Articulatory Gestures Research Articles

Are Vowels Normalized After Maxillary Osteotomy? An Acoustic Study in Cleft Lip and Palate

Maxillary hypoplasia is a common skeletal condition in cleft lip and palate (CLP). Maxillary osteotomy is typically used to reposition the maxilla in CLP with maxillary hypoplasia. Previous studies have suggested that vowel articulations are adjusted postsurgically due to altered vocal tract configuration and articulatory reorganization. This acoustic study aims to investigate whether vowels are normalized postoperatively and to explore the nature of articulatory reorganization. A prospective study was conducted to examine the vowel production of a group of individuals with CLP (N = 17) undergoing maxillary osteotomy and a group of normal controls (N = 20), using speech acoustic data. The data were collected at 0 to 3 months presurgery (T1), 3-months (T2), and 12-months (T3) postsurgery. General linear model repeated measures and independent t-tests were undertaken on F1, F2, and vowel space area. General linear model repeated measures revealed no main effects of time for F1 (F [2, 22] = 1.094, P = 0.352), F2 (F [2, 22] = 1.269, P = 0.301), and vowel space area (F [2, 28] = 0.059, P = 0.943). Independent t-tests showed statistically significant differences (P < 0.05) for all acoustic parameters and all vowels between the CLP and the normal groups at all time points. Vowels were not normalized after maxillary osteotomy despite positive anatomical changes within the oral cavity. Individuals with CLP tended to adjust their vowel articulatory gestures to match presurgical patterns. The nature of articulatory reorganization appears to be prompt, sensory-driven, complete, and permanent.

A First Step toward the Clinical Application of Landmark-Based Acoustic Analysis in Child Mandarin.

As an initial step for the clinical application of landmark-based acoustic analysis in child Mandarin, the study quantified the developmental trajectories of consonants produced by four-to-seven-year-old children who acquired Taiwanese Mandarin as their first language. The results from a total of 80 children (20 in each age group, with gender balanced) indicated that younger age groups produced more +b landmark features than seven-year-olds did, showing that the development of obstruents was not completed by the age of six. A multiple regression showed that the participants’ speech intelligibility scores could be predicted by landmark features. Additionally, the +b landmark feature demonstrated the strongest net effect on speech intelligibility scores. The findings indicated that: (a) the landmark feature +b was an essential indicator of speech development in child Mandarin and; (b) the consonantal development in child Mandarin could be predicted by the physiological complexity of the articulatory gestures. Future studies focusing on a wider range of population (e.g., typically developing adults, aging and other clinical groups) with different language backgrounds are encouraged to apply landmark-based acoustic analysis to trace the linguistic development of a particular group.

Paradigmatic enhancement of stem vowels in regular English inflected verb forms

Many theories of word structure in linguistics and morphological processing in cognitive psychology are grounded in a compositional perspective on the (mental) lexicon in which complex words are built up during speech production from sublexical elements such as morphemes, stems, and exponents. When combined with the hypothesis that storage in the lexicon is restricted to the irregular, the prediction follows that properties specific to regular inflected words cannot co-determine the phonetic realization of these inflected words. This study shows that the stem vowels of regular English inflected verb forms that are more frequent in their paradigm are produced with more enhanced articulatory gestures in the midsaggital plane, challenging compositional models of lexical processing. The effect of paradigmatic probability dovetails well with the Paradigmatic Enhancement Hypothesis and is consistent with a growing body of research indicating that the whole is more than its parts.

Toward a speech-motor account of the effect of Age of Pacifier Withdrawal

Recently published works suggest that prolonged pacifier use affects abstract word processing later in life. Using the pacifier beyond age 3 years affects the conceptual relations used to define the meaning of words at age 6 years. Similarly, when semantically categorizing a set of abstract, concrete and emotional words, children aged 8 years who used the pacifier for a longer period of time were slower to process abstract stimuli, but not concrete and emotional ones. The children of these studies had typical development and no diagnosis of cognitive or linguistic disorders. These results, although correlational, suggest a possible relationship between extended use of a pacifier and the development of language skills, particularly for abstract words.The first goal of this theoretical work is to outline current evidence suggesting an association between prolonged pacifier use and the processing of abstract words. The second goal is to propose an account of the effect of Age of Pacifier Withdrawal (APW) within the DIVA neurocomputational model of speech development and production (Guenther & Vladusich, 2013). Using the pacifier during social interaction for a longer period might impede the processing of proprioceptive information and speech-motor programs (i.e., by limiting the co-articulation of speech, it could inhibit the building and consolidation of speech-motor articulatory gestures) as well as auditory input (because the child receives inaccurate input about his/her own speech). Thus, it seems useful to explore the auditory speech representation of children who use a pacifier beyond 3 years of age. We suggest that after the first year of life pacifier use should be impeded during social interaction and limited to use at bed time.

The magnitude of articulatory gestures for the glide /w/ in Korean: Implications for the phonological representation of /w/

The magnitude of articulatory gestures for the glide /w/ in Korean: Implications for the phonological representation of /w/

Vocal drum sounds in human beatboxing: An acoustic and articulatory exploration using electromagnetic articulography.

Acoustic characteristics, lingual and labial articulatory dynamics, and ventilatory behaviors were studied on a beatboxer producing twelve drum sounds belonging to five main categories of his repertoire (kick, snare, hi-hat, rimshot, cymbal). Various types of experimental data were collected synchronously (respiratory inductance plethysmography, electroglottography, electromagnetic articulography, and acoustic recording). Automatic unsupervised classification was successfully applied on acoustic data with t-SNE spectral clustering technique. A cluster purity value of 94% was achieved, showing that each sound has a specific acoustic signature. Acoustical intensity of sounds produced with the humming technique was found to be significantly lower than their non-humming counterparts. For these sounds, a dissociation between articulation and breathing was observed. Overall, a wide range of articulatory gestures was observed, some of which were non-linguistic. The tongue was systematically involved in the articulation of the explored beatboxing sounds, either as the main articulator or as accompanying the lip dynamics. Two pulmonic and three non-pulmonic airstream mechanisms were identified. Ejectives were found in the production of all the sounds with bilabial occlusion or alveolar occlusion with egressive airstream. A phonetic annotation using the IPA alphabet was performed, highlighting the complexity of such sound production and the limits of speech-based annotation.

Speech errors and articulatory gestures: an electropalatographic investigation

One of the major findings of traditional investigations of speech errors is that a single segment is the smallest unit affected by speech errors, although the possibility that units smaller than the segment could play a role in explaining speech errors was not entirely rejected. A number of relatively recent studies using instrumental kinematic techniques for speech analysis bring evidence that errors often occur at subsegmental units of speech production, i.e. at the level of articulatory gestures. Such errors occur due to the coproduction of articulatory gestures, whereby the gestures from both the target consonant and the competing speech sound overlap. As they represent the gradient shift from one segment to another, they are often called gradient errors. Such processes are almost impossible to capture without the use of instrumental kinematic techniques, such as electropalatography (EPG). Th ere are no instrumental kinematic studies of speech errors in Croatian speech. Th us, the aim of this paper is to use EPG to investigate speech errors produced in one Croatian tongue twister. The analysis was focused on /r/ and /l/ targets produced by 10 native female speakers of Croatian, while producing the tongue twister which facilitated speech errors in these two sounds. Each token of the target consonant was classifi ed in one of the four categories: (1) perceptually and articulatorily correct production (P1A1); (2) articulatorily correct but perceptually incorrect production (P0A1); (3) perceptually correct but articulatorily incorrect production (P1A0) and (4) perceptually and articulatorily incorrect production (P0A0). Th e classifi cation was made by the authors via auditory analysis and visual inspection of spectrograms and electropalatograms prior to the quantitative kinematic analysis. Subsequent analyses showed evidence of gradient errors, which would not be detected without the use of instrumental kinematic techniques. Th is investigation supports the claim that traditional method of collecting speech errors by perceptual analysis only is not sensitive enough to detect the subtleties of erroneous productions and speech motor control.

Multimodal Second-Language Communication: Research Findings and Pedagogical Implications

This article reviews research findings involving visual input in speech processing in the form of facial cues and co-speech gestures for second-language (L2) learners, and provides pedagogical implications for the teaching of listening and speaking. It traces the foundations of auditory–visual speech research and explores the role of a speaker’s facial cues in L2 perception training and of gestural cues in listening comprehension. There is a strong role for pedagogy to maximize the salience of multimodal cues for L2 learners. Visible articulatory gestures that precede the acoustic signal and the preparation phase of a hand gesture that precedes the acoustic onset of a word provide a priming effect on perceivers’ attention to signal upcoming information and facilitate processing, and visible gestures that co-occur with speech aid ongoing processing and comprehension. L2 learners benefit from an awareness of these visual cues and exposure to input.

Neuromotor Control of Speech and Speechlike Tasks: Implications From Articulatory Gestures

Purpose This study aimed to provide a preliminary examination of the articulatory control of speech and speechlike tasks based on a gestural framework and identify shared and task-specific articulatory factors in speech and speechlike tasks. Method Ten healthy participants performed two speechlike tasks (i.e., alternating motion rate [AMR] and sequential motion rate [SMR]) and three speech tasks (i.e., reading of “clever Kim called the cat clinic” at the regular, fast, and slow rates) that varied in phonological complexity and rate. Articulatory kinematics were recorded using an electromagnetic kinematic tracking system (Wave, Northern Digital Inc.). Based on the gestural framework for articulatory phonology, the gestures of tongue body and lips were derived from the kinematic data. These gestures were subjected to a fine-grained analysis, which extracted (a) four gestural features (i.e., range of magnitude [ROM], frequency [Freq], acceleration time, and maximum speed [maxSpd]) for the tongue body gesture; (b) three intergestural measures including the peak intergestural coherence (InterCOH), frequency at which the peak intergestural coherence occurs (Freq_InterCOH), and the mean absolute relative phase between the tongue body and lip gestures; and (c) three intragestural (i.e., interarticulator) measures including the peak intragestural coherence (IntraCOH), Freq_IntraCOH, and mean absolute relative phase between the tongue body and the jaw, which are the component articulators that underlie the tongue body gesture. In addition, the performance rate for each task was also derived. The effects of task and sex on all the articulatory and behavioral measures were examined using mixed-design analysis of variance followed by post hoc pairwise comparisons across tasks. Results Task had a significant effect on performance rate, ROM, Freq, maxSpd, InterCOH, Freq_InterCOH, IntraCOH, and Freq_IntraCOH. Compared to the speech tasks, the AMR task showed a decrease in ROM and increases in Freq, InterCOH, Freq_InterCOH, IntraCOH, and Freq_IntraCOH. The SMR task showed similar ROM, Freq, maxSpd, InterCOH, and IntraCOH as the fast and regular speech tasks. Conclusions The simple phonological structure and demand for rapid syllable rate for the AMR task may elicit a distinct articulatory control mechanism. Despite being a rapid nonsense syllable repetition task, the relatively complex phonological structure of the SMR task appeared to elicit a similar articulatory control mechanism as that of speech production. Based on these shared and task-specific articulatory features between speech and speechlike tasks, the clinical implications for articulatory assessment were discussed.

The rise of languaging

In this paper, we turn to languaging, defined here as activity in which wordings play a part. On such a view, while activity is paramount, people also orient to acts of vocalization as wordings. These physical wordings can be used as tools that shape attending, with recourse to neither mental representations nor symbols that store and transmit information. The view is consistent with macroevolutionary continuity and will be used to challenge appeal to a major evolutionary transition to ‘language’. On the languaging view, like many modern social primates, hominins have long undertaken encultured activities. Infants, human and nonhuman, act epistemically and, by so doing, align skills with objects to practice. They develop a ‘stance’ to pragmatic, goal-directed action. In human ontogenesis, we argue, both epistemic action and the stance-taking are extended by vocalizing. Caregiver-infant coordination enables vocalizing to be integrated with acting, attending, perceiving and managing one’s attention. Infants also self-entrain vocalizing through ‘babble’. Once the developmental threads unite, social reaching (Bates, 1976) favors a special stance to articulatory gestures (one that allows wordings to be made and heard). Just as in orienting to cultural tools, a child grasps a community’s ways-with-wordings. The latter often express abstract relations which we can illustrate with modern non-literate use of reciprocal expressions. In Australian and Pacific languages, reciprocals sustain coordinating that, for speakers, is neither symbolic nor arbitrary. Further, cross-linguistic comparison shows the same ‘patchy distribution’ of reciprocals that characterizes primate tool use. Of course, we do not deny that, in many language games, people can undertake activity that makes symbolic use of wordings. In modern literate societies, abilities based on social reaching are further extended into skills that use notational practices (e.g. letters, numbers, graphics). This opens up whole new fields or domains of languaging. Yet, ostensive use of symbols is plainly a cultural invention – not a direct legacy of hominin evolution.

Duration of the rhotic approximant /ɹ/ in spastic dysarthria of different severity levels

Dysarthria is a motor speech disorder leading to imprecise articulation of speech. Acoustic analysis capable of detecting and assessing articulation errors is useful in dysarthria diagnosis and therapy. Since speakers with dysarthria experience difficulty in producing rhotics due to complex articulatory gestures of these sounds, the hypothesis of the present study is that duration of the rhotic approximant /ɹ/ distinguishes dysarthric speech of different severity levels. Duration measurements were conducted using the third formant (F3) trajectories estimated from quasi-closed-phase (QCP) spectrograms. Results indicate that the severity level of spastic dysarthria has a significant effect on duration of /ɹ/. In addition, the phonetic context has a significant effect on duration of /ɹ/, the ɪ-r-ɛ context showing the largest difference in /ɹ/ duration between dysarthric speech of the highest severity levels and healthy speech. The results of this preliminary study can be used in the future to develop signal processing and machine learning methods to automatically predict the severity level of spastic dysarthria from speech signals.

What is and what is not an articulatory gesture in speech production

Articulatory data are provided showing that, in languages in which they have phonemic status, (alveolo)palatal consonants, dark /l/ and the trill /r/ are articulated with a single lingual gesture instead of two independent tongue front and tongue body gestures. They are therefore simple, not complex segments. It is argued that tongue body lowering and retraction for dark /l/ and the trill /r/ is associated with manner of articulation requirements and with requirements on the implementation of the darkness percept in the case of dark /l/, and that tongue body raising and fronting for (alveolo)palatals results naturally from the contraction of the genioglossus muscle. These consonant units resemble truly complex palatalized and velarized or pharyngealized dentoalveolars regarding lingual configuration and kinematics, as well as coarticulatory efects and phonological and sound change processes. Contrary to some views, the study also contends that clear /l/ and the tap /?/ are not complex segments but consonants articulated with a more or less neutral tongue body configuration which is subject to considerable vowel coarticulation.

Detecting anticipatory information in speech with signal chopping

Most analyses of articulatory processes in speech assume that word form-related changes in the state of the vocal tract have well-defined beginnings and ends. But how do we determine the precise moments in time when these beginnings and ends occur? More specifically, when should we expect information related to the sound categories of a word to be present in acoustic and articulatory signals? The framework of Articulatory Phonology/Task Dynamics predicts that the earliest time such information becomes available is when the first articulatory gesture of a word becomes active, which closely corresponds to when a movement is initiated. Alternatively, a recent extension of the Articulatory Phonology model holds that gestures may have an influence on the state of the vocal tract after they have been retrieved from memory, but before they become active and before canonical movement initiation. This paper presents evidence that indeed, anticipatory information is available much earlier than is typically assumed: the identity of a syllable onset gesture can be predicted from articulatory and acoustic data quite early, in some cases nearly half a second before movement initiation. Likewise, the identity of a coda gesture can be predicted during the period of time typically associated with an onset consonant. These findings were obtained with a novel analysis method called signal chopping which was paired with deep neural network based classification. In this approach articulatory and acoustic signals are systematically truncated in space and time, and a network training/test procedure is repeated on the chopped signals. By analyzing the effects of chopping on classification accuracy, gesture-specific information can be spatiotemporally localized.

Speech rehabilitation in post-stroke aphasia using visual illustration of speech articulators: A case report study

ABSTRACT Recent studies on the remediation of speech disorders suggest that providing visual information of speech articulators may contribute to improve speech production. In this study, we evaluate the effectiveness of an illustration-based rehabilitation method on speech recovery of a patient with non-fluent chronic aphasia. The Ultraspeech-player software allowed visualization by the patient of reference tongue and lip movements recorded using ultrasound and video imaging. This method can improve the patient’s awareness of their own lingual and labial movements, which can increase the ability to coordinate and combine articulatory gestures. The effects of this method were assessed by analyzing performance during speech tasks, the phonological processes identified in the errors made during the phoneme repetition task and the acoustic parameters derived from the speech signal. We also evaluated cognitive performance before and after rehabilitation. The integrity of visuospatial ability, short-term and working memory and some executive functions supports the effectiveness of the rehabilitation method. Our results showed that illustration-based rehabilitation technique had a beneficial effect on the patient’s speech production, especially for stop and fricative consonants which are targeted (high visibility of speech articulator configurations) by the software, but also on reading abilities. Acoustic parameters indicated an improvement in the distinction between consonant categories: voiced and voiceless stops or alveolar, post-alveolar and labiodental fricatives. However, the patient showed little improvement for vowels. These results confirmed the advantage of using illustration-based rehabilitation technique and the necessity of detailed subjective and objective intra-speaker evaluation in speech production to fully evaluate speech abilities.

Articulatory and perceptual cues to non-native phoneme perception: Cross-modal training for early learners

Non-native phoneme perception can be challenging for adult learners. This article explores two routes to strengthening early representations of non-native targets: perceptual training, which focuses on auditory discrimination of novel contrasts, and articulatory training, which highlights the articulatory gestures of non-native categories. Of particular interest is whether cross-modal transfer from production to perception is beneficial to improving discrimination. A longitudinal experiment integrating both training types found that articulatory training did not improve discrimination once perceptual learning had taken place. However, a follow-up experiment found an equivalent benefit for perceptual and articulatory training when each was presented as the only learning style to separate groups of learners. These findings suggest that articulatory learning can ‘cross over’ to assist acquisition in the perceptual domain, and may play a key role for second language (L2) learners struggling with both perception and production of novel phoneme categories.

On the timing and coordination of articulatory movements: Historical perspectives and current theoretical challenges

AbstractThe timing and coordination of articulatory movements is essential to producing speech. A considerable body of literature explores the cognitive and motor control mechanisms involved. This review provides an accessible introduction to that literature, while highlighting articulatory phenomena that challenge prevailing views. We begin with the concept of dynamic articulatory gestures, and their role in the coproduction account of coarticulation. We then outline prominent accounts of gestural coordination. These accounts generally assume that speech planning involves the selection of coarsely grained units, which then unfold involuntarily. Later we consider evidence that speakers rapidly adapt to surprising acoustic feedback, that they plan around the expected timing of upcoming acoustic consequences, and that they reshape the articulatory time course on the fly. These findings suggest that movements can be flexibly modified, and that execution can considerably overlap planning. We advocate for speech models that permit speakers fine‐grained control over unfolding articulation.

Acoustic correlates of plosive voicing in Madurese.

Madurese, a Malayo-Polynesian language of Indonesia, is of interest both areally and typologically: it is described as having a three-way laryngeal contrast between voiced, voiceless unaspirated, and voiceless aspirated plosives, along with a strict phonotactic restriction on consonant voicing-vowel height sequences. An acoustic analysis of Madurese consonants and vowels obtained from the recordings of 15 speakers is presented to assess whether its voiced and aspirated plosives might share acoustic properties indicative of a shared articulatory gesture. Although voiced and voiceless aspirated plosives in word-initial position pattern together in terms of several spectral balance measures, these are most likely due to the following vowel quality, rather than aspects of a shared laryngeal configuration. Conversely, the voiceless (aspirated and unaspirated) plosives share multiple acoustic properties, including F0 trajectories and overlapping voicing lag time distributions, suggesting that they share a glottal aperture target. The implications of these findings for the typology of laryngeal contrasts and the historical evolution of the Madurese consonant-vowel co-occurrence restriction are discussed.

On pharyngealized vowels in Northern Horpa: An acoustic and ultrasound study.

In the Northern Horpa (NH) language of Sichuan, vowels are divided between plain and pharyngealized sets, with the latter pronounced with auxiliary articulatory gestures involving more constriction in the vocal tract. The current study examines how the NH vocalic contrast is manifested in line with the process of pharyngealization both acoustically and articulatorily, based on freshly gathered data from two varieties of the language (i.e., Rtsangkhog and Yunasche). Along with formant analyses, ultrasound imaging was employed to capture the tongue postures and positions during vowel production. The results show that in contrast with plain vowels, pharyngealized vowels generally feature lower F2 values and higher F1 and F3 values. Mixed results for F2 and F3 suggest that the quality contrasts are vowel-dependent. Ultrasound images, on the other hand, reveal that the vocalic distinction is affected by different types of tongue movements, including retraction, backing, and double bunching, depending on the inherent tongue positions for each vowel. The two NH varieties investigated are found to display differential formant changes and different types of tongue displacements. The formant profiles along with ultrasound images support the view that the production of the NH phonologically marked vowels is characteristic of pharyngealization.

The nonlinear gestural model of speech apraxia: clinical implications and applications

ABSTRACT Rationale: In the approach presented here, adult apraxia of speech (AoS) is understood as a disorder affecting the language-specific motor patterns a speaker acquires during childhood and adolescence. The phonological factors that influence articulatory accuracy in AoS reflect the relative vulnerability of their accompanying motor planning variables to apraxic impairment, depending on the extent to which they have been consolidated in speech motor learning. Since these factors interact strongly, the Nonlinear Gestural (NLG) model combines them into an integrative computational framework. We thereby aim at explaining word production accuracy in AOS from a word’s structural properties across multiple hierarchical layers, – from articulatory gestures to metrical patterns. The NLG model: In a review of earlier articles, the NLG-model is first introduced by describing five core principles underlying its design, whereupon the computational and empirical underpinnings of the model are explained. Finally, the model shape is delineated by specifying its empirically derived coefficients, with a focus on clinical implications. Clinical applications: A web-based NLG calculator is described that allows clinicians to compute NLG scores for German words or pseudowords and create displays of their gestural scores, as a prerequisite of incorporating the NLG approach in their diagnostic and therapeutic work. Furthermore, we describe how the structural properties of words, as represented by their NLG scores, can be linked to other clinically relevant lexical variables. Potential applications of these tools involve (i) the design of assessment and treatment materials following a hierarchy of articulatory difficulty, (ii) the interpretation of error patterns following the NLG hierarchy as a signature of the apraxic pathomechanism, with possible differential diagnostic applications, and (iii) computation of a distance metric to describe the relationship between target words and their realisations by patients with AoS. Expansions to other types of speech sound impairment in adults and children are discussed.

Phonatory and articulatory representations of speech production in cortical and subcortical fMRI responses

Speaking involves coordination of multiple neuromotor systems, including respiration, phonation and articulation. Developing non-invasive imaging methods to study how the brain controls these systems is critical for understanding the neurobiology of speech production. Recent models and animal research suggest that regions beyond the primary motor cortex (M1) help orchestrate the neuromotor control needed for speaking, including cortical and sub-cortical regions. Using contrasts between speech conditions with controlled respiratory behavior, this fMRI study investigates articulatory gestures involving the tongue, lips and velum (i.e., alveolars versus bilabials, and nasals versus orals), and phonatory gestures (i.e., voiced versus whispered speech). Multivariate pattern analysis (MVPA) was used to decode articulatory gestures in M1, cerebellum and basal ganglia. Furthermore, apart from confirming the role of a mid-M1 region for phonation, we found that a dorsal M1 region, linked to respiratory control, showed significant differences for voiced compared to whispered speech despite matched lung volume observations. This region was also functionally connected to tongue and lip M1 seed regions, underlying its importance in the coordination of speech. Our study confirms and extends current knowledge regarding the neural mechanisms underlying neuromotor speech control, which hold promise to study neural dysfunctions involved in motor-speech disorders non-invasively.