Facts Friday: CATaloging the Cranial Nerves - The Vagus 10
Making a fashionably late appearance in our series, the Vagus is the topic today. If it seems like the Vagus has her nose in everything… that’s because she does. It can be easy to just think of the Vagus as a bossy diva… but really she’s the workhorse behind everything. (Think Meryl Streep in The Devil Wears Prada.)
The Vagus provides motor innervation for (y’all ready for this?): the superior, middle and inferior constrictors, soft palate muscles-palatoglossus, palatopharyngeus, musculus uvulae, and levator palatini (she allows the trigeminal to take of the tensor veli palatini), the salpingopharyngeus, and allllll the intrinsic muscles of the larynx- lateral cricoarytenoids, transverse arytenoid, posterior cricoarytenoids, oblique arytenoids, aryepiglottics, cricothyroids, thyroarytenoids, and vocalis. Sheeeeesh…
She also collects sensory info at the mucous membranes of the epiglottis, valleculae, , aryepiglottic folds, and almost all of the larynx; below the vocal folds, sensory taste to the epiglottis and general sensation to the posterior tongue, velum, distal part of the pharynx, and the UES.
Because the Vagus is so very complex, it can be difficult to assess clinically. Examining the soft palate for symmetry, listening to the voice for inconsistencies in loudness, pitch and control can be general, but since damage to the Vagus can impair airway closure, cough strength, UES function and sensation of aspiration, this patient really needs an instrumental to properly assess the physiological impairment.
The Vagus is obviously incredibly important to swallowing… quite honestly if I were that important, I’d be a bit of a diva too. See below for further reading: