Cranial Nerves
How many cranial nerve pairs are there?
12
The thalamus emerges from what secondary vesicle?
diencephalon
What are the three layers of the human eye?
Sclera, choroid, and uvea
What is a map that depicts each body part's cortical representation for voluntary movement?
Motor homunculus
A lesion to the left optic nerve will result in what?
Left anopsia or anopsia O.S. (ocular sinister)
What are the three categories?
Special sensory, somatic motor, branchiomeric
What are the four components of the thalamus?
Hypothalamus, epithalamus, subthalamus, thalamus
What retina receptors are specialized to receive colors and acuity?
Cones
What muscle fiber and motor unit contracts strongly for a moderate amount of time?
White (type IIa) and fast-twitch fatigue-resistant
A lesion to the LGN will result in this?
Homonymous hemianopsia
Bell's Palsy is associated with a lesion at which cranial nerve?
Cranial nerve VII or facial
What area of the thalamus relays auditory information?
Medial geniculate nucleus (MGN)
What visual fields does each eye have?
What is the primary function of the corticobulbar tract?
voluntary movement of the head and face
A lesion to the parietal radiations would result in this?
Inferior homonymous quadrantanopsia
Lesions to which cranial nerves result in dysphagia and/or dysarthria?
Cranial nerve X (vagus) and cranial nerve XII (hypoglossal)
What condition consists of thalamic pain, hemianesthesia, and sensory ataxia?
Thalamic syndrome
Which stream and/or pathway is associated with color and form?
ventral stream/parvocellular pathway
Why is cranial nerve VII an exception to bilateral innervation in the corticobulbar tract?
Contralaterally innervate the CN VII nucleus for lower face muscles
A 60-year-old man c/o transient episodes consisting of light-headedness, vision disturbances, nausea, and unsteadiness. A CT revealed a lesion in the inferior aspect of the right temporal lobe. What visual disorder did the patient most likely experience?
Inability to see objects in the left superior quadrants of both eyes
What are the functional components of cranial nerves?
Where is the location of the internal capsule in regard to the thalamus?
Lateral to the thalamus
What are the extraocular muscles?
medial rectus, superior rectus, inferior rectus, inferior oblique, superior oblique, lateral rectus
Unilateral corticobulbar damage (ex. a right brain stroke) will result in what?
Contralateral weakness of lower facial muscles, but spare upper facial muscles
A 55 y.o. woman with a long-standing h/o menstrual irregularity consulted with her ophthalmologist, indicating she was experiencing visual disturbances. A CT revealed a pituitary tumor impinging on the optic chiasm. What is the most likely visual deficit?
Bitemporal hemianopsia