Cranial nerves

Question 1

Name this Cranial nerve + function.

Answer 1

Optic nerve.

• Vision.

Question 2

Name the cranial nerve and function[3 marks].

What does it control[4 marks].

Answer 2

Oculomotor nerve.

• Controls 4/6 extraocular muscles:
  
  • inferior rectus, superior rectus, medial rectus and inferior oblique.
  • Function:
    
    • ​Elevation of eyelid, pupillary constriction and focusing of the lens.

Question 3

Name this Cranial nerve and state its function.

Answer 3

Trochlear nerve(CNIV).

• Controls the superior oblique( extraocular muscle).
  
  • moves the eye up and out.

Question 4

Name the cranial nerve, states its function and divisions.

Answer 4

Trigeminal nerve(CN V):

• Sensory and motor control over muscles of mastication(chewing). 3 divisions:
• Sensory: Opthalamic division and maxillary.
• Motor and sensory: mandibular division.

Question 5

Name the Cranial nerve and state its function.

Answer 5

Abducens nerve(CN VI):

• Controls the Lateral rectus( extraocular muscle).

Moves pupil away from the midline.

Question 6

Name this cranial nerve and state its functions[3 marks].

Answer 6

Facial nerve.

• Motor control over muscles to facial expression.
• Taste of *2/3 anterior of the tongue*.
• Salivary glands:
  
  • submandibular & sublingual.
  • Lacrimal glands.
  • glands of the palate + Nasal gland.

Question 7

Name this Cranial nerve and state its function.

Answer 7

Vestibulocochlear nerve(CN VIII).

• Split into 2 nerves:
  
  • Vestibular nerve: movement and position of the head.
  • Cochlear nerve: auditory information.

Question 8

Name this Cranial nerve and state its function.

Occurrence in palsy within this nerve as a result of MS.

Control of what muscles for motor function?

Answer 8

Glossopharyngeal nerve(CN IX).

• Provides taste sensation to posterior 1/3 of the tongue.
• Taste and a general sensation of poster 3rd.

Motor functions:

• Controls the _Stylopharyngeal muscle_: widens and shortens the pharynx and elevates larynx during swallowing.

MS:

• Absent general taste and sensation in posterior 1/3 of tongue.

Question 9

Name this cranial nerve and state its function.

The difference in sensory and motor function.

Answer 9

Vagus nerve(CN X).

• Visceral sensation to the heart and abdominal viscera.
• Provides sensory taste to the root of the tongue.

Motor function:

• Muscles of Pharynx, soft palate , larynx. and elevation of uvula( ipsi.

Tip: behind the Hypoglossal nerve.

Question 10

Name this Cranial nerve and state its function.

areas of control?

Answer 10

Accessory nerve(CN XI).

• Motor control of sternocleidomastoid muscle and trapezius muscle.

Sternocleidomastoid:

• Turning of the head.

Trapezius muscles:

• shrugging of shoulders.

Question 11

Name this Cranial nerve and state its function.

Answer 11

Hypoglossal nerve.

• Somatic efferent(motor) nerve.
• Innervates the intrinsic and extrinsic pathway muscles of the tongue.
• Damage to hypoglossal nerve:
  
  • Protrusion and deviation of the tongue towards the area of damage.
  • Muscle wasting and twitching.