Adamantios I. Gafos

We offer an intrinsic timing account of durations widely used to characterize inter-segmental coarticulation or coproduction patterns cross-linguistically. In this account, measured durations are the result of dynamical properties of the coarticulated segments. Our account is developed on the basis of timing data, registered using Electromagnetic a...

Acoustic variability in the speech input has been shown, in certain contexts, to be beneficial during infants' acquisition of sound contrasts. One approach attributes this result to the potential of variability to make the stability of individual cues visible. Another approach suggests that, instead of highlighting individual cues, variability unco...

Using articulatory data from five Spanish speakers, we study how stop-lateral-vowel sequences respond to perturbations of phonetic parameters in the segments that compose them. Target words with stop-lateral complex onsets were embedded in different prosodic contexts. Regardless of prosodic context, stability-based indices for the presumed global o...

This short report presents some preliminary results from electromagnetic articulography (EMA) recordings of Hindi Consonant-Vowel (CV) sequences. We specifically asked if and how articulatory timing in CV, quantified by the interval from V-target to C-offset, is modulated by consonant phonation, consonant place of articulation and vowel quality. Re...

Purpose We compare two signal smoothing and differentiation approaches: a frequently used approach in the speech community of digital filtering with approximation of derivatives by finite differences and a spline smoothing approach widely used in other fields of human movement science. Method In particular, we compare the values of a classic set o...

When encountering an unfamiliar accent, a hypothesized perceptual challenge is associating its phonetic realizations with the intended phonemic categories. Greater accumulated exposure to the language might afford richer representations of phonetic variants, thereby increasing the chance of detecting unfamiliar accent speakers’ intended phonemes. T...

Evaluating any model underlying the control of speech requires segmenting the continuous flow of speech effectors into sequences of movements. A virtually universal practice in this segmentation is to use a velocity-based threshold which identifies a movement onset or offset as the time at which the velocity of the relevant effector breaches some t...

In data from English and German clusters (C1C2), we examine if and how the stiffness of C1 opening and C2 closing movements (the two relevant movements in the C1-to-C2 transition) modulate overlap, using four overlap measures. Results show a variegated picture where different overlap measures do or do not depend on the stiffness parameters. We seek...

The primitives of phonological theory—whether we call them features, elements, gestures, or by some other name—stand in some relation to phonetic reality. Although there is consensus about this, there seems to be little agreement about most of the specifics involved. How many features are there? Are they privative or binary? Do segments need to be...

Recently, Roon, Hoole, Zeroual, Du, and Gafos (2021) have offered evidence that an empirical estimate of stiffness, a parameter in the dynamics hypothesized to control the kinematics of gestures, modulates overlap in consonant clusters of Moroccan Arabic. Here, we extend the Roon et al. (2021) study in two ways. First, empirically, we broaden the a...

Using data from Arabic C1C2 sequences, Gafos et al. (2020) show that the later C2 initiates its movement in reference to C1 constriction release, the higher the amplitude-normalized peak velocity (also known as stiffness; Cooke 1980, Kelso 1986) of C2’s closing movement. Similar relations between stiffness and movement onset are found in other area...

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 clusters /bl, gl, kl, pl/ in a word-initial and a cross-word context and were embedded in carrier phrases wi...

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 systemati...

It has been claimed that patterns of regressive place assimilation in consonant clusters are attributable to the ‘inherent velocities’ of the primary oral articulators involved. The present study used articulatory data from Moroccan Arabic to evaluate whether there were reliable differences in peak velocity or measured stiffness based on primary or...

In the context of Artificial Grammar Learning (AGL) experiments, it is possible to quantify how effectively a stimulus has conveyed information and specifically the information the experimenter thinks it was designed to convey. At the most basic level, this can be done if one has access to the response variability of independent responses to the sa...

I argue that properties of memory, a so far largely neglected source of explanation in phonological patterns, offer a grounding for a number of not well understood traits of long distance consonantal restrictions(both dissimilatory and assimilatory).

Fourteen-month-olds' ability to distinguish a just learned word, /buːk/, from its minimally different word, /duːk/, 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 var...

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 o...

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, pɾ, kɾ, tɾ/ as well as corresponding unclustered so...

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 sylla...

Spoken language is conveyed via well-coordinated speech movements, which act as coherent units of control referred to as gestures. These gestures and their underlying movements show several distinctive properties in terms of lawful relations among the parameters of duration, relative timing, range of motion, target accuracy, and speed. However, cur...

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 phon...

Seminal work by Werker and colleagues (Stager & Werker, 1997) 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...

We update our understanding of the view that grammar regulates inter-segmental temporal coordination and present an extension of that view to a new domain: we argue that inter-segmental coordination is basic to prosody. It is the glue joining segments together differently in different languages (here, illustrated with examples from Arabic and Spani...

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...

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 ar...

Although recent research has shed some light on relative timing in laryngeal and oral articulatory gestures, little is known about articulatory patterns of second language (L2) users along the trajectory from novice to expert. We report results of an electromagnetic articulographic (EMA) investigation of two native English speakers' L2 Spanish-lang...

Phonetic accommodation in fundamental frequency (f0) is of particular interest because it is not contrastive in English yet it covaries with contrastive parameters such as voice onset time (VOT). Accommodation in f0 additionally varies by speaker gender. In this investigation, we tested for f0 accommodation in 10 Korean-English bilinguals and 10 En...

Phonetic accommodation in fundamental frequency (f0) is of particular interest because it is not contrastive in English yet it covaries with contrastive parameters such as voice onset time (VOT). Accommodation in f0 additionally varies by speaker gender. In this investigation, we tested for f0 accommodation in 10 Korean-English bilinguals and 10 En...

The richness of consonant contrasts in MA offers an opportunity to test hypotheses about contextual variability of tongue positions during /C/ and /V/ in /VCV/ symmetric vowel contexts. This study focuses on V-to-C coarticulation influence and aims to better characterize for the first time the degree of such coarticulation as a function of the diff...

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 wi...

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...

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/. Durat...

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...

In the field of phonetics, voice onset time (VOT) is a major parameter of human speech defining linguistic contrasts in voicing. In this article, a landmark-based method of automatic VOT estimation in acoustic signals is presented. The proposed technique is based on a combination of two landmark detection procedures for release burst onset and glot...

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...

In investigations of phonetic accommodation, convergence is the most frequently reported finding (e.g., Babel, 2012). However, divergence is also attested under some circumstances (Giles, Coupland & Coupland 1991). On the basis of observations and modeling of Tobin and Nam (2009), Tobin, Nam and Fowler (under review) and Kopecz and Schöner (1995),...

EMA study of jaw movements during Moroccan Arabic consonants Our observations suggest that the degree of jaw involvement is crucial during coronal voiceless obstruent /s S t T/ (S T : pharyngealized cosonants). /t T/have similar height even though /t/ is laminal and /T/ apical: Apicality seems not always correlated with jaw lowering. The high jaw p...

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 speake...

This study introduces a method ideally suited for investigating toddlers’ ability to detect mispronunciations in lexical representations: pupillometry. Previous research has established that the magnitude of pupil dilation reflects differing levels of cognitive effort. Building on those findings, we use pupil dilation to study the level of detail e...

A series of hypotheses are addressed vis-à-vis the effects of syllable complexity and voicing on consonant duration and VOT (voice onset time) in a subset of Spanish clusters. Electropalatographic (EPG) and acoustic signals were obtained for native-speakers of Standard Peninsular Spanish producing clusters within and across word boundaries. The res...

It has been argued that the duration ratio (DR) of two consonants in C1C2 serves as a diagnostic of syllabification: if greater than 1, then C1C2 is a syllable onset; if (approximately) 1, C1C2 is a coda– onset sequence. If valid, this diagnostic would provide a straightforward way of assessing syllabic organization. We examined the validity of the...

Past studies have demonstrated that reaction times in producing CV syllables are modulated by audio distractors participants hear while preparing their responses. Galantucci et al. [5] showed that participants respond faster on trials with identical response-distractor pairs than when the response and distractor differ in voicing or articulator. Th...

Recent findings indicate that early lexical representations contain sub-phonemic information: When presented with known words, children are sensitive to manner, place and voicing feature changes (Mani and Plunkett, 2011; White and Morgan, 2008). However, due to the methodological challenges in child language research, the level of detail and the fa...

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...

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...

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 s...

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: consonant...

This paper deals with the factors behind temporal overlap differences in word medial [bd, db, bg, gb, gd, dg] clusters produced by speakers of Moroccan Arabic (MA). It is argued that certain overlap differences in these MA clusters are related to motor constraints. Specifically, these differences can be attributed to intrinsic physiological propert...

With the EMA technique we showed that post-lexical word initial [dd] of Moroccan Arabic is produced by our three speakers with a longer acoustic duration and articulatory gesture compared to its initial [d] cognate. The tongue tip gesture during initial [dd] and [d] generally have statistically similar height and amplitude. For two speakers, no sig...

In this study using 3-dimensional EMA (AG500 Carstens Medizinelektronik) we tried to characterize the temporal relations between consonant and vowels in [ab(b)i] contexts. We found that, [bb] has a consonantal gesture (LowerLip_y) whose total duration and plateau phase are longer and the vertical target higher compared to [b]. We also found an anti...

This article explores issues relating to the organizing structures of speech. Combinatorial phonological units are discrete, qualitative, and context-invariant, while speech is continuous and highly context-dependent. A gesture is a functional unit of action that achieves a specified task. Laboratory phonology work has developed both theoretical mo...

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 tempora...

Brought together in this volume are fourteen studies using a range of modern instrumental methods – acoustic and articulatory – to investigate the phonetics of several North African and Middle Eastern varieties of Arabic. Topics covered include syllable structure, quantity, assimilation, guttural and emphatic consonants and their pharyngeal and lar...

In linguistic theory, there is a tension between two core aims of the field: theoretical parsimony and empirical coverage of the remarkable diversity and specificity seen in linguistic data. Vowel harmony, and more specifically the two phenomena of transparency and opacity in vowel harmony that concern us in this chapter, provide prime examples of...

This paper examines inter-consonantal temporal overlap in Moroccan Arabic clusters using electromagnetic articulography. We distinguish two types of vari-ation in overlap: one is due to non-grammatical influences, the other is arguably linked to morpho-phonological distinctions in the grammar. From the first type, we extract a hypothesis that makes...

This paper develops computational tools for evaluating competing syllabic parses of a phonological string on the basis of temporal patterns in speech production data. This is done by constructing models linking syllable parses to patterns of coordination between articulatory events. Data simulated from different syllabic parses are evaluated agains...

Competing proposals on the syllabification of initial consonants in Moroccan Arabic are evaluated using a combination of experimental and modelling techniques. The proposed model interprets an input syllable structure as a set of articulatory landmarks coordinated in time. This enables the simulation of temporal patterns associated with the input s...

Neutral vowels are vowels that may intervene between the trigger and target of a harmony pattern even when they bear the opposite value for the harmonizing feature. Despite the significant body of work on and the crucial role of vowel harmony in phonological theory, surprisingly little attention has been devoted to the low-level phonetic properties...

Competing proposals on the syllabification of initial consonants in Moroccan Arabic are evaluated using a combination of experimental and modelling techniques. The proposed model interprets an input syllable structure as a set of articulatory landmarks coordinated in time. This enables the simulation of temporal patterns associated with the input s...

Moroccan Arabic (MA) geminate coronals are produced intervocalically with a longer oral closure and longer period of alveolar contact. MA geminate consonants don't induce shortening of their preceding vowel, and are produced without larger anticipation of their gesture in the preceding vowel compared to their simple cognates. Our data show that gem...

[Superceded by a Roon et al. 2021 Laboratory Phonology journal paper:] Comparatively little is known about the role that the speed of different articulatory movements plays in speech production. Using 3D Electromagnetic Articulography, the present experiment analyzes articulatory data from Moroccan Arabic for independent influences of oral articula...

Using a combination of magnetometry and ultrasound, we examined the articulatory characteristics of the so-called 'transparent' vowels [i], [i], and [e] in Hungarian vowel harmony. Phonologically, transparent vowels are front, but they can be followed by either front or back suffixes. However, a finer look reveals an underlying phonetic coherence i...

A fundamental problem in spoken language is the duality between the continuous aspects of phonetic performance and the discrete aspects of phonological competence. We study 2 instances of this problem from the phenomenon of voicing neutralization and vowel harmony. In each case, we present a model where the experimentally observed continuous distin...

A fundamental problem in spoken language is the duality between the continuous aspects of phonetic performance and the discrete aspects of phonological competence. We study a specific instance of this problem in Hungarian vowel harmony. We present a model where continuous phonetic distinctions uncovered by our experiments are linked to the discrete...

Does the productive use of language stem from the manipulation of mental variables (e.g. "noun", "any consonant")? If linguistic constraints appeal to variables, rather than instances (e.g. "dog", "m"), then they should generalize to any representable novel instance, including instances that fall beyond the phonological space of a language. We test...

How different is the phonology and morphology of nontemplatic (concatenative) word formation from that of templatic (nonconcatenative) word formation? In this article, I focus on the Arabic verbal system, the prototypical example of templatic morphology, with the aim of deriving some of its distinctly special traits from basic principles. The key n...

Linguistic form is expressed in space, as articulators effectconstrictions at various points in the vocal tract, but also in time, as articulators move. A rather widespread assumption in theories of phonology and phonetics is that the temporal dimension of speech is largely irrelevant to the description and explanation of the higher-level or more q...

Does the productive use of language stem from the manipulation of mental variables (e.g. "noun", "any consonant")? If linguistic constraints appeal to variables, rather than instances (e.g. "dog", "m"), then they should generalize to any representable novel instance, including instances that fall beyond the phonological space of a language. We test...

The papers in this collection derive from the Annual Symposia on Arabic Linguistics held in Stanford (1999) and Berkeley (2000). The selection is noteworthy for its diversity of approach, and for a noticeable broadening of the kinds of questions that are being asked and the kind of data being gathered about Arabic in various settings. These papers...

Abstract Semitic verbs exhibit a well-known prohibition against forms with initial gemination, *ssam, or with an initial sequence of two identical consonants, *sasam, alongside an abundance of forms with final gemination or final identity such as samm, samam(Greenberg 1950). This asymmetry has received considerable attention in the literature. Past...

This paper discusses data from the nominal paradigms of two dialectal varieties of East Lesvos, those of Thermi and Pamfila. It is shown that there is abundant evidence for the key role of the paradigm in the phonological realization of the [noun-clitic] clusters. We argue that the grammars of these dialectal varieties must crucially include constr...

We present novel results from the acoustic and articulatory investigation of the production of the transparent vowels (TVs) /i/, /i:/, /e:/ in Hungarian (colon denotes length). The acoustic measurements of the front-back distinction (second formant, the difference of the first and second formants [Ladefoged, 1993]) show that the effect of adjacent...

In this squib I discuss an unusual type of reduplication in which the reduplicant varies not only in terms of its phonemic composition but also in terms of its prosodic shape. The variability in the shape of the reduplicant results from a grammar that does not impose any constraint particular to the shape of the reduplicant per se. Further, I demon...

Past theoretical analyses have claimed that some languages employ a special type of phonological spreading of a consonant over a vowel, long-distance consonantal spreading. I argue that this type of spreading can and must be eliminated from the theory, by reducing it to segmental copying as in reduplication. This elimination is first motivated from...

Thesis (Ph. D.)--Johns Hopkins University, 1997. Vita. U.M.I. no. 9718956. Includes bibliographical references (l. [301]-327). Microfilm.

1. Introduction Vowel harmony is a requirement by which vowels in a certain domain agree in one or more phonetic features. 1 In Hungarian, the feature subject to harmony is the horizontal position of the tongue ([±back]). In many Hungarian roots, vowels in a word are either all front or all back, as in öröm 'joy', város 'city' (umlaut denotes front...