Rotation and Translation of the Jaw During Speech

1990 ◽  
Vol 33 (3) ◽  
pp. 550-562 ◽  
Author(s):  
Jan Edwards ◽  
Katherine S. Harris

A two-dimensional rigid-body model of jaw movement was used to describe jaw opening and closing gestures for vowels and for bilabial and alveolar consonants. Jaw movements were decomposed into three components: (a) rotation about the terminal hinge axis, (b) the horizontal translation of that axis, and (c) the vertical translation of that axis. Data were collected for 3 subjects in two separate recording sessions. Multiple regression analysis was used to examine the relationships among the three jaw movement components. For 2 subjects, but not for the third, an interdependence between jaw rotation and the first principal component of jaw translation, horizontal translation, was observed. For these 2 subjects, the first degree of freedom of jaw movement corresponded to a combination of rotation and the first principal component of jaw translation. For the third subject, the first degree of freedom of jaw movement corresponded to rotation alone. The results of this study, like those of Westbury (1988), indicate that an accurate description of jaw movement during speech requires the recording of two points of jaw movement.

2010 ◽  
Vol 89 (4) ◽  
pp. 395-399 ◽  
Author(s):  
P.F Sowman ◽  
R.S.A. Brinkworth ◽  
K.S. Türker

Current knowledge regarding the sensitivity of the teeth to forces is based on psychophysical experiments that measured touch detection thresholds under static jaw conditions. It is not known whether jaw movements alter the perception of forces applied to the teeth, but, based on limb movement studies, it is hypothesized that the perception of mechanoreceptor outputs will be downwardly modulated by jaw movements. We predicted that, compared with static jaw conditions, rhythmic jaw movements would be associated with significantly higher psychophysical thresholds for the detection of incisally applied forces. In eight participants, mechanical pulses were delivered to an incisor during static jaw holding or during cyclic jaw opening and closing. Analogous to findings in human limbs, the psychophysical salience of periodontal mechanoreceptor feedback was downwardly modulated by physiologically relevant movements; detection thresholds for mechanical pulses applied to a central incisor were significantly higher during jaw-closing movements than during static jaw positioning.


1995 ◽  
Vol 80 (3_suppl) ◽  
pp. 1108-1112 ◽  
Author(s):  
Anne Bauer ◽  
Lutz Jäncke ◽  
Karl Theodor Kalveram

12 subjects uttered the testword /papapas/ repeatedly with three different speech rates and two stress patterns. On 17% randomly chosen trials, a mechanical load was applied unpredictably to the jaw in the direction of the opening movement. Load onset was triggered by the start of the first phonation. Analysis showed that the opening and closing displacements of the jaw movement in the first syllable were not influenced significantly by the perturbation. The load application prolonged the duration of the jaw movement in unstressed syllables but not in stressed syllables. Further, the mechanical perturbation of the jaw led to increased duration of phonation in unstressed syllables only, the effect for duration of phonation being greater at higher speech rates. These results demonstrate a coupling between articulation and phonation.


1999 ◽  
Vol 78 (10) ◽  
pp. 1662-1668 ◽  
Author(s):  
K. Yashiro ◽  
T. Yamauchi ◽  
M. Fujii ◽  
K. Takada

Human limb movements are successfully modeled based on the assumption that the central nervous system controls the movements by maximizing movement smoothness. Movement smoothness is quantified by means of a time integral of squared jerk (jerk-cost), where jerk is defined as the rate of change in acceleration. This study was performed to investigate whether the control of human masticatory vertical jaw movements can also be explained by a minimum-jerk (maximum-smoothness) model. Based on the assumption that minimum-jerk models account for vertical jaw-opening and -closing movements during chewing, the actual time profile of the movement trajectory was simulated by the model. The simulated jerk-costs and peak velocities were compared with those obtained by actual measurements of jaw movements during chewing. Jerk-costs and peak velocities of the jaw movements during chewing were significantly correlated with those predicted by minimum-jerk models (P < 0.0001, r between 0.596 and 0.799). The minimum-jerk models predicted closing movement trajectories more accurately than opening movement trajectories (jaw opening, root-mean-square error = 1.19 mm; jaw closing, 0.52 mm, t = 4.375, P < 0.0001). The results indicated that the vertical jaw movement control during chewing was represented by the minimum-jerk control model and that the vertical jaw-closing movement is smoother than the opening movement during gum-chewing.


1986 ◽  
Vol 55 (2) ◽  
pp. 301-319 ◽  
Author(s):  
R. W. Lambert ◽  
L. J. Goldberg ◽  
S. H. Chandler

Vertical and horizontal movements of the lower jaw (mandible) of ketamine-anesthetized guinea pigs were recorded in association with electromyographic (EMG) activity in the anterior digastric, lateral pterygoid, medial pterygoid, and deep masseter muscles during spontaneously occurring rhythmic jaw movements (SRJMs) and during rhythmical jaw movements induced by the intravenous administration of apomorphine (ARJMs). Both ARJMs and SRJMs were near periodic and occurred at frequencies in the 2- to 5-Hz range. However, the profiles of the mandibular movements and associated patterns of jaw muscle EMG activity differed dramatically for SRJMs versus ARJMs. SRJMs were characterized by prominent lateral excursions of the mandible that occurred in association with both the jaw opening and closing movements. The lateral excursions were directed to the left side on some SRJM cycles and to the right side on others. The direction of the lateral component alternated irregularly, but no more than three consecutive cycles with horizontal movements to the same side were observed at any time. Each SRJM cycle was generated by the occurrence of one of two coordinated sequences of EMG activity. One sequence produced right-sided cycles, the other produced left-sided cycles. Each sequence was initiated by an EMG burst in the digastric muscle ipsilateral to the direction of the horizontal excursion of the mandible, followed by EMG bursts in the contralateral digastric, lateral pterygoid, and medial pterygoid muscles. The EMG bursts in the digastrics and contralateral lateral pterygoid muscles were associated with jaw opening and the initial stage of lateral movement. EMG activity in the contralateral medial pterygoid muscle was associated with the onset of closing and a second stage of lateral movement. Masseter muscle activity was also observed during SRJMs, but only in a subset of the animals tested (3 of 12). When present, the masseter activity began well after the onset of jaw closing. No significant horizontal mandibular movements were observed during ARJMs. The mandibular trajectories during opening and closing always remained close to the midline. The opening phase of ARJM cycles was associated with bilaterally synchronized activity in the digastric and lateral pterygoid muscles. The closing phase was associated with bilaterally symmetric activity in the masseter muscles. The medial pterygoid muscles displayed little or no EMG activity during ARJMs. The durations of the EMG bursts recorded in the masseter muscle were correlated with cycle time during SRJMs, as were the burst durations of the digastric and lateral pterygoid muscles during ARJMs.(ABSTRACT TRUNCATED AT 400 WORDS)


2004 ◽  
Vol 16 (6) ◽  
pp. 579-586 ◽  
Author(s):  
Akihisa Okino ◽  
◽  
Hideaki Takanobu ◽  
Atsuo Takanishi ◽  
Kayoko Ohtsuki ◽  
...  

This paper discusses a jaw movement training robot implementing a 6-DOF (degrees of freedom) parallel mechanism, and its application to mouth opening and closing and lateral movement training. Temporomandibular joints (TMJ) syndrome prevents patients from opening their mouths or moving their jaws easily due to problems with mandibular joints, mastication muscles, and other organs involved in food chewing. Conventional therapy involves simple mouth opening apparatuses, although individual techniques vary with the physician. We developed and improved a jaw movement training robot that aids jaw opening and closing and lateral jaw movement training. This system consists of a 6-DOF slave manipulator representing a patient manipulator and a 2-DOF or 3-DOF master manipulator representing the doctor command manipulator.


CoDAS ◽  
2015 ◽  
Vol 27 (4) ◽  
pp. 359-364 ◽  
Author(s):  
Sandro Júnior Henrique Lima ◽  
Leandro de Araújo Pernambuco ◽  
Aline de Lima Lins ◽  
Lucas Carvalho Aragão Albuquerque ◽  
Hilton Justino da Silva

INTRODUCTION: Allergic rhinitis can cause changes in stomatognathic functions, which may alter the mandibular dynamics. Electrognathography is used in the recording of jaw movements, making it valid for analysis of movements in speech.PURPOSE: To characterize the amplitude and velocity of jaw movements during speech in children with and without allergic rhinitis.METHODS: The sample consisted of 32 children aged 7-12 years, treated at a university hospital, divided into two groups: one with rhinitis and the other without rhinitis. To capture the jaw movements during speech, we used an electrognathography with the aid of a list of phonetically balanced figures. For the analysis of data, we used, in addition to descriptive statistics, nonparametric tests, Spearman correlation coefficient and the Mann-Whitney test, with a significant value of p=0.05.RESULTS: No significant difference was observed in jaw movements between groups, with values of p equals to 0.175, 0.650, and 0.462 for amplitude and jaw opening and closing velocity, respectively. However, a strong correlation was observed between the variables velocity and amplitude of mouth opening, being slightly higher in the group of children with allergic rhinitis.CONCLUSION: The amplitude and velocity of jaw movements are found to be similar in children with and without allergic rhinitis, and a correlation exits between these variables. In addition, they were more heterogeneous in the group without allergic rhinitis.


2020 ◽  
Vol 63 (2) ◽  
pp. 499-508 ◽  
Author(s):  
Jimin Lee ◽  
Elizabeth Rodriguez ◽  
Antje Mefferd

Purpose The current study tested jaw movement characteristics and their impact on tongue movement for speech production in individuals with amyotrophic lateral sclerosis (ALS). Specifically, the study examined tongue and jaw movement in multiple directions during jaw opening and closing strokes in individuals with ALS and controls. Method Twenty-two individuals with ALS and 22 controls participated in the current study. Tongue and jaw movements during the production of the words “Iowa” and “Ohio” (produced in a carrier phrase) were recorded using electromagnetic articulography. Tongue and jaw distances were measured for jaw opening and closing strokes. Distance was measured in the anterior–posterior and superior–inferior dimensions (retraction, advancement, lowering, and raising). Results Findings revealed that individuals with ALS exaggerated their jaw opening movements, but not their jaw closing movements, compared to controls. Between the groups, a comparable tongue lowering distance was observed during jaw opening movements. In contrast, reduced tongue raising was observed during the jaw closing movements in individuals with ALS compared to controls. Conclusion The findings suggest that individuals with ALS produce excessive jaw opening movements in the absence of excessive jaw closing movements. The lack of excessive jaw closing movements results in reduced tongue raising in these individuals. Excessive jaw opening movements alone suggest a direction-specific jaw dysfunction. Future studies should examine whether excessive jaw raising can be facilitated and if it enhances tongue raising movement for speech production in individuals with dysarthria secondary to ALS.


1993 ◽  
Vol 69 (2) ◽  
pp. 569-584 ◽  
Author(s):  
Z. J. Liu ◽  
Y. Masuda ◽  
T. Inoue ◽  
H. Fuchihata ◽  
A. Sumida ◽  
...  

1. Rhythmic movements of the jaw, tongue, and hyoid that were induced by stimulation of the cortical masticatory area (CMA) were recorded cineradiographically in the anesthetized rabbit. Jaw movements were also recorded by a laser position detector. 2. The evoked jaw movements were classified into four types: small circular (type A), large circular (type B), large vertical (type C), and crescent-shaped (type D). Among these, types B and D resembled the jaw movements of the food transport cycle and those of the chewing cycle in a masticatory sequence. 3. Each type of jaw movement was associated with a particular pattern of tongue and hyoid movements. In general, the tongue protruded during jaw opening and retracted during jaw closure. The hyoid generally moved upward and forward during jaw opening but downward and backward during jaw closure. 4. Electromyograms (EMGs) were recorded from jaw muscles [masseter (Ma) and digastric (Di) muscles], extrinsic tongue muscles [styloglossus (Sg) and genioglossus (Gg) muscles], and hyoid muscles [sternohyoid (Sh) and geniohyoid (Gh) muscles] during cortically induced rhythmic jaw and tongue movements (CRJTMs). These muscles were classified into two groups: group 1 was activated mainly in the jaw opening phase, and group 2 was activated mainly in the jaw closing and power phases. The Di, Gg, and Gh were included in the former, and the Ma, Sg, and Sh were included in the latter. 5. The timings of EMG activation to a jaw movement cycle were relatively constant for the muscles of group 1, irrespective of the types of CRJTMs, whereas those for the muscles of group 2 altered considerably with the different types of CRJTMs. 6. Relationships of the integrated muscle activity between the Di and Gg and between the Di and Gh were significant, whereas those between the Ma and Sg and between the Ma and Sh were not. 7. When a small strip of polyurethane form of various degrees of hardness was inserted between the opposing molars during CRJTMs, EMG activity of the muscles of group 2 increased with the hardness of the strip. On the other hand, EMG activities of the muscles of group 1 were less affected by the same intraoral stimuli. 8. Two conclusions were reached: first, physiological properties of the CRJTMs and cortically induced rhythmic movements of the hyoid were essentially similar to those observed in natural mastication. This fictive mastication might thus be regarded as a suitable model for simulating natural mastication.(ABSTRACT TRUNCATED AT 400 WORDS)


1994 ◽  
Vol 195 (1) ◽  
pp. 147-167
Author(s):  
H Pfau ◽  
U Koch

We describe the functional morphology of the singing apparatus of the cricket. There are three main functional sections of song mechanics, which partly overlap: (1) preparation for singing (lifting of the wings) and the reverse process (lowering of the wings at the end of the song); (2) singing movements (closing and opening of the wings); and (3) movements that adjust the pressure of the plectrum on the file (engagement force). In the case of song preparation, the mesotergum + first axillaries + second axillaries + wings form a functional unit. This unit is moved around a transverse hinge axis, which runs through both fulcrum joints. The muscles suitable for wing lifting are the prothoracic furca muscle and the mesothoracic tegula muscle. Those suitable for wing lowering are the prothoracic dorsolongitudinal muscles and the mesothoracic axillary 4, subalar and furca muscles. Lifting and lowering of the wings are superimposed by bistable mechanisms, which are adjustable (mesothoracic medial dorsolongitudinal muscles). In the case of closing movements (dorsoventral muscles) and opening movements (basalar and subalar muscles), the mesotergum and the wings are moved relative to each other, as for flight movements, but with the wings remaining folded back. The mesotergum is rotated down (closing) and up (opening) around a transverse hinge axis that runs through the caudal joints between the mesotergum and postnota. The path of movement of the wing and its sound-generating structure (i.e. plectrum or file respectively) is determined by an obliquely oriented hinge axis between the mesotergum and first axillary. During opening and closing, the lifted singing position of the wings is stabilized by the medial dorsolongitudinal muscles. We also discuss the role of other muscles that affect singing movements. The third axillary (and its muscle) and the postnotum [and its muscles, the furca muscle and the lateral (short) dorsolongitudinal muscle] are the main elements in the system that adjusts the engagement force of the wings. When left axillary 3 muscle contracts, the medial part of the left third axillary is rotated caudally (in its vertical hinge joint with the first median plate) against the anal part of the wing. The anal part is bent and rotated upwards, increasing the pressure of the left plectrum against the right file. Conversely, the right axillary 3 muscle, which moves the file away from the plectrum, is able to reduce the pressure. The left furca muscle (the antagonist of left axillary 3 muscle) and the left lateral (short) dorsolongitudinal muscle (the 'synergist' of left axillary 3 muscle), and the corresponding muscles on the right side (which have opposite functions), allow a large range of different engagement forces. The results are compared with the work of other authors on the functional morphology of this system and with the results of electrophysiological investigations. New aspects of the evolution of the singing mechanisms are discussed.


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