Table 1.
Major Orofacial Muscles Whose Contraction Affects the Lumen and Patency of the Upper Airway
| Muscle name (cranial nerve providing motor innervation) | Presumed action on upper airway; (bold indicates airway-dilating action) | Typical pattern of activity during wakefulness (I, inspiratory; E, expiratory; t, tonic) | References describing sleep-wake activity in different species (hh, healthy humans; OSAh-, OSA patients; c, cat; d, dog; g, goat; l, lamb; r, rat) |
|---|---|---|---|
| Alae nasi (VII) | Widens nares | I + t | hh: 582,591 |
| E + t | r: 102,491 | ||
| Tensor veli palatini (V) | Moves soft palate up | t (+ I) | hh: 375,541,601 |
| t (+I) | OSAh: 20,74 | ||
| Levator veli palatini (V) | Moves soft palate up | I + t (or silent) | hh: 465,542 |
| Palatopharyngeus (XI) | Moves soft palate down; pharynx up | ||
| Palatoglossus (XII) | Moves tongue up and posterior | I + t | hh: 542 |
| Styloglossus (XII) | Moves tongue up and posterior | t (+ I) | OSAh: 111 |
| Genioglossus (XII) | Moves tongue down and anterior | I + t | hh: 35, 40, 91,280,464,511,541,592,601 |
| I + t | OSAh: 20, 74,111,120,246,247,346,378,465 | ||
| I + t | c: 188,437 | ||
| I + t | d: 225,414,455 | ||
| I + t | g: 400,401 | ||
| I + t or t | r: 82,233,316,340,360,446,520 | ||
| Hyoglossus (XII) | Moves tongue down and posterior | t | OSAh: 111 |
| Stylopharyngeus (IX) | Moves up and widens pharynx | ||
| Pharyngeal constrictors (X) | Stiffen posterior pharyngeal wall; reduce pharyngeal lumen; move hyoid bone posterior | E or silent | hh: 465 |
| E | OSAh: 281 | ||
I 
|
r: 493 | ||
| Digastric anterior (VII) | Moves hyoid bone anterior | t | c: 407 |
| Geniohyoid (XII) | Moves tongue down; hyoid bone up | I + t | hh: 589,590 |
| t | r: 446 | ||
| Mylohyoid (V) | Stiffens floor of the mouth | ||
| Omohyoid (C1-3 via XII) | Moves hyoid bone down | ||
| Thyrohyoid (C1-3 via XII) | Brings closer hyoid bone and thyroid cartilage | ||
| Sternohyoid (C1-3 via XII) | Moves hyoid bone down | I | d: 191 |
| I | r: 341,493 | ||
| Sternothyroid (C1-3 via XII) | Moves thyroid cartilage down | I | r: 341 |
| Posterior cricoarytenoid (X) | Abducts vocal folds | I + post-I +t | hh: 282 |
| I + t | c: 188 | ||
| I + t | l: 253 | ||
| I + t | r: 342,492 | ||
| Lateral cricoarytenoid (X) | Adducts vocal folds | E | r: 342,492 |
| Arytenoid (X) | Adducts vocal folds | E | hh: 278 |
| I/E + t | r: 342 | ||
| Thyroarytenoid (X) | Relaxes vocal folds | E + t | hh: 279 |
| I or silent | l: 253 | ||
| E | r: 342 | ||
| Cricothyroid (X) | Tenses vocal folds | I + t | hh: 284 |
| I + t | l: 253 | ||
| I or I/E | r: 342,492 |
Note. Muscles are listed together with the source of their innervation, possible role in the control of upper airway patency, prevailing pattern of spontaneous activity during quiet wakefulness, and references describing their sleep-wake activity in different species.