cranial nerve

Introduction

One of 12 nerves that emerge from or enter the cranium or skull.

* image

Function

sensory & motor functions of the cranial nerves*

#	Name	cranial nerve type
1	olfactory	SVA
2	optic	SSA
3	oculomotor	GSE, GVE
4	trochlear	GSE
5	trigeminal	GSA, GSE
6	abducent	GSE
7	facial	GSA, GVA, SVA, GSE, SVE
8	vestibulocochlear	SSA
9	glossopharyngeal	GSA, GVA, SVA, SVE, GVE
10	vagus	GSA, GVA, SVA, SVE, GVE
11	accessory	GSE
12	hypoglossal	GSE

*Key to table:

* SSA: special somatic afferent

• includes the special senses of vibration, hearing, balance

* GSA: general somatic afferent

• carries general sensation from skin & mucous membrane

* GVA: general visceral afferent

• carries visceral sensation from parotid gland, carotid body & carotid sinus, middle ear, pharynx, larynx, trachea, bronchi, lungs, heart, esophagus, & intestine to the left colic flexure (splenic flexure)

* SVA: special visceral afferent

• includes taste & smell

* GSE: general somatic efferent

• supplies muscles derived from cranial myotome region of the embryonic somites (muscles of tongue, orbit, jaw)

* SVE: special visceral efferent

• supplies muscles derived from the embryonic branchial arches (muscles of the larynx & pharynx)

* GVE: general visceral efferent

• consists of the cranial parasympathetic system
• cranial nerve autonomic fibers coming out of the CNS are all parasympathetic (cranial nerve 3, cranial nerve 7, cranial nerve 9, cranial nerve 10)

More general terms

• nervous system structure

More specific terms

• cranial nerve VI; abducens nerve (CN VI)
• facial nerve (CN VII)
• glossopharyngeal nerve (CN IX)
• hypoglossal nerve (CN XII)
• oculomotor nerve (CN III)
• olfactory nerve (CN I)
• optic nerve (CN II, ON)
• spinal accessory nerve (CN XI)
• trigeminal nerve (CN V)
• trochlear nerve (CN IV)
• vagus nerve (CN X)
• vestibulocochlear nerve (CN VIII)

Additional terms

• cranial nerve nucleus