27 下列關於疑核（nucleus ambiguus）的敘述，何者正確？

 所發出之纖維支配咽內在肌群（intrinsic laryngeal muscles）

位於孤立核的背側

含有交感神經節前神經元

含有感覺神經元

this nucleus lies dorsal and lateral to the inferior olive.

Cells in nucleus ambiguus contain motor neurons associated with three cranial nerves

rostral pole =C.N. IX=glossopharyngeal;

middle part =C.N. X=vagus;

caudal pole =C.N. XI=spinoaccessory).

Axons arising from nucleus ambiguus pass laterally and slightly ventrally to exit the medulla just dorsal to the inferior olive.

These axons then course with the three cranial nervesIX (glossopharyngeal), X (vagus) and XI (spinoaccessory)to innervate the striated muscles of the soft palate, pharynx, larynx, and upper part of the esophagus.

Since these muscles have developed embryologically from branchial arches 3, 4 and 5, the cells that innervate them are called branchiomotor.

Remember, NUCLEUS AMBIGUUS is “SHARED” by three cranial nerves (IX, X, XI). The general pattern of motor innervation below does not have to be memorized.

IX stylopharyngeus muscle

X palatal muscles; levator veli palatini (with assistance from V for the tensor veli palatini; of little clinical significance), most of the pharyngeal muscles (with assistance from IX), laryngeal muscles and striated muscles of the esophagus-palatoglossus too!

XI laryngeal muscles (cranial portion)

THINK SOFT PALATE, PHARYNX, LARYNX

http://www.neuroanatomy.wisc.edu/virtualbrain/BrainStem/09NA.html

fantastic web site!