The cranial nerves are twelve paired nerves arising from the brain and brainstem. They mostly supply the head and neck, with additional innervation of thoraco-abdominal structures. Cranial nerves have sensory, motor, or mixed functions and are numbered 1 to 12. Each plays a role in sensation, movement, and autonomic control in the head and neck.
Summary
Number | Name | Type | Function | Skull Exit | Origin |
|---|---|---|---|---|---|
1 | Olfactory | Sensory | Smell | Cribriform plate | Cerebrum |
2 | Optic | Sensory | Vision | Optic canal | Cerebrum |
3 | Oculomotor | Motor | Eye movement, pupillary constriction, raising eyelid | Superior orbital fissure | Midbrain |
4 | Trochlear | Motor | Eye movement (superior oblique) | Superior orbital fissure | Midbrain |
5 | Trigeminal | Both | Facial sensation, muscles of mastication | 5a: superior orbital fissure; 5b: foramen rotundum; 5c: foramen ovale | Pons |
6 | Abducens | Motor | Eye abduction (lateral rectus) | Superior orbital fissure | Pons |
7 | Both | Facial expression, taste anterior 2/3 of tongue, parasympathetics | Internal acoustic meatus to stylomastoid foramen | Pons | |
8 | Vestibulocochlear | Sensory | Hearing and balance | Internal acoustic meatus | Pons |
9 | Glossopharyngeal | Both | Swallowing, taste posterior 1/3 of tongue | Jugular foramen | Medulla |
10 | Vagus | Both | Voice production, swallowing, parasympathetics | Jugular foramen | Medulla |
11 | Accessory | Motor | Head, neck and shoulder movements | Jugular foramen | Medulla |
12 | Hypoglossal | Motor | Tongue movements | Hypoglossal canal | Medulla |