More Like this

1. Enhancement of intonational contrasts in American English

   Cole, J.; Steffman, J. (September 2023, Proceedings of the International Congress of Phonetic Sciences)

   Skarnitzl, R. (Ed.)

   We test a subset of intonational contrasts proposed in the Autosegmental-Metrical model for American English for evidence of contrast enhancement in phonologically and phonetically longer vs. shorter intervals. F0 trajectories were assessed from 32 speakers’ imitated productions of six tonally distinct tunes, e.g., HHH, HHL. Maximally three tune shapes emerge from clustering analyses of imitated f0 trajectories, each cluster comprising imitations of two phonetically similar but phonologically distinct tunes. We find enhancement of tune contrasts between the emergent clusters in measures of f0 differences (RMSD, end f0, center of gravity). There is no evidence of enhancement for phonetically similar tunes grouped within the same cluster, though fine-grained phonetic distinctions are detected for these “lost” tune contrasts, suggesting a reanalysis as within-category variation. 

   more » « less
2. Hierarchical distinctions in the production and perception of nuclear tunes in American English

   https://doi.org/10.16995/labphon.9437  

   Cole, Jennifer; Steffman, Jeremy; Shattuck-Hufnagel, Stefanie; Tilsen, Sam (January 2023, Laboratory Phonology)

   In Autosegmental-Metrical models of intonational phonology, different types of pitch accents, phrase accents, and boundary tones concatenate to create a set of phonologically distinct phrase-final nuclear tunes. This study asks if an eight-way distinction in nuclear tune shape in American English, predicted from the combination of two (monotonal) pitch accents, two phrase accents, and two boundary tones, is evident in speech production and in speech perception. F0 trajectories from a large-scale imitative speech production experiment were analyzed using bottom-up(k-means) clustering, neural net classification, GAMM modeling, and modeling of turning point alignment. Listeners’ perception of the same tunes is tested in a perceptual discrimination task and related to the imitation results. Emergent grouping of tunes in the clustering analysis, and related classification accuracy from the neural net, show a merging of some of the predicted distinctions among tunes whereby tune shapes that vary primarily in the scaling of final f0 are not reliably distinguished. Within five emergent clusters, subtler distinctions among tunes are evident in GAMMs and f0 turning point modeling. Clustering of individual participants’ production data shows a range of partitions of the data, with nearly all participants making a primary distinction between a class of High-Rising and Non-High-Rising tunes, and with up to four secondary distinctions among the non-Rising class. Perception results show a similar pattern, with poor pairwise discrimination for tunes that differ primarily, but by a small degree, in final f0, and highly accurate discrimination when just one member of a pair is in the High-Rising tune class. Together, the results suggest a hierarchy of distinctiveness among nuclear tunes, with a robust distinction based on holistic tune shape and poorly differentiated distinctions between tunes with the same holistic shape but small differences in final f0. The observed distinctions from clustering, classification, and perception analyses align with the tonal specification of a binary pitch accent contrast {H*, L*} and a maximally ternary {H%, M%, L%} boundary tone contrast; the findings do not support distinct tonal specifications for the phrase accent and boundary tone from the AM model.  

   more » « less
3. Methods for PoLaR Explorations with Machine Learning: Grammatical Analysis of Intonation without Grammatical Labels

   Veilleux, N. (January 2023, International Congress of Phonetic Sciences)

   This study provides a proof-of-concept for a new method for analyzing intonational form and meaning, demonstrated by analysis of mirative utterances in American English. Here, K-means clustering using measures derived from PoLaR labels (i.e., TCoG) revealed emergent clusters of pitch accents that are suggestive of familiar phonological categories (e.g., MAE_ToBI L+H*). A Random Forest analysis then classified utterance-level meaning based on measures from both smaller granularity (related to individual pitch accents) and larger granularity (related to utterance level meaning), showing >85% correct categorization of exclamative vs filler sentences. This work has implications for how to model mappings between prosody and meaning, especially where existing phonological categories alone don’t identify semantic/pragmatic categories. 

   more » « less
4. Paraguayan Guarani: Tritonal Pitch Accent and Accentual Phrase

   Jun, Sun-Ah; Zubizarreta, Maria Luisa (August 2022, International Speech Communication Association (ISCA))

   This paper investigates the intonation system of Paraguayan Guarani in the Autosegmental-metrical (AM) framework of intonational phonology. Previous work on Guarani intonation stated that Guarani has two types of pitch accent, rising (L*+H or LH) and falling (H+L* or HL), and there is no prosodic unit between a word and an Intonational Phrase. But these findings seem to have resulted from the limitation of the data examined. When longer words/sentences and various syntactic structures are examined, it was found that Guarani has one type of pitch accent, a tri-tonal HLH*, and has an Accentual Phrase (AP). The tonal pattern of AP is /H HLH* Ha/, i.e., it has one pitch accent and its edges are marked by a H tone. However, because the pitch accent is tri-tonal, AP edge tones are realized only when an AP is longer than four syllables and stress is not final, suggesting that the function of AP boundary tone is not marking word prominence as in other AP languages. Instead, an important function of Guarani AP seems to mark specific syntactic categories and groupings. These findings are compared with other AP languages and discussed in terms of the typology of word-prominence type. 

   more » « less
5. Paraguayan Guarani: Tritonal Pitch Accent and Accentual Phrase

   Jun, Sun-Ah; Zubizarreta, Maria Luisa (August 2022, Interspeech)

   This paper investigates the intonation system of Paraguayan Guarani in the Autosegmental-metrical (AM) framework of intonational phonology. Previous work on Guarani intonation stated that Guarani has two types of pitch accent, rising (L*+H or LH) and falling (H+L* or HL), and there is no prosodic unit between a word and an Intonational Phrase. But these findings seem to have resulted from the limitation of the data examined. When longer words/sentences and various syntactic structures are examined, it was found that Guarani has one type of pitch accent, a tri-tonal HLH*, and has an Accentual Phrase (AP). The tonal pattern of AP is /H HLH* Ha/, i.e., it has one pitch accent and its edges are marked by a H tone. However, because the pitch accent is tri-tonal, AP edge tones are realized only when an AP is longer than four syllables and stress is not final, suggesting that the function of AP boundary tone is not marking word prominence as in other AP languages. Instead, an important function of Guarani AP seems to mark specific syntactic categories and groupings. These findings are compared with other AP languages and discussed in terms of the typology of word-prominence type. Index Terms: intonation, Paraguayan Guarani, tri-tonal pitch accent, Accentual Phrase, prosodic typology 

   more » « less