The Effects of Wearing a Medical Mask on the Masticatory and Neck Muscle Activity in Healthy Young Women

The objective of this study was to analyze the influence of wearing a medical mask on masticatory and neck muscle activity in healthy young women. We recruited 66 healthy women aged from 18 to 30 years (mean 23.6 ± 2.3 years). The temporalis anterior (TA), the superficial part of the masseter muscle (MM), the anterior bellies of the digastric muscle (DA), and the middle part of the sternocleidomastoid muscle (SCM) potentials were recorded at rest and during functional activity using an eight-channel device for surface electromyography—BioEMG IIITM. There was a statistically significant decrease in mean TA activity during medical mask measurement compared to no mask examination at rest (2.16 µV vs. 2.58 µV; p = 0.05; ES = 0.2). Significant decreases in resting RMS values were also observed during the medical mask phase in comparison to no mask examination concerning the left MM (1.75 µV vs. 2.17 µV; p = 0.01; ES = 0.3), and mean bioelectrical activity of the MM (1.81 µV vs. 2.15 µV; p = 0.02; ES = 0.2). The differences between the two conditions did not reach the assumed significance level (p > 0.05) in terms of other indices. Wearing a medical mask has a small effect on decreasing the resting potentials of the temporalis anterior and masseter muscles without changing the parameters of activity and asymmetry within the stomatognathic system.

Download Full-text

Brain stem integration of vocalization: role of the midbrain periaqueductal gray

Journal of Neurophysiology ◽

10.1152/jn.1994.72.3.1337 ◽

1994 ◽

Vol 72 (3) ◽

pp. 1337-1356 ◽

Cited By ~ 119

Author(s):

S. P. Zhang ◽

P. J. Davis ◽

R. Bandler ◽

P. Carrive

Keyword(s):

Muscle Activity ◽

Sound Production ◽

Type A ◽

Periaqueductal Gray ◽

Emg Activity ◽

Digastric Muscle ◽

Type B ◽

Motor Patterns ◽

Homocysteic Acid ◽

Lower Amplitude

1. The contribution of the midbrain periaqueductal gray (PAG) to the central regulation of vocalization was investigated by analyzing the electromyographic (EMG) changes in respiratory, laryngeal, and oral muscles evoked by microinjection of D,L-homocysteic acid (DLH) in the PAG of unanesthetized, precollicular decerebrate cats. Moderate to large (6-40 nmol) doses of DLH evoked natural-sounding vocalization as well as increases in inspiratory depth and respiratory rate. 2. Two basic types of vocalization were evoked, each associated with a distinct and characteristic pattern of respiratory, laryngeal and oral EMG changes. Type A vocalization (voiced sounds such as howl/mew/growl) was characterized by excitation of the cricothyroid (CT) and thyro-arytenoid (TA) muscles, and inhibition of the posterior crico-arytenoid (PCA) muscle, whereas type B vocalization (unvoiced hiss sounds) was characterized by excitation of the PCA and TA muscles and no significant activation of the CT muscle. In addition, stronger expiratory (external oblique, internal oblique, internal intercostal) EMG increases were associated with type A responses, and larger increases in genioglossus and digastric muscle activity were associated with type B responses. 3. Microinjections of small doses of DLH (300 pmol-3 nmol), also evoked patterned changes in muscle activity (usually without audible vocalization) that, although of lower amplitude, were identical to those evoked by injections of moderate to large DLH doses. In no such experiments (175 sites) were individual muscles activated by small dose injections of DLH into the PAG. Further, type A vocalization/muscle patterns were evoked from PAG sites caudal to those at which type B vocalization/muscle patterns were evoked. 4. Considered together these results indicate: that the PAG contains topographically separable groups of neurons that coordinate laryngeal, respiratory, and oral muscle patterns characteristic of two fundamental types of vocalization and that the underlying PAG organization takes the form of a representation of muscle patterns, rather than individual muscles. 5. The patterns of EMG activity evoked by excitation of PAG neurons were strikingly similar to previously reported patterns of EMG activity characteristic of major phonatory categories in higher species, including humans (e.g., vowel phonation, voiceless consonant phonation). These findings raise the possibility that the sound production circuitry of the PAG could well be utilized by cortical and subcortical "language structures" to coordinate basic respiratory and laryngeal motor patterns that are necessary for speech.

Download Full-text

On-track Measurements in Motocross: The Correlation of Neck Muscle Activity and Contact Incidents of Helmet and Neck Brace

Procedia Engineering ◽

10.1016/j.proeng.2016.06.254 ◽

2016 ◽

Vol 147 ◽

pp. 613-617

Author(s):

Gerrit Thiele ◽

Patricia Kafka ◽

Stefan Litzenberger ◽

Anton Sabo

Keyword(s):

Muscle Activity ◽

Neck Muscle

Download Full-text

Attenuation of human neck muscle activity following repeated imposed trunk-forward linear acceleration

Experimental Brain Research ◽

10.1007/s00221-003-1466-9 ◽

2003 ◽

Vol 150 (4) ◽

pp. 458-464 ◽

Cited By ~ 64

Author(s):

Jean-Sébastien Blouin ◽

Martin Descarreaux ◽

Ariane Bélanger-Gravel ◽

Martin Simoneau ◽

Normand Teasdale

Keyword(s):

Muscle Activity ◽

Linear Acceleration ◽

Neck Muscle

Download Full-text

Head Movements and Neck Muscle Activity During Air Combat Maneuvering

Aerospace Medicine and Human Performance ◽

10.3357/amhp.5425.2020 ◽

2020 ◽

Vol 91 (1) ◽

pp. 26-31 ◽

Cited By ~ 1

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.

Download Full-text

Effect of triiodothyronine on the maxilla and masseter muscles of the rat stomatognathic system

Brazilian Journal of Medical and Biological Research ◽

10.1590/s0100-879x2011007500063 ◽

2011 ◽

Vol 44 (7) ◽

pp. 694-699

Author(s):

M.V. Mariúba ◽

F. Goulart-Silva ◽

S. Bordin ◽

M.T. Nunes

Keyword(s):

Stomatognathic System ◽

Masseter Muscles

Download Full-text

Improved neck posture and reduced neck muscle activity when using a novel camera based workstation for manual precision inspection tasks

Applied Ergonomics ◽

10.1016/j.apergo.2020.103147 ◽

2021 ◽

Vol 90 ◽

pp. 103147

Author(s):

Julia Gräf ◽

Klaus Mattes ◽

Kerstin Luedtke ◽

Bettina Wollesen

Keyword(s):

Muscle Activity ◽

Neck Muscle ◽

Precision Inspection ◽

Inspection Tasks

Download Full-text

Coherence of jaw and neck muscle activity during sleep bruxism

Journal of Oral Rehabilitation ◽

10.1111/joor.12932 ◽

2020 ◽

Vol 47 (4) ◽

pp. 432-440 ◽

Cited By ~ 3

Author(s):

Simone Gouw ◽

Angela Frowein ◽

Carlijn Braem ◽

Anton Wijer ◽

Nico H. J. Creugers ◽

...

Keyword(s):

Muscle Activity ◽

Sleep Bruxism ◽

Neck Muscle

Download Full-text

Relationship Between Sleep, Neck Muscle Activity, and Pain in Cervical Dystonia

Canadian Journal of Neurological Sciences / Journal Canadien des Sciences Neurologiques ◽

10.1017/s0317167100038233 ◽

1996 ◽

Vol 23 (4) ◽

pp. 285-290 ◽

Cited By ~ 38

Author(s):

Frank Lobbezoo ◽

Marc Thu Thon ◽

Guy Rémillard ◽

Jacques Y. Montplaisir ◽

Gilles J. Lavigne

Keyword(s):

Muscle Activity ◽

Cervical Dystonia ◽

Nrem Sleep ◽

Spinal Pain ◽

Spasmodic Torticollis ◽

Controlled Study ◽

Emg Activity ◽

Neck Muscle ◽

Upper Trapezius ◽

Before And After

AbstractObjective: The interactions between sleep, neck muscle activity, and cervical spinal pain were examined in a controlled study with nine patients suffering from idiopathic cervical dystonia (ICD; also referred to as spasmodic torticollis), and nine gender- and age-matched controls. Methods: From each participant, two all-night polysomnograms with additional electromyographic recordings from the sternocleidomastoid and upper trapezius muscles were obtained. The first night was for habituation to the laboratory environment; the second night for experimental data collection. Visual analogue scales were used to collect intensity and unpleasantness ratings of cervical spinal pain before and after the second sleep recording. Results: None of the standard sleep variables showed statistically significant differences between average values of both groups of participants. However, a significantly larger variance in sleep latency was obtained for the ICD patients. In general, abnormal cervical muscle activity decreased immediately when lying down without the intention to go to sleep. Subsequently, abnormal muscle contractions were gradually abolished in all ICD patients during the transition from relaxed wakefulness to light NREM sleep. Following this transition phase, no more abnormal EMG activity was found in any of our patients. Finally, cervical spinal pain intensity and unpleasantness were reduced by about 50% overnight. Conclusions: Both supine position and sleep can be associated with an improvement of symptoms of ICD, and this disorder does not induce any sleep perturbations.

Download Full-text