Visual Pathway Flashcards
(57 cards)
Three neurons of retina
- photoreceptors
- bipolar cells
- ganglions
What forms the axons of ganglion cells?
- optic nerve, chiasma and tract
Also known as geniculocalcacrine tract or geniculostriate
Optic radiation
Area 17
Striate or calcacrine cortex
What forms the axons from LGB?
Optic radiation
Two divisions of retina
Nasal and temporal
Two zones of visual field
- binocular
- monocular
Series of gray mater, flattened nucleus so it is striated or laminated
Lateral geniculate body
Lesion on the entire length of the optic radiation will result blindness on the left is called?
Left homonymous hemaniopsia
Lesion on the superior part of the optic radiation will produce?
Quadrantinopsia
Rounds the temporal horn of the lateral ventricle which refers to the lower fiber of the optic radiation
Meyer’s loop
Lesion in meyer’s loop
Right upper quadrantonopsia
Where does the fibers from upper and lower quadrants of visual field and the lower and upper quadrants of retina terminated?
Upper visual and lower retina- Lateral part LGB
Lower visual and upper retina medial part of LGB
Location of area 17
Upper banks of calcacrine sulcus
The central portion of the retina is the area of most acute vision is called?
Macula lutea
An area of pure cones in the macula lutea
Fovea centralis
Lesion in the dual blood supply
Macular sparring
Blood supply of visual cortex
- posterior cerebral artery
- middle cerebral artery
The tip of occipital lobe where the macular or central homonymous hemifields are represented is supplied by branches of the middle and posterior cerebral arteries
Watershed area
Lesion of the optic nerve
Blindness or anopsia
Lesion on the optic chiasm
Bitemporal or binasal hemianopsia
Termination pathway of optic tract
- LGN
- Suprachiasmatic nucleus of the hypothalamus
- pretectal nucleus
- superior colliculus
Most of the fibers of optic tract terminated here
LGN
Vision have major role in endocrine and autonomic function
Suprachiasmatic nucleus of the hypothalamus
