Cranial Nerves

There are 12 cranial nerves :

1. Olfactory - sensory - sense of smell

2. Optic - sensory - vision

3. Occulomotor - motor - supplies the medial rectus, inferior rectus, superior rectus, inferior oblique, which control eye movement plus the levator palpebrae superioris, and m. sphincter pupillae.

4. Trochlear - motor - supplies the lateral rectus muscle of the eye.

5. Trigeminal -(3 branches - Optic, Maxillary, Mandibular)Both sensory and motor - Receives sensation from the face and innervates the muscles of mastication.

6. Abducens - motor - supplies the superior oblique muscle of the eye, which abducts the eye.

7. Facial - both sensory and motor. motor innervation to the muscles of facial expression. Receives taste from the anterior 2/3 of the tongue, and provides secretomotor innervation to the salivary glands (except parotid) and the lacrimal gland.

8. Vestibulocochlear - sensory - hearing and balance - the vestibular branch carries impulses for equilibrium and the cochlear branch carries impulses for hearing.

9. Glossopharyngeal - Both sensory and motor - taste from the posterior 1/3 of the tongue, secretomotor innervation to the parotid gland, motor innervation to the stylopharyngeus (essential for tactile, pain, and thermal sensation)

10. Vagus - Both sensory and motor - Supplies branchiomotor innervation to most laryngeal and all pharyngeal muscles (except the stylopharyngeus, which is innervated by the glossopharyngeal); provides parasympathetic fibers to nearly all thoracic and abdominal viscera down to the splenic flexure; and receives the special sense of taste from the epiglottis. A major function: controls muscles for voice and resonance and the soft palate.

11. Spinal / accessory - Motor - supplies the trapezius and sternocleidomastoid

12. Hypoglossal - motor - motor innervation to the muscles of the tongue. Important for swallowing (bolus formation) and speech.