Cranial Nerve Handout

Question 1

What n. leaves cranial cavity via cribiform foramina?

Answer 1

Olfactory n.

Question 2

What n. leaves cranial cavity via optic canal?

Answer 2

Optic n.

Question 3

What nn. leave cranial cavity via orbital fissure?

Answer 3

1. Oculomotor n. (3)
2. Trochlear n. (4)
3. Opthalmic branch of trigeminal (V1)
4. Aducens (6)

Question 4

Trigeminal n. passes through what in cranial cavity before trifurcating?

Answer 4

Trigeminal canal

Question 5

What n. leaves cranial cavity through oval foramen?

Answer 5

Mandibular branch of trigeminal

Question 6

What n. leaves cranial cavity through round foramen?

Answer 6

Maxillary branch

Question 7

What nn. enter internal acoustic meatus?

Answer 7

Facial (7) and vestibulocochlear (8)

Question 8

What n. leaves cranial cavity through stylomastoid foramen?

Answer 8

Facial

Question 9

What nn. enter jugular foramen to exit cranial cavity via tympano-occipital fissure?

Answer 9

9-11 (glossopharyngeal, vagus and accessory)

Question 10

Olfactory n. comes off of brain where?

Answer 10

Olfactory lobe

Question 11

Oculomotor n. comes off of brain where?

Answer 11

Just cd. to pituitary (small)

Question 12

Trocheal n. comes off of brain where?

Answer 12

Dorsal brainstem between cerebrum and cerebellum

Question 13

What nn. come off at lateral edge of trapezoid bodies?

Answer 13

5, 7-10 (5 and 8 are big)

Question 14

Which n. does not emerge from cranial cavity?

Answer 14

Vestibulochoclear n. (8)

Question 15

Function of olfactory n.

Answer 15

Olfaction (SVA)

Question 16

Function of optic n.

Answer 16

Vision (SSA)

Question 17

Functions of oculomotor n.

Answer 17

Motor to: (GSE)

1. Ventral oblique m.
2. Dorsal, ventral, medial rectus mm. (all except lateral rectus m.)
3. Levator palpebrae superioris m.

Parasympathetic GVE to:

1. Sphincter mm. of iris
2. Ciliary m.

Question 18

Trochlear function

Answer 18

Motor to dorsal oblique m. (GSE)

Question 19

3 branches of trigeminal n.

Answer 19

1. Ophthalmic br.
2. Maxillary br.
3. Mandibular br.

Question 20

Function of ophthalmic br.

Answer 20

GSA (sensory) to and around eye

Question 21

Function of maxillary br.

Answer 21

GSA (sensory) to and around superior arcade and lip

Question 22

Functions of mandibular br.

Answer 22

1. GSA to and around inferior arcade, lip and tongue

2. SVE to mm. of mastication except cd. half of digastricus m.

Question 23

Function of abducens n.

Answer 23

GSE to:

1. Lateral rectus m.
2. Retractor bulbi mm.

Question 24

Functions of facial n.

Answer 24

Motor (SVE) to:

1. Mm. of facial expression
2. Cd. half of digastricus m.
3. SVA taste sensation to rostral 2/3 of tongue

Parasympathetic GVE to:
4-6. Lacrimal, nasal and palatine glands
7-8. Mandibular and sublingual glands

Sensory (GVA) to:

9. Soft palate
10. Nasopharynx

Question 25

Function of vestibulocochlear n.

Answer 25

Balance and audition (SSA)

Question 26

Functions of glosopharyngeal n.

Answer 26

1. SVA (taste sensation) from cr. 1/3 of tongue

Parasympathetic GVE to:

2. Parotid sg.
3. Zygmoatic sg.

Sensory (GVA) to:

4. Pharynx
5. Carotid sinus

Motor (SVE) to:
6. Pharyngeal mm.

Question 27

Function of accessory n.

Answer 27

SVE (motor) to:

1. Trapezius m.
2. Sternocephalicus m.
3. Brachiocephalicus m
4. Omotransversius m.

Question 28

Function of hypoglossal n.

Answer 28

GSE (motor) to extrinsic and intrinsic mm. of tongue

Question 29

Functions of vagus n.

Answer 29

GVE (motor) to:

1. Smooth m. and glands of resp. and digestive systems
2. Heart

GVA (sensory) to respiratory and digestive systems

SVE (motor) to:

3. Pharynx
4. Larynx

SVA (taste) to pharynx

GSA (sensory) from external auditory canal