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Neuroscience > Visual System > Flashcards

Flashcards in Visual System Deck (49):
1

uvea

the apparatus of ciliary body and iris

2

retinal pigment epithelium fxn? layer?

instrumental in the health of the retina. without it the retina dies (i.e. retinal detachment)
layer 1

3

optic disk

where gangion cell axons collect to form the optic nerve; blind spot

4

macula lutea

- contains the FOVEA,
- most ACUTE vision.
- it is YELLOW

5

where does the optic nerve come from

developmentally the optic cup comes from the diencephalon

6

review: where does the lens come from?

the ectoderm.

7

whats layer 2

Rods and cones

8

rods and cones project to?

horizontal and bipolar cell

9

what do horizontal cells connect to

- other rods/cones.

10

what do bipolar cells connect to

rods/ cones ==> amacrine cell and gangion cell

11

amacrine cells connect to

bipolar cells and ganglion cells

12

where are the nuclei of rods and cones

in the outer nuclear layer (layer 4)

13

where do the synapses between bipolar cell and rods/cones

outer plexiform layer (layer 5)

14

where are bipolar cell bodies

inner nuclear layer (layer 6)

15

where bipolar cells synapse with ganglion cell

inner plexiform layer (layer 7)

16

where the banblion cell body is

ganglion cell layer (layer 8)

17

optic disk is ALWAYS ___ to fovea

medial

18

are there retinal layers in fovea?

not really. there are only cones here, and the cones have a 1:1 relationship with bipolar cells.... the info basically goes directly to the photoreceptor layer of the eye. theres a lot LESS convergence

19

scotopic vision is

low light vision

20

photopic vision is

best acuity becuase the cones are taking over, and rod saturation is present

21

what portion of the retinal information goes over to the right lateral geniculate nucleus

right lateral geniculate nucleus gets info from the temporal half of the R retina AND the nasal portion of the L retina

22

optic tract gets blood from?
lesion is called?

anterior choroidal artery. lesion is homonymous defect

23

4 arteries of optic radiations

PCA deep branches, anterior choroidal, MCA inferior division, PCA

24

first two layers of lateral geniculate nucleus

magnocellular layrs, receive input from retinal ganglion from M cells; LARGE receptive fields that are FAST conducting, info relating to MOTION

25

last four layers of lateral geniculate layers

parvocellular layers get input from retinal ganglion p cells and have SMALL receptive fields and COLOR info (cones)

26

what layers of lateral geniculate layers are for CONTRALATERAL eye

contralateral=1,4,6

27

each point in visual space is mapped....

6 times in the LGN

28

line of gennari

axons that form a line in layer 4 of the cortex... primarily in layer 4C
THIS IS ONLY IN BRODMAN AREA 17

29

layer 4C alpha gets info from

M cells (magnocellular)

30

layer 4C beta gets info from

P cells (parvocellular)
Crunchy Peanut Butter ==>4Cbeta=Pcells

31

striate cortex

the special name for the primary visual cortex

32

akinetopsia

a lesion to the WHERE stream; its the inferior temporal part; related to color and form. problem recognizing faces, color

33

which brodman areas have V3, V4, V5

18 and 19

34

functional columns of the striate cortex

they all respond to a BAR of light with the same angle. this is called orientation columns; they are also organized by blobs and ocular dominance columns (R vs L)

35

scotoma

little blind SPOTS that you can get from diabetes. you probably won't even know that you have them unless you get a visual field test done

36

monocular visual loss

total transection of the optic nerve; total loss of the visual field in one eye

37

bitemporal hemianopia

loss of the nasal portions of bilateral retinas; you lose the temporal visual field in both eyes; this is a lesion of the optic chiasm

38

contralateral homonymous hemianopia

loss of the same half of the visual field in each eye; loss of optic tract or a total transection of the optic radiation

39

contralateral superior quadrantopia

lesion of meyer's loop; loss of upper quarter of visual field in both eyes (same side in both eyes); pie in the sky

40

contralateral inferior quadrantopia

pie on the floor; loss of superior portion of the optic radiation; loss of lower quarter of visual field in both eyes, (same side in both eyes)

41

prosopagnosia

inability to recognize FACES; especially a lesion to the right side; inferior occipital gyrus, middle fusiform gyrus; PCA

42

capgras syndrome

don't have the EMOTIONALtie to the visual tie; problem connecting to the AMYGDALA; it looks like your parent, it looks like someone you know, but you deny that its your parent because you just don't have that connection

43

achromaatopsia

damage to area V4 (area 19) partial or complete loss of color vision. the WHAT stream

44

left hemineglect lesion

right parietal region

45

balint syndrome

usually a lesion to the left PARIETAL lobe; optic ataxia ; gaze apraxia ; simultanagnosia

46

simultagnosia

problem paying attention to MULTIPLE things in their visual field

47

gaze apraxia

deficit in directing gaze

48

number- color synestheesia

when they see a NUMBER, its a COLOR; lesion with the FUSIFORM area of the left brain

49

blind sight syndrome

new pathway is damaged, but the old pathway is intact so they can orient objects and track with eyes and head. they have a "sixth sense"