Vision

Question 1

Contain photopigments, which break down in presence of light

Answer 1

Retina has two light-sensitive receptors

Question 2

• is extremely sensitive to light
• function well in dim light, poorly in bright light
• do not distinguish color
• In peripheral retina

Answer 2

Rods contain rhodopsin

Question 3

-requires bright light to function
-do well in daylight, not dim light
-3 types, each responds to different wavelength
-In central retina (fovea)

Answer 3

Cones contain iodopsin

Question 4

-Amacrine cells
-Horizontal cells

Answer 4

Two types of lateral processing cells

Question 5

contact bipolar and ganglion cells

Answer 5

Amacrine cells

Question 6

contact photoreceptors and bipolar cells

Answer 6

Horizontal cells

Question 7

All cell types except ganglion cells generate graded potentials

Answer 7

Ganglion cells fire action potentials

Question 8

how much of the visual world one receptor can see

Answer 8

Receptive fields of rods and cones

Question 9

-receptive fields of GCs are large
-many share a ganglion cell
-enhances their already greater sensitivity to light
-reduces their acuity

Answer 9

Rods

Question 10

-receptive fields of GCs are small
-fewer attach to each ganglion cell
-in the fovea, each has its own ganglion cell
-visual acuity-ability to see details-is high

Answer 10

Cones

Question 11

When light strikes rhodopsin

Answer 11

Retinal is activated

Question 12

-RPE65 is defective; photoreceptors degenerate
-gene therapy can treat this disease

Answer 12

Leber’s congenital optic degeneration

Question 13

-light closes sodium channels
-hyperpolarizes
-turns rods off

Answer 13

Transduction

Question 14

Mary Cassatt

Answer 14

Mach effect

Question 15

Inhibiting one’s neighbors produces contrast

Answer 15

Lateral inhibition

Question 16

1. Retina
2. Optic chiasm
3. Lateral geniculate nucleus (thalamus)
4. Visual cortex (occipital lobe)

Answer 16

Visual pathways

Question 17

1. An on-center/off-surround cell
2. An off-center/on-surround cell

Answer 17

Neurons in retina have two types of receptive fields

Question 18

1. LGN (thalamus)
2. Visual cortex (V1-V5)
3. Secondary Visual Cortex

Answer 18

Three stages of vision processing

Question 19

-Parvocellular
-Magnocellular
-Koniocellular

Answer 19

LGN has 3 cell types

Question 20

-small cells
-small receptive fields

Answer 20

Parvocellular

Question 21

-large cells
-large receptive fields

Answer 21

Magnocellular

Question 22

-layers with very small cells
-between main layers

Answer 22

Koniocellular

Question 23

Where pathway

Answer 23

Parietal Cortex

Question 24

What pathway

Answer 24

Infero-temporal Cortex (IT)

Question 25

Where most visual information first arrives

Answer 25

Primary visual cortex (V1) in occipital cortex

Question 26

Brain maps of visual space are mostly devoted to

Answer 26

Fovea

Question 27

-simple cortical cells -complex cortical cells

Answer 27

Brain maps of visual space are mostly devoted to the fovea

Question 28

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

Answer 28

Simple cortical cells

Question 29

Respond to a bar of a particular width and orientation, but it may be anywhere in the visual field (location independent)

Answer 29

Complex cortical cells

Question 30

Classified as simple or complex, depending on their receptive fields

Answer 30

V1 cells are

Question 31

receive input from neurons in the lateral geniculate

Answer 31

simple cortical neurons

Question 32

receive input from simple cortical cells

Answer 32

Complex neurons

Question 33

Perceives objects so it is needed to form all visual images

Answer 33

V1 (primary visual cortex)

Question 34

perceive complex form

Answer 34

V2, V4, and the inferior temporal lobe

Question 35

Specialized for motor perception

Answer 35

V5

Question 36

Organized in columns and slabs

Answer 36

V1 is

Question 37

A region of cortex with greater synaptic input from one eye

Answer 37

Ocular dominance column

Question 38

Color, shape, location

Answer 38

3 inputs of vision at once

Question 39

-Parallel processing -V1 breaks down the visual image into components

Answer 39

Primary Visual Cortex

Question 40

Breaks down the visual image into components

Answer 40

V1

Question 41

-“fills in the gaps” -much of vision is extrapolating (predicting) from what is actually ‘seen’

Answer 41

V2

Question 42

-respond to concentric and radial stimuli -involved in color perception

Answer 42

V4

Question 43

A regular polygon of infinite number of sides

Answer 43

Circle

Question 44

-Spatial location and action -where pathway

Answer 44

Dorsal Pathway

Question 45

-characteristics of objects -what pathway

Answer 45

Ventral Pathway

Question 46

-dorsal pathway -MT, V2

Answer 46

Parietal lobe

Question 47

-ventral pathway -V4, V2

Answer 47

Temporal lobe