The phonetic realization of phonologically related speech sounds is
in its variability:
attributes of the acoustic signal involved in producing phonological features are often mutually predictable across a series of speech sounds having the same valuation of that feature.
I have investigated this aspect of phonetic structure mainly through the phonetic implementation of vowel systems, through ultrasound studies of vowel production in Suzhou Chinese and L2 French spoken by American English learners.
on Suzhou Chinese fricative vowels (see below), begun during my dissertation, points to a constraint on the activity of articulators rather than acoustics.
Fricative vowels / 摩擦化元音
Fricative vowels are understudied segments which occur in most varieties of Chinese, as well as a handful of languages elsewhere (Swedish, Grassfields Bantu). Their phonetic implementation involves a constriction resembling a fricative consonant at a coronal or labial place of articulation which
results in light fricative noise.
In spite of their consonant-like articulation, fricative vowels are
in their phonological patterning. They are thus an informative "edge case" for phonological feature theory, especially as it relates to vowels, continuant consonants, and the division between them.
I have investigated the articulatory and acoustic properties of fricative vowels and the so-called apical vowels (舌尖元音) in
and Southern Mandarin varieties of Chinese, as well as in languages of Cameroon, including the
Kejom and Kom.
As part of this program I have collected phonetic data from the field in both Cameroon and China, including my dissertation data.
Covert variation and systematicity
Not all articulatory variability is readily detectable in acoustic output. Speakers nonetheless may deploy covertly different articulatory variants in systematic but often idiosyncratic ways. This speaker-internal systematicity is well known from the study of North American English /ɹ/, which has a continuum of relatively bunched and retroflex variants indistinguishable to listeners, but which are nonetheless retroflexed or bunched in certain environments according to speaker-specific grammars.
Description of these grammars may offer an opportunity to probe the nature of phonological and phonetic representations, and to characterize the boundaries of grammatical variation.
Ongoing work as part of a group project at UCLA aims to expand on descriptions of the distribution of the four covertly different variants for the flap/tap [ɾ] in North American English, which are conditioned mainly by the lingual activity targets for surrounding segments and planning for other upcoming flaps. We have observed that speakers vary in whether they are sensitive to the context before or after the flap (or both),
suggesting interspeaker variation in representation of action
or in motor planning.
Liu, S., and Sundara, M.
Nasal coda neutralization in Shanghai Mandarin: Articulatory and perceptual evidence.
Uniform articulatory implementation and the Suzhou Chinese fricative vowels.
High vowel fricativization in Northern Wu Chinese and its neighbors.
In Enke, D., Weber, T., Hyman, L., Nichols, J., and Seiler, G. (eds.),
Language Change for the Worse.
and Akumbu, P.
Kejom (Babanki). Illustration of the IPA.
Journal of the IPA. [preprint]
Lionnet, F., and
Areal patterns in the vowel systems of the Macro-Sudan Belt.
Linguistic Typology 24(1).
In edited volumes
Sonority in some languages of the Cameroon Grassfields.
In Challenging Sonority, Martin J. Ball and Nicole Müller eds.,
Refereed conference papers
Kuo, J., and Wang, S.
Lingual articulation of the Sūzhōu Chinese labial fricative vowels.
ICPhS 19, Melbourne.
and Nara, K.
Manner differences in the Punjabi dental-retroflex contrast: an ultrasound study of time-series data.
ICPhS 19, Melbourne.
and Lin, S.
Articulatory variability and fricative noise in Standard Mandarin apical vowels.
ICPhS 18, Glasgow.
Selected conference presentations
Articulatory, but not acoustic, target uniformity in Suzhou Chinese. LSA 94, New Orleans.
Liu, S. and Faytak, M.
Articulation and perception of Mandarin coda nasals by Shanghainese-Mandarin bilinguals. LSA 94, New Orleans.
Aziz, J., Barnett, P., Jo, J., Kuo, J., Teixeira, G., Wu, J., Zhou, Z., and Keating, P.
Flap articulation and lowered fourth formant.
ASA 178, San Diego.
Faytak, M. (2019).
Uniformity constrains innovative variants of the Suzhou Chinese fricative vowels.
5th Workshop on Sound Change, Davis.
Faytak, M. and Akumbu, A. (2019).
Vowel assimilation to onset place in Kejom.
ACAL 50, University of British Columbia.
and Johnson, K.
Evaluating a new measure of fricative source intensity.
LabPhon 15, Cornell.
High vowel fricativization as an areal feature of the northern Cameroon Grassfields.
WOCAL 8, Kyoto.