Cranial Nerve Components

Question 1

CN III (Occulomotor)

Contributing Nuclei (2)

Nuclei Type/Functions

Answer 1

• Occulomotor Nucleus
  
  • Somatomotor
  • Muscles of eye + eyelid opening
• Edinger-Westphal Nucleus
  
  • Preganglionic Parasympathetic
  • Pupil diameter and lens shape

Question 2

CN IV (Trochlear)

Contributing Nuclei (1)

Nuclei Type/Functions

Answer 2

• Trochlear Nucleus
  
  • Somatomotor LMNs
  • One muscle of eye - Superior Oblique
• NOTE: Only nucleus/CN to cross AND exit dorsally

Question 3

CN V (Trigeminal)

Contributing Nuclei (4)

Nuclei Type/Functions

Answer 3

• Trigeminal Motor Nucleus
  
  • Branchial Motor LMNs
  • Muscles of mastication
  • Tensor Timpani in middle ear
• Mesencephalic Nucleus V
  
  • Somatosensory
  • Unconscious proprio of Jaw
• Chief Sensory Trigeminal Nucleus
  
  • Somatosensory
  • Light touch/pressure of face
  • Light touch/pressure of ant. 2/3 of tongue
• Spinal Nucleus V
  
  • Somatosensory
  • Pain/temp of face
  • Pain/tmep of ant. 2/3 of tongue

Question 4

CN VI (Abducens)

Contributing Nuclei (1)

Nuclei Type/Functions

Answer 4

• Abducens Nucleus
  
  • Somatomotor
  • Lateral Rectus eye muscle
  • Runs interneurons to Medial Rectus of opposite eye

Question 5

CN VII (Facial)

Nerve Roots (2)

Contributing Nuclei (4)

Nuclei Type/Functions

Answer 5

• Nerve roots
  
  • Motor (medial - facial nucleus)
  • Intermediate (lateral - all else)
• Facial Nucleus (motor nerve root)
  
  • Branchial Motor LMNs
  • Muscles of facial expression
  • Strapedius (middle ear)
• Spinal Nucleus V
  
  • Somatosensory
  • Pain from ear
• Solitary Nucleus
  
  • Viscerosensory
  • Taste of ant. 2/3 of tongue
• Superior Salivatory Nucleus
  
  • Visceromotor Preganglionic Parasympathetic
  • Submandibular and sublingual salivary glands
  • Lacrimal glands

Question 6

CN IX (Glossopharyngeal)

Contributing Nuclei (4)

Type/Function

Answer 6

• Nucleus Ambiguous
  
  • Branciomotor (LMNs)
  • One muscle that elevates pharynx during swallowing (stylopharyngeus)
• Inferior Salivatory Nucleus
  
  • Visceromotor (preganglionic parasympathetic)
  • Parotid Gland
• Solitary Nucleus
  
  • Viscerosensory
  • Taste from post. 1/3 of tongue
• Spinal Nucleus of V
  
  • Somatosensory
  • Pain and temp of ear, post. 1/3 of tongue and pharynx

Question 7

CN X (Vagus)

Contributing Nuclei (4)

Type/Function

Answer 7

• Nucleus Ambiguous
  
  • Branchiomotor (LMNs)
  • Palatal, Pharyngeal and Laryngeal muscles (swallowing)
• Dorsal Motor Nucleus of Vagus
  
  • Visceromotor
  • Viscera of thorax and abdomen
• Solitary Nucleus
  
  • Visceroosensory
  • Taste from Epiglottis
  • Signals from Aortic body stretch and chemoreceptors
• Spinal Nucleus of V
  
  • Somatosensory
  • Pain and temp. from Larynx and esophagus

Question 8

CN XI (Accesory)

Contributing Nuclei (1)

Type/Function

Answer 8

• Accesory Nucleus
  
  • Branchiomotor (LMNs)
  • Sternocleidomastoid and trapezius muscles
• Runs down into spinal cord
  
  • Ventral horn-ish
  • C1-C5/6

Question 9

CN XII (Hypoglossal)

Contributing Nuclei (1)

Type/Function?

Answer 9

• Hypoglossal Nucleus
  
  • Somatomotor (LMNs)
  • Muscles of Tongue