Lecture 20: Visual Tracts Flashcards
An image focused on the retina will be centered at what structures?
Fovea centralis
Macula lutea
What structure is found at the blind spot of the retina?
Optic disc: located medial to the macula
What structure does the optic tract terminate in?
Lateral Geniculate Nucleus
What fibers of the optic radiations are received by the superior bank of the calcarine sulcus?
What lobe?
Fibers from lower quadrant of contralateral hemifields
Cuneus
What fibers from the optic radiations target the inferior bank of the calcarine sulcus?
What part of the occipital lobe?
Fibers from upper quadrant of contralateral hemifields
Lingual gyrus
What fibers form the Meyer loop?
Fibers from upper quadrant of contralateral hemifields
Pass into temporal lobe to form u-turn
Fibers conveying information from the ____ and ___ originate from central regions of the LGN and pass to caudal portions of the visual cortex.
Macula
Fovea
What visual field deficit can be produced if there is a lesion to the temporal lobe?
What visual structure has been damaged?
Superior visual field deficit: damage to Meyer’s loop
Where does the retinal input to the superior colliculus come from?
Select fibers from optic tract that bypass the LGN
What is the function of the superior colliculus?
Spatailly directs head movements and visual reflexes
What is a heteronymous visual field lesion?
Two eyes have non-overlapping field losses
What kinds of visual field deficits are produced when there is damage anterior to the optic chiasm?
Deficit only in ipsilateral eye
What kind of visual field deficits are produced when there is damage at the optic chiasm?
Heteronymous deficits
Damage behind the optic chiasm causes what kind of visual field deficits?
Homonymous deficits
The closer a lesion is to ___, the more congruous it is likely to be.
Visual cortex