Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
28 Cards in this Set
- Front
- Back
|
Retinal projections: hypothalamus
|
Circadian rhythms
|
|
|
Retinal projections: pretectal
|
pupil size
|
|
|
Retinal projections: superior colliculus
|
eye movements and head orientation in response to stimuli
|
|
|
Retinal projections: lateral geniculate nucleus
|
primary visual cortex
|
|
|
Name of retinal axons posterior to chiasm
|
Optic tracts
|
|
|
Which side of the head will be affected if damage occurs posterior to chiasm?
|
Deficits in visual fields of both eyes
|
|
|
Where is the one synapse of the optic tract before the visual cortex?
|
Lateral geniculate nucleus
|
|
|
Names for the optic tract from the LGN to the visual cortex
|
Retrolenticular limb of IC, geniculocalcarine fibers, optic radiations
|
|
|
What compartment are all visual fibers in?
|
Supratentorial
|
|
|
Significance of Meyer's loop
|
Optic radiations that go forward into the temporal lobe before terminating in the visual cortex.
|
|
|
Where in the primary visual cortex do lateral optic radiations terminate? Medial?
|
Lingual gyrus. Cuneus gyrus.
|
|
|
How is visual field represented on retina?
|
Inverted and reversed
|
|
|
Which fibers cross at optic chiasm?
|
Nasal retinal fibers. Temporal retinal do not
|
|
|
Where do retinal axons terminate in LGN?
|
Lower retina = lateral LGN, upper retina = medial LGN
|
|
|
What fibers terminate in the lingual gyrus?
|
The laternal LGN fibers
|
|
|
What visual field goes to the R LGN?
|
The entire left half (ipsilateral from the temporal, contralateral from the nasal)
|
|
|
What visual field goes to the L LGN?
|
The entire R half (again, temporal is ipsilateral while the nasal is contralateral)
|
|
|
What happens if the L LGN is destroyed?
|
The entire R half of the visual field in BOTH EYES will be eliminated.
|
|
|
What part of the brain recieves the left visual field? The right?
|
R visual cortex, L visual cortex
|
|
|
What is the fate of the medial LGN fibers?
|
They loop into the parietal lobe (remember the lateral go to the lingual gyrus) before terminating in the cuneus gyrus.
|
|
|
How do I knock out all lower visual field input? Upper?
|
Whack the parietal lobe. Whack the temporal lobe (Meyer's loop)
|
|
|
Part of the retina with highest visual acuity? Highest color acuity?
|
Macula lutea. Fovea Centralis.
|
|
|
Where is the cortical representation of the macula lutea?
|
Large caudal portion of occipital lobe. (More somatosensory distribution -- more cortex for more sensitive vision is a recurring theme here)
|
|
|
Deficit in the visual field, term
|
Scotoma
|
|
|
No vision in right eye
|
Damage to the optic nerve
|
|
|
No vision in left half of left eye and right half of right eye - i.e. bilateral hemianopsia (hetereonymous).
|
Transection of the optic chiasm (knockout nasal input while temporal input is just fine). Can be caused by pituitary tumors
|
|
|
No vision in left visual field of both eyes - homonymous hemianopsia
|
Damage to R optic tract on their happy way to the R LGN
OR Lesion to all optic radiations to the R visual cortex |
|
|
No vision in UPPER left quadrant of both eyes
|
Damage to R optic radiations (most likely those in Meyer's loop -- the medial optic radiations typically represent lower quadrant
of the visual fields, or upper quandrant of the retina) |
