CRANIAL NERVES - LECTURE B

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CRANIAL NERVES - LECTURE B
NBIO 401 Friday, October 8, 2009
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Abducens nucleus
Abducens nerve
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Genu of the Facial nerve
Abducens nucleus
Facial nucleus
Facial nerve
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Solitary nucleus (outside)
Abducens nucleus
Superior salivatory nucleus

• Facial intermediate nerve
• part of facial nerve carrying
• Motor
• motor output from the
• superior salivatory nucleus
• to some salivary glands (GVE)
• Sensory
• 1) taste information from
• the anterior 2/3 of the tongue to
• solitary nucleus via the solitary
• tract (SVA)
• 2) touch information from a
• small patch of skin on the ear and
• behind the ear to spinal trigeminal
• nucleus (GSA)

Spinal trigeminal nucleus
Solitary tract (inside)
Facial intermediate nerve
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Superior cerebellar peduncle
Spinocerebellar fibers (on route to the
cerebellum)
Inferior cerebellar peduncle
Middle cerebellar peduncle
Superior cochlear nucleus
Vestibulocochlear Nerve VIII Cochlear
component (carries auditory signals from
the cochlea to the cochlear nucleus)
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Inferior vestibular nucleus
Vestibulocochlear Nerve VIII vestibular
component (carries vestibular signals from
the vestibular labyrinth to the vestibular
nuclei)
Medial vestibular nucleus
Inferior Cerebellar peduncle
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Superior Cochlear nucleus
Vestibulocochlear Nerve VIII
Vestibular nuclei
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Spinal trigeminal nucleus tract
Inferior cerebellar peduncle (spinocerebellar fibe
rs to cerebellum)
Hypoglossal Nucleus
Vestibular nuclei
Solitary tract nucleus
MLF
Cochlear Nucleus (auditory information)
Spinothalamic Tract
Medial lemniscus
Inferior olive nucleus
Pyramidal Tract
Abducens nerve (to eye muscle)
Pontine Gray matter (relay signals to cerebellum)
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Inferior salivatory nucleus
Solitary nucleus tract
Spinal trigeminal Nucleus
Nucleus Ambiguus (motoneurons for larynx
pharynx muscles)

• Glossopharyngeal nerve IX
• carries
• Motor
• signals to the pharynx
• from nucleus ambiguus
• motor output from the inferior
• salivatory nucleus to some salivary
• glands
• Sensory
• 1) taste information from posterior
• 1/3 of tongue to the solitary nucleus
• via the solitary tract.
• touch information from the posterior
• 1/3 of the tongue, pharynx, some skin
• around the ear, internal surface of ear drum
• to the spinal trigeminal tract
• Pressure signals from the carotid
• artery

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Dorsal motor nucleus of the Vagus
Solitary nucleus tract
Nucleus ambiguus
Spinal trigeminal nucleus

• Roots of the vagus nerve X carries
• Motor
• motor signals to larynx pharynx muscles from
  motoneurons in nucleus ambiguus.
• 2) parasympathetic output to the larynx
  pharynx to organs of the chest abdomen from
  the dorsal
• motor nucleus of the vagus
• Sensory
• touch signals from pharynx, external ear canal,
  external side of the ear drum, skin of the ear
• to the spinal trigeminal nucleus.
• 2) taste information from the epiglottus to
  the solitary nucleus
• 3) sensory signals from the larynx, trachea,
  esophagus, chest abdomen viscera, pressure
  chemoreceptors
• in the aorta to the caudal part of the solitary
  nucleus.

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Spinal accessory nucleus (motoneurons
for sternocleidomastoid trapezius muscles)
Spinal accessory nerve
Spinal accessory roots
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Gracile fasciculus
Gracile Nucleus
Cuneate fasciculus
Cuneate nucleus
Spinal trigeminal nucleus tract
Spinal Accessory Nucleus
MLF
Pyramidal Decussation
Spinothalamic Tract
Pyramidal tract
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Solitary nucleus tract
Dorsal motor nuclei of the vagus
Vestibular nuclei
External cuneate nucleus
Spinal trigeminal nucleus tract
Nucleus ambiguus
Hypoglossal nuclei (motoneuron for tongue muscles)
Inferior olive
Hypoglossal nerve
Pyramidal tract
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Spinal trigeminal nucleus tract
Vestibular nuclei
Hypoglossal Nucleus
Solitary tract nucleus
Lateral cuneate nucleus
DMX
IVth ventricle
Inferior olive
Pyramidal tract
Medial lemniscus
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Somatic Motor Nuclei
Oculomotor nucleus
Hypoglossal nucleus
Oculomotor nerve
Trochlear nerve
Hypoglossal nerve
Trochlear nucleus
Abducens nucleus
Abducens nerve
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Special visceral (Branchial) Motor Nuclei
Trigeminal motor nucleus
Trigeminal nerve
Facial motor nerve
Facial motor nucleus
Nucleus ambiguus axons bound for glossopharyngeal
vagus nerves
Nucleus ambiguus
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General Visceral Motor Nuclei
Dorsal motor nucleus of the vagus
Axons from the dorsal motor nucleus of the vagus
bound for the vagus nerve
Inferior salivatory nucleus
Superior salivatory nucleus
Axons from the superior salivatory nucleus bound
for the facial nerve
Axons from the inferior salivatory nucleus
bound for the glossopharyngeal nerve
Edinger-Westphal nucleus
Edinger-Westphal fibers bound for the oculomotor
nerve
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Visceral Sensory Nuclei

• Facial intermediate
• Nerve (taste from anterior
• 2/3 of tongue to solitary
• nucleus)

• Glossopharyngeal nerve
• (taste from posterior 1/3
• of tongue to solitary nucleus)

Vagus nerve (taste from epiglottus to rostral
solitary nucleus, signals from the trachea,
esophagus, chest, abdomen aorta to caudal part
of solitary nucleus)
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