vision 2

Question 1

what retinal information is in the optic nerve

Answer 1

-the retinal nerve contains information from the ipsilateral temporal retina and the ipsilateral nasal retina

Question 2

what visual field information is in the optic nerve

Answer 2

visual field information about the contralateral nasal visual field and the ipsilateral temporal visual field is in the optic nerve

Question 3

what happens if you cut an optic nerve

Answer 3

you lose vision in the contralateral nasal visual field and ipsilateral temporal visual field
-the other eye should be able to restore the nasal visual field because that region is binocular

Question 4

what nerves intersect at the chiasm

Answer 4

the right and left nasal retinas which convey information about their ipsilateral temporal visual fields

Question 5

what is the benefit of center surround antagonism

Answer 5

it provides enhancement and edge detection

Question 6

how do horizontal cells influence photoreceptor cells

Answer 6

horizontal cells hyperpolarize photoreceptor cells

Question 7

what is the mechanism for depolarization of ON center bipolar cells

Answer 7

-metabotropic channels are activated by glutamate on ON center bipolar cells. This is accomplished by a G protein channel and secondary messengers (unknown exactly)
-TRP1 channels remain closed

Question 8

what are the characteristics of magnocellular cells

Answer 8

10% total RGC cells, large receptive field, expansive dendritic field, respond to large moving objects, rapid conduction,

Question 9

what are the characteristics of parvocellular cells

Answer 9

80% retinal ganglion cells, smaller receptive field, small dendritic field, concentrated in fovea, slower conduction

Question 10

what are the characteristics of koniocellular cells

Answer 10

1% of RGCs, large dendritic field

Question 11

where do blue On/yellow Off cells project to

Answer 11

the parvocellular and koniocellular pathways

Question 12

parvocellular pathway

Answer 12

parvocellular cells (P cells) project from the retina to the ventral geniculate nuclei (layers 3-6) to the striate cortex (layer 4c beta) to the interblob and blob regions to other cortical areas

Question 13

magnocellular pathway

Answer 13

magnocellular cells (M cells) project from the retina to the ventral geniculate nuclei (layers 1 and 2) to the striate cortex (layer 4c alpha) to layer 4b and to the blob (collateral), then to extrastriate cortical regions

Question 14

koniocellular pathway

Answer 14

nonM/nonP ganglion cells to the extra laminal area in the VGN to the blob to the extrastriate areas

Question 15

what kinds of cells are in the interblob

Answer 15

complex and simple cells; binocular, orientation selective, direction selective

Question 16

what kinds of cells are in the blob

Answer 16

monocular, wavelength sensitive, circular receptive field

Question 17

what is the difference between simple and complex cells

Answer 17

idk watch lecture again if u get this and dont know still
-simple cells will either fire if activated or not fire if not while complex cells will fire for different conditions??

Question 18

are visual signals between the eyes segregated up in the striate cortex

Answer 18

yes

Question 19

fun fact: most v1 neurons outside of layer 4c are orientation selective

Answer 19

did you know that?

Question 20

where does mixing of the pathways for both eyes first occur

Answer 20

in v1 of the striate cortex

Question 21

location of intracortical pyramidal cells which make horizontal connections

Answer 21

layer 3

Question 22

are most intracortical connections horizontal or radial

Answer 22

radial

Question 23

where do stellate neurons project to

Answer 23

4b alpha and 3 beta. 2 and 3 receive binocular input

Question 24

what is the difference between stellate and pyramidal cells

Answer 24

LOOK AT LECTURE if u dont know this yet

Question 25

which pyrimidal cells project to cortical areas outside of the striate cortex

Answer 25

layers 2, 3, and 4b

Question 26

which pyrimidal cells project to the superior colliculus and pons

Answer 26

layer 5

Question 27

which pyrimidal cells project back to the LGN

Answer 27

layer 6

Question 28

what retinal and visual information does meyer’s loop represent

Answer 28

inferior retinal quadrant/superior visual field

Question 29

what happens if you cut right meyer’s loop

Answer 29

you lose the right eye’s nasal visual field and the left eye’s ipsilateral temporal visual field

the left eye can still see the right eye’s visual field, so you end with 150 degree vision only missing the left eye’s temporal visual field

Question 30

what are ipRGCs and what is their significance

Answer 30

these are inner plexiform retinal ganglion cells which control circaidian photoentrainment and control the pupillary light reflex

Question 31

what is the significance of the macula

Answer 31

the macula is an area behind the retina and the fovea sits inside, very important for vision

Question 32

where is the striate cortex located

Answer 32

the occipital lobe

Question 33

what is the pupillary light reflex pathway

Answer 33

axons from the retina/optic nerve synapse with edinger westphal nucleus interneuron then the pretectum then the ciliary ganglion then innervate the pupilliary constrictor muscle

Question 34

what is the difference between stellate and pyrimidal cells and their projections

Question 35

ocular dominance columns

Answer 35

Regions of neurons in the striate cortex that synapse with axons carrying transduced
signals from either the left or right eye

Question 36

describe the receptor field of simple cells

Answer 36

binocular, orientation selective, elongated on-off region,

Question 37

describe the receptor field of complex cells

Answer 37

binocular, orientation selective, do not fire for certain orientations, no antagonistic flanks/distinct on off regions