M13: Cranial Nerve Names, Functions, & How to Test Them Flashcards
Roman Numerals Review
I = 1
II = 2
III = 3
IV = 4
V = 5
VI = 6
VII = 7
VIII = 8
IX = 9
X = 10
XI = 11
XII = 12
What is the name and general function of cranial nerve I (CN I)?
Is it sensory, motor, or both (i.e. mixed)?
Olfactory Nerve
Sensation of Smell (Sensory Only)
What is the name and general function of CN II?
Is it sensory, motor, or both (i.e. mixed)?
Optic Nerve
Vision (Sensory Only)
What is the name and general function of CN III?
Is it sensory, motor, or both (i.e. mixed)?
Oculomotor Nerve
Motor control of eye (Motor Only)
What is the name and general function of CN IV?
Is it sensory, motor, or both (i.e. mixed)?
Trochlear Nerve
Motor Control of Eye (Motor Only)
Specifically it moves the eye up and down
What is the name and general function of CN V?
Is it sensory, motor, or both (i.e. mixed)?
Trigeminal Nerve
sensory and motor control of facial muscles and receptors
(Mixed sensory and motor)
What is the name and general function of CN VI?
Is it sensory, motor, or both (i.e. mixed)?
- Abducens Nerve
- motor eye movement; abducts eye (i.e. lateral gaze)
- motor only
What is the name and general function of CN VII?
Is it sensory, motor, or both (mixed)?
Facial Nerve
Mixed, both Sensory and Motor Function to the Facial Region
What is the name and general function of CN VIII?
Vestibulocochlear Nerve
Special sensory nerve for balance, equilibrium and hearing
(Sensory only)
What is the name and general function of CN IX?
Glossopharyngeal Nerve
Sensory and Motor Functions to Head and Neck
(Mixed)
What is the name and general function of CN X?
Vagus Nerve
Mixed motor and sensory widely distributed throughout the thorax and abdomen. (Parasympathetic)
Note: the majority of the nerve fibers are sensory 80-90% of the nerve fibers in the vagus nerve are afferent (sensory) nerves communicating the state of the viscera to the brain
What is the name and general function of CN XI?
Accessory Nerve
Motor Control of the Neck and Upper Back
(Motor Only)
What is the name and general function of CN XII?
Hypoglossal Nerve
Tongue Movement (Motor Only)
Which cranial nerves contain only afferent (sensory fibers)?
- Olfactory Nerve I (Sense of smell)
- Optic Nerve II (Vision)
- Vestibulocochlear Nerve VIII (balance, equilibrium, hearing)
Which cranial nerves contain only efferent (motor) fibers?
- III Oculomotor Nerve
- IV Trochlear Nerve
- VI Abducens Nerve
- XI Accessory Nerve
- XII Hypoglossal Nerve
Which cranial nerves contain both sensory and motor fibers (mixed)?
- V Trigeminal Nerve
- VII Facial Nerve
- IX Glossopharyngeal Nerve
- X Vagus Nerve
How do we test cranial nerve I?
Smell test
e.g. using an alcohol prep pad
cranial nerve I = olfactory nerve
How do we test for the optic nerve (II)?
Test Vision
- e.g. ask them to read something
- e.g. ask them if there are any vision changes like blurry vision, double vision, eye floaters/black spots, etc.
How do we test the oculomotor nerve (III)?
PERRL Test
- Are both pupils equal in size and round?
- Are they reactive to light?
How do we test abducens nerve (VI)?
Test Motor Eye Movement Lateral Gaze (Left to Right, Right to Left)
How do we test the trigeminal nerve (V)?
Trigminal does both sensory and motor control of facial muscles and receptors, so
- smile and frown
- touch both sides of face
How do we test the trochlear nerve (IV)?
Test motor eye movement up and down gaze
Bonus: the torchlear nerve innnervates just one muscle of the eye (the trochlea) named so due it’s pulley-like action.
What does PERRL stand for?
PERRL
- P (Pupils)
- E (Equal)
- R (Round)
- R (Reactive to)
- L (Light
