TY - JOUR A1 - Gafos, Adamantios I. A1 - Lieshout, Pascal H. H. M. van T1 - Models and theories of speech production BT - editorial JF - Frontiers in psychology KW - speech production KW - motor control KW - dynamical models KW - phonology KW - speech KW - disorders KW - timing Y1 - 2020 U6 - https://doi.org/10.3389/fpsyg.2020.01238 SN - 1664-1078 VL - 11 PB - Frontiers Research Foundation CY - Lausanne ER - TY - JOUR A1 - Ghaffarvand-Mokari, Payam A1 - Gafos, Adamantios I. A1 - Williams, Daniel T1 - Perceptuomotor compatibility effects in vowels BT - beyond phonemic identity JF - Attention, perception, & psychophysics N2 - Perceptuomotor compatibility between phonemically identical spoken and perceived syllables has been found to speed up response times (RTs) in speech production tasks. However, research on compatibility effects between perceived and produced stimuli at the subphonemic level is limited. Using a cue-distractor task, we investigated the effects of phonemic and subphonemic congruency in pairs of vowels. On each trial, a visual cue prompted individuals to produce a response vowel, and after the visual cue appeared a distractor vowel was auditorily presented while speakers were planning to produce the response vowel. The results revealed effects on RTs due to phonemic congruency (same vs. different vowels) between the response and distractor vowels, which resemble effects previously seen for consonants. Beyond phonemic congruency, we assessed how RTs are modulated as a function of the degree of subphonemic similarity between the response and distractor vowels. Higher similarity between the response and distractor in terms of phonological distance-defined by number of mismatching phonological features-resulted in faster RTs. However, the exact patterns of RTs varied across response-distractor vowel pairs. We discuss how different assumptions about phonological feature representations may account for the different patterns observed in RTs across response-distractor pairs. Our findings on the effects of perceived stimuli on produced speech at a more detailed level of representation than phonemic identity necessitate a more direct and specific formulation of the perception-production link. Additionally, these results extend previously reported perceptuomotor interactions mainly involving consonants to vowels. KW - speech perception KW - speech production KW - psycholinguistics Y1 - 2020 U6 - https://doi.org/10.3758/s13414-020-02014-1 SN - 1943-3921 SN - 1943-393X VL - 82 IS - 5 SP - 2751 EP - 2764 PB - Springer CY - New York ER - TY - GEN A1 - Shaw, Jason A. A1 - Gafos, Adamantios I. T1 - Stochastic time models of syllable structure T2 - Postprints der Universität Potsdam : Humanwissenschaftliche Reihe N2 - Drawing on phonology research within the generative linguistics tradition, stochastic methods, and notions from complex systems, we develop a modelling paradigm linking phonological structure, expressed in terms of syllables, to speech movement data acquired with 3D electromagnetic articulography and X-ray microbeam methods. The essential variable in the models is syllable structure. When mapped to discrete coordination topologies, syllabic organization imposes systematic patterns of variability on the temporal dynamics of speech articulation. We simulated these dynamics under different syllabic parses and evaluated simulations against experimental data from Arabic and English, two languages claimed to parse similar strings of segments into different syllabic structures. Model simulations replicated several key experimental results, including the fallibility of past phonetic heuristics for syllable structure, and exposed the range of conditions under which such heuristics remain valid. More importantly, the modelling approach consistently diagnosed syllable structure proving resilient to multiple sources of variability in experimental data including measurement variability, speaker variability, and contextual variability. Prospects for extensions of our modelling paradigm to acoustic data are also discussed. T3 - Zweitveröffentlichungen der Universität Potsdam : Humanwissenschaftliche Reihe - 514 KW - speech production KW - temporal organization KW - complex onsets KW - english KW - cues KW - perception KW - syllabication KW - articulation KW - categories KW - phonology Y1 - 2019 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-409815 SN - 1866-8364 IS - 514 ER - TY - GEN A1 - Hullebus, Marc Antony A1 - Tobin, Stephen J. A1 - Gafos, Adamantios I. T1 - Speaker-specific structure in German voiceless stop voice onset times T2 - 19th Annual confernce of the international speech communication association (INTERSPEECH 2018), VOLS 1-6: speech research for emerging markets in multilingual societies N2 - Voice onset time (VOT), a primary cue for voicing in many languages including English and German, is known to vary greatly between speakers, but also displays robust within-speaker consistencies, at least in English. The current analysis extends these findings to German. VOT measures were investigated from voiceless alveolar and velar stops in CV syllables cued by a visual prompt in a cue-distractor task. Comparably to English, a considerable portion of German VOT variability can be attributed to the syllable’s vowel length and the stop’s place of articulation. Individual differences in VOT still remain irrespective of speech rate. However, significant correlations across places of articulation and between speaker-specific mean VOTs and standard deviations indicate that talkers employ a relatively unified VOT profile across places of articulation. This could allow listeners to more efficiently adapt to speaker-specific realisations. KW - speech production KW - speech variability KW - voice onset time Y1 - 2018 SN - 978-1-5108-7221-9 U6 - https://doi.org/10.21437/Interspeech.2018-2288 SN - 2308-457X SP - 1403 EP - 1407 PB - ISCA-International Speech Communication Association CY - Baixas ER -