Coordination of Velopharyngeal Muscle Activity during Positioning of the Soft Palate

1994 ◽  
Vol 31 (1) ◽  
pp. 45-55 ◽  
Author(s):  
Jerald B. Moon ◽  
Alice E. Smith ◽  
John W. Folkins ◽  
Jon H. Lemke ◽  
Michael Gartlan
Keyword(s):  
Statistical Model ◽  
Soft Palate ◽  
Muscle Activity ◽  
Normal Adult ◽  
Activity Levels ◽  
Levator Veli Palatini ◽  
Closure Level

The relative contributions of the levator veli palatini, palatoglossus, and palatopharyngeus muscles were assessed relative to a range of positions of the velopharynx during production of the vowels [a] and [I] by four normal adult speakers. The results indicate that velopharyngeal positioning is determined by the relative contributions of the levator veli palatini, palatoglossus, and palatopharyngeus muscles. There was an increase In coefficients of determination (i.e., amount of closure level variability explained) when activity levels of all three muscles are included in the statistical model compared to activity in any one muscle analyzed independently. Both consistent and inconsistent relations among activity levels in the three velopharyngeal muscles studied were observed across speaker and vowel produced.

Morphological Characterization of the Levator Veli Palatini Muscle in Children Born with Cleft Palates

2001 ◽  
Vol 38 (5) ◽  
pp. 438-448 ◽  
Author(s):  
Rolf Lindman ◽  
Gunnar Paulin ◽  
Per S. Stål
Keyword(s):  
Cleft Palate ◽  
Soft Palate ◽  
Surgical Repair ◽  
Fiber Type ◽  
Muscle Spindles ◽  
Morphological Characterization ◽  
Velopharyngeal Insufficiency ◽  
Normal Adult ◽  
Levator Veli Palatini

Objective: The aim of this study was to analyze, morphologically and biochemically, one of the soft palate muscles, the levator veli palatini (LVP), in children born with cleft palate. Subjects and Methods: Biopsies were obtained from nine male and three female infants in connection with the early surgical repair of the hard and soft palate. Samples from five adult normal LVP muscles were used for comparison. The muscle morphology, fiber type and myosin heavy chain (MyHC) compositions, capillary supply, and content of muscle spindles were analyzed with different enzyme-histochemical, immunohistochemical, and biochemical techniques. Results: Compared with the normal adult subjects, the LVP muscle from the infantile subjects with cleft had a smaller mean fiber diameter, a larger variability in fiber size and form, a higher proportion of type II fibers, a higher amount of fast MyHCs, and a lower density of capillaries. No muscle spindles were observed. Moreover, one-third of the biopsies from the infantile subjects with cleft LVP either lacked muscle tissue or contained only a small amount. Conclusions: The LVP muscle from children with cleft palate has a different morphology, compared with the normal adult muscle. The differences might be related to different stages in maturation of the muscles, changes in functional demands with growth and age, or a consequence of the cleft. The lack of contractile tissue in some of the cleft biopsies offers one possible explanation to a persistent postsurgical velopharyngeal insufficiency in some patients, despite a successful surgical repair.

Soft palate muscle responses to negative upper airway pressure

1999 ◽  
Vol 86 (2) ◽  
pp. 523-530 ◽  
Author(s):  
T. C. Amis ◽  
N. O’Neill ◽  
J. R. Wheatley ◽  
T. van der Touw ◽  
E. di Somma ◽  
...  
Keyword(s):  
Soft Palate ◽  
Muscle Activity ◽  
Airway Pressure ◽  
Upper Airway ◽  
Emg Activity ◽  
Afferent Activity ◽  
Afferent Pathways ◽  
Levator Veli Palatini ◽  
Anesthetized Dogs ◽  
Muscle Responses

The afferent pathways and upper airway receptor locations involved in negative upper airway pressure (NUAP) augmentation of soft palate muscle activity have not been defined. We studied the electromyographic (EMG) response to NUAP for the palatinus, tensor veli palatini, and levator veli palatini muscles in 11 adult, supine, tracheostomized, anesthetized dogs. NUAP was applied to the nasal or laryngeal end of the isolated upper airway in six dogs and to four to six serial upper airway sites from the nasal cavity to the subglottis in five dogs. When NUAP was applied at the larynx, peak inspiratory EMG activity for the palatinus and tensor increased significantly ( P< 0.05) and plateaued at a NUAP of −10 cmH2O. Laryngeal NUAP failed to increase levator activity consistently. Nasal NUAP did not increase EMG activity for any muscle. Consistent NUAP reflex recruitment of soft palate muscle activity only occurred when the larynx was exposed to the stimulus and, furthermore, was abolished by bilateral section of the internal branches of the superior laryngeal nerves. We conclude that soft palate muscle activity may be selectively modulated by afferent activity originating in the laryngeal and hypopharyngeal airway.

Simulate and sense force exertions during virtual patient transfer tasks

2020 ◽  
Vol 64 (1) ◽  
pp. 2092-2096
Author(s):  
Ken Chen ◽  
Rebecca Widmayer ◽  
Karen B. Chen
Keyword(s):  
Muscle Activity ◽  
Fine Tuning ◽  
Activity Levels ◽  
Patient Lifting ◽  
Perceived Workload ◽  
Specific Muscle ◽  
Muscle Groups ◽  
Forceful Exertion ◽  
Lifting Task ◽  
Transfer Tasks

Virtual reality (VR) is commonplace for training, yet simulated physical activities in VR do not require trainees to engage and contract the muscle groups normally engaged in physical lifting. This paper presents a muscle activity-driven interface to elicit the sensation of forceful, physical exertions when lifting virtual objects. Users contracted and attained predefined muscle activity levels that were calibrated to user-specific muscle activity when lifting the physical counterpart. The overarching goal is to engage the appropriate muscles, and thereby encourage and elicit behaviors normally seen in the physical environment. Activities of 12 key muscles were monitored using electromyography (EMG) sensors while they performed a three-part patient lifting task in a Cave Automatic Virtual Environment. Participants reported higher task mental loads and less physical loads for the virtual lift than the physical lift. Findings suggest the potential to elicit sensation of forceful exertion via EMG feedback but needed fine-tuning to offset perceived workload.

Oral Air Pressure and Nasal Air Flow Rate on Levator Veli Palatini Muscle Activity in Patients Wearing a Speech Appliance

1995 ◽  
Vol 32 (5) ◽  
pp. 382-389 ◽  
Author(s):  
Takashi Tachimura ◽  
Hisanaga Hara ◽  
Takeshi Wada
Keyword(s):  
Flow Rate ◽  
Muscle Activity ◽  
Neural Control ◽  
Air Flow ◽  
Air Pressure ◽  
Electromyographic Activity ◽  
Air Flow Rate ◽  
Circular Area ◽  
Pharyngeal Bulb ◽  
Levator Veli Palatini

This study was designed to determine if levator veli palatini muscle activity can be elicited by simultaneous changes in oral air pressure and nasal air flow when a speech appliance is in place. The speech appliances routinely worn by 15 subjects were each modified experimentally by drilling a hole in the vertical center of the pharyngeal bulb. The air flow rate into the nasal cavity through the opening in the bulb was altered by changing the circular area of the opening in the bulb from the occluded condition (Condition I), to circular area of 12.6 mm2 (4 mm in diameter; Condition II), and then to 38.5 mm2 (7 mm in diameter; Condition III). Electromyographic activity was measured from the levator veli palatini muscle with changes in nasal air flow rate and oral air pressure. Levator veli palatini muscle activity was correlated with changes in nasal air flow and oral air pressure. Increases in levator veli palatini muscle activity were associated with increases in nasal air flow rate compared to oral air pressure changes. The results indicated that aerodynamic variables of nasal air flow and oral air pressure might be involved in the neural control of speech production in individuals wearing a speech appliance, even if the subjects exhibit velopharyngeal incompetence without using a speech appliance. Also, the stimulating effect of bulb reduction therapy on velopharyngeal function might be achieved through the change in aerodynamic variables in association with the bulb reduction.

Upper extremity muscle activity during household floor vacuuming with upright cleaners

2018 ◽  
Vol 62 (1) ◽  
pp. 1018-1021
Author(s):  
Haerim Bak ◽  
Clive D’Souza ◽  
Gwanseob Shin
Keyword(s):  
Upper Extremity ◽  
Muscle Activity ◽  
Maximum Voluntary Contraction ◽  
Voluntary Contraction ◽  
Activity Levels ◽  
Physical Demands ◽  
Study Results ◽  
Musculoskeletal Problems ◽  
Muscle Groups ◽  
Intensive Work

Physical demands of household carpet vacuuming and associated risks for musculoskeletal problems have received little attention although the level of muscle exertions is often assumed to be similar to that of occupational vacuuming. The aim of this study was to quantitatively assess the level of muscle activities of the upper extremity during carpeted floor vacuuming with household upright vacuum cleaners. Eighteen participants conducted four different carpet vacuuming tasks with two different cleaner models. Electromyography data from seven upper extremity muscles were collected. Median muscle activity ranged from 4.5% to 47.5% of the maximum voluntary contraction capacity for female participants and from 2.7% to 23.6% for male participants. Normalized muscle activity levels were significantly higher in women compared to men across tasks and muscle groups. Study results suggest that home vacuuming with upright vacuum cleaners is physically intensive work, especially for female users who are less physically capable.

Patterns of Abnormal Myogenesis in Human Cleft Palates

1994 ◽  
Vol 31 (5) ◽  
pp. 345-350 ◽  
Author(s):  
Steven R. Cohen ◽  
Lynn L. Chen ◽  
Alphonse R. Burdi ◽  
Carroll-Ann Trotman
Keyword(s):  
Light Microscopy ◽  
Cleft Palate ◽  
Muscle Fiber ◽  
Soft Palate ◽  
Crown Rump Length ◽  
Levator Veli Palatini ◽  
Myotube Formation ◽  
Preliminary Study ◽  
Mesenchymal Condensation ◽  
First Time

To test the hypothesis that soft palate muscles are abnormal in cleft palate, we compared soft palate morphogenesis in fetuses with cleft palate (n=4) to age-matched (n=3) and nonmatched (n=1) control specimens. The morphologic status of all soft palate and masticatory structures were classified into one of six stages based on the level of histogenesis. At 54 mm crown-rump length (CRL), the levator veli palatini (L), palatopharyngeus (PP), and palatoglossus (PG) in cleft subjects demonstrated mesenchymal condensation into myoblastic fields, lagging behind the control specimens (97 mm CRL), which displayed definitive fields of myoblasts and myotube formation. In the 175 mm and 225 mm cleft and the 170 mm and 192 mm control specimens, muscular morphology was similar and had reached its postnatal appearance for the tensor veli palatini (175 m only) and L, PP, PG (225 mm only). Muscle fiber directions were, however, disoriented and disorganized, especially close to the medial epithelial edge of the cleft. The levator veli palatini, could not be distinguished as a discrete muscle in the cleft specimens, and what we believed to be the PP and PG seemed “normal” at the level of light microscopy, but malpositioned in a superior direction. This preliminary study demonstrates for the first time that early myogenesis in cleft palates differs from normal.

Validation and comparison of trunk muscle activities in male participants during exercise using an innovative device and abdominal bracing maneuvers

2021 ◽  
pp. 1-8
Author(s):  
Yuki Kurokawa ◽  
Satoshi Kato ◽  
Satoru Demura ◽  
Kazuya Shinmura ◽  
Noriaki Yokogawa ◽  
...  
Keyword(s):  
Muscle Activity ◽  
Muscle Activation ◽  
Voluntary Contraction ◽  
Trunk Muscle ◽  
Erector Spinae ◽  
Trunk Muscles ◽  
Activity Levels ◽  
Significant Difference ◽  
External Oblique ◽  
Internal Oblique

BACKGROUND: Abdominal bracing is effective in strengthening the trunk muscles; however, assessing performance can be challenging. We created a device for performing abdominal trunk muscle exercises. The effectiveness of this device has not yet been evaluated or compared OBJECTIVE: We aimed to quantify muscle activity levels during exercise using our innovative device and to compare them with muscle activation during abdominal bracing maneuvers. METHODS: This study included 10 men who performed abdominal bracing exercises and exercises using our device. We measured surface electromyogram (EMG) activities of the rectus abdominis (RA), external oblique, internal oblique (IO), and erector spinae (ES) muscles in each of the exercises. The EMG data were normalized to those recorded during maximal voluntary contraction (%EMGmax). RESULTS: During the bracing exercise, the %EMGmax of IO was significantly higher than that of RA and ES (p< 0.05), whereas during the exercises using the device, the %EMGmax of IO was significantly higher than that of ES (p< 0.05). No significant difference was observed in the %EMGmax of any muscle between bracing exercises and the exercises using the device (p= 0.13–0.95). CONCLUSIONS: The use of our innovative device results in comparable activation to that observed during abdominal bracing.

Head Movements and Neck Muscle Activity During Air Combat Maneuvering

2020 ◽  
Vol 91 (1) ◽  
pp. 26-31 ◽  
Author(s):  
Roope Sovelius ◽  
Maunu Mäntylä ◽  
Heini Huhtala ◽  
Juha Oksa ◽  
Rasmus Valtonen ◽  
...  
Keyword(s):  
Muscle Activity ◽  
Muscular Activity ◽  
Head Movements ◽  
Neck Muscle ◽  
Activity Levels ◽  
Sitting Posture ◽  
Field Of Vision ◽  
Air Combat ◽  
The Difference ◽  
Neutral Posture

BACKGROUND: The aim of the study was to determine the characteristics of cervical muscle activity in different head movements when using helmet mounted display in air combat maneuvering.METHODS: Cervical EMG was measured with eight F/A-18 pilots using the Joint Helmet Mounted Cueing System (JHMCS) during air combat maneuvering. In-flight Gz acceleration and continuous head position were recorded. Muscular activity was compared between head movements in isolation and combined with torso movement. In addition, the effect of the direction of head movements and the use of head support of the ejection seat on muscle activity was determined.RESULTS: Muscular loading increased in the cervical flexors and extensors when using the torso during targeting beyond the field of vision in the neutral sitting posture; the difference was significant in the flexors, but activity levels were higher in the extensors. Cervical muscles are loaded to a lesser extent if the head is kept in a stable position during Gz loading. Muscular activity in the neck muscles was higher when the pilot was moving the head out of neutral posture rather than toward neutral posture. The use of the headrest as a support decreased muscle activity in the extensors, but resulted in higher activity in the flexor muscles.DISCUSSION: All analyzed conditions were significantly affected by an increase in Gz. An increase of muscle activity with torso movements is considered as a positive factor as it reflects maintained muscular support for the cervical spine. Presented results may be helpful when specific conditioning programs and cockpit ergonomics are developed for fighter pilots.Sovelius R, Mäntylä M, Huhtala H, Oksa J, Valtonen R, Tiitola L, Leino T. Head movements and neck muscle activity during air combat maneuvering. Aerosp Med Hum Perform. 2020; 91(1):26–31.

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