Posterior nucleus of vagus nerve
Nucleus posterior nervi vagi
- Latin synonym: Nucleus dorsalis nervi vagi; Nucleus vagalis dorsalis
- Synonym: Dorsal nucleus of vagus nerve; Dorsal vagal nucleus
- Related terms: Posterior nucleus of vagus nerve; Dorsal nucleus of vagus nerve
Definition
The posterior nucleus of vagus nerve, also known as the dorsal motor nucleus of the vagus, is a cluster of nerve cells located beneath the floor of the lower fourth ventricle, lateral to the hypoglossal nucleus. It is categorized as a parasympathetic and general visceral afferent nucleus, contributing to the formation of the vagus nerve along with the nucleus ambiguus and the nucleus of the tractus solitarius.
Afferent Connections:
The posterior nucleus of vagus nerve receives afferent fibers from the hypothalamus via descending autonomic pathways, as well as from the glossopharyngeal nerve, which participates in reflexes like the carotid sinus reflex.
Efferent Connections:
Efferent parasympathetic fibers from this nucleus travel long distances along the vagus nerve and its branches to innervate involuntary muscles of the bronchi, heart, esophagus, stomach, small intestine, and up to the distal third of the transverse colon.
References
Snell, R.S. (2010). ‘Chapter 11: The cranial nerve nuclei and their central connections and distribution’, in Clinical Neuroanatomy. (7th ed.) Philadelphia: Wolters Kluwer Health/Lippincott Williams & Wilkins, pp. 346, & 352-353.
