Motor cranial nerves Flashcards
The structures that initiate lateral gaze are:
A. Superior colliculus and medial geniculate body
B. Frontal eye fields and parapontine reticular formation
C. Abducens nucleus and oculomotor nerve complex
D. Rostral interstitial nucleus of Cajal
B
On looking to the left side (L) to copy a friend’s scantron, your classmate Derpina develops diplopia. She has no problem copying answers off a friend seated to her right (R). She has dysconjugate gaze due to:
A. Disconnected medial longitudinal fasciculus between L CN VI and R CN III
B. Non-functioning frontal eye field on the R side
C. A cerebellar lesion on the L side
D. Non-functioning parapontine reticular formation on the L side
A
The particular muscle to zero in while examining a patient with facial weakness to determine whether lesion is either upper or lower motor neuron is:
A. Frontalis
B. Nasalis
C. Buccinator
D. Orbicularis oris
A
One of the following muscles innervated by the CN V can be tested in the neurologic exam
A. Frontalis
B. Masseter
C. Orbicularis oris
D. Mylohyoid
B
In assessing the integrity of the motor component of CN V, the ball of the palm is placed on:
A. The maxilla
B. The mandible
C. The glabella
D. The chin
B
In assessing the integrity of the spinal accessory nerve, the ball of the palm is placed on:
A. The maxilla
B. The mandible
C. The glabella
D. The chin
A
A peripheral facial nerve weakness can be differentiated from a central facial nerve palsy by asking the patient to:
A. Wrinkle the forehead
B. Smile
C. Close the eyes tight
D. Pull the corners of the mouth downward forcefully
A
A lesion of the right CN XII or the supranuclear corticobulbar fibers on the right will be manifested by this finding on tongue protrusion
A. Remains in midline
B. Deviates to right on tongue protrusion
C. Deviates to left on tongue protrusion
D. Poor gag reflex
B
The cranial nerve that innervates the smallest skeletal muscle in the body
A. Oculomotor nerve
B. Trigeminal nerve
C. Abducens nerve
D. Facial nerve
D
Which structure has nothing to do with vertical gaze?
A. Oculomotor nerve
B. Trochlear nerve
C. Abducens nerve
D. Medial longitudinal fasciculus
C
The corneal reflex may be absent unilaterally due to a cervical cord lesion because:
A. Fibers descend from the principal nucleus to meet the gracile and cuneate tracts
B. Fibers descend as the spinal nucleus and tract to the 2nd cord segment
C. Fibers decussate at the level of the pons to join the medial lemniscus
D. Fibers descend and hitchhike on ascending fibers from CN XI
B
What do you call the lower motor neurons in the brainstem which the corticobulbar fibers from the motor cortex synapse with?
A. Cranial nerve motor nuclei B. Anterior horn cells C. Gamma motor neurons D. Interneurons E. Intrafusal cells
A
The upper motor neurons from the motor cortex do not synapse with which of the following cranial nerve nuclei?
A. Trigeminal nerve B. Oculomotor nerve C. Vestibulocochlear nerve D. Hypoglossal nerve E. Glossopharyngeal nerve
C
How does a left peripheral facial palsy manifest?
A. Paralysis of the left forehead
B. Paralysis of the right lower half of the face
C. Paralysis of the left lower half of the face
D. Paralysis of the entire right half of the face
E. Paralysis of the entire left half of the face
E
A monocular field defect suggests:
A. Lesion in the optic nerve
B. Lesion in the optic chiasm
C. Lesion in the optic radiation
D. Lesion at the occipital lobe
A