Cranial Nerves

Question 1

Which cranial nerves have sensory functions?

Answer 1

• Olfactory
• Optic
• Vestibulocochlear

Question 2

Which cranial nerves have motor functions?

Answer 2

• Oculomotor
• Trochlear
• Abducens
• Accessory
• Hypoglossal

Question 3

Which cranial nerves have mixed function?

Answer 3

• Trigeminal
• Facial
• Glossopharyngeal
• Vagus

Question 4

Where does the olfactory nerve (CNI) exit the cranium?

Answer 4

Through the cribriform plate of the ethmoid bone

Question 5

Where does the optic nerve (CNII) exit the cranium?

Answer 5

Through the optic canal

Question 6

Where does the oculomotor nerve (CNIII) exit the cranium?

Answer 6

Superior orbital fissure

Question 7

Where does the trochlear nerve (CNIV) exit the cranium?

Answer 7

Superior orbital fissure

Question 8

Where does the trigeminal nerve (CNV) exit the cranium?

Answer 8

• Superior orbital fissure
• Foramen rotundum
• Foramen ovale

Question 9

Where does the abducens nerve (CNVI) exit the cranium?

Answer 9

Superior orbital fissure

Question 10

Where does the facial nerve (CNVII) exit the cranium?

Answer 10

Internal accoustic meatus

Question 11

Where does the vestibulocochlear nerve (CNVIII) exit the cranium?

Answer 11

Internal accoustic meatus

Question 12

Where does the glossopharyngeal nerve (CNIX) exit the cranium?

Answer 12

Jugular foramen

Question 13

Where does the vagus nerve (CNX) exit the cranium?

Answer 13

Jugular foramen

Question 14

Where does the accessory nerve (CNXI) exit the cranium?

Answer 14

Jugular foramen

Question 15

Where does the hypoglossal nerve (CNXII) exit the cranium?

Answer 15

Hypoglossal canal

Question 16

Which neurons are contained in the trigeminal motor nucleus?

Answer 16

Motor neurons that innervate the muscles of mastication and the other muscles served by the trigeminal nerve (mylohyoid, anterior belly of digastric, tensor veli palatini and tensor tympani).

BRANCHIOMOTOR

Question 17

Where does the spinal accessory nerve arise from?

Answer 17

The cervical spinal cord

Question 18

Which sensation does the mesencephalic nucleus receive?

Answer 18

Proprioceptive information from chewing muscles

Question 19

Which sensory input does the pontine trigeminal nucleus receive?

Answer 19

Discriminitive touch and vibration

Question 20

Which input does the spinal nucleus receive?

Answer 20

Pain and temperature

Question 21

Describe the spinal nucleus of trigeminal

Answer 21

Long column of neurons that stretches from the midbrain down to the upper 2 segments of the cervical spinal cord.

It has 3 parts and is separated by function.

Question 22

What are the 3 parts of the spinal trigeminal nerve?

Answer 22

1. Pars oralis
2. Pars interpolaris
3. Pars caudalis

Question 23

Aside from trigeminal, which cranial nerves have an input into the spinal trigeminal nucleus?

Answer 23

• VII
• IX
• X
• Have a small sensory input for general sensation and pain and temperature around the ear.

Question 24

Which cranial nerves input to the superior and inferior salivatory nuclei?

What are they responsible for?

Answer 24

• Cranial nerves VII and IX
• Parasympathetic efferents to ganglia of salivary glands and pterygopalatine ganglion.
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Question 25

Which cranial nerves input to the nucleus ambiguus?

What are they responsible for?

Answer 25

• CNIX and CNX
• Motor efferents to muscles of the pharynx, larynx and upper oesophagus

Question 26

Which cranial nerves have input into the solitary nucleus?

What are they responsible for?

Answer 26

• CNVII, CNIX and CNX
• Taste and visceral sensory information

Question 27

Describe the solitary nucleus

Answer 27

• Extends in a ‘V’ shape from upper to mid medulla
• Has 2 parts:
  
  • Gustatory nucleus
  • Commissural nucleus

Question 28

Which CNs are the complex cranial nerves?

Answer 28

• Facial nerve (VII)
• Glossopharyngeal (IX)
• Vagus (X)

Question 29

What are the functions of the facial nerve?

Answer 29

• Motor - muscles of facial expression, stapedius (SVE).
• Parasympathetic innervation to the pterygopalatine and submandibular ganlgia (GVE).
• Taste - anterior 2/3 of the tongue via the chorda tympani (SVA).
• Somatosensation to a small region around the ear (GSA).

Question 30

What are the functions of the glossopharyngeal nerve?

Answer 30

• Tactile sense, pain and temperature sense from the posterior 1/3 of the tongue, pharyngotympanic tube and uper pharynx (and small area around the ear) (GSA).
• Taste - posterior 1/3 of the tongue (SVA).
• Visceral sensation from the carotid sinus and carotid body (GVA).
• Motor - stylopharyngeus (SVE).
• Parasympathetic innervation to the otic ganglion(parotid gland) (GVE).

Question 31

What are the functions of the vagus nerve?

Answer 31

• Parasympathetic innervation to the ganglia serving the thoracic and abdominal viscera (GVE).
• Motor - striated muscle of the pharynx and larynx (accessory nerve also contributes to this function) (SVE).
• Tactile sense, pain and temperature sense from the lower pharynx, larynx, oesophagus, dura (pain) and a small area around the ear (GSA).
• Visceral afferents from the aorta, lung, gut etc. (GVA).
• Tasta - epiglottis (SVA).