron Burgdorf presented a poster titled "Using High-Order Derivatives of Articulatory Trajectories to Identify Gesture Onset" at the 179th Acoustical Society of American Meeting, held virtually Dec 7-11, 2020

Poster Abstract:

Articulatory trajectories are useful for measuring speech properties, but come with complications: a given trajectory may be influenced by multiple articulators and/or multiple overlapping gestures. Standard procedure is to identify landmarks from the trajectory and its velocity.

I present a new procedure: higher order derivatives can be used to identify gesture onsets. High order derivatives are generally associated with signal noise, and therefore not considered to be meaningful. More broadly, however, they reflect the jaggedness or un-smoothness of a signal, which can derive from sources other than random noise.

I demonstrate that such jaggedness at gesture onsets is both predicted by the task dynamic model of speech production (Saltzman & Munhall 1989) and observed in real EMA data. Articulator trajectories generated with the Task Dynamics Application (TADA) Matlab implementation of this model (Nam & Goldstein 2004) show a pattern of increasing activity around changes in gestural activation and decreasing activity elsewhere as successive derivatives are taken.

This was confirmed in EMA data on glides, demonstrating not only that the effect is real, but that it can be measurable above other noise. Activation noise can be isolated with targeted filtering, and may yield new insights into speech motor control.

Rachel Vogel presented a paper titled "Domain Generalization: the case of vowel devoicing in Cheyenne" at the 51st Annual Meeting of the North East Linguistics Society (NELS 51), held Nov 6-8, 2020

Paper Abstract:

Domain generalization has been proposed to account for phonological effects that are phonetically motivated in utterance-final position but appear in other domain-final contexts where they are less well-motivated.[1] In this paper, I examine two processes of vowel devoicing (VD) in Cheyenne (Algonquian, spoken in Montana and Oklahoma),[2] a phrase-level one that is clearly phonetically grounded, and a word-level one that at first glance appears to be somewhat idiosyncratic.

Specifically, I show that while these processes appear on the surface to be quite distinct, they can in fact be unified in terms of domain generalization as the same type of well-motivated edge devoicing phenomenon applying at multiple domains. I further demonstrate that this result is directly predicted within a Stratal OT framework.

Francesco Burroni and Drs. Praneerat Panpraneet and Chutamannee Onuswan (Thammasat University, Bangkok, Thailand) presented a paper titled "Characterizing developmental trajectories in L1 production of Thai tones" at the 45th Boston University Linguistics Conference on Language Development (BUCLD 45), held virtually Nov 5-8, 2020

Paper Abstract:

Recent acoustic work on the topic in Mandarin and Cantonese has shown that L1 tone acquisition is a protracted process in production. In this study, we present further acoustic evidence from Bangkok Thai showing that tones produced by children are distinct from those produced by adults along a variety of perceptually relevant acoustic dimensions.

Some of these differences, like those in F0 measurements, are likely to be the result of anatomical differences. However, other differences, like timing of F0 inflection, early/late acquisition of falling/rising contours, and durational differences are likely to go in tandem with motor control developments.

In our discussion, we focus on asymmetries we have observed in the acquisition of the rising tone shape and its relationship to motor control. We present a dynamical model, rooted in the framework of Articulatory Phonology, that can quantitively simulate differences observed in rising tones produced by adults and children. Moreover, this model also serves as a starting point for a more quantitative discussion of what speech production parameters are refined during the time course of tone acquisition.

Francesco Burroni, Sireemas Maspong, Pimthip Kochaiyaphum, and Pittayawat Pittayaporn presented a paper titled "A new look at Pattani Malay Initial Geminates: A statistical and machine learning approach" at the 34th Pacific Asia Conference on Language, Information and Computation (PACLIC 2020), held virtually October 24-26, 2020.

Francesco and Sireemas' paper was co-authored with Dr. Pittayawat Pittayaporn (a Cornell Phonetics Lab alumnus) and grad student Pimthip Kochaiyaphum - both of Chulalongkorn University, Bangkok, Thailand.   

Paper Abstract:

In this paper, we present a statistical and machine learning approach to the acoustic discrimination of a cross-linguistically unusual phonological contrast, initial geminates vs. singletons in Pattani Malay.

We show that the only statistically significant difference between geminates and singletons is the duration of the consonant itself. No differences in F0 and intensity were observed on the following vowel, contra earlier reports. We further investigated the robustness of this contrast using linear discriminant analysis.

Results show that discrimination is above chance, but poor (~62%). The large overlap between the two categories may be partly due to the naturalistic nature of our speech samples. However, we also found that the contrast is neutralized in some minimal pairs. This merger is surprising since initial geminates are often the sole realization of lexical and morphosyntactic contrasts. We suggest that the singleton/initial geminate contrast is now best characterized as a marginal contrast.

We hypothesize that this marginally contrastive status may be the result of an on-going sound change, perhaps connected with the more modest role that initial geminates play in Pattani Malay morphophonological alternations.