Oral Articulation Research Articles

Conforto e fonação com a nova geração de bráquetes ortodônticos linguais individualizados

TEMA: recentemente o número de pacientes desejando um tratamento ortodôntico e estético ao mesmo tempo aumentou consideravelmente. A técnica lingual oferece a opção mais estética de tratamento ortodôntico, pois os bráquetes ficam invisíveis colados na superfície lingual dos dentes e os lábios não ficam protuberantes. Apesar da grande vantagem estética, essa terapia possui desvantagens como restrição no conforto oral, na fala, na higiene, irritações na língua, restrição no espaço da língua e dificuldades na alimentação. Para amenizar essas desvantagens uma nova geração de bráquetes linguais otimizados ao máximo através da individualização das bases dos bráquetes, da posição de colagem e dos fios utilizados no tratamento ortodôntico foi desenvolvida recentemente. OBJETIVO: realizar uma revisão sistemática da literatura para verificar a adaptação do paciente a diferentes dispositivos ortodônticos linguais e a influência desses dispositivos no conforto e na fala, principalmente. CONCLUSÃO: atualmente a literatura suporta que os bráquetes linguais de última geração individualizados por computador proporcionam maior conforto e facilidade na fonação quando comparados aos bráquetes tradicionais da técnica lingual. No entanto, o sucesso na terapia requer orientações detalhadas sobre o potencial de restrição do conforto oral, articulação de palavras, mastigação e higiene oral, independente do sistema de bráquetes a ser utilizado.

The effect of articulatory placement on acoustic characteristics of nasalization.

Vowels adjacent to nasal consonants (/m/, /n/, /ŋ/ in English) tend to be nasalized. The effect of velopharyngeal opening on vowel nasalization has been studied by Feng et al. (1996) and Pruthi et al. (2007) with a transmission line model of the vocal tract based on MRI data of the area function. In order to find out the effect of articulatory placement on acoustic properties of nasalized vowels, the current study simulated the transfer function of coarticulated vowels in different nasal‐vowel utterances. The results revealed different acoustic characteristics of the same vowel in various nasal contexts, which demonstrated the effect of articulatory placement on vowel nasalization and suggested the possibility for oral articulation to compensate for spectral changes caused by failure of velopharyngeal closure among hypernasal patients. The articulatory parameters for compensatory articulation were optimized by minimizing the spectral differences (first four formants) between the compensated nasalized vowe...

Changes in Articulator Movement Variability During Phonemic Development: A Longitudinal Study

The present study explored articulator movement variability during voicing contrast acquisition. The purpose was to examine whether oral articulator movement trajectories associated with the production of voiced/voiceless bilabial phonemes in children became less variable over time. Jaw, lower lip, and upper lip movements were recorded longitudinally in six, 19 month-old children as they began producing the voiceless phoneme /p/. Displacement signals were time and amplitude normalized. The spatiotemporal index (A. Smith, L. Goffman, H. Zelaznik, S. Ying, & C. McGillem, 1995) was computed to examine the variability in movement trajectories across repeated productions of target utterances. Spatiotemporal variability of lip and jaw movements significantly decreased as children began producing the voiceless phoneme /p/. A significant negative correlation between the STI and the length of voice onset time (VOT) was also found in the voiceless productions in 4 of the 6 participants. Oral articulator movement variability is reduced in children across the stabilization of voicing contrast acquisition. Further, the relationship between VOT contrast production and movement variability suggests that a coordinate system between the oral and laryngeal articulators may be refined as children acquire the voicing contrast.

A Longitudinal Study of Speech Production in Swedish Children with Unilateral Cleft Lip and Palate and Two-stage Palatal Repair

To describe speech production longitudinally in a group of children with unilateral cleft lip and palate (UCLP). Twenty consecutive children with UCLP and nine age-matched children without clefts in a comparison group. A two-stage palatal repair procedure with soft palate closure at 6 months and hard palate repair at 3 to 4 years. Percent correct consonants (PCC), percent correct places (PCP), and percent correct manners (PCM) at 3, 5, and 7 years of age. Cleft speech errors at the same ages. Previously collected data on number of consonant tokens, consonant types, frequency of occurrence of places and manners of articulation at 18 months. PCC and PCP were significantly lower in the UCLP group than in the comparison group at all ages. Number of consonant types and frequency of occurrence of dental plosives at 18 months correlated significantly with PCC at age 3. A high frequency of velar plosives at 18 months correlated significantly with a high prevalence of retracted oral articulation (dental/alveolar to palatal or velar) at both 3 and 5 years of age. The UCLP group performed worse than the comparison group at all ages. A high occurrence of dental plosives as well as a high number of consonant types in babbling and first words seem to be good indicators for better consonant production in later speech. The same prevalence of retracted oral articulation as in previous studies is attributed to the surgical technique.

Naming Speed and Visual Search Deficits in Readers With Disabilities: Evidence From an Orthographically Regular Language (Italian)

The study examined rapid automatized naming (RAN) in 42 children with reading disabilities and 101 control children—all native speakers of Italian, a language with shallow orthography. Third-, 5th- and 6th-grade children were given a RAN test that required rapid naming of color, object, or digit matrices. A visual search test using the same stimulus material (but not requiring a verbal response) and an oral articulation test were also given. Readers with disabilities performed worse than controls on the RAN test. This effect was larger in higher grades than in lower ones. Readers with disabilities were also slower than controls in performing the visual search test. The pattern of results for the RAN test held constant when the visual search performance was partialed out by covariance analysis, indicating the independence of the 2 deficits. The 2 groups did not differ for articulation rate. Finally, analysis of the pattern of intercorrelations indicated that reading speed was most clearly related to RAN, particularly in the group with reading disabilities. The results extend observations of RAN effects on reading deficits to Italian, an orthographically shallow language.

There Are No Back Vowels: The Larygeal Articulator Model

AbstractAs an alternative to the high-low-front-back model of vowel specification, thelaryngeal articulator modelis proposed, based on a reinterpretation of how the vocal tract functions to produce laryngeal and pharyngeal sounds. Evidence drawn from numerous laryngoscopic studies demonstrates the scope of articulatory behaviours possible in the pharynx. For a broad sample of languages, lingual retraction is shown to accompany laryngeal/pharyngeal gestures, motivating the redistribution of vowel quality designations. The vocal tract is divided into two articulatory components: the laryngeal articulator and the oral articulator. The vowel chart is split into three sectors: front, raised, and retracted. Whereas front vowels can be qualified as close or open, so-called back vowels are re-designated as either raised or retracted, and the role of retraction as a function of the laryngeal constrictor mechanism is elaborated.

Rapid naming, not cancellation speed or articulation rate, predicts reading in an orthographically regular language (Italian)

This study examined the influence of rapid automatization naming (RAN) measures on various parameters of reading performance in children who were native speakers of a language with a shallow orthography (Italian). Participants included 281 children enrolled in first-to-sixth grade. They were given a Naming test, in which they had to name rapidly matrices of colors, objects, or digits, a Cancellation test, using the same stimulus materials, and an oral Articulation test. Performance on all tests improved steadily across ages tested. Performance on the Naming test, but not on the Cancellation and Articulation tests, predicted speed and accuracy in reading; none of these measures reliably predicted the reading comprehension measure. Data on a Blending test were also available for a subsample of first- and third-graders. Both RAN and phonological ability contributed independently to the prediction of reading ability (accuracy and speed) in these participants. The results extend observations on RAN to an orthographically shallow language (Italian) and suggest an element of continuity between languages with opaque and transparent orthographies.

There Are No Back Vowels: The Laryngeal Articulator Model

As an alternative to the high-low-front-backmodel of vowel specification, the laryngeal articulator model is proposed, based on a reinterpretation of how the vocal tract functions to produce laryngeal and pharyngeal sounds. Evidence drawn from numerous laryngoscopic studies demonstrates the scope of articulatory behaviours possible in the pharynx. For a broad sample of languages, lingual retraction is shown to accompany laryngeal/pharyngeal gestures, motivating the redistribution of vowel quality designations. The vocal tract is divided into two articulatory components: the laryngeal articulator and the oral articulator. The vowel chart is split into three sectors: front, raised, and retracted. Whereas front vowels can be qualified as close or open, so-called back vowels are re-designated as either raised or retracted, and the role of retraction as a function of the laryngeal constrictor mechanism is elaborated.

Development of functional synergies for speech motor coordination in childhood and adolescence.

Adults produce rapid, interleaved sequences of speech sounds by controlling the relative motions in time and space of the oral articulators. The control and coordination of these effectors appear to be automatic, effortless, and usually error free. If speech production is viewed within the framework of classical motor control theories, we can infer that adults have organized functional synergies (consistent patterns of activation of muscle collectives) that act as stable subunits. In this study, the development of these stable functional synergies is examined. Motion of the upper lip, lower lip, and jaw was recorded during sentence production in 180 children and adults (aged 4-22 years). Two indices of oral motor coordination were computed, which reflect the degree of trial-to-trial consistency in intereffector relationships and thus the stability of the underlying functional synergies. Major findings are: (a) The time course of development for speech motor coordination is protracted, (b) speech motor control processes are not adultlike until after age 14 years for both females and males, (c) boys (until age 5 years) show a slower maturational course of speech motor development, and (d) late childhood (the 7- to 12-year period) is characterized by a plateau in the development of these coordinative synergies for speech production. We posit that multiple factors are likely to contribute to the protracted development of oral motor coordination for speech, including maturation of components of the motor system itself and maturation of the brain subsystems for language processing.

Dysarthria: Tools for Clinical Decision-Making

Dysarthria: Tools for Clinical Decision-Making

An electronic database of Norwegian speech sounds: clinical aspects

The Electronic database of Norwegian speech sounds under development at the University of Oslo is intended to be a resource for phonetic research and practice. Beside its theoretical contribution as a research tool and as a basis for cross-linguistic comparison, one of the primary goals is for the database to be a tool that can assist in the treatment of speech and language impaired subjects with articulatory disorders. A number of registration techniques are used: the main techniques are simultaneous EPG and EMA recordings, registering oral passive and active articulation, respectively. This is complemented by measurements of vocal fold activity, intraoral air pressure, and nasal and oral emission of airflow. With the addition of the acoustic picture, provided by spectrography, all major aspects of speech production are covered and may be displayed in an explicit manner.

Common features of fluency-evoking conditions studied in stuttering subjects and controls: an [formula omitted] PET study

We used H 2 15 O PET to characterize the common features of two successful but markedly different fluency-evoking conditions — paced speech and singing — in order to identify brain mechanisms that enable fluent speech in people who stutter. To do so, we compared responses under fluency-evoking conditions with responses elicited by tasks that typically elicit dysfluent speech (quantifying the degree of stuttering and using this measure as a confounding covariate in our analyses). We evaluated task-related activations in both stuttering subjects and age- and gender-matched controls. Areas that were either uniquely activated during fluency-evoking conditions, or in which the magnitude of activation was significantly greater during fluency-evoking than dysfluency-evoking tasks included auditory association areas that process speech and voice and motor regions related to control of the larynx and oral articulators. This suggests that a common fluency-evoking mechanism might relate to more effective coupling of auditory and motor systems — that is, more efficient self-monitoring, allowing motor areas to more effectively modify speech. These effects were seen in both PWS and controls, suggesting that they are due to the sensorimotor or cognitive demands of the fluency-evoking tasks themselves. While responses seen in both groups were bilateral, however, the fluency-evoking tasks elicited more robust activation of auditory and motor regions within the left hemisphere of stuttering subjects, suggesting a role for the left hemisphere in compensatory processes that enable fluency. Educational objectives: The reader will learn about and be able to: (1) compare brain activation patterns under fluency- and dysfluency-evoking conditions in stuttering and control subjects; (2) appraise the common features, both central and peripheral, of fluency-evoking conditions; and (3) discuss ways in which neuroimaging methods can be used to understand the pathophysiology of stuttering.

Speed–curvature relations for speech-related articulatory movement

During speech production, oral articulator points exhibit spatially complex trajectories. This spatial complexity is partially reflected in the trajectory's curvature history (where curvature is defined as the rate of change of direction, parameterized for arc length). Informal observation of articulatory movement reveals that an increase in the degree of trajectory curvature is often associated with a slowing of the articulator. Such a relation between the speed and curvature of movement has been quantified for a variety of behaviors within the limb and oculomotor systems. This relation has been called the 1/3 power law. Such an association has not been quantified for speech movements. If speech movements adhere to the 1/3 power law, it would imply a specific constraint on the variability in spatial complexity (as reflected by curvature) and the time course of speech-related movements. This study empirically evaluated the relationship between articulator speed and trajectory curvature for speech-related mid-sagittal planar movements of the tongue, lower lip and mandible in a group of healthy speakers. Results revealed that movement speed and trajectory curvature are related by a power function whose exponent is near, but not exactly 1/3. Articulators exhibited systematic variations in the strength of association, and value of the exponent. These results suggest that speed and curvature of speech movement covary in ways similar to other motor systems.

Speech outcomes in isolated cleft palate: impact of cleft extent and additional malformations.

The purpose of the study was to study the speech outcome in a series of 5-year-old children born with an isolated cleft palate and compare the speech with that of noncleft children and to study the impact of cleft extent and additional malformation on the speech outcome. A cross-sectional retrospective study. A university hospital serving a population of 1.5 million inhabitants. Fifty-one patients with an isolated cleft palate; 22 of these had additional malformations. Thirteen noncleft children served as a reference group. A primary soft palate repair at a mean of 8 months of age and a hard palate closure at a mean age of 4 years and 2 months if the cleft extended into the hard palate. Perceptual judgment of seven speech variables assessed on a five-point scale by three experienced speech pathologists. The cleft palate group had significantly higher frequency of speech symptoms related to velopharyngeal function than the reference group. There were, however, no significant differences in speech outcome between the subgroup with a nonsyndromic cleft and the reference group. Cleft extent had a significant impact on the variable retracted oral articulation while the presence of additional malformations had a significant impact on several variables related to velopharyngeal function and articulation errors. Children with a cleft in the soft palate only, with no additional malformations, had satisfactory speech, while children with a cleft palate accompanied by additional malformations or as a part of a syndrome should be considered to be at risk for speech problems.

Articulatory and acoustic studies on domain-initial strengthening in Korean

This study examines the effect of prosodic position on segmental properties of Korean consonants /n, t, th, t*/ along the articulatory parameters peak linguopalatal contact and stop seal duration, and several acoustic parameters. These parameters were compared in initial position in different domains of the Korean prosodic hierarchy. The first result is that consonants initial in higher prosodic domains are articulatorily stronger than those in lower domains, in the sense of having more linguopalatal contact. Second, there is a strong correlation between linguopalatal contact and duration (both articulatory and acoustic), suggesting that “strengthening” and “lengthening” is a single effect in Korean. We interpret this relation as one of undershoot: in weaker positions, consonants are shorter and undershoot contact targets. The different consonant manners of Korean can be characterized as varying in both duration and contact in this way. Third, there is another, less consistent, kind of lengthening and strengthening specific to Korean, namely that tense and aspirated consonant oral articulations can be longer and stronger word-medially than word-initially. Fourth, the acoustic properties VOT, total voiceless interval, %voicing during closure, nasal energy minimum, and to a lesser extent stop burst energy and voicing into closure, were found to vary with prosodic position and, in some cases, to correlate with linguopalatal contact. They could thus potentially provide cues to listeners about prosodic structure.

On idiolectal differences in speaking rate: A comparison of spontaneous and read speech

Individuals who share a dialect nonetheless differ consistently in phonetic expression. The origin of such idiolectal differences has been sought in sociolinguistically and in physiologically motivated accounts. Our study focused on characteristic differences in the habitual rate of speech production within a dialect, aiming to calibrate the contribution of neuromuscular constraint in idiolect differences. We sampled and analyzed the temporal characteristics of spontaneous and read speech produced by a set of adolescent female talkers from Brooklyn, New York. Spontaneous speech was elicited by open-ended questions, while the Farm Script was used as the text for production of read speech at comfortable and at rapid rates. Overall, the rate of rapid read speech was correlated with the rate of comfortable spontaneous speech and comfortable reading, indicating a clear contribution of neuromuscular constraints to characteristic differences in speech rate. However, some talkers exhibiting the ability to produce rapid speech at the fastest rates adopted comfortable speaking rates at the slower end of the distribution. In light of these findings, we doubt that idiolectal differences in speaking rate can be accountable solely by appeal to differences between individuals in agility of oral articulators. [Work supported by NIH DC00308.]

A Comparison of Babbling and Speech at Pre-Speech Level, 3, and 5 Years of Age in Children with Cleft Lip and Palate Treated with Delayed Hard Palate Closure

Babbling and speech in 21 children with cleft palate were compared at pre-speech level, 3, and 5 years of age. The aims were to study if misarticulations in pre-school speech appear to be articulatorily related to the sound productions in pre-speech, whether the feeding technique influenced the prevalence of anterior articulation, and if there was a relationship between speech and the size of the residual cleft at 3 and 5 years of age. All the children had the soft palate closed, whereas the cleft in the hard palate was left open to be closed later on. Perceptual judgement of speech revealed a high prevalence of hypernasality, nasal escape and retracted oral articulation of dental or alveolar plosives. The latter was correlated with the size of the residual cleft area. There was a tendency towards a relationship between absence of anterior sound productions in babbling and retracted oral articulation in speech. The feeding technique, however, appeared not to have had any influence on articulatory place.

Speech outcome after cleft palate surgery with the Göteborg regimen including delayed hard palate closure.

The regimen for treatment of children with cleft lip and palate in Göteborg, Sweden, until 1996 included early soft palate repair at 6-8 months of age and delayed closure of the hard palate at about 8 years of age to improve maxillary growth. The aims of this report were to describe the treatment concept and to present speech data of 59 children treated by this method. The speech of 38 children with unilateral and 21 with bilateral cleft lip and palate was evaluated perceptually from standardised tape recordings of repeated sentences and spontaneous speech at five ages from 3 to 16 years of age. All patients were not evaluated at each age level. The results showed a low prevalence of hypernasality after hard palate closure and pharyngeal flap surgery in only five children (8%), indicating a primary velopharyngeal insufficiency in less than 10% of the children. Only three children with bilateral clefts had glottal articulation when at pre-school age and no child with a unilateral cleft did. These results were interpreted as an indication of velopharyngeal competence (VPC) in most of the children. In addition, the speech problem found in these children consisted of retracted oral articulation of alveo-dental pressure plosives, which is almost always an indicator of VPC. However, we do consider that retracted oral articulation is a problem and to improve our results further we have decided to modify the technique for soft palate closure slightly and place the vomer flap further anteriorly to encourage narrowing of the cleft in the hard palate, and to close the hard palate at 3 years of age.

Articulatory organization of mandibular, labial, and velar movements during speech.

It has been shown that articulator movements during speech are adjusted along a number of spatiotemporal dimensions. For example, variations in the extent of lip, jaw, or tongue motion are associated with proportional changes in the respective articulators' peak velocity. Modifications in the timing of lip and jaw actions are apparently constrained, exhibiting relative timing covariation. Syllable prominence systematically affects some combination of the articular motion parameters, i.e., extent, speed, and duration. The present investigation is an attempt to extend observations of the spatiotemporal properties of articulator movement to include the velum. Lip, jaw, and velar kinematics were recorded optoelectronically and simultaneously with the acoustic signal during productions of the utterance/mabnab/. The spatial and temporal relations between the lips, the jaw, and the velum were examined and compared across articulators. For movements associated with each syllable, the velum displayed scaling pattern qualitatively similar to those of the lips and jaw. Moreover, velocity-displacement relations were more robust for the lowering than for the raising movements of the velum. There was evidence of interarticulator coupling between the velum and the jaw, and between the velum and the upper lip, although this coupling was not as strong as that observed among the oral articulators. Articulator specific differences in velocity-displacement correlations and degree of interarticulator cohesion for the various movement phases may be related to a combination of aerodynamic and phonetic factors, such as the phonologically noncontrastive nature of nasalization in English.

Time-dependent oral articulator responses to jaw perturbation

It is an established notion that the actions of the articulators are functionally constrained during speech production. Articulator tasks toward attainment of a specific goal appear to be distributed to the structures involved. This implies a global organization of the speech motor control mechanism. The present kinematic study examines the time dependence of articulator responses to jaw perturbation. Jaw-lowering perturbations were applied randomly during speech with the use of a mandibular prosthesis. Following the perturbation the coordinative timing among the articulators was generally maintained. It appears that the responses of the articulators to perturbations of the jaw were differentially affected by the time of the load application of the jaw and appeared to depend on the temporal relation between the onset of the perturbation and the onset of the component speech event. These load-induced modifications were effected in a manner such that the adjustments performed to counterbalance the perturbation and attain the specified target (/b/ production) were carried out in a modulated way. The jaw was the major contributor of compensatory adjustments to its mechanical perturbation, while the lower lip and upper lip supplemented these modifications in an almost reciprocal manner. Of the articulator kinematic variables (displacement, velocity, and duration), velocity was most sensitive to the temporal onset of the perturbation. [Work supported by NIH Grant Nos. DC-00121 and DC-00594 to Haskins Laboratories.]