Extrinsic muscles of tongue namely genioglossus
, hyoglossus, styloglossus and palatoglossus are responsible for positioning the tongue in the oral cavity.
Reist, "Acute effects of paroxetine on genioglossus
activity in obstructive sleep apnea," SLEEP, vol.
causes the tongue to move forward and downward so that it is held away from the soft palate; therefore, the pressure on the soft palate is released, and in this way, it moves anteriorly and superiorly, and thus produces an increase in the velopharyngeal volume, which may be more apparent if the tongue moves more forward (Figure 2) .
In this study, we established a HIF-1a knockout (KO) mice model and applied the NGS-based RAN-sequencing (RNA-seq) method to carry out a transcriptional analysis in genioglossus
of both HIF-1a -KO mice and littermate wild-type (WT) mice.
During the apnea episode, the increase in partial pressure of carbon dioxide (PCO2) and in the breathing effort result in a stimulation of the Reticular Activating System and microarousals are generated to activate the contraction of the PDMs (primordially the genioglossus
) to reinitiate the circulation of air through the upper airway.
Ringler et al., "Phenylephrine-induced hypertension acutely decreases genioglossus
EMG activity in awake humans," Journal of Applied Physiology, vol.
Uvulopalatopharyngoplasty and inferior sagittal mandibular osteotomy with genioglossus
advancement for treatment of obstructive sleep apnea.
While there are some lateral attachments to the hyoid bone below, the largest portion of the tongue muscle (the genioglossus
) loops back to the front under the tongue blade and attaches to the inside back of the chin.
A number of surgeries are utilized to treat patients with OSA due to hypopharyngeal obstructions, including: partial glossectomy, genioglossus
advancement, lingual tonsillectomy, and submucosal minimally-invasive lingual excision (SMILE).
Upper airway response to electrical stimulation of the genioglossus
in obstructive sleep apnea.
 demonstrated that, after sleep onset, there was a greater decrease in genioglossus
muscle activity and a greater increase in UA resistance in men than in women, thereby increasing the susceptibility to UA occlusion.
However, two other studies demonstrated that the airway did not affect the electromyographic activity of the genioglossus
muscle in normal individuals, but other pharyngeal dilator muscles have not been studied [31, 32].