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Spanish voiced stops /b, d, ɡ/ surfaced as fricatives [β, ð, ɣ] in intervocalic position due to a phonological process known as spirantization or, more broadly, lenition. However, conditioned by various factors such as stress, place of articulation, flanking vowel quality, and speaking rate, phonetic studies reveal a great deal of variation and gradience of these surface forms, ranging from fricative-like to approximant-like [β⊤, ð⊤, ɣ⊤]. Several acoustic measurements have been used to quantify the degree of lenition, but none is standard. In this study, the posterior probabilities of sonorant and continuant phonological features in a corpus of Argentinian Spanish estimated by a deep learning Phonet model as measures of lenition were compared to traditional acoustic measurements of intensity, duration, and periodicity. When evaluated against known lenition factors: stress, place of articulation, surrounding vowel quality, word status, and speaking rate, the results show that sonorant and continuant posterior probabilities predict lenition patterns that are similar to those predicted by relative acoustic intensity measures and are in the direction expected by the effort-based view of lenition and previous findings. These results suggest that Phonet is a reliable alternative or additional approach to investigate the degree of lenition.
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An Ultrasound Study of Connemara Irish Palatalization and Velarization
We present the first ultrasound analysis of the secondary palatalization contrast in Irish, analyzing data from five speakers from the Connemara dialect group. Word-initial /pʲ(bʲ),pˠ(bˠ),tʲ,tˠ,kʲ,kˠ,fʲ,fˠ,sʲ,sˠ,xʲ,xˠ/ are analyzed in the context of /iː,uː/. We find, first, that tongue body position robustly distinguishes palatalized from velarized consonants, across place of articulation, manner, and vowel place contexts, with palatalized consonants having fronter and/or higher tongue body realizations than their velarized counterparts. This conclusion holds equally for labial consonants, contrary to some previous descriptive claims. Second, the nature and degree of palatalization and velarization depend in systematic ways on consonant place and manner. In coronal consonants, for example, velarization is weaker or absent. Third, the Irish consonants examined resist coarticulation in backness with a following vowel. In all of these respects Irish palatalization is remarkably similar to that of Russian. Our results also support an independent role for pharyngeal cavity expansion/retraction in the production of the palatalization contrast. Finally, we discuss preliminary findings on the dynamics of the secondary articulation gestures. Our use of principal component analysis (PCA) in reaching these findings is also of interest, since PCA has not been employed a great deal in analyses of tongue body movement.
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- Award ID(s):
- 1423772
- PAR ID:
- 10039005
- Date Published:
- Journal Name:
- Journal of the International Phonetic Association
- ISSN:
- 0025-1003
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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