Cranial Nerves Flashcards
What forms the sensory portion of the brain stem as it developed from the neural tube ?
The Alar plate, positioned posteriorly, will form the sensory portion of the brain stem
What will the motor portion of the brain stem develop from ?
The Basal plate, positioned anteriorly, will form the motor portion of the brain stem.
What separates the basal plate from the alar plate?
The sulcus limitans
CN-1
Olfactory: More of a tract than a nerve. It carries fibers from the olfactory bulb to the olfactory portion of the cerebral cortex.
CN-2
Optic Nerve: Carries visual information from the retina to the optic chasm
CN-3
Occulomotor:
1. GSE Nucleus- tegmentum of the rostral midbrain at the level of the superior colliculus. Responsible for all of the eye movements. Except for SO4 LR6
- GVE nucleus Edinger- Westphal Nucleus which is posterior to the occulomotor nucleus. These fibers are involved in the pupillary light reflex and accommodation
CN-4
Trochlear, located in the tegmentum of the mid brain. GSE innervate the contralateral superior oblique. The fibers cross over before exiting caudal to the inferior colliculus.
CN-5
Trigeminal- Principle GSA to the head. Provides SVE or BE to the muscles of mastication.
mesencephalic nucleus
GSA CN5- Proprioception from the muscles of mastication
Chief nucleus
Discriminative touch and vibration from the head.
Spinal Nucleus
GSA, pain and temperature from the head.
Motor Nucleus
SVE / BE –> Motor to the muscles of mastication
CN-6
Abducen Nucleus GSE, motor to the lateral rectus
Where does the facial nerve emerge from the brain stem ?
Pontomedullary Junction
Facial Nucleus
CN-7 –> SVE / BE –> Motor to the muscles of facial expression.
Chief nucleus of CN 5- Hint, not the CN-5 function
GSA –> Sensory from the external acoustic meatus and skin posterior to the ear.
Superior Salivary Nucleus
GVE –> Parasympathetic motor to the lacrimal, sublingual, and submandibular glands.
Nucleus Solitarius
GVA- Chemoreceptors and barioreceptors in the carotid body, visceral afferent information from the young and pharynx
SVA- Taste from the anterior 2/3 of the tongue
What two nuclei does the vestibulococlear nerve synapse in ?
Vestibular nuclear complex and cochlear nuclear complex
Vestibular nuclear complex
CN-8 SSA –> Balance
Cochlear Nuclear Complex
CN-8 SSA –> Hearing
What are the two divisions of the facial nerve ?
- The facial nerve proper- Motor control to the muscles of facial expression ( SVE & BE )
- Nervus Intermedius
CN-8
Vestibulocochlear
What types of fibers does the vestibulocochlear nerve carry ?
Vestibular fibers for balance and Cochlear fibers for hearing.
