• Phonetics 2025 Hong Kong

    Yi Xu

    University College London

    Main areas of research
    Cognitive and computational psychology
    Linguistics
    Neurosciences
    Applied and developmental psychology
    Biological psychology
    Artificial intelligence

    Publications

    Yi Xu is Professor of Speech Sciences at the Department of Speech, Hearing and Phonetic Sciences, Division of Psychology and Language Sciences, University College London. He received his BA degree in English language and literature in 1981 from Shandong University, China, his MA degree in Phonetics in 1984 from Institute of Linguistics, Chinese Academy of Social Sciences, China, and his Ph.D. degree in linguistics in 1993 from the University of Connecticut, USA. He has taught at Northwestern University, USA and University of Chicago, USA. His research covers speech production, speech perception, speech prosody and computational modelling of tone, intonation and speech acquisition.

    How does human language become digital?

    Outline
    It is by now widely recognized that human language is a digital system, and this is what gives language the power to form infinite number of expressions by combining a finite set of discrete units. What is less clear, however, is how language becomes digital. One influential view is that digitization starts from the level of syntax, where discrete lexical items are combined into infinite number of โ€œhierarchically structured expressionsโ€. These expressions are then externalized at the sensorimotor interface and turned into audible speech (Chomsky, 2013). The problem with this view, however, is that it overlooks two basic facts: a) the total number of words is enormously large in any language, and b) words are composed of units that are also discrete, including morphemes, syllables and phonemes.
    In this talk, I will argue that, instead of syntax, phonetics is the level at which language is digitized. That is, instead of being an interface for externalizing a digital syntactic core, phonetics is what makes language digital. I will show that phonetic digitization is done through discretization of consonants, vowels and laryngeal categories in a self-organizing process of interactive articulatory encoding and perceptual decoding. The encoding is enabled by the syllable, an articulatory mechanism that synchronizes the onsets of consonantal, vocalic and laryngeal gestures. The perceptual decoding is done by direct processing of the acoustic signal of each phonetic category without separately extracting abstract cues. Both production and perception skills are acquired through learning, a process that resolves variability arising from coarticulation, speaker differences and multi-functional interactions. Of the two, however, perceptual learning is much easier, as it requires no prior knowledge of articulation. Production learning, in contrast, relies on the guidance of perception. The digitization of language is therefore realized by maximizing the production-perception consistency only at the level of contrastive phonetic categories.
    In summary, it is the discretization of the phonetic categories that creates the basic digits of language that can be combined, often recursively, to form morphemes, words, phrases and sentences that make up the hierarchical structure of all human languages.

  • Phonetics 2025 Hong Kong

    Janet Fletcher

    The University of Melbourne

    Main areas of research
    Phonetics theory, prosodic phonology, laboratory phonology, and articulatory and acoustic modelling of prosodic effects in various languages, particularly indigenous Australian languages and French.

    Publications

    Janet Fletcher is Professor of Phonetics in the School of Languages and Linguistics. She has held previous appointments at the University of Edinburgh, the Ohio State University, and Macquarie University. Her research interests include phonetic theory, laboratory phonology, prosodic phonology, articulatory and acoustic modelling of prosodic effects in various languages. She is currently working on phonetic variation in French Polynesian languages, and has worked extensively on coarticulation, prosody, and intonation in Indigenous Australian languages. She is a member of the Research Unit for Indigenous Language in the School of Languages and Linguistics and an elected Fellow to the Australian Academy of Humanities.

    Exploring the phonetics and phoology of Tahitian

    Outline
    In the last ten years or more, we have seen expanded interest in quantitative phonetic analyses and documentation of under-resourced languages of the Pacific. In this talk I will present recent work on the Eastern Polynesian language, Tahitian. The Eastern Polynesian languages, including Hawaiian, Tahitian, and Marquesan (North and South) are often described as having extremely simple phonological properties.  They have relatively few consonant contrasts and have simple syllable phonotactics compared to many well-resourced languages like English. Tahitian is also claimed to have a predictable lexical stress system, however this has never been fully investigated experimentally. Nor has the consonant or vowel system or  intonational phonology of the language been analysed fully.   I will argue that  the phonetic exploration of so-called simple languages can contribute to various aspects of phonetic and phonological typology. Results of recent experimental investigations of Tahitian accentual prominence  and stop consonant variation will be presented.  I will  also focus on glottal stop variation in light of recent research on a close-related neighbouring language, Hawaiian, and cross-linguistic surveys of glottal articulations (e.g. Davidson 2021, Davidson and Parker-Jones 2023, Garellek et al 2021, Keating et al. 2023).  It is well accepted that in many languages, phonemic /ส”/ has multiple variants. Glottalization can also signal higher level prosodic boundaries for example and Tahitian presents no exception in this regard. 
     Our studies to date have shown that previous impressionistic descriptions of accentual prominence are more or less confirmed with Tahitian behaving like a classic โ€œhead prominenceโ€ language with  late-rising or early-rising post-lexical pitch prominences docking on to phonologically stressed syllables, and there are key tonal alignment differences depending on whether the vowel is phonologically long or short.  Accentually prominent syllables are also longer and louder than unstressed syllables although the effect is clearest in long vowels. 
    Close inspection of the consonant system also shows that similar to many other languages of the world with contrastive glottal stops, Tahitian has glottal variants ranging from a fully or partially-occluded โ€œcanonicalโ€ glottal stop to creaky voiced, breathy, and  modal voiced allophones. However, compared to the closely-related Eastern Polynesian language Hawaiian, the proportion of canonical glottal stops is somewhat higher at 68% compared with 7%  (Fletcher and Gregory 2024, Davidson 2021). In general, glottal stops in Tahitian tend to be more โ€œconsonantalโ€ rather than โ€œvocalicโ€. Moreover, as one would expect there is also stress-conditioned vowel glottalization in the vicinity of phonemic glottal stops. The data clearly show evidence of  glottal coarticulation in either direction, with many standard acoustic parameters of voice quality including spectral tilt and harmonics-to-noise ratio (HNR) signaling more vowel glottalization in unstressed versus stressed syllables suggesting localized hyperarticulation due to prosodic prominence. Languages with so-called โ€œsimpleโ€ phonetics and phonology like Tahitian show similar patterns of phonetic variation to those with far more complex phonetic and phonological structures and are therefore worthy of experimental investigation.

  • Phonetics 2025 Hong Kong

    Niels Schiller

    City University of Hong Kong

    Main areas of research
    Psycholinguistics
    Neurolinguistics
    Speech Production
    Morphological and phonological encoding
    Representation of lexico-syntactic features
    Multilingualism

    Publications

    Niels O. Schiller is a Chair Professor of Psycho- and Neurolinguistics at City University of Hong Kong and Head of Department of Linguistics and Translation. After his undergraduate studies at Trier University in Germany, Schiller was awarded a scholarship from the German Max Planck Society to carry out his PhD research at the Max Planck Institute for Psycholinguistics in Nijmegen, The Netherlands. In 1997, he received his PhD in Psychology from the Radboud University in Nijmegen. In his PhD dissertation, Schiller investigated the role of the syllable in lexical access during speech production. Following his PhD, he held research positions at Harvard University, Maastricht University and the Max Planck Institute for Psycholinguistics. In 2004, Schiller was appointed professor of psycholinguistics at Maastricht University, and in 2006 he became professor of psycho- and neurolinguistics at Leiden University, before moving to Hong Kong in 2024. Schillerโ€™s research interests include lexico-syntactic, morphological, and phonological encoding processes in mono- and multilingual language production.

    From thought to sound in speech production

    Outline
    Speaking is one of the most complex human skills. Producing speech is an extremely fast process that includes lots of planning ahead. Nevertheless, it is very robust and in informal speech we only make about one speech error in thousand words. In my talk, I will describe the cognitive processes that take place during speaking, from conceptualisation, via lexical access and lexical selection, to word form encoding and articulation. I will illustrate each process by experimental work. 
    I will especially zoom into word selection from the mental lexicon and the representation and processing of lexico-syntactic features, such as grammatical gender in Indo-European languages but also classifiers in Mandarin Chinese. I will also present data from L2 learners of grammatical gender and classifier systems.
    Furthermore, I will present data on word-form encoding, especially morphological encoding (compounding) and phonological encoding (syllables). These data have been acquired with several distinct methodologies (behavioural, electrophysiological, neuroimaging) and from distinct populations (neurotypical participants and patients).
    I will conclude by arguing that the combination of different research methodologies, populations, and languages will lead a more comprehensive insights into speech processing.