Tongue Body Research Articles

Cranio-facial remodeling in domestic dogs is associated with changes in larynx position.

The hyo-laryngeal complex is a multi-segmented structure integrating the oral and pharyngeal cavities and thus a variety of critical functions related to airway control, feeding, and vocal communication. Currently, we lack a complete understanding of how the hyoid complex, and the functions it mediates, can also be affected by changes in surrounding cranio-facial dimensions. Here, we explore these relationships in a breed of domestic dog, the Portuguese Water Dog, which is characterized by strong cranio-facial variation. We used radiographic images of the upper body and head of 55 adult males and 51 adult females to obtain detailed measures of cranio-facial variation and hyoid anatomy. Principal components analysis revealed multiple orthogonal dimensions of cranio-facial variation, some of which were associated with significant differences in larynx position: the larynx occupied a more descended position in individuals with shorter, broader faces than in those with longer, narrower faces. We then tested the possibility that caudal displacement of the larynx in brachycephalic individuals might reflect a degree of tongue crowding resulting from facial shortening and reduction of oral and pharyngeal spaces. A cadaver sample was used to obtain detailed measurements of constituent bones of the hyoid skeleton and of the tongue body, and their relationships to cranio-facial size and shape and overall body size supported the tongue-crowding hypothesis. Considering the presence of descended larynges in numerous mammalian taxa, our findings establish an important precedent for the possibility that laryngeal descent can be initiated, and even sustained, in part in response to remodeling of the face and cranium for selective pressures unrelated to vocal production. These integrated changes could also have been involved in hominin evolution, where the different laryngeal positions in modern humans compared with nonhuman primates have been traditionally linked to the evolution of speech but which are likely to be multifactorial.

Tissue distribution of deoxynivalenol in piglets following intravenous administration

Contamination of deoxynivalenol (DON) in grains is common worldwide and pigs are particularly susceptible to this mycotoxin. The distribution of DON in porcine tissues following intravenous administration was investigated in this study. Fifteen pigs were randomly divided into three groups. Animals in groups A and B were administrated with DON at the dose of 250 and 750 µg kg−1 body weight, respectively, while group C served as blank control. Plasma, bile and 27 tissues were collected at 30 min post-administration. DON concentrations in all samples were tested using high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). To observe the distribution of DON in tissues, these samples were further subjected to the immunohistochemical analyses. Totally, the bile and 13 tissues were sampled for DON-based detection, including kidney, mesenteric lymph nodes, muscle, stomach, jejunum, colon, plasma, spleen, rectum, cecum, liver, ileum, and duodenum. No significant difference was observed for the concentrations of DON in duodenum, ileum and liver samples between groups A and B; while the DON concentrations in cecum and rectum of group B were significantly higher (P-value <0.05) than those in group A. In addition, the DON concentrations in stomach, jejunum, colon, mesenteric lymph nodes, muscle, kidney, spleen, bile, and plasma of group B were remarkably higher than those of group A (P-value<0.01). Levels of DON in other 14 tissues including medulla oblongata, midbrain, diencephalon, pons, tip and tongue body, tongue, soft palate, tonsils, pharyngeal mucosa, oral buccal mucosa, thymus, thyroid, esophagus and adrenal gland were all below the limit of detection. The results of immunohistochemistry showed that 11 tissue samples (medullaoblongata, tonsil, adrenal medulla, thyroid gland, thyroid, stomach, duodenum, jejunum, kidney, spleen, and mesenteric lymph nodes) were positive and DON was mainly distributed around blood vessels in these tissues. Therefore, we believed that concentrations of DON in tissues differ when pigs are in exposure to various dosages and DON causes lesions in many pig tissues.

Using ultrasound articulatory signals to investigate the phonetic motivations of English /æ/ tensing

A common simplifying technique in ultrasound studies of variation is to select a single representative frame for each token, sacrificing dynamic information that is often critical for understanding the phonetic motivations of phonological phenomena. We examine the phonetic motivations for tongue body raising in English /æ/ tensing (e.g., Labov et al. 2005) in 23 North American English speakers using phonetically meaningful time-varying articulatory signals extracted directly from ultrasound video. An articulatory measure of /æ/ tenseness is generated using regression to find the linear combination of articulatory principal components (found using EigenTongue Feature Extraction; Hueber et al. 2007) that best accounts for the F2-F1 difference in front vowels. We have previously shown (Carignan et al. 2015) that tensing before /m n/ involves tongue body raising that is timed to the vowel nucleus, whereas tensing before /ɡ ŋ/ involves anticipating the velar closure to different degrees in different dialects. Here, we examine the phonetic motivations for this /æ/ tensing. An articulatory measure of velar fronting shows increased /ɡ/ fronting in speakers who tense /æ/ before /ɡ/, and a purely lingual analog of F1 shows that the effect of nasalization on F1 is much smaller than the phonological effect of pre-nasal /æ/ tensing.

An acoustic study of coarticulatory resistance in “dark” and “light” alveolar laterals

This study reports on the results of an acoustic investigation on the effects of contextual vowels on alveolar laterals in two languages, Spanish and Catalan. In particular, two contact varieties of these languages, those spoken on the island of Majorca, are compared. Catalan /l/ has been described as “dark” and Spanish /l/ as “light” or “clear,” and these characterizations have been confirmed with acoustic and articulatory data. Furthermore, it has been suggested that pharyngealization (or velarization) degree in the laterals affects their degree of coarticulatory resistance, with pharyngealized laterals being more resistant to coarticulation than non-pharyngealized ones. This is attributed to tighter articulatory control of the tongue body in pharyngealized than non-pharyngealized laterals. This study tests this hypothesis with acoustic data from 10 (Majorcan) Catalan and 10 (Majorcan) Spanish male speakers, and it shows that coarticulatory resistance is indeed modulated by the degree of pharyngealization of the laterals. Importantly, in addition to finding a difference in coarticulatory resistance between the two language varieties, the study finds that by-speaker average pharyngealization in the laterals is a significant linear predictor of by-speaker coarticulatory resistance in these sounds.

Robust tongue segmentation by fusing region-based and edge-based approaches

A tongue diagnosis system can offer significant information for health condition. To ensure the feasibility and reliability of tongue diagnosis, a robust and accurate tongue segmentation method is a prerequisite. However, both of the common segmentation methods (edge-based or region-based) have respective limitations so that satisfactory results especially for medical use are often out of reach. In this paper, we proposed a robust tongue segmentation method by fusing region-based and edge-based approaches. Before segmentation, ROI (region of interest), which will be used as input for the subsequent segmentation, was extracted by a novel way. Next, we merged adjacent regions utilizing the histogram-based color similarity criterion to get a rough tongue contour. It is essentially a region-based method and hence the results are less sensitive to cracks and fissures on surface of the tongue. Then, we adopted a fast marching method to connect four detected reliable points together to get a close curve, which is based on edge features. Contour obtained by region-based approach was utilized to act as a mask during fast marching process (edge-based) and the mask added limits so that the ultimate contour will be more robust. Qualitative and quantitative comparisons show that the proposed method is superior to the other methods for the segmentation of tongue body in terms of robustness and accuracy.

Mandibular lingual release versus mandibular lip-split approach for expanded resection of middle–late tongue cancer: A case-control study

ObjectiveThe mandibular lingual release (MLR) and mandibular lip-split (MS) approaches are the two common access approaches for resection of malignant tongue tumors. This case-control study aimed to evaluate the effectiveness and safety of these two approaches for the expanded resection of middle–late tongue cancer. Material and methodsA total of 56 matched patients with resectable middle–late squamous cell carcinoma of the tongue body were consecutively hospitalized for expanded resection using the MLR (n = 26) or MS approach (n = 30) between March 2004 and November 2012. Main outcome measures consisted of tumor exposure, surgical morbidity, maxillofacial motor–sensory return, and head/neck-specific quality of life. ResultsThe two approaches achieved similar en bloc R0 resection with similar tumor exposure. The MLR approach was associated with a significantly lower frequency of maxillofacial pain (P < 0.05) and no incidence of mandible nonunion. The MLR approach was also associated with a significantly better quality of life with respect to local pain, facial appearance, and mood. ConclusionCompared to the MS approach, the MLR approach was associated with significantly less surgical morbidity and a significantly better quality of life for middle–late tongue cancer patients undergoing expanded resection.

A kinematic analysis of Japanese /r/: Effects of syllable position and vowel context

Japanese /r/ is claimed to vary substantially as a function of context. Greater stricture is thought to occur after pauses and at initial syllable position when compared with intervocalic position. The environment of certain vowels is thought to result in changes to the degree of lateralization of /r/. However, few studies have investigated the articulatory processes involved in realizing the varieties of Japanese /r/ production. To address this issue, we obtained speech recordings for ten native talkers of standard Japanese using an Electromagnetic Articulography (EMA) system. Each talker produced 12 repetitions of /ra/, /ri/, /ru/, /re/, /ro/ in a carrier phrase designed to contrast syllable boundaries: /sore wa VCV VCV desu # CV/ (e.g., “This is ara ara [pause] ra”). Kinematic data were recorded with sensors placed on the tongue tip (TT), tongue body (TB), tongue left lateral (TL), tongue right lateral (TR), and lower lip (LL) positions. Results to date suggest syllable-initial (post-pausal) /r/ has th...

Articulation of vowel height in Taiwanese Vowels: An EMA study

Whalen et al.’s (2010) ultrasound study has suggested that constriction degree “may be the best descriptor for height” in American English front vowels {i, ɪ, e, ɛ}. The present study took a further step, investigating the case of height and backness distinction in Taiwanese front and back vowels. Stimuli consisted in /CV/ sequences with V corresponding to one of the six vowels {i, e, a, ɔ, ɣ, u} (Southern variety). Five adult speakers were asked to repeat each sequence six times in random order. The articulatory data were collected using the Carstens AG500 EMA system. Our results show that vowel height and backness in Taiwanese vowels can be reliably differentiated as follows: (1) for front and central vowels, height is primarily distinguished by Tongue Body Constriction Degree (TBCD) (i>e>a) (less robustly by Tongue Tip Constriction Degree), whereas height distinction of back vowels is made in Tongue Dorsum Constriction Degree (TDCD) (u>ɣ>ɔ), (2) backness can be distinguished by Tongue Tip and Tongue Body Constriction Location. Therefore, Whalen et al.’s (2010) claim can be extended to back vowels as well (at least in Taiwanese). Furthermore, our results are compatible with Ladefoged’s (2001) “holistic” view of vowel height as long as his “highest point of the tongue” can be “locally” interpreted: TBCD for height of front and central vowels and TDCD for back vowels. In sum, the present study suggests that distinction in vowel height be relativized to different gestural constriction degree.

Korean /l/-flapping in an /i/-/i/ context

In this study, we aim to describe kinematic characteristics of Korean /l/-flapping in two speech rates (fast vs. comfortable). Production data was collected from seven native speakers of Seoul Korean (four females and three males) using electromagnetic midsagittal articulometry (EMMA), which provided two dimensional data on the x-y plane. We examined kinematic properties of the vertical/horizontal tongue tip gesture, the vertical/horizontal (rear) tongue body gesture, and the jaw gesture in an /i/-/i/ context. Gestural landmarks of the vertical tongue tip gesture are directly measured. This serves as the actual anchoring time points to which relevant measures of other trajectories referred. The study focuses on velocity profiles, closing/opening spatiotemporal properties, constriction duration, and constriction minima were analyzed. The results are summarized as follows. First, gradiently distributed spatiotemporal values of the vertical tongue tip gesture were on a continuum. This shows more of a reduction in fast speech rate, but no single instance of categorical reduction (deletion). Second, Korean /l/-flapping predominantly exhibited a backward sliding tongue tip movement, in 83% of production, which is apparently distinguished from forward sliding movement in English. Lastly, there was an indication of vocalic reduction in fast rate, truncating spatial displacement of the jaw and the tongue body, although we did not observe positional variations with speech rate. The present study shows that Korean /l/-flapping is characterized by mixed articulatory properties with respect to flapping sounds of other languages such as English and Xiangxiang Chinese. Korean /l/ flapping demonstrates a language-universal property, such as the gradient nature of its flapping sounds that is compatible with other languages. On the other hand, Korean /l/-flapping also shows a language-particular property, particularly distinguished from English, in that a backward gliding movement occurs during the tongue tip closing movement. Although, there was no vocalic reduction in V2 observed in terms of jaw and tongue body height, spatial displacement of these articulators still suggests truncation in fast speech rate.

The role of individual dental stent on taste protection in the patients with primary nasopharyngeal carcinoma treated with radiotherapy

Objective To investigate the role of individual dental stent on taste protection in the patients with primary nasopharyngeal carcinoma. Methods Firstly, dosimetric evaluation of the tongue under the circumstance of 10 pairs of patient wearing dental stent or not was done. Secondly, a total of 61 patients were randomized into two arms: 29 were in the trial arm and 32 in the control arm. The patients wore dental stent during radiotherapy in trial group, but not in control group. The endpoint was taste dysfunction before radiotherapy, every week during radiotherapy till the completion of radiotherapy, and followed up six months after radiotherapy. Results The mean dose of tip of tongue, body of tongue, base of tongue for patient with dental stent or not were (394.43±24.01) cGy, (986.35±77.15) cGy, (4 401.16±179.01) cGy and (677.03±110.05) cGy, (2 418.19±414.18) cGy, (4 878.67±387.45) cGy (P value were 0.031, 0.007 and 0.284, respectively) separately. By the completion of the radiotherapy, there were 9 (31.03 %) patients suffering from a taste dysfunction in the trial group and 25 (78.13 %) in the control group (P<0.001). Conclusions Individual dental stent has a potential tendency to relieve the taste impairment by reducing the irradiation dose of tongue. Key words: Nasopharyngeal carcinoma; Radiotherapy; Dental stent; Side effects; Taste dysfunction

An articulatory model of standard Chinese using MRI and X-ray movie

To better understand speech production from the phonological inputs to articulatory movements and then to acoustic outputs, it is important to establish an elaborate articulatory model of the vocal tract. This paper has explored the articulatory mechanism of speech production in Standard Chinese and developed a geometric articulatory model in both the visual and acoustic modalities. This model was based on the data of MRI images and X-ray movie, with the former providing detailed volumetric information of the vocal tract, and the latter the dynamic information of articulation. In this model, the seven articulators have been studied and modeled, including the hard palate, pharynx, jaw, lips, velum, tongue, and larynx. The tongue is modeled as two parts: tongue tip and tongue body, thus reducing the necessary number of parameters. The relation between larynx height and fundamental frequency in regard to the four tones is also modeled. These two improvements on tongue and larynx modeling have contributed new ideas to the articulatory modeling of Standard Chinese. This model can serve as a research tool for linguists, phoneticians, and speech engineers, and can be used in parameter speech synthesis, virtual speaker, and visual assistant speech training of Standard Chinese. 提要: 爲了更好地理解言語的產生過程,即如何從音位輸入到調音器官的動 作、再到聲學輸出,需要建立詳盡的聲道調音模型。本文是對漢語普 通話言語產生中調音機制的探索與研究,建立了一個具有視覺和聲學 輸出的幾何調音模型。該調音模型的數據源自於聲道的磁共振圖像和 X 光錄影,前者主要提供聲道的立體形狀,後者提供調音的動態過程。 在這個模型中,聲道被分解為七個調音部位進行研究:硬齶、喉腔後 壁、下頜、雙唇、軟齶、舌頭和喉管。其中創新性地,舌頭又被分為 舌體(相對簡單)和舌尖(更為靈活)兩部份,從而簡化所需要的參 數;另外,普通話四聲中基頻高低與喉管上下高度的關係也加入到模 型中。該模型可以作為研究工具服務於語言學、語音學和言語工程, 並可用於語音參數合成、虛擬說話人、普通話輔助教學等領域。

Tongue Dynamics in Childhood Apraxia of Speech: A Case Study

Childhood Apraxia of Speech (CAS) is a subtype of speech sound disorder with unique features that include deficits in speech sound accuracy, prosody, coarticulatory transitions, and consistency on repeated attempts. Articulatory errors are abundant in apraxia such as articulatory groping, perseverative errors, and speech initiation difficulties. There are few studies conducted to see the articulatory pattern of CAS. Present study aimed to analyse the prime articulator, i.e. tongue dynamics in CAS in different place of articulation comparing with typically developing children. One child with CAS and one typically developing age matched control subject were participated in the study. The test material consisted of three meaningful words consisting stops in three different places of articulation including dental /t?/, retroflex/?/ and velar /k/. The instrument Mindray ultrasound 6600 with Articulate Assistant Advanced (AAA) ultrasound module Version 2.14 was used for data collection and analysis. The overall results showed variation across trials in CAS and this disparity between the trails were less in typical speaker’s utterances compared to CAS. The placement of tongue was diverse across subject during the articulation of /k/ with respect to the tongue height and advancement. Variations were more evident in the tongue front and posterior tongue body region compared to anterior tongue body. In the case of retroflex stop /?/ tongue front and posterior tongue body image was not prominent in all repetition of CAS. But in normal speaker all the three divisions were prominent and variations across trails were less. This information can be useful to set the treatment plans for CAS to resolve the articulatory errors.

Weighted Nuclear Norm Minimization Based Tongue Specular Reflection Removal

In computational tongue diagnosis, specular reflection is generally inevitable in tongue image acquisition, which has adverse impact on the feature extraction and tends to degrade the diagnosis performance. In this paper, we proposed a two-stage (i.e., the detection and inpainting pipeline) approach to address this issue: (i) by considering both highlight reflection and subreflection areas, a superpixel-based segmentation method was adopted for the detection of the specular reflection areas; (ii) by extending the weighted nuclear norm minimization (WNNM) model, a nonlocal inpainting method is proposed for specular reflection removal. Experimental results on synthetic and real images show that the proposed method is accurate in detecting the specular reflection areas and is effective in restoring tongue image with more natural texture information of tongue body.

Descrição dos gestos articulatórios envolvidos na produção dos sons /r/ e /l/

Objetivo Investigar os dados de natureza articulatória de consoantes líquidas e a coarticulação dessas consoantes diante da produção de diferentes contextos vocálicos, em adultos falantes típicos do Português Brasileiro (PB). Métodos Participaram da pesquisa cinco adultos com idades entre 25 e 37 anos. Os gestos articulatórios foram capturados pelo ultrassom Modelo DP-6600 e analisados por meio do software AAA (Articulate Assistant Advanced). Foram selecionados três pares de palavras com os sons /r/ e /l/, em Onset Medial, em diferentes contextos vocálicos: /a/, /i/, /u/. Todas as palavras foram representadas por figuras, incluídas em uma mesma frase veículo. As imagens dos gestos articulatórios visualizadas no ultrassom corresponderam aos frames relativos à elevação máxima da ponta da língua nas produções de /r/ e /l/. Resultados /r/ e /l/ apresentaram dois gestos simultâneos: ponta e corpo da língua. A vogal /i/, em contexto seguinte ao /r/, e a vogal /u/, em contexto seguinte ao /l/, proporcionaram maior grau de constrição da ponta e do corpo da língua, respectivamente. Conclusão Os segmentos pesquisados apresentaram duplos gestos de língua. A coordenação dos gestos de /r/ e /l/, associados aos diferentes contextos vocálicos, revelou diferentes configurações.

Dorsal Surface of the Tongue of the Hazel Dormouse Muscardinus Avellanarius: Scanning Electron and Light Microscopic Studies/ Grzbietowa Powierzchnia Języka Orzesznicy Muscardinus Avellanarius: Badania Z Wykorzystaniem Mikroskopu Skaningowego I Świetlnego

Abstract The dorsal surface of a hazel dormouse tongue was examined by scanning electron and light microscopy. The tongue of the hazel dormouse is elongated and widened in the proximal part. On the proximal one-third of the tongue a clear median groove is observed. The dorsal lingual surface was covered with five types of papillae: filiform, conical, fungiform, vallate and foliate. The arrangement, shape, size and direction of the filiform papillae vary depending on the region of the tongue. On the proximal part of the tongue, the filiform papillae are saw-like and tilted medioposteriorly, while on the distal part they have a fork-like shape and form a radial pattern with their processes oriented towards the center of the tongue. Fungiform papillae with single taste buds are evenly scattered on the anterior and middle part of the tongue body. On the root of the tongue, three star-like shaped vallate papillae are arranged in the form of a triangle and surrounded by conical papillae. A pair of foliate papillae are found on both edges of the posterior area of the tongue, forming three parallel folds separated by deep grooves. The dorsal surfaces of the vallate and foliate papillae are covered with hard-cornified epithelium, while the lateral surfaces have noncornified epithelium with numerous taste buds. The results of our studies show that the tongue structure of the hazel dormouse is more primitive in comparison with other rodents which is related to their phylogeny and feeding habits.

Investigation of the role of the tongue root in Kazakh vowel production using ultrasound

It has been argued that Kazakh primarily distinguishes its anterior ("front") vowels from its posterior ("back") vowels through retraction of the tongue root. This analysis is at odds with the traditional assumption that the anteriority of Kazakh vowels is contrasted by tongue body position. The present study uses ultrasound imaging to investigate the extent to which the position of the tongue root and the tongue body are involved in the anteriority contrast in Kazakh. Native speakers of Kazakh were recorded reading words (in carrier sentences) containing target vowels, which were controlled for adjacent consonants and metrical position. An audio recording was also made of these sessions. Frames containing productions of the target vowels were extracted from the ultrasound video and the imaged surface of the tongue was manually traced. Analyses of tongue root and body position were analyzed for each vowel and will be presented together with formant measurements from the audio recordings.

An articulatory study of high vowels in Mandarin produced by native and non-native speakers

This paper examined the articulatory properties of high vowels [i], [y], and [u] in Mandarin produced by four Taiwanese Mandarin native speakers and four English-speaking Chinese learners (L2 learners) with an Electromagnetic Articulagroph AG500. The articulatory positions of the tongue top (TT), the tongue body (TB), the tongue dorsal (TD), and the lips were investigated. The TT, TB, and TD of [y] produced by the L2 learner were further back than that by the native. In addition, the TD of [y] by the L2 learners was higher than the native. Further comparison found that the tongue positions of [y] was similar to [u] in L2 production. Regarding to the lip positions, the [y] and [u] were more protruded that [i] in the native production, while there is no difference among these three vowels in the L2 production. The findings suggested that most of the L2 learner were not aware that the lingual target [y] should be very similar to [i] but the lip articulators of [y] are more protruded than [i]. Some L2 learners pronounce [y] more like a diphthong [iu] rather than a monophthong.

Tongue papillae morphology of brown-throated sloth Bradypus variegatus (SCHINZ, 1825)

The Bradypusvariegatus inhabits the forests of South America and feeds from leaves, branches and sprouts from different plants. Due to its diet and the lack of literature on the morphological aspect of Xenarthras, five Bradypusvariegatus tongues from animals which died from natural causes were evaluated, and they came from Pará State Museum Emílio Goeldi and were donated to the Laboratory of Animal Morphological Research (LaPMA) from UFRA, for revealing the different types of papillae and epithelial-connective tissue. Macroscopically, the tongues presented elongated shape, rounded apex, body, root, median sulcus in the root's apex, and two vallate papillae. The mucous membrane of the tongue revealed a keratinized stratified pavement epithelium, while the ventral surface of the tongue was thin and smooth, not provided with any type of papillae. However, the dorsal surface of the tongue was irregular with the presence of three types of papillae: filiform, fungiform and vallate papillae. The filiform papillae found were of a simple type, presenting a rounded base, irregularly distributed with a larger concentration and development on the tongue's apex and body. The fungiform papilla showed a practically smooth surface with irregular format, with the presence of gustatory pores; these were found all over the dorsal surface, with larger concentration at the rostral part of the apex. Only two vallate papillae were observed disposed in the root of the tongue, surrounded by a deep groove, and revealing several taste buds. The tongues from Bradypusvariegatus presented gustatory papillae similar to the ones described for other Xenarthras species and wild mammals.

Tongue motion characteristics during vowel production in older children and adults

This study examined tongue movements in consonant-vowel-consonant sequences drawn from real words in phrases as produced by 36 older children (three male and three female talkers at each age from 10 to 15 years) and 36 adults. Movements of four points on the tongue were tracked at 400 Hz using the Wave Electromagnetic Speech Research System (NDI, Waterloo, ON, CA). The four points were tongue tip (TT; 1 cm from tip on midline), tongue body (TB; 3 cm from tip on midline), tongue right (TR; 2 cm from tip on right lateral edge), and tongue left (TR; 2 cm from tip on left lateral edge). The phrases produced included the vowels /i/, /I/, /ae/, and /u/ in words (i.e., “see,” sit,” cat,” and “zoo”). Movement measures included 3D distance, peak and average speed, and duration of vowel opening and closing strokes. The horizontal curvature of the tongue was calculated at the trajectory speed minimum associated with the vowel production using a least-squares quadratic fit of the TR, TB, and TL positional coordinates. Symmetry of TR and TL vertical position was also calculated. Within-group comparisons were made between vowels and between-group comparisons were made between children and adults.

A physical figure model of tongue muscles

To help understanding tongue shape and motions, a physical figure model of tongue muscles using viscoelastic material of urethane rubber gel were made by improving previous models. Compare to previous shape tongue models that had been made and presented, the new model is constructed from tongue body (consisting of Transversus linguae, Verticalis linguae, Longitudinalis linguae superior, and Longitudinalis linguae inferior), and individual extrinsic tongue muscles (consisting of Genioglossus anterior, Genio glossus posterior, Hyoglossus, Styloglossus, and Palatoglossus) parts. Therefore, each muscle’s shape, starting and ending points, and relation to other muscles and organs inside mouth are more understandable than previous ones. As the model is made from viscoelastic material similar to human skin, reshaping and moving tongue are possible by pulling or pushing some parts of the tongue muscle by hand, that is, tongue shape and motion simulations by hand can be done. The proposed model is useful for speech science education or a future speaking robot using realistic speech mechanism.