Cranial Nerves Flashcards
How many pairs of cranial nerves are there
12
Where do cranial nerves innervate
The periphery of the brain
Where are cranial nerves located
Ventrolateral surface of brain
How are the cranial nerves numbered
Beginning at the anterior aspect of the brain
What’s the name for CN I?
Olfactory
What is the function of CN 1 and what type of nerve is it
Olafactory
Sense of smell
Sensory nerve
What is the name for CN II
Optic nerve
What is the function and type of nerve of CN II
Optic nerve
Function: vision
Sensory nerve
What is the origin and destination of CN II
Origin: retina of eye
Destination: diencephalon,
via optic canal (sphenoid)
then to occipital lobe
Which three nerves contribute to eye movement and what are those movements
CN III - oculomotor
CN IV - trochlear - superior oblique 💪🏽
CN VI - abducens - lateral rectus 💪🏽
What is the name of CN III
Oculomotor nerve
What is the function of CN III
Oculomotor
controls extra-ocular eye muscles
What motor functions of the eye does CN III control
Superior, rectus, medial rectus,
Inferior oblique
Lens
pupil
What is the origin of CN III
Mesencephalon
What is the destination of CN III
Extra ocular eye muscles
• Superior, inferior, & medial rectus
• Inferior oblique
• Levator palpebrae superioris
What is the foramen of CN III
Superior orbital fissure
What is the name of CN V
Trigeminal Nerve
What type of nerve is CN V
sensory & motor
What are the destinations of CN V and what do they impact
Trigeminal Nerve
Ophthalmic: sensations from forehead, eyelids, nose
Maxillary: sensations from lower eyelid, upper lip, cheek
Mandibular: controls mastication
What is the name for CN VII
Facial Nerve
What type of nerve is CN VII
Sensory and motor
What are the origins for CN VII
Facial
Sensory: taste buds
Motor: pons
What are the sensory and motor functions for CN VII
Facial
Sensory:
sensations from the face
anterior 2/3 of tongue
Somatic Motor:
Controls muscles of face
Visceral motor: lacrimal glands, nasal mucous glands, submandibular/submaxillary salivary glands, middle ear
What is the name for CN VIII
Vestibulocochlear
What type of nerve and what is the function of VIII
Sensory nerve
Function:
balance: vestibular branch
hearing: cochlear branch
What is the origin and destination of CN VIII
Vestibulocochlear
Origin: receptors of vestibule &cochlea
Destination: pons
What is the name of CN IX
Glossopharyngeal
What type of nerve is CN IX
Glossopharyngeal
Sensory & Motor
What are the functions of CN IX
Sensory function: tongue pain, blood pressure, dissolved gasses
Motor function: involuntary muscles of swallowing
What are the origins of CN IX
Glossopharyngeal
Sensory: posterior 1/3 of the tongue, carotid sinus (blood pressure, dissolved gas)
Motor: salivary gland
What is the name of CN X
Vagus nerve
Is the CN X nerve sympathetic or parasympathetic?
Parasympathetic
What type of nerve is CN X
Vagus Nerve
Sensory & Motor
What are the sensory and motor functions of CN X
Vagus Nerve
Sensory: information FROM organs
Motor: sends information TO organs
What are the origins of CN X
Vagus Nerve
Sensory: from the visceral organs
(to autonomic centers of medulla oblongata)
Motor: medullary oblongata
What is the name of CN XI
Accessory Nerve
What type of nerve is CN XI?
Motor Nerve
What is the function of CN XI and what all does that function control
Accessory Nerve
Function: accessory swallowing 💪🏽
Controls:
Sternocleidomastoid,
Trapezius,
Palate,
Pharynx (voluntary muscles of swallow
Larynx
What are the origins of CN XI
Spinal Cord & Medulla Oblongata
What is the name of CN IV
Trochlear
What is the function of CN IV
Trochlear
Eye movement:
Superior oblique muscle
What type of nerve is CN IV?
Motor
What is the destination of CN IV
Trochlear:
Superior oblique muscle
What is the name of CN VI
Abducens Nerve
What is the function of CN VI
Abducens:
Lateral rectus eye muscle
(Moving eye outward)
What type of nerve is CN VI
Abducens:
Motor
How are tendon reflexes graded?
0
1+
2+
3+
4+
What does a tendon reflex of 0 indicate
0 = no response; always abnormal
What does a tendon reflex of 1+ indicate
1+ = slight but present response
May or may not be normal
What does a tendon reflex of 2+ indicate
Normal; a brisk response
What does a tendon reflex of 3+ indicate
3+ = Very brisk response
May or may not be normal
What does a tendon reflex of 4+ indicate
4+ = elicits a repeating reflex
Always abnormal
Define a Clonus in regard to how tendon reflexes are graded
Clonus: a tap eliciting a repeating reflex
Always abnormal
Where are the nerve roots for the biceps?
C5
C6
C = Cervical spine
Where is the nerve root for the Brachioradialis?
C 6
(Cervical spine 6)
Where are the nerve roots for the triceps?
C7
(C6-C7)
Where are the nerve roots for the patellar / quadriceps ?
L4
( L2 - L4 )
Where are the nerve roots for the Achilles?
S1
( S1, S2 )
What are the motor destinations for VII
Glossopharyngeal nerve
Visceral motor: parotid salivary gland
Somatic motor: pharyngeal muscles for swallowing
What are the motor destinations for CN X?
Visceral motor: respiratory, cardiovascular, and digestive organs