Related Experiment Video
Updated: Jun 6, 2026

In Vivo Evaluation of the Mechanical and Viscoelastic Properties of the Rat Tongue
Published on: July 6, 2017
Activation pattern masticatory muscles in dysphonics woman
D Rodrigues-Bigaton1, A Schwarzenbeck, K C S Berni
1Methodist University of Piracicaba, São Paulo, Brazil. drodrigues@unimep.br
Purpose:
To evaluate the pattern of activation of the masticatory muscles in dysphonic women.
Methods:
Seventeen women was divided into two groups: experimental group with 10 dysphonic women (33.6 +/- 8.0) and control group with 7 healthy women (25 +/- 5,19). The Electromyography exam of the left (LM) and right (RM) masseter muscles, anterior portion of the right (RT) and left (LT) temporal, and suprahyoid (SH) was performed by using electrodes of simple distinguishing surface.
Results:
With the mandible postural position at rest, all the muscles presented increased electromyography activity compared to the control group (p < 0.05). As for the mandible elevator muscles, the RM experimental group presented significantly decreased electromyography activity (p < 0, 05) and the SH increased (p < 0.05) compared to the control group. For the rest of the muscles, there was no significantly difference between the groups. It was verified that the experimental group presented higher co-contraction of the mandible depressed muscles in relation to contraction of the RT LT, RM and LM, as compared to the control group (p < 0.05).
Conclusions:
Dysphonic women present alteration of the activation patterns of the masticatory muscles.
Related Concept Videos
Deglutition
Swallowing can be divided into three stages: the voluntary phase, the pharyngeal phase, and the esophageal phase. Although the...
Muscles for Facial Expressions
Assessment of the Mouth
Mouth Inspection
The inspection begins with visually examining the mouth for symmetry, color, and size.
Larynx
Anatomy of the Larynx
The larynx consists of various components, including cartilage, muscles, and vocal cords. Its structure includes three large unpaired cartilages—the thyroid, cricoid, and epiglottis—and three smaller paired cartilages—the arytenoids, corniculates, and...
Pharynx
Nasopharynx
The nasopharynx, bordered by the conchae of the nasal cavity, serves exclusively as an air conduit. In its superior region, the pharyngeal tonsils or adenoids are located. These tonsils are clusters of lymphoid reticular tissue akin to a lymph node. The precise...
Suctioning the Oropharyngeal Airway
After assembling the equipment, the nurse should practice hand hygiene and don appropriate PPE according to infection control guidelines to avoid the...
