Cranial Nerves

Question 1

Which CNs enter the Cribiform Plate

Answer 1

CN I

Question 2

Which CNs enter the Optic Canal

Answer 2

CN II

Question 3

Which CNs enter/Exit the Superior Orbital Fossa

Answer 3

CN III, CN IV, CN VI and CNV1 (opthalmic)

Question 4

Which CNs enter/Exit the jugular Foramen

Answer 4

CN XI, CNX and CN XI

Question 5

Which CNs enter/Exit the Internal Acoustic Meatus

Answer 5

CNVII and CN VIII

Question 6

What are the three exits for the three branches of the trigeminal Nerve

Answer 6

V1 = Superior Orbital Fissure, V2 = Foramen Rotundum, V3 = Foramen Ovale

Question 7

Which CNs enter/Exit the Hypoglossal Foramen

Answer 7

CN XII

Question 8

What are the Nuclei in the Somatic Motor region of the brain stem and what are their levels

Answer 8

CN III (Midbrain), CN IV (Midbrain), CN VI (Pons) and CN XII (medulla)

Question 9

What are the Nuclei in the Brachial Motor region of the brain stem and what are their levels

Answer 9

CN V (Mastication-Pons), CNVII (Facial expression-Pons), CNIX (stylopharangeus - Medulla), CN X (Levator palatine Swallowing - Medulla) CN XI (Neck Muscles -Spinal Chord)
CNXI and CNX make up the Nucleus Ambiguus

Question 10

What are the Nuclei in the Automatic/Visceral Motor region of the brain stem and what are their levels

Answer 10

CN III (Iris/Cilliary PNS - Midbrain known as the Edgar-Westfall nuclei), CN VII (Submandibular/Sublingual -Pons), CN IX (parotid), CN X (Peristalis of oesophagus - Medulla)

Question 11

What are the Nuclei in the Visceral Afferants region of the brain stem and what are their levels

Answer 11

Known as the Solitary Nuclues (consists of CNVII, CNIX and CNX and expands the medulla) the rostral section contains the gustatory nuclei of taste from VII (anterior 2/3rds), IX (posterior 1/3rd) and vagus (epiglottis). The caudal section will recieve input from the XI (carotid bodies), X (aortic arch) interms of baroceptors and chemoceptors.

Question 12

What are the Nuclei in the Somatic Afferants region of the brain stem and what are their levels

Answer 12

CNV (MidBrain, Pons and spanning medulla with CNVII, XI and X) CN V involved with touch on face and on anterior 2/3rds of the tongue. CN VII? CNIX for touch to the tongue and Gag reflex, CN X for regions in the larynx and pharynx

Question 13

What are the Nuclei in the Special Afferants region of the brain stem and what are their levels

Answer 13

CN XIII for hearing and for balance, nucleus is in the pons/medulla

Question 14

Nuclei Ambiguus Composes

Answer 14

CNXI and CN X (Brachial Motor) in which XI innervates Stylopharangeus and CN X innervates levator Palatini

Question 15

Which CNs innervate the Eyelid

Answer 15

CN III for Levator papillae and CN VII for Orbiocularis Oculi

Question 16

CNs innervating Glands

Answer 16

CN IX for the Parotid Gland, CNVII for sublingual and Submandibular and Lacrimal glands.

Question 17

5 branches of the Facial Nerve

Answer 17

Temporal, Zygomatic, Buccal, Mandibular, Cervical

Question 18

Movement of the Tongue

Answer 18

CNXII (except palatoglossus by CNX)

Question 19

Muscles innervated by CNXI

Answer 19

Sternoclasomastoid (Nodding) and Upper 1/3rd of Trapezius (Shrugging)

Question 20

Describe Papillae, corneal and gag reflexes

Answer 20

Papillae (CNII and CN III of midbrain), Corneal (CNV and CN VII of Pons) and Gag (CNIX and CNX of medulla)

Question 21

What are the three CNV nuclei in the Somatic Touch Afferent region of the brain stem and what is their function

Answer 21

The Mesencephalic (Face proprioception), The cheif (light touch and jaw proprioception) and the Spinal trigeminal (Touch, pain and temperature)

Question 22

What is the corticobulbar tract

Answer 22

Motor Tract from the cortex to the CN nuclei in the brain stem (excluding Occulomotor muscles) and they will have both bilateral innervation except CNVII (lower face) and CNXII which is just contralateral