Cranial Nerves

Question 1

Occulomotor Nerve

Answer 1

Arises: midbrain.
Functional: somatic motor and visceral motor.
Nuclei: occulomotor, Edinger-Westphal.
Structures: medial, superior, inferior rectus; inferior oblique, ciliary and sphincter pupillae muscles.

Question 2

Trochlear Nerve

Answer 2

Arises: dorsal surface of midbrain.
Functional: general somatic motor.
Nuclei: trochlear nucleus.
Structures: superior oblique muscle (eye down and out)
Note: decussates in caudal midbrain.

Question 3

Abducens Nerve

Answer 3

Arises: pontomedullary junction.
Functional: general somatic motor.
Nuclei: abducens nucleus.
Structures: lateral rectus (moves eye laterally).

Question 4

Hypoglossal Nerve

Answer 4

Arises: medulla, between pyramid and olive.
Functional: somatic motor.
Nuclei: hypoglossal nucleus.
Structures: all but 1 intrinsic muscles of tongue.

Question 5

Accessory Nerve

Answer 5

Arises: caudal medulla (cranial root) and cervical spine (spinal root).
Functional: branchiomotor.
Nuclei: accessory nucleus.
Structures: sternocleidomastoid and trapezius.
Note: lower motor neuron.

Question 6

Vestibulocochlear Nerve

Answer 6

Arises: pontomedullary junction.
Functional: special sensory.
Nuclei: vestibular nuclei, cochlear nuclei.
Structures: cochlea, vestibular apparatus.

Question 7

Facial Nerve - Motor

Answer 7

Arises: pontomedullary junction.
Functional: branchiomotor, visceral motor.
Nuclei: facial nucleus (branchio), superior salivatory nucleus (visceral).
Structures: muscles of facial expression, stapedius (in ear) (facial), major glands of head (lacrimal, mucosal, salivary) (s. sal. nuc.).
Note: lower motor neuron.

Question 8

Facial Nerve - Sensory

Answer 8

Arises: pontomedullary junction.
Functional: special visceral sensory, somatic sensory.
Nuclei: solitary nucleus (special visceral), spinal trigeminal (general).
Structures: taste from anterior 2/3rd of tongue (Sol), external ear skin (spinal trigeminal).

Question 9

Trigeminal Nerve - Motor

Answer 9

Arises: lateral sides of pons.
Functional: branchiomotor.
Nuclei: trigeminal motor.
Structures: jaw muscles (mastication), tensor tympani (in ear).

Question 10

Trigeminal Nerve - Sensory

Answer 10

Arises: lateral sides of pons.
Functional: somatic sensory.
Nuclei: mesencephalic, principle and spinal trigeminal nuclei.
Structures: proprioception from jaw (mesencephalic), touch and vibration in head (principle), pain/temperature in head (spinal).

Question 11

Branches of Trigeminal Nerve

Answer 11

V1 Opthalmic: enters via superior orbital fissure, anterior scalp to nose (incl. inside nose).
V2 Maxillary: enters via foramen rotundum, nasal cavity to upper jaw.
V3 Mandibular: enters via foramen ovale, lower jaw, taste in anterior 2/3rd of tongue.

Question 12

Vagus Nerve - Motor

Answer 12

Arises: medulla.
Functional: branchiomotor, visceral motor.
Nuclei: nucleus ambiguus, dorsal motor nucleus.
Structures: larynx, pharynx (speech and swallowing) and one tongue muscle (Ambiguus), thorax and abdominal viscera (dorsal motor).

Question 13

Vagus Nerve - Sensory

Answer 13

Arises: medulla.
Functional: visceral sensory, special visceral sensory, somatic sensory.
Nuclei: solitary nucleus, spinal and principle trigeminal nuclei.
Structures: sensory from thorax and abdominal viscera, larynx, pharynx, oesophagus, taste from epiglottis (solitary), ear, meninges (spinal, principle trigeminal).

Question 14

Glossopharyngeal Nerve - Motor

Answer 14

Arises: medulla.
Functional: branchiomotor, visceral motor.
Nuclei: nucleus ambiguus, inferior salivatory nucleus.
Structures: one pharynx muscle (speaking and swallowing) (ambiguus), one salivary gland (inferior salivatory).

Question 15

Glossopharyngeal Nerve - Sensory

Answer 15

Arises: medulla.
Function: special visceral sensory, visceral sensory, somatic sensory.
Nuclei: solitary nucleus, spinal trigeminal.
Structures: taste in posterior 1/3rd of tongue, baro- and chemoreceptors (solitary), somatosensation in posterior 1/3rd of tongue and upper pharynx (spinal trigeminal).