Lip Compression Research Articles

Design and Experiment Verification to Combined Dynamic Seal of Wide-Speed Hydraulic Motor Pump

To reduce the wear of lip seal of wide-speed hydraulic motor pump and prolong the service life, the lip compression is reduced and the non-contacting labyrinth seal is used as the front stage, forming a series combined dynamic seal (CDS). The reliability of CDS in the wide-speed range is verified by model experiment. Initially, the structure form and dimension of labyrinth seal with relatively small leakage and heat production were determined by model experiment. Then, by establishing the model of lip seal and simulating the static structure, the relationship between the compression and maximum contact pressure of the lip was obtained. Finally, using the CDS which is formed by combining the different lip seals with the selected labyrinth seal to carry out experiments, the leakage, temperature distribution and lip wear were obtained. The results show that trapezoidal tooth labyrinth seal (TTLS) has better sealing effect and less heat production. When the sealing clearance is 0.1 mm and 0.3 mm, it accounts for 0.11% and 0.32% of the rotor diameter, respectively. Under the same conditions, the smaller the proportion, the better the sealing effect, but the higher the heat production. With the increase of compression, the maximum sealing pressure first increases and then decreases. When the compression of the lip exceeds 0.1 mm, the CDS will not leak significantly in a wide-speed range, but the greater is the compression, the faster is the temperature rise in the closed cavity. Lip wear is positively correlated with pv and the wear decreases with the decrease of compression.

Effect of upper lip compression on pain reduction during local anesthesia. A split-mouth randomized clinical trial.

Effect of upper lip compression on pain reduction during local anesthesia. A split-mouth randomized clinical trial.

Orofacial Muscle Strength across the Dysarthrias.

This study compared orofacial muscle strength between normal and dysarthric speakers and across types of dysarthria, and examined correlations between strength and dysarthria severity. Participants included 79 speakers with flaccid, spastic, mixed spastic–flaccid, ataxic, or hypokinetic dysarthria and 33 healthy controls. Maximum pressure generation (Pmax) by the tongue, lips, and cheeks represented strength. Pmax was lower for speakers with mixed spastic–flaccid dysarthria for all tongue and lip measures, as well as for speakers with flaccid or spastic dysarthria for anterior tongue elevation and lip compression. Anterior tongue elevation and cheek compression tended to be lower than normal for the hypokinetic group. Pmax did not differ significantly between controls and speakers with ataxic dysarthria on any measure. Correlations were generally weak between dysarthria severity and orofacial weakness but were stronger in the dysarthria groups with more prominent orofacial weakness. The results generally support predictions that orofacial weakness accompanies flaccid and/or spastic dysarthria but not ataxic dysarthria. The findings support including type of dysarthria as a variable of interest when examining orofacial weakness in motor speech disorders.

The Electrical Activity of the Orbicularis Oris Muscle in Children with Down Syndrome-A Preliminary Study.

The aim of this study was to assess the electrical activity of the superior (SOO) and inferior (IOO) orbicularis oris muscles in children with Down syndrome (DS) and in children without DS. After applying the inclusion and exclusion criteria, 30 subjects were eligible to participate in the later stages of the research—15 subjects with DS (mean age 10.1 ± 1.1) and 15 healthy controls (mean age 9.8 ± 1.0). The electrical potentials of the SOO and IOO muscles were recorded using a DAB-Bluetooth electromyography machine (Zebris Medical GmbH, Germany) during the following tasks: At clinical rest, saliva swallowing, lip protrusion, lip compression, and production of the syllable/pa/. The Mann–Whitney U test was conducted to compare the study results between the groups. An analysis of the electromyographical (EMG) recordings showed that the electrical activity of the orbicularis oris muscle in children with DS and lip incompetence was significantly higher compared to healthy children during saliva swallowing, lip compression, and when producing the syllable/pa/, and this may suggest greater muscular effort due to the need to seal the lips during these functional conditions.

Auditory startle disrupts speech coordination

Abstract Speech production requires temporal coordination between the actions of different functional groupings of muscles in the human body. Crucially, such functionally organized units, or “modules”, may be susceptible to disruption by an external stimulus such as a startling auditory stimulus (SAS; >120dB), enabling a possible window into the internal structure of learned speech movements. Following on the observation that SAS is known to accelerate the release of pre-planned actions, the current study examines lip kinematics in SAS-induced responses during speech movements to test whether this accelerated release applies on the scale of entire syllables or on the scale of smaller functional units. Production measures show that SAS-elicited bilabial movements in [ba] syllables are prone to disruption as measured by discontinuity in velocity profiles. We use a 3D finite element method (FEM) biomechanical model to simulate the temporal interaction between muscle groupings in speech. Simulation results indicate that this discontinuity can be accounted for as an instance of temporally decoupled coordination across neuromuscular modules. In such instances, the muscle groupings controlling lip compression and jaw opening, which normally fire sequentially, appear more likely to be activated synchronously.

Superior Orbicularis Oris Muscle Activity in Children Surgically Treated for Bilateral Complete Cleft Lip and Palate.

The aim of this cross-sectional study was to evaluate the electromyographic activity of the superior orbicularis oris muscle both in children surgically treated for bilateral complete cleft lip and palate (BCCLP) as well as in subjects without BCCLP. The study comprised 77 children aged 6.6 to 12.5 years. All the patients with clefts had previously undergone lip and palate surgery. The upper lip electromyographic (EMG) assessments were made with a DAB-Bluetooth device (Zebris Medical GmbH, Germany) at rest, while swallowing saliva, protruding lips and compressing lips. EMG measurements were also made when the subjects produced phonemes /p/, /b/, and /m/ with the vowel /a/. The Mann-Whitney U test was applied to statistically analyze the EMG values. Significantly higher median upper lip EMG activity under working conditions such as swallowing saliva, lip compression, and production of the phoneme /p/ with the vowel /a/ was observed in patients with BCCLP compared to those without a cleft. The results of the study showed that the upper lip muscle activity increases in children with BCCLP when swallowing saliva, compressing lips and during some speech movement tasks. This may be important in the aspect of the effect of surgical lip repair on the craniofacial growth.

Labiodentalization of Korean bilabials

The present study examines the interaction of Korean bilabials in natural speech during neutral and smiling conditions to determine whether labiodentalization occurs and, if it does, how the body resolves the conflict between lip spreading and lip compression in smiled speech. Results from various Korean YouTube videos indicate that despite the absence of labiodental tokens in the Korean language inventory, bilabial stops are compromised in smiled speech in being realized as labiodental tokens.

Wireless Sensing of Lower Lip and Thumb-Index Finger 'Ramp-and-Hold' Isometric Force Dynamics in a Small Cohort of Unilateral MCA Stroke: Discussion of Preliminary Findings.

Automated wireless sensing of force dynamics during a visuomotor control task was used to rapidly assess residual motor function during finger pinch (right and left hand) and lower lip compression in a cohort of seven adult males with chronic, unilateral middle cerebral artery (MCA) stroke with infarct confirmed by anatomic magnetic resonance imaging (MRI). A matched cohort of 25 neurotypical adult males served as controls. Dependent variables were extracted from digitized records of ‘ramp-and-hold’ isometric contractions to target levels (0.25, 0.5, 1, and 2 Newtons) presented in a randomized block design; and included force reaction time, peak force, and dF/dtmax associated with force recruitment, and end-point accuracy and variability metrics during the contraction hold-phase (mean, SD, criterion percentage ‘on-target’). Maximum voluntary contraction force (MVCF) was also assessed to establish the force operating range. Results based on linear mixed modeling (LMM, adjusted for age and handedness) revealed significant patterns of dissolution in fine force regulation among MCA stroke participants, especially for the contralesional thumb-index finger followed by the ipsilesional digits, and the lower lip. For example, the contralesional thumb-index finger manifest increased reaction time, and greater overshoot in peak force during recruitment compared to controls. Impaired force regulation among MCA stroke participants during the contraction hold-phase was associated with significant increases in force SD, and dramatic reduction in the ability to regulate force output within prescribed target force window (±5% of target). Impaired force regulation during contraction hold-phase was greatest in the contralesional hand muscle group, followed by significant dissolution in ipsilateral digits, with smaller effects found for lower lip. These changes in fine force dynamics were accompanied by large reductions in the MVCF with the LMM marginal means for contralesional and ipsilesional pinch forces at just 34.77% (15.93 N vs. 45.82 N) and 66.45% (27.23 N vs. 40.98 N) of control performance, respectively. Biomechanical measures of fine force and MVCF performance in adult stroke survivors provide valuable information on the profile of residual motor function which can help inform clinical treatment strategies and quantitatively monitor the efficacy of rehabilitation or neuroprotection strategies.

Influence of sex and resistance training status on orofacial muscle strength and morphology in healthy adults between the ages of 18 and 40: A cross-sectional study.

To compare the orofacial muscle strength and facial muscle thickness between resistance-trained and non-resistance trained men and women. Resistance-trained (25 men and 22 women) and non-resistance trained (21 men and 30 women) adults (18-40 years) had standard measurements of orofacial muscle strength (ie, anterior tongue elevation, cheek compression, and lip compression) and ultrasound measurements of facial muscle thickness. Body composition (percent fat, etc.) was estimated using ultrasound prediction Equations. A Bayesian analysis of variance (ANOVA) with between subject factors of training status (yes/no) and sex (man/woman) were used to determine differences in muscle size and strength. Body mass, height, and percent fat were similar between resistance-trained and non-resistance trained individuals, while appendicular lean mass was higher in resistance-trained. There were no differences in orofacial muscle strength between resistance-trained and non-resistance trained. However, men had greater strength in every task except for anterior tongue strength which was similar between sexes (men: 66 vs women: 64 kPa). Handgrip strength was greater in men and in those who were resistance-trained. The frontalis muscle was greater in women than in men and in those who were non-resistance-trained than those resistance-trained. None of the other muscles differed by training status, however, all were greater in men. Results from our cross-sectional study would suggest that exercise-stimulation to the facial muscles during resistance training of the limbs and trunk did not reach a level where orofacial muscle strength could be changed. Sex differences in facial muscle thickness are very unique, although the reasons are unclear.

A Practical Method for Assessing Lip Compression Strengthening in Healthy Adults

There is no practical and accessible assessment method to evaluate lip muscle compression strength. The purpose of this study was to examine the relationship between the standard method (i.e., Iowa Oral Performance Instrument) and a practical method in healthy adults. In order to achieve our research purpose, ninety-eight healthy adults (18–40 years) completed lip compression strength measurements (standard method) and lip grasping performance tests using a standard recyclable plastic water bottle (practical method). In the overall sample, the mean and standard deviation for standard method and practical method was 26.7 (7.0) kPa and 255 (119) g, respectively. For the overall sample (n = 98), there was a positive relationship between the two strength tasks [r = 0.56 (0.41, 0.68)]. When separated by sex, positive correlations were observed for men and women with no differences between the observed correlations [difference of 0.06 (−0.2646, 0.3917)]. This result indicates that those individuals who are strong in the standard task will often be strong in the practical task. Future research is needed to determine how well changes in each test track with each other in response to a lip strength training program.

Engaging the Articulators Enhances Perception of Concordant Visible Speech Movements.

Purpose This study aimed to test whether (and how) somatosensory feedback signals from the vocal tract affect concurrent unimodal visual speech perception. Method Participants discriminated pairs of silent visual utterances of vowels under 3 experimental conditions: (a) normal (baseline) and while holding either (b) a bite block or (c) a lip tube in their mouths. To test the specificity of somatosensory-visual interactions during perception, we assessed discrimination of vowel contrasts optically distinguished based on their mandibular (English /ɛ/-/æ/) or labial (English /u/-French /u/) postures. In addition, we assessed perception of each contrast using dynamically articulating videos and static (single-frame) images of each gesture (at vowel midpoint). Results Engaging the jaw selectively facilitated perception of the dynamic gestures optically distinct in terms of jaw height, whereas engaging the lips selectively facilitated perception of the dynamic gestures optically distinct in terms of their degree of lip compression and protrusion. Thus, participants perceived visible speech movements in relation to the configuration and shape of their own vocal tract (and possibly their ability to produce covert vowel production-like movements). In contrast, engaging the articulators had no effect when the speaking faces did not move, suggesting that the somatosensory inputs affected perception of time-varying kinematic information rather than changes in target (movement end point) mouth shapes. Conclusions These findings suggest that orofacial somatosensory inputs associated with speech production prime premotor and somatosensory brain regions involved in the sensorimotor control of speech, thereby facilitating perception of concordant visible speech movements. Supplemental Material https://doi.org/10.23641/asha.9911846.

Effects of weakness of orofacial muscles on swallowing and communication in FSHD.

This study explores the use of quantitative data on strength and fatigability of orofacial muscles in patients with facioscapulohumeral muscular dystrophy (FSHD) and assesses the frequency of swallowing and communication difficulties and their relationship to orofacial muscle involvement. We included 43 patients with FSHD and 35 healthy controls and used the Iowa Oral Performance Instrument (IOPI) to obtain quantitative measurements of strength and endurance of lip compression, cheek (buccodental) compression, and tongue elevation. For the assessment of swallowing and communication difficulties, we used the dysphagia-specific quality of life (SWAL-QOL) and Communicative Participation Item Bank questionnaires. Cheek compression strength was reduced in patients with FSHD compared to healthy controls. Dysphagia and difficulty with verbal communication were reported by 25% and 35% of patients, respectively, and correlated to cheek compression strength and endurance and to anterior tongue elevation endurance. Prolonged cheek compression or anterior tongue elevation endurance (decreased fatigability) made swallowing or speech problems less likely to occur. Cheek compression strength is the most sensitive IOPI measure for orofacial weakness in FSHD. Orofacial weakness contributes to dysphagia and speech difficulties in FSHD, which are both common, though generally mild. Higher endurance of orofacial muscles was associated with a lower chance of dysphagia or speech problems. More research is required for further refinement of the pattern of facial muscle involvement in FSHD and to provide new insights for improvement of speech and language therapy.

Electromyographic analysis of superior orbicularis oris muscle function in children surgically treated for unilateral complete cleft lip and palate

PurposeThe aim of this study was to assess the electrical activity of the superior orbicularis oris muscle in children surgically treated for unilateral complete cleft lip and palate (UCCLP). Material and methodsThe sample comprised 45 patients 6.38–12.68 years of age with UCCLP and 40 subjects 6.61–11.71 years of age with no clefts. Electromyographical (EMG) recordings were taken with a DAB-Bluetooth Instrument (Zebris Medical GmbH, Germany) in the rest position and during saliva swallowing, lip protrusion and reciprocal compression of the lips, as well as while producing the phonemes /p/, /b/, and /m/ combined with the vowel /a/. ResultsThe electrical activity of the upper lip during saliva swallowing and lip compression was significantly greater in the cleft group. Similar resting level activity was observed in both groups. During the production of the /p/, /b/, and /m/ phonemes combined with the vowel /a/ the results showed no significant differences in the EMG activity between children with UCCLP and noncleft subjects. ConclusionPatients with UCCLP have abnormal upper lip function characterized by increased activity of the superior orbicularis oris muscle during saliva swallowing and lip compression, and this may affect facial morphology.

A universal bias in adult vowel perception – By ear or by eye

Speech perceivers are universally biased toward “focal” vowels (i.e., vowels whose adjacent formants are close in frequency, which concentrates acoustic energy into a narrower spectral region). This bias is demonstrated in phonetic discrimination tasks as a directional asymmetry: a change from a relatively less to a relatively more focal vowel results in significantly better performance than a change in the reverse direction. We investigated whether the critical information for this directional effect is limited to the auditory modality, or whether visible articulatory information provided by the speaker’s face also plays a role. Unimodal auditory and visual as well as bimodal (auditory-visual) vowel stimuli were created from video recordings of a speaker producing variants of /u/, differing in both their degree of focalization and visible lip rounding (i.e., lip compression and protrusion). In Experiment 1, we confirmed that subjects showed an asymmetry while discriminating the auditory vowel stimuli. We then found, in Experiment 2, a similar asymmetry when subjects lip-read those same vowels. In Experiment 3, we found asymmetries, comparable to those found for unimodal vowels, for bimodal vowels when the audio and visual channels were phonetically-congruent. In contrast, when the audio and visual channels were phonetically-incongruent (as in the “McGurk effect”), this asymmetry was disrupted. These findings collectively suggest that the perceptual processes underlying the “focal” vowel bias are sensitive to articulatory information available across sensory modalities, and raise foundational issues concerning the extent to which vowel perception derives from general-auditory or speech-gesture-specific processes.

A comparison of lip positions for /ɨ/ and /Ɯ/ in Bora

Bora is a Witotoan language spoken by about 750 persons in the Amazon jungle of Peru and 100 in Colombia. Its phonemic vowels are /i e a o ɨ Ɯ/ (Thiesen and Weber 2012). A contrast between a central and a back vowel which are otherwise identical is theoretically significant since it shows that a binary feature [ + /-back] is too weak to encode all phonological contrasts along the front/back dimension. The three high vowels of Bora have been acoustically confirmed with measurements of F1-F3 (Parker 2001), but there has been no articulatory investigation of these vowels. Impressionistically all of the Bora vowels except /o/ are articulated with unrounded lips. However, Ladefoged and Maddieson (1996) note that high back unrounded vowels in languages such as Japanese involve a gesture of lip compression or inrounding. Consequently, an important research question is whether the distinction between /ɨ/ and /Ɯ/ in Bora can be relegated to a difference in lip positions rather than to a primary contrast in tongue backness? To test this hypothesis, we obtained video recordings of native speakers on location in a Bora village (6 males and 7 females), and we report lip position data from these recordings.

Prevalence of the Short Face Pattern in Individuals of Bauru-Brazil.

Aim:This study aimed at assessing the prevalence and severity of short face pattern in ethnically different individuals.Material and Methods:The sample comprised 4,409 Brazilians (2,192 females and 2,217 males), with a mean age of 13 years, enrolled in secondary schools in the municipality of Bauru. The sample inclusion criteria involved subjects with vertically impaired facial relationship based on excessive lip compression, when standing at natural head position, with the lips at rest. Once short face syndrome had been identified, the individuals were classified into three severity subtypes: mild, moderate, and severe. The sample was then stratified by ethnic background as White (Caucasoid), Black (African descent), Brown (mixed Caucasian–African descent), Yellow (Asian descent), and Brazilian Indian (Native Brazilian descent), using the Brazilian Institute of Geography and Statistics classification. The chi-square test at the 5% significance level was used to compare frequency ratios of individuals with vertically impaired facial relationships and across different ethnicities, according to severity.Results:The prevalence of short face pattern was 3.15%, as 1.11%, 1.99%, and 0.02% considered mild, moderate and severe subtypes, respectively. The severe subtype was rare (0.02%) and found only in one White individual. The White group had the highest relative frequency (45.53%) of the moderate subtype, followed by Brown individuals (43.40%). In the mild subtype, Yellow (68.08%) and White (62.21%) individuals showed similar and higher relative frequency values. Conclusion:The prevalence of short face pattern was 3.15%, and White individuals had the highest prevalence.

Effect of orofacial myofunctional exercise on the improvement of dysphagia patients' orofacial muscle strength and diadochokinetic rate.

[Purpose] Measurement of the diadochokinetic rate can provide useful information on swallowing rehabilitation in the oral phase by elucidating the speed and regularity of movement of muscles related to the lips, tongue, and chin. This study investigated the effect of a three-week period of orofacial myofunctional exercise on the improvement of cheek, tongue, and lip muscle strength and diadochokinetic rate in dysphagia patients. [Subjects and Methods] This study employed a pretest-posttest control group design. Both orofacial myofunctional exercise and the temperature-tactile stimulation technique were applied to the experimental group (n=23), while only the temperature-tactile stimulation technique was applied to the control group (n=25). [Results] Tongue elevation, tongue protrusion, cheek compression, lip compression, and alternating motion rate were more significantly improved in the experimental group than in the control group. [Conclusion] Orofacial myofunctional exercise is effective in the rehabilitation of swallowing function in the oral phase in dysphagia patients by improving orofacial muscle strength and response rate.

Producing whole speech events: Anticipatory lip compression in bilabial stops

Bilabial stops /b/, /p/, and /m/ ostensibly share a common lip constriction. Recent evidence shows that different bilabial stops involve distinct facial muscle activations, suggesting that oral speech movements anticipate aerodynamic conditions [Gick et al. Proc. Acoust. (2012) 2pSC1]. The present study investigates how the lips themselves behave in whole speech events. Existing models of speech production governing only articulatory motions predict that lip compression would respond to changes in aerodynamic conditions rather than anticipating such changes; a model that includes whole events predicts anticipatory activation of lip muscles with concomitant kinematic lip compression, but only in cases where a real increase in air pressure is expected. Lip kinematics were recorded using OptoTrak to trace lip movements of bilabial stops in response to imperative acoustic stimuli. Results show consistent anticipatory lip compression in spoken /b/ and /p/, but not in non-speech jaw opening movements and only sporadic compression in mouthed /b/ and /p/, where air pressure is not expected to increase. Biomechanical simulation using an orofacial model developed within the Artisynth simulation toolkit (www.artisynth.org) confirms anticipatory muscle activations. These findings support a model of speech tasks wherein coordinated body-level muscular systems govern whole speech events.

Interpreting arterial blood gases

Objective This study explores the use of quantitative data on strength and fatigability of orofacial muscles in patients with facioscapulohumeral muscular dystrophy (FSHD) and assesses the frequency of swallowing and communication difficulties and their relationship to orofacial muscle involvement. Methods We included 43 patients with FSHD and 35 healthy controls and used the Iowa Oral Performance Instrument (IOPI) to obtain quantitative measurements of strength and endurance of lip compression, cheek (buccodental) compression, and tongue elevation. For the assessment of swallowing and communication difficulties, we used the dysphagia-specific quality of life (SWAL-QOL) and Communicative Participation Item Bank questionnaires. Results Cheek compression strength was reduced in patients with FSHD compared to healthy controls. Dysphagia and difficulty with verbal communication were reported by 25% and 35% of patients, respectively, and correlated to cheek compression strength and endurance and to anterior tongue elevation endurance. Prolonged cheek compression or anterior tongue elevation endurance (decreased fatigability) made swallowing or speech problems less likely to occur. Conclusion Cheek compression strength is the most sensitive IOPI measure for orofacial weakness in FSHD. Orofacial weakness contributes to dysphagia and speech difficulties in FSHD, which are both common, though generally mild. Higher endurance of orofacial muscles was associated with a lower chance of dysphagia or speech problems. More research is required for further refinement of the pattern of facial muscle involvement in FSHD and to provide new insights for improvement of speech and language therapy.

Feed-forward control of phonetic gestures in consonant–vowel syllables: Evidence from responses to auditory startle.

Speech production like other limb movements relies on both feed-forward and feedback mechanisms. Use of a startling auditory stimulus (>90 dB) has been shown to trigger fast, accurate feed-forward performances in upper limb movements prior to access to feedback information [Valls-Solé et al. (1999), J. Physiol. 516: 931–938; Carlsen et al. (2004), J. Mot. Behav. 36: 253–264]. This startle paradigm is applied to test whether pre-programed, feed-forward speech production differs in phonetic detail from production with access to feedback. The experiment examined the production of the CV syllable [ba], starting with the mouth either open or closed. This speech production was triggered either by a control stimulus (82 dB) or by a startling stimulus (124 dB). Results from ten participants showed that lip compression occurred for both starting conditions (mouth open and mouth closed), and also indicated that the timing relationships of the articulators were stable across control trials and startle trials. The acoustics of syllables, formant values, and maximum amplitudes, were consistent across control trials and startle trials, suggesting that the production of pre-programmed gestural configurations in CV syllables may be executed under exclusively feed-forward control.