Nucleus ambiguus
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| Brain: Nucleus ambiguus | ||
|---|---|---|
| Transverse section of medulla oblongata below the middle of the olive. ("Nucleus ambiguus" labeled at center right.) | ||
| Nuclei of origin of cranial motor nerves schematically represented; lateral view. (Nucleus ambiguus visible at bottom right.) | ||
| Gray's | subject #187 779 | |
| NeuroNames | hier-762 | |
| Dorlands/Elsevier | n_11/12580164 | |
The nucleus ambiguus (literally "ambiguous nucleus") is a region of histologically disparate cells located just dorsal (posterior) to the inferior olivary nucleus in the lateral portion of the upper (rostral) medulla. This nucleus gives rise to the efferent motor fibers of the vagus nerve (CN X) terminating in the laryngeal and pharyngeal muscles, as well as to the efferent motor fibers of the glossopharyngeal nerve (CN IX) terminating in the stylopharyngeus.
The muscles supplied by the vagus (included with this is the cranial part of the accessory nerve), such as levator veli palatini, are also necessary to swallow properly. The vagus also supplies the upper part of the esophagus, and other parts of the pharynx and larynx.
As well as motor functions, nucleus ambiguus also contains the preganglionic neurons for the heart.
[edit] External links
- Medical Neurosciences discuss the nucleus ambiguus.
- GPnotebook -1664090053
