Vision

Question 1

Cornea

Answer 1

curved transparent external surface of eye, causes light to bend, no receptive field

Question 2

Pupil

Answer 2

the Opening allows light to enter the eye, no receptive field

Question 3

Iris-circular muscle

Answer 3

controls pupil size, no receptive field

Question 4

lens

Answer 4

focuses the light of the retina, no receptive field

Question 5

Ciliary muscles

Answer 5

control lens shape

Question 6

Accomadation

Answer 6

process of lens changing to focus on different objects

Question 7

Extraocular muscles

Answer 7

control eye movement

Question 8

Retina

Answer 8

layers of cells at the back of the eye,
rods and cones(Spot of light)
bipolar cells(Concentric RF)
ganglion cells(Concentric RF)
axons of ganglion cells form the optic nerve

Question 9

Rods and Cones(photoreceptors)

Answer 9

transduce light, spot of light

Question 10

Two functional systems of Retina

Answer 10

Scotopic system, Photopic system

Question 11

Scotopic System

Answer 11

functions in dim light, one type of receptor(rods)

Question 12

Photopic system

Answer 12

functions in brighter light, three types of (cone) receptors

Question 13

photopigment(captures light) in rods

Answer 13

rhodopsin

Question 14

rhodopsin

Answer 14

composed of retinal and opsin

Question 15

Photoreceptors Hyperpolarization

Answer 15

1. light activates rhodopsin
2. retinal dissociates from opsin
3. opsin binds G protein
4. G protein transforms 2nd messenger
5. blocking Na+ channels causing hyperpolarization(and less glutamate release)

Question 16

Cones Function

Answer 16

similar to rods but have three different types of opsin

Question 17

on center bipolar cells

Answer 17

hyperpolarize in
response to glutamate from photoreceptors,
want light, meaning less glutamate

Question 18

off center bipolar cells

Answer 18

depolarize in
response to glutamate,
want less light meaning more glutamate

Question 19

photoreceptors and bipolar neurons in response to Dim light

Answer 19

lots of glutamate
off center has a large response,
on center has a low repsonse

Question 20

photoreceptors and bipolar neurons respond to brighter light

Answer 20

less glutamate,
on center has a high repsonse
off center has a low response

Question 21

on center bipolar cells excite

Answer 21

on center ganglion cells

Question 22

off center bipolar cells excite

Answer 22

off center ganglion cells

Question 23

fovea

Answer 23

depression in central region of retina best acuity

Question 24

why does fovea have best acuity

Answer 24

no cell layers
the high density of cones
low cone-to-ganglion ratio
large amount of V1 devoted to fovea

Question 25

Visual pathway

Answer 25

ganglion cells in retina -optic nerve -optic chiasm -optic tract lateral geniculate(thalamus(brain)) -optic radiations occipital(or striate) ctx extrastriate ctx

Question 26

Receptive Field

Answer 26

stimuli in the environment (visual space) that increase or decrease the cells response

Question 27

bipolar and ganglion cells in retina have

Answer 27

Concentric Receptive fields

Question 28

on center/off surround

Answer 28

cell is excited by spot of light in its center

Question 29

off-center/on surround

Answer 29

cell is excited by spot of dark in its center

Question 30

Concentric receptive fields

Answer 30

response to light is opposite in center vs surround

Question 31

Ganglion cell types

Answer 31

off center and on center, M cell(movement) and P cells(Pretty), concentric

Question 32

M cells

Answer 32

larger RF more sensitive to low-contrast stimuli stimulus movement

Question 33

P cells

Answer 33

the opposite of M cells sensitive to form and fine detail sensitive to wavelength have color opponent property, center and surround are excited by different colors have spectral opponency

Question 34

Lateral Geniculate nucleus

Answer 34

concentric RF Layer of cells -parvocelluar neurons -magnocelluar Magnocellular and parvocellular layers reflect properties of input M cell and P cells

Question 35

Parvocellular

Answer 35

receive info from P cell spectral opponency

Question 36

Magnocelllular

Answer 36

receive info from M cells

Question 37

LGN projects to

Answer 37

Layer IV of visual of cortex by optic radiation(Axon RF)

Question 38

Layer IV

Answer 38

left and right eye projections are laid out as a series of alternating bonds called ocular dominance columns

Question 39

simple cortical cells

Answer 39

Respond best to an edge or bar of a particular width, orientation, and location

Question 40

complex cortical cells

Answer 40

Respond to the bar of particular width and orientation anywhere in the visual field

Question 41

two major systems of cortical visual areas

Answer 41

ventral processing stream dorsal processing stream

Question 42

Dorsal Processing Stream

Answer 42

where location of objects perception of place, depth, and movement extension of magnocellular pathway(LGN) MT(V5), MST, and other dorsal areas

Question 43

Ventral Processing Stream

Answer 43

what visual identification of objects analysis of form and color extension of the parvocellular pathway V4, IT, and other ventral areas

Question 44

Dorsal processing stream

Answer 44

V1---> V2--->V3--->MT(V5)--->MST--->other dorsal areas

Question 45

Ventral Processing Stream

Answer 45

V1---> V2---> V4---> IT---> other ventral areas

Question 46

V2

Answer 46

illusory contours(triangles)

Question 47

MT

Answer 47

Perception of motion

Question 48

V4

Answer 48

Intermediate complexity, ex. radial stimuli, ceiling fan

Question 49

IT

Answer 49

complex forms and pattern recognition(faces)

Question 50

cones for trichromatic theory

Answer 50

doesn't respond to a specific wavelength responds to a range of wavelengths and peaks at a particular wavelength Small medium and Long

Question 51

spectral opponency

Answer 51

One color excites the center; different color excites the surround ex. Long wavelength excites, Medium wavelength inhibits

Question 52

optic nerve

Answer 52

one eye two fields(left and right)

Question 53

optic chiasm

Answer 53

two eyes two fields

Question 54

optic tract

Answer 54

one eye, one field

Question 55

spectral oppencey