TY  - JOUR
A1  - Roon, Kevin D.
A1  - Gafos, Adamantios I.
T1  - Perceiving while producing: Modeling the dynamics of phonological planning
JF  - Journal of memory and language
N2  - We offer a dynamical model of phonological planning that provides a formal instantiation of how the speech production and perception systems interact during online processing. The model is developed on the basis of evidence from an experimental task that requires concurrent use of both systems, the so-called response-distractor task in which speakers hear distractor syllables while they are preparing to produce required responses. The model formalizes how ongoing response planning is affected by perception and accounts for a range of results reported across previous studies. It does so by explicitly addressing the setting of parameter values in representations. The key unit of the model is that of the dynamic field, a distribution of activation over the range of values associated with each representational parameter. The setting of parameter values takes place by the attainment of a stable distribution of activation over the entire field, stable in the sense that it persists even after the response cue in the above experiments has been removed. This and other properties of representations that have been taken as axiomatic in previous work are derived by the dynamics of the proposed model. (C) 2016 Elsevier Inc. All rights reserved.
KW  - Speech perception
KW  - Speech production
KW  - Computational modeling
KW  - Response time modulation
KW  - Phonological planning
Y1  - 2016
U6  - https://doi.org/10.1016/j.jml.2016.01.005
SN  - 0749-596X
SN  - 1096-0821
VL  - 89
SP  - 222
EP  - 243
PB  - Elsevier
CY  - San Diego
ER  - 
TY  - JOUR
A1  - Sorensen, Tanner
A1  - Gafos, Adamantios I.
T1  - The Gesture as an Autonomous Nonlinear Dynamical System
JF  - Ecological psychology : a publication of the International Society for Ecological Psychology
N2  - We propose a theory of how the speech gesture determines change in a functionally relevant variable of vocal tract state (e.g., constriction degree). A core postulate of the theory is that the gesture determines how the variable evolves in time independent of any executive timekeeper. That is, the theory involves intrinsic timing of speech gestures. We compare the theory against others in which an executive timekeeper determines change in vocal tract state. Theories that employ an executive timekeeper have been proposed to correct for disparities between theoretically predicted and experimentally observed velocity profiles. Such theories of extrinsic timing make the gesture a nonautonomous dynamical system. For a nonautonomous dynamical system, the change in state depends not just on the state but also on time. We show that this nonautonomous extension makes surprisingly weak kinematic predictions both qualitatively and quantitatively. We propose instead that the gesture is a theoretically simpler nonlinear autonomous dynamical system. For the proposed nonlinear autonomous dynamical system, the change in state depends nonlinearly on the state and does not depend on time. This new theory provides formal expression to the notion of intrinsic timing. Furthermore, it predicts experimentally observed relations among kinematic variables.
Y1  - 2016
U6  - https://doi.org/10.1080/10407413.2016.1230368
SN  - 1040-7413
SN  - 1532-6969
VL  - 28
SP  - 188
EP  - 215
PB  - Elsevier
CY  - Abingdon
ER  - 
TY  - JOUR
A1  - Gibson, Mark
A1  - Sotiropoulou, Stavroula
A1  - Tobin, Stephen
A1  - Gafos, Adamantios I.
T1  - Temporal Aspects of Word Initial Single Consonants and Consonants in Clusters in Spanish
JF  - Phonetic
N2  - We examined gestural coordination in C1C2 (C1 stop, C2 lateral or tap) word initial clusters using articulatory (electromagnetic articulometry) and acoustic data from six speakers of Standard Peninsular Spanish. We report on patterns of voice onset time (VOT), gestural plateau duration of C1, C2, and their overlap. For VOT, as expected, place of articulation is a major factor, with velars exhibiting longer VOTs than labials. Regarding C1 plateau duration, voice and place effects were found such that voiced consonants are significantly shorter than voiceless consonants, and velars show longer duration than labials. For C2 plateau duration, lateral duration was found to vary as a function of onset complexity (C vs. CC). As for overlap, unlike in French, where articulatory data for clusters have also been examined, clusters where both C1 and C2 are voiced show more overlap than where voicing differs. Further, overlap was affected by the C2 such that clusters where C2 is a tap show less overlap than clusters where C2 is a lateral. We discuss these results in the context of work aiming to uncover phonetic (e.g., articulatory or perceptual) and phonological forces (e.g., syllabic organization) on timing.
Y1  - 2019
U6  - https://doi.org/10.1159/000501508
SN  - 0031-8388
SN  - 1423-0321
VL  - 76
IS  - 6
SP  - 448
EP  - 478
PB  - Karger
CY  - Basel
ER  - 
TY  - JOUR
A1  - Tobin, Stephen
A1  - Hullebus, Marc Antony
A1  - Gafos, Adamantios I.
T1  - Immediate phonetic convergence in a cue-distractor paradigm
JF  - The journal of the Acoustical Society of America
N2  - During a cue-distractor task, participants repeatedly produce syllables prompted by visual cues. Distractor syllables are presented to participants via headphones 150 ms after the visual cue (before any response). The task has been used to demonstrate perceptuomotor integration effects (perception effects on production): response times (RTs) speed up as the distractor shares more phonetic properties with the response. Here it is demonstrated that perceptuomotor integration is not limited to RTs. Voice Onset Times (VOTs) of the distractor syllables were systematically varied and their impact on responses was measured. Results demonstrate trial-specific convergence of response syllables to VOT values of distractor syllables.
Y1  - 2018
U6  - https://doi.org/10.1121/1.5082984
SN  - 0001-4966
SN  - 1520-8524
VL  - 144
IS  - 6
SP  - EL528
EP  - EL534
PB  - American Institute of Physics
CY  - Melville
ER  - 
TY  - JOUR
A1  - Tamasi, Katalin
A1  - Mckean, Cristina
A1  - Gafos, Adamantios I.
A1  - Höhle, Barbara
T1  - Children's gradient sensitivity to phonological mismatch
BT  - Considering the dynamics of looking behavior and pupil dilation
JF  - Journal of child language
N2  - In a preferential looking paradigm, we studied how children's looking behavior and pupillary response were modulated by the degree of phonological mismatch between the correct label of a target referent and its manipulated form. We manipulated degree of mismatch by introducing one or more featural changes to the target label. Both looking behavior and pupillary response were sensitive to degree of mismatch, corroborating previous studies that found differential responses in one or the other measure. Using time-course analyses, we present for the first time results demonstrating full separability among conditions (detecting difference not only between one vs. more, but also between two and three featural changes). Furthermore, the correct labels and small featural changes were associated with stable target preference, while large featural changes were associated with oscillating looking behavior, suggesting significant shifts in looking preference over time. These findings further support and extend the notion that early words are represented in great detail, containing subphonemic information.
KW  - lexical development
KW  - featural distance
KW  - mispronunciation detection
KW  - eye-tracking
KW  - pupillometry
Y1  - 2018
U6  - https://doi.org/10.1017/S0305000918000259
SN  - 0305-0009
SN  - 1469-7602
VL  - 46
IS  - 1
SP  - 1
EP  - 23
PB  - Cambridge Univ. Press
CY  - New York
ER  - 
TY  - JOUR
A1  - Williams, Daniel Philip
A1  - Escudero, Paola
A1  - Gafos, Adamantios I.
T1  - Spectral change and duration as cues in Australian English listeners' front vowel categorization
JF  - The journal of the Acoustical Society of America
N2  - Australian English /iː/, /ɪ/, and /ɪə/ exhibit almost identical average first (F1) and second (F2) formant frequencies and differ in duration and vowel inherent spectral change (VISC). The cues of duration, F1 × F2 trajectory direction (TD) and trajectory length (TL) were assessed in listeners' categorization of /iː/ and /ɪə/ compared to /ɪ/. Duration was important for distinguishing both /iː/ and /ɪə/ from /ɪ/. TD and TL were important for categorizing /iː/ versus /ɪ/, whereas only TL was important for /ɪə/ versus /ɪ/. Finally, listeners' use of duration and VISC was not mutually affected for either vowel compared to /ɪ/.
Y1  - 2018
U6  - https://doi.org/10.1121/1.5055019
SN  - 0001-4966
SN  - 1520-8524
VL  - 144
IS  - 3
SP  - EL215
EP  - EL221
PB  - American Institute of Physics
CY  - Melville
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  - Brunner, Jana
A1  - Geng, Christian
A1  - Sotiropoulou, Stavroula
A1  - Gafos, Adamantios I.
T1  - Timing of German onset and word boundary clusters
T2  - Postprints der Universität Potsdam : Philosophische Reihe
N2  - Previous studies suggest that there are special timing relations in syllable onsets. The consonants are assumed to be timed, on the one hand, with the vocalic nucleus and, on the other hand, with each other. These competing timing relations result in the C-center effect. However, the C-center effect has not consistently been found in languages with complex onsets. Moreover, it has occasionally been found in languages disallowing complex onsets. The present study investigates onset timing in German while discussing alternative explanations (not related to bonding) for the timing patterns observed. Six German speakers were recorded via Electromagnetic Articulography. The corpus contained items with four clusters (/sk/, /kv/, /gl/, and /pl/). The clusters occur in word-initial position, word-medial position, and across a word boundary preceding different vowels. The results suggest that segmental properties (i.e., oral-laryngeal coordination, coarticulatory resistance) determine the observed timing patterns, and specifically the absence or presence of the C-center effect.
T3  - Zweitveröffentlichungen der Universität Potsdam : Philosophische Reihe - 136 
KW  - C-center
KW  - gestural coordination
KW  - coarticulatory resistance
Y1  - 2017
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-399178
SN  - 1866-8380
IS  - 136
ER  - 
TY  - GEN
A1  - Shaw, Jason A.
A1  - Gafos, Adamantios I.
A1  - Hoole, Philip
A1  - Zeroual, Chakir
T1  - Dynamic invariance in the phonetic expression of syllable structure
BT  - a case study of Moroccan Arabic consonant clusters
T2  - Postprints der Universität Potsdam : Humanwissenschaftliche Reihe
N2  - We asked whether invariant phonetic indices for syllable structure can be identified in a language where word-initial consonant clusters, regardless of their sonority profile, are claimed to be parsed heterosyllabically. Four speakers of Moroccan Arabic were recorded, using Electromagnetic Articulography. Pursuing previous work, we employed temporal diagnostics for syllable structure, consisting of static correspondences between any given phonological organisation and its presumed phonetic indices. We show that such correspondences offer only a partial understanding of the relation between syllabic organisation and continuous indices of that organisation. We analyse the failure of the diagnostics and put forth a new approach in which different phonological organisations prescribe different ways in which phonetic indices change as phonetic parameters are scaled. The main finding is that invariance is found in these patterns of change, rather than in static correspondences between phonological constructs and fixed values for their phonetic indices.
T3  - Zweitveröffentlichungen der Universität Potsdam : Humanwissenschaftliche Reihe - 516 
KW  - american english
KW  - perception
KW  - speech
KW  - organization
KW  - duration
KW  - patterns
KW  - syllabication
KW  - articulation
KW  - sequences
KW  - knowledge
Y1  - 2019
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-412479
SN  - 1866-8364
IS  - 516
SP  - 455
EP  - 490
ER  - 
TY  - JOUR
A1  - Gafos, Adamantios I.
T1  - Multistability in speech and other activities
JF  - Of trees and birds. A Festschrift for Gisbert Fanselow
KW  - Festschrift
KW  - Informationsstruktur
KW  - Linguistik
KW  - Morphologie
KW  - Syntax
KW  - festschrift
KW  - information structure
KW  - linguistics
KW  - morphology
KW  - syntax
Y1  - 2019
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-432580
SN  - 978-3-86956-457-9
SP  - 343
EP  - 360
PB  - Universitätsverlag Potsdam
CY  - Potsdam
ER  - 
TY  - BOOK
A1  - Olsen, Susan
A1  - Stiebels, Barbara
A1  - Bierwisch, Manfred
A1  - Zimmermann, Ilse
A1  - Cavar, Damir
A1  - Georgi, Doreen
A1  - Bacskai-Atkari, Julia
A1  - Alexiadou, Artemis
A1  - Błaszczak, Joanna
A1  - Müller, Gereon
A1  - Šimík, Radek
A1  - Meinunger, André
A1  - Thiersch, Craig
A1  - Arnhold, Anja
A1  - Féry, Caroline
A1  - Bayer, Josef
A1  - Titov, Elena
A1  - Fominyam, Henry
A1  - Tran, Thuan
A1  - Bornkessel-Schlesewsky, Ina D.
A1  - Schlesewsky, Matthias
A1  - Zimmermann, Malte
A1  - Häussler, Jana
A1  - Mucha, Anne
A1  - Schmidt, Andreas
A1  - Weskott, Thomas
A1  - Wierzba, Marta
A1  - Stede, Manfred
A1  - Skopeteas, Stavros
A1  - Gafos, Adamantios I.
A1  - Haider, Hubert
A1  - Wunderlich, Dieter
A1  - Staudacher, Peter
A1  - Rauh, Gisa
ED  - Brown, Jessica M. M.
ED  - Schmidt, Andreas
ED  - Wierzba, Marta
T1  - Of Trees and Birds
BT  - A Festschrift for Gisbert Fanselow
N2  - Gisbert Fanselow’s work has been invaluable and inspiring to many ­researchers working on syntax, morphology, and information ­structure, both from a ­theoretical and from an experimental perspective. This ­volume comprises a collection of articles dedicated to Gisbert on the occasion of his 60th birthday, covering a range of topics from these areas and beyond. The contributions have in ­common that in a broad sense they have to do with language structures (and thus trees), and that in a more specific sense they have to do with birds. They thus cover two of Gisbert’s major interests in- and outside of the linguistic world (and ­perhaps even at the interface).
KW  - Festschrift
KW  - Linguistik
KW  - Syntax
KW  - Morphologie
KW  - Informationsstruktur
KW  - festschrift
KW  - linguistics
KW  - syntax
KW  - morphology
KW  - information structure
Y1  - 2019
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-426542
SN  - 978-3-86956-457-9
PB  - Universitätsverlag Potsdam
CY  - Potsdam
ER  - 
TY  - JOUR
A1  - Shaw, Jason A.
A1  - Gafos, Adamantios I.
T1  - Stochastic Time Models of Syllable Structure
JF  - PLoS one
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.
Y1  - 2015
U6  - https://doi.org/10.1371/journal.pone.0124714
SN  - 1932-6203
VL  - 10
IS  - 5
PB  - PLoS
CY  - San Fransisco
ER  - 
TY  - JOUR
A1  - Gafos, Adamantios I.
A1  - Charlow, Simon
A1  - Shaw, Jason A.
A1  - Hoole, Philip
T1  - Stochastic time analysis of syllable-referential intervals and simplex onsets
JF  - Journal of phonetics
N2  - We pursue an analysis of the relation between qualitative syllable parses and their quantitative phonetic consequences. To do this, we express the statistics of a symbolic organization corresponding to a syllable parse in terms of continuous phonetic parameters which quantify the timing of the consonants and vowels that make up syllables: consonantal plateau durations, vowel durations, and their variances. These parameters can be estimated from continuous phonetic data. This enables analysis of the link between symbolic phonological form and the continuous phonetics in which this form is manifest. Pursuing such an analysis, we illustrate the predictions of the syllabic organization corresponding to simplex onsets and derive a number of previously experimentally observed and simulation results. Specifically, we derive not only the canonical phonetic manifestations of simplex onsets but also the result that, under certain conditions we make precise, the phonetic indices of the simplex onset organization change to a range of values characteristic of the complex onset organization. Finally, we explore the behavior of phonetic indices for syllabic organization over progressively increasing,sizes of lexical samples, thereby concomitantly diversifying the phonetic context over which these indices are taken.
Y1  - 2014
U6  - https://doi.org/10.1016/j.wocn.2013.11.007
SN  - 0095-4470
VL  - 44
SP  - 152
EP  - 166
PB  - Elsevier
CY  - London
ER  - 
TY  - JOUR
A1  - Roon, Kevin D.
A1  - Gafos, Adamantios I.
T1  - Perceptuo-motor effects of response-distractor compatibility in speech: beyond phonemic identity
JF  - Psychonomic bulletin & review : a journal of the Psychonomic Society
N2  - Previous studies have found faster response times in a production task when a speaker perceives a distractor syllable that is identical to the syllable they are required to produce. No study has found such effects when a response and a distractor are not identical but share parameters below the level of the phoneme. Results from Experiment 1 show some evidence of a response-time effect of response-distractor voicing congruency. Experiment 2 showed a robust effect of articulator congruency: perceiving a distractor that has the same articulatory organ as that implicated in the planned motor response speeds up response times. These results necessitate a more direct and specific formulation of the perception-production link than warranted by previous experimental evidence. Implications for theories of speech production are also discussed.
KW  - Speech perception
KW  - Speech production
KW  - Motor planning/programming
KW  - Psycholinguistics
Y1  - 2015
U6  - https://doi.org/10.3758/s13423-014-0666-6
SN  - 1069-9384
SN  - 1531-5320
VL  - 22
IS  - 1
SP  - 242
EP  - 250
PB  - Springer
CY  - New York
ER  - 
TY  - GEN
A1  - Williams, Daniel
A1  - Escudero, Paola
A1  - Gafos, Adamantios I.
T1  - Perceptual sensitivity to spectral change in Australian English close front vowels
BT  - an electroencephalographic investigation
T2  - 19 th annual conference of the international speech communicaton association (INTERSPEECH 2018), VOLS 1-6: Speech research for emerging marjets in multilingual societies
N2  - Speech scientists have long noted that the qualities of naturally-produced vowels do not remain constant over their durations regardless of being nominally "monophthongs" or "diphthongs". Recent acoustic corpora show that there are consistent patterns of first (F1) and second (F2) formant frequency change across different vowel categories. The three Australian English (AusE) close front vowels /i:, 1, i/ provide a striking example: while their midpoint or mean F1 and F2 frequencies are virtually identical, their spectral change patterns distinctly differ. The results indicate that, despite the distinct patterns of spectral change of AusE /i:, i, la/ in production, its perceptual relevance is not uniform, but rather vowel-category dependent.
KW  - vowels
KW  - pre-attentive discrimination
KW  - speech perception
KW  - speech acoustics
KW  - English dialects
Y1  - 2018
SN  - 978-1-5108-7221-9
U6  - https://doi.org/10.21437/Interspeech.2018-2505
SN  - 2308-457X
SP  - 1442
EP  - 1446
PB  - ISCA-International Speech Communication Association
CY  - Baixas
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  - 
TY  - JOUR
A1  - Höhle, Barbara
A1  - Fritzsche, Tom
A1  - Boll-Avetisyan, Natalie
A1  - Hullebus, Marc
A1  - Gafos, Adamantios I.
T1  - Respect the surroundings
BT  - effects of phonetic context variability on infants' learning of minimal pairs
JF  - JASA Express Letters
N2  - Fourteen-month-olds' ability to distinguish a just learned word, /bu?k/, from its minimally different word, /du?k/, was assessed under two pre-exposure conditions: one where /b, d/-initial forms occurred in a varying vowel context and another where the vowel was fixed but the final consonant varied. Infants in the experiments benefited from the variable vowel but not from the variable final consonant context, suggesting that vowel variability but not all kinds of variability are beneficial. These results are discussed in the context of time-honored observations on the vowel-dependent nature of place of articulation cues for consonants.
Y1  - 2021
U6  - https://doi.org/10.1121/10.0003574
SN  - 2691-1191
VL  - 1
IS  - 2
PB  - AIP Publ.
CY  - Melville
ER  - 
TY  - JOUR
A1  - Sotiropoulou, Stavroula
A1  - Gibson, Mark
A1  - Gafos, Adamantios I.
T1  - Global organization in Spanish onsets
JF  - Journal of phonetics
N2  - This paper addresses the relation between syllable structure and inter-segmental temporal coordination. The data examined are Electromagnetic Articulometry recordings from six speakers of Central Peninsular Spanish (henceforth, Spanish), producing words beginning with the clusters /pl, bl, kl, gl, p(sic), k(sic), t(sic)/ as well as corresponding unclustered sonorant-initial words in three vowel contexts /a, e, o/. In our results, we find evidence for a global organization of the segments involved in these combinations. This is reflected in a number of ways: shortening of the prevocalic sonorant in the cluster-initial case compared to the unclustered case, reorganization of the relative timing of the internal CV subsequence (in a CCV) in the obstruent-lateral context, early vowel initiation, and a strong compensatory relation between the duration of the obstruent-to-lateral transition and the duration of the lateral. In other words, we find that the global organization presiding over the segments partaking in these tautosyllabic CCVs is pleiotropic, that is, simultaneously expressed over a set of different phonetic parameters rather than via a privileged metric such as c-center stability or any other such given single measure (employed in prior works).
KW  - syllables
KW  - inter-segmental coordination
KW  - Central Peninsular Spanish
KW  - obstruent-lateral clusters
KW  - obstruent-rhotic clusters
Y1  - 2020
U6  - https://doi.org/10.1016/j.wocn.2020.100995
SN  - 0095-4470
VL  - 82
PB  - Elsevier
CY  - London
ER  - 
TY  - JOUR
A1  - Mokari, Payam Ghaffarvand
A1  - Gafos, Adamantios I.
A1  - Williams, Daniel
T1  - Perceptuomotor compatibility effects in vowels
BT  - effects of consonantal context and acoustic proximity of response and distractor
JF  - JASA Express Letters
N2  - In a cue-distractor task, speakers' response times (RTs) were found to speed up when they perceived a distractor syllable whose vowel was identical to the vowel in the syllable they were preparing to utter. At a more fine-grained level, subphonemic congruency between response and distractor-defined by higher number of shared phonological features or higher acoustic proximity-was also found to be predictive of RT modulations. Furthermore, the findings indicate that perception of vowel stimuli embedded in syllables gives rise to robust and more consistent perceptuomotor compatibility effects (compared to isolated vowels) across different response-distractor vowel pairs.
KW  - speech
Y1  - 2021
U6  - https://doi.org/10.1121/10.0003039
SN  - 2691-1191
VL  - 1
IS  - 1
PB  - American Institute of Physics
CY  - Melville
ER  - 
TY  - JOUR
A1  - Kuberski, Stephan R.
A1  - Gafos, Adamantios I.
T1  - Fitts’ law in tongue movements of repetitive speech
JF  - Phonetica : international journal of phonetic science
N2  - Fitts' law, perhaps the most celebrated law of human motor control, expresses a relation between the kinematic property of speed and the non-kinematic, task-specific property of accuracy. We aimed to assess whether speech movements obey this law using a metronome-driven speech elicitation paradigm with a systematic speech rate control. Specifically, using the paradigm of repetitive speech, we recorded via electromagnetic articulometry speech movement data in sequences of the form /CV.../ from 6 adult speakers. These sequences were spoken at 8 distinct rates ranging from extremely slow to extremely fast. Our results demonstrate, first, that the present paradigm of extensive metronome-driven manipulations satisfies the crucial prerequisites for evaluating Fitts' law in a subset of our elicited rates. Second, we uncover for the first time in speech evidence for Fitts' law at the faster rates and specifically beyond a participant-specific critical rate. We find no evidence for Fitts' law at the slowest metronome rates. Finally, we discuss implications of these results for models of speech.
Y1  - 2021
U6  - https://doi.org/10.1159/000501644
SN  - 0031-8388
SN  - 1423-0321
VL  - 78
IS  - 1
SP  - 3
EP  - 27
PB  - De Gruyter Mouton
CY  - Berlin
ER  - 
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  - JOUR
A1  - Bürki-Foschini, Audrey Damaris
A1  - Viebahn, Malte Clemens
A1  - Gafos, Adamantios I.
T1  - Plasticity and transfer in the sound system
BT  - exposure to syllables in production or perception changes their subsequent production
JF  - Language, cognition and neuroscience
N2  - This study focuses on the ability of the adult sound system to reorganise as a result of experience. Participants were exposed to existing and novel syllables in either a listening task or a production task over the course of two days. On the third day, they named disyllabic pseudowords while their electroencephalogram was recorded. The first syllable of these pseudowords had either been trained in the auditory modality, trained in production or had not been trained. The EEG response differed between existing and novel syllables for untrained but not for trained syllables, indicating that training novel sound sequences modifies the processes involved in the production of these sequences to make them more similar to those underlying the production of existing sound sequences. Effects of training on the EEG response were observed both after production training and mere auditory exposure.
KW  - Language production
KW  - EEG
KW  - syllables
KW  - phonetic encoding
KW  - transfer
Y1  - 2020
U6  - https://doi.org/10.1080/23273798.2020.1782445
SN  - 2327-3798
SN  - 2327-3801
VL  - 35
IS  - 10
SP  - 1371
EP  - 1393
PB  - Routledge, Taylor & Francis Group
CY  - Abingdon
ER  - 
TY  - JOUR
A1  - Kuberski, Stephan R.
A1  - Gafos, Adamantios I.
T1  - The speed-curvature power law in tongue movements of repetitive speech
JF  - PLoS one
N2  - The speed-curvature power law is a celebrated law of motor control expressing a relation between the kinematic property of speed and the geometric property of curvature. We aimed to assess whether speech movements obey this law just as movements from other domains do. We describe a metronome-driven speech elicitation paradigm designed to cover a wide range of speeds. We recorded via electromagnetic articulometry speech movements in sequences of the form /CV…/ from nine speakers (five German, four English) speaking at eight distinct rates. First, we demonstrate that the paradigm of metronome-driven manipulations results in speech movement data consistent with earlier reports on the kinematics of speech production. Second, analysis of our data in their full three-dimensions and using advanced numerical differentiation methods offers stronger evidence for the law than that reported in previous studies devoted to its assessment. Finally, we demonstrate the presence of a clear rate dependency of the power law’s parameters. The robustness of the speed-curvature relation in our datasets lends further support to the hypothesis that the power law is a general feature of human movement. We place our results in the context of other work in movement control and consider implications for models of speech production.
Y1  - 2019
U6  - https://doi.org/10.1371/journal.pone.0213851
SN  - 1932-6203
VL  - 14
IS  - 3
PB  - PLoS
CY  - San Fransisco
ER  - 
TY  - GEN
A1  - Höhle, Barbara
A1  - Fritzsche, Tom
A1  - Meß, Katharina
A1  - Philipp, Mareike
A1  - Gafos, Adamantios I.
T1  - Only the right noise?
BT  - Effects of phonetic and visual input variability on 14-month-olds' minimal pair word learning
T2  - Zweitveröffentlichungen der Universität Potsdam : Humanwissenschaftliche Reihe
N2  - Seminal work by Werker and colleagues (Stager & Werker [1997]Nature, 388, 381-382) has found that 14-month-old infants do not show evidence for learning minimal pairs in the habituation-switch paradigm. However, when multiple speakers produce the minimal pair in acoustically variable ways, infants' performance improves in comparison to a single speaker condition (Rost & McMurray [2009]Developmental Science, 12, 339-349). The current study further extends these results and assesses how different kinds of input variability affect 14-month-olds' minimal pair learning in the habituation-switch paradigm testing German learning infants. The first two experiments investigated word learning when the labels were spoken by a single speaker versus when the labels were spoken by multiple speakers. In the third experiment we studied whether non-acoustic variability, implemented by visual variability of the objects presented together with the labels, would also affect minimal pair learning. We found enhanced learning in the multiple speakers compared to the single speaker condition, confirming previous findings with English-learning infants. In contrast, visual variability of the presented objects did not support learning. These findings both confirm and better delimit the beneficial role of speech-specific variability in minimal pair learning. Finally, we review different proposals on the mechanisms via which variability confers benefits to learning and outline what may be likely principles that underlie this benefit. We highlight among these the multiplicity of acoustic cues signalling phonemic contrasts and the presence of relations among these cues. It is in these relations where we trace part of the source for the apparent paradoxical benefit of variability in learning.
T3  - Zweitveröffentlichungen der Universität Potsdam : Humanwissenschaftliche Reihe - 868 
KW  - acoustic variability
KW  - habituation-switch paradigm
KW  - infant word learning
KW  - minimal pairs
KW  - phonological development
KW  - visual variability
Y1  - 2020
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-516674
SN  - 1866-8364
IS  - 5
ER  - 
TY  - JOUR
A1  - Höhle, Barbara
A1  - Fritzsche, Tom
A1  - Meß, Katharina
A1  - Philipp, Mareike
A1  - Gafos, Adamantios I.
T1  - Only the right noise?
BT  - Effects of phonetic and visual input variability on 14-month-olds' minimal pair word learning
JF  - Developmental Science
N2  - Seminal work by Werker and colleagues (Stager & Werker [1997]Nature, 388, 381-382) has found that 14-month-old infants do not show evidence for learning minimal pairs in the habituation-switch paradigm. However, when multiple speakers produce the minimal pair in acoustically variable ways, infants' performance improves in comparison to a single speaker condition (Rost & McMurray [2009]Developmental Science, 12, 339-349). The current study further extends these results and assesses how different kinds of input variability affect 14-month-olds' minimal pair learning in the habituation-switch paradigm testing German learning infants. The first two experiments investigated word learning when the labels were spoken by a single speaker versus when the labels were spoken by multiple speakers. In the third experiment we studied whether non-acoustic variability, implemented by visual variability of the objects presented together with the labels, would also affect minimal pair learning. We found enhanced learning in the multiple speakers compared to the single speaker condition, confirming previous findings with English-learning infants. In contrast, visual variability of the presented objects did not support learning. These findings both confirm and better delimit the beneficial role of speech-specific variability in minimal pair learning. Finally, we review different proposals on the mechanisms via which variability confers benefits to learning and outline what may be likely principles that underlie this benefit. We highlight among these the multiplicity of acoustic cues signalling phonemic contrasts and the presence of relations among these cues. It is in these relations where we trace part of the source for the apparent paradoxical benefit of variability in learning.
KW  - acoustic variability
KW  - habituation-switch paradigm
KW  - infant word learning
KW  - minimal pairs
KW  - phonological development
KW  - visual variability
Y1  - 2020
U6  - https://doi.org/10.1111/desc.12950
SN  - 1363-755X
SN  - 1467-7687
VL  - 23
IS  - 5
SP  - 1
EP  - 16
PB  - Wiley-Blackwell
CY  - Oxford
ER  - 
TY  - JOUR
A1  - Lialiou, Maria
A1  - Sotiropoulou, Stavroula
A1  - Gafos, Adamantios I.
T1  - Spatiotemporal coordination in word-medial stop-lateral and s-stop clusters of American English
JF  - Phonetica : international journal of phonetic science
N2  - This paper is concerned with the relation between syllabic organization and intersegmental spatiotemporal coordination using Electromagnetic Articulometry recordings from seven speakers of American English (henceforth, English). Whereas previous work on English has focused on word-initial clusters (preceding a vowel whose identity was not systematically varied), the present work examined word-medial clusters /pl, kl, sp, sk/ in the context of three different vowel heights (high, mid, low). Our results provide evidence for a global organization for the segments involved in these cluster-vowel combinations. This is reflected in a number of ways: compression of the prevocalic consonant and reduction of CV timing in the word-medial cluster case compared to its singleton paired word in both stop-lateral and s-stop clusters, early vowel initiation (as permitted by the clusters' phonetic properties), and presence of compensatory relations between phonetic properties of different segments or intersegmental transitions within each cluster. In other words, we find that the global organization presiding over the segments partaking in these word-medial tautosyllabic CCVs is pleiotropic, that is, simultaneously expressed in multiple phonetic exponents rather than via a privileged metric such as c-center stability or any other such given single measure employed in previous works.
KW  - American English
KW  - intersegmental coordination
KW  - s-stop clusters
KW  - stop-lateral clusters
KW  - syllabic structure
Y1  - 2021
U6  - https://doi.org/10.1515/phon-2021-2010
SN  - 0031-8388
SN  - 1423-0321
VL  - 78
IS  - 5-6
SP  - 385
EP  - 433
PB  - De Gruyter Mouton
CY  - Berlin
ER  - 
TY  - JOUR
A1  - Sotiropoulou, Stavroula
A1  - Gafos, Adamantios I.
T1  - Phonetic indices of syllabic organization in German stop-lateral clusters
JF  - Laboratory Phonology
N2  - Using articulatory data from five German speakers, we study how segmental sequences under different syllabic organizations respond to perturbations of phonetic parameters in the segments that compose them. Target words contained stop-lateral sequences /bl, gl, kl, pl/ in word-initial and cross-word contexts and were embedded in carrier phrases with different prosodic boundaries, i.e., no phrase boundary versus an utterance phrase boundary preceded the target word in the case of word-initial clusters, or separated the consonants in the case of cross-word sequences. For word-initial cluster (CCV) onsets, we find that increasing C1 stop duration or the lag between two consonants leads to earlier vowel initiation and reduced local timing stability across CV, CCV. Furthermore, as the inter-consonantal lag increases, C2 duration decreases. In contrast, for cross-word C#CV sequences, increasing inter-consonantal lag does not lead to earlier vowel initiation and robust local timing stability is maintained across CV, C#CV. In other words, in CCV sequences within words, local perturbations to segments have effects that ripple through the rest of the sequence. Instead, in cross-word C#CV sequences, local perturbations stay local. Overall, the findings indicate that the effects of phonetic perturbations on coordination patterns depend on the syllabic organization superimposed on these clusters.
Y1  - 2022
U6  - https://doi.org/10.16995/labphon.6440
SN  - 1868-6346
SN  - 1868-6354
VL  - 13
IS  - 1
PB  - Open Library of humanities
CY  - Cambridge
ER  -