03. Visual Tracts (Dennis) Flashcards
What would damage to the optic chiasm present as?
Bitemporal hemianopia.
What specific part of the inferior optic radiance is vulnerable to ischemic events?
What deficit would this cause?
Meyer’s loop
Upper visual field defects.
What is the pathway for pupillary constriction?
Light enters the eye and is passed to the lateral geniculate bodies.
The lateral geniculate bodies send the signal to the pretectal nuclei.
The pretectal nuclei send bilateral signals to both Edinger Westphal nuclei
From there fibers run with the occulomotor nerve to the ciliary ganglia.
The ciliary ganglia sends fibers forward as the short ciliary nerve into the eye to contract.
After the decussation in the optic chiasm, where do the fibers of the optic nerve synapse?
In the lateral geniculate nucleus.
Where do we find Meyer’s loop?
As a part of the tract of the inferior optic radiance.
In which layers do fibers from the nasal retinal field synapse in the lateral geniculate nucleus?
In the contralateral layers 1, 4, and 6.
Where do the fibers of the visual tract go after they synapse in the lateral geniculate nucleus?
Through the optic radiations to the primary visual cortex above and below the calcarine sulcus.
Which layers of the lateral geniculate nucleus are magnocellular?
Layers 1 and 2
What are the ten layers of the retina, in the order that light passes through them?
Inner limiting membrane
Nerve fiber layer
Ganglion cell layer
Inner plexiform layer
Inner nuclear layer
Outer plexiform layer
Outer nuclear layer
Outer limiting membrane
Rods and cones
Retinal pigmented epithelium
Lamina vitria
Choroid
Impotent Naked Grandfathers Ignore Insatiable Optimistic Onlookers. Old Rods Rebel, Lying Curled.
What Brodmann areas are associated with the primary visual cortex and the visual association cortex respectively?
Primary visual cortex is Brodmann 17
Visual association cortex is Bronmann 18 and 19.
Which layers of the lateral geniculate nucleus receive input from rods?
Layers 1 and 2
Where is the image of interest typically localized in the retina?
On the fovea centralis and the macula lutea.
How does the superior colliculus assist in vision?
Helps to direct eye movements.
What does “macular sparing” refer to?
An issue leaving the occipital pole alone, but damaging the other parts of the occipital lobe.
Which half of the visual field is conveyed on ipsilateral fibers?
The nasal part of the visual field
(The temporal part of the retinal field)
What are the histological layers of the cornea?
corneal epithelium-nonkeratinized stratified squamous
Bowman’s membranre-corneal epithelium
Corneal Stroma-unique orientation of cells and stroma, AVASCULAR
Descemet’s membrane-corneal endothelium, very thicc
Corneal endothelium-simple sqaumous epithelium facing anterior chamber
