Cranial Nerves Flashcards
what is the function and where can it get lesioned if applicable.
CN1
Olfactory nerve
relays olfaction (sense of smell) into the CNS
Lesion: ipsilateral anosmia
what is the function and where can it get lesioned if applicable.
CN2
Optic Nerve
relay visual info into the CNS
Lesion on optic nerve: ipsilateral loss of vision
what is the function and where can it get lesioned if applicable.
CN3
Oculomotor nerve
LMN innervating 4 of 6 eye muscles & upper eyelid muscle
lesion on edinger-westphal nucleus: dilated pupil on ipsilateral side and loss of accomidation on ipsilateral side
lesion on oculomotor nucleus or nerve: ipsilateral flaccid paralysis of 4 or 6 muscles and superior eyelid muscle
ipsilateral eye will deviate laterally (ipsilateral lateral strabismus)
Ptosis=drooping superior eyelid on ipsilateral side
what is the function and where can it get lesioned if applicable.
CN4
Trochlear nerve
LMN innervates superior oblique eye muscle (eye movement needed for walking down flight of stairs)
Lesion to trochlear nucleus: ipsilateral flaccid paralysis of the superior oblique eye muscle.
ipsilateral eye will deviate up and out
what is the function and where can it get lesioned if applicable.
CN5
Trigeminal Nerve
Relays somatosensation from the face
LMN to muscles of mastication
Lesion on
principle sensory mucleus: ipsilateral loss of discriminative touch and vibration of the muscles
trigeminal motor nucleus: ipsilateral flaccid paralysis of the muscles of mastication
mesencephalic nucleus and tract: ipsilateral loss of proprioception from the face
spinal trigeminal nucleus and tract= ipsilateral loss of pain and temperature from the face
what is the function and where can it get lesioned if applicable.
CN6
Abducens nerve
LMN that innervates ipsilateral rectus muscle of the eye
Lesion to abducens nucleus: ipsilateral flaccid paralysis of the lateral rectus eye muscle ipsilateral eye will deviate medially (ipsilateral medial strabismus)
what is the function and where can it get lesioned if applicable.
CN 7
Facial Nerve
LMN innervation to muscles of facial expression
Relays taste sensation from anterior 2.3 of ipsilateral tounge
Parasympathetic preganglionic to ipsilateral glands of the face.
Lesion to facial motor nucleus or nerve: ipsilateral flaccid paralysis of the muscles of facial expression
what is the function and where can it get lesioned if applicable.
CN 8
Vestibulocochlear nerve
relays vestibular and auditory sense to the brain
what is the function and where can it get lesioned if applicable.
CN 9
Glossopharyngeal nerve
relays visceral sensation from the carotid body and sinus
relays taste sensation from the posterior 1/3 of tounge
LMN that innervates the stylopharyngeus muscle
PNS preganglionic to the parotid gland
relays sensation from posterior tounge, inner tympanic membrane and skin of ear
what is the function and where can it get lesioned if applicable.
CN 10
Vagus Nerve
Relays visceral sensation from visceral organs of thoracic and abdominal cavities
LMN that innervates the muscles of the laryn and pharynx
PNS preganglionic to the visceral organs of thoracic and abdominal cavities
lesion on nucleus ambiguous: ipsilateral dysarthia and dysphagia
what is the function and where can it get lesioned if applicable.
CN 11
Spinal Accessory Nerve
LMN whose cell body resides in cervical anterior horn
Nerve leaves the SC and goes into the cranium via the foramen magnum and leaves via jugular foramen
Innervates the ipsilateral trapezius and sternocleidomastoid muscle
Lesion on spinal accessory nerve: ipsilateral flaccid paralysis of the sternocleidomastoid and trapezius muscle
what is the function and where can it get lesioned if applicable.
CN 12
Hypoglossal nerve
LMN that innervate the ipsilateral tounge muscles
Lesion on hypoglossal nucleus or nerve: ipsilateral flaccid paralysis/atrophy of the tounge
tounge will deviate towards the ipsilateral side when protruded
