Susie Chapter 6

Question 1

light enters the eye through the __ and is focused, by the __ and the __, on to the __ at the back of the eye.

Answer 1

pupil, cornea, lens, retina

Question 2

the pupil is surrounded by a pigmented __ that can expand or contract, making the pupil larger or smaller as light levels vary.

Answer 2

iris

Question 3

how many photoreceptors are there once focused on the retina?

Answer 3

125 million

Question 4

this is the most numerous photoreceptor, responsible for black and white, and movements in low light conditions

Answer 4

rods

Question 5

this photoreceptor is responsible for color vision

Answer 5

cones

Question 6

the conversion of light into electrical signals in the rods and cones is called…

Answer 6

phototransduction

Question 7

this is where the fibres of nerve meet, half of them cross to the other side, while the other one stayed uncrossed.

Answer 7

optic chiasm

Question 8

the bundles of fibres from both eyes form the …

Answer 8

optic tracts

Question 9

the first relay station on the optic tracts is called…

Answer 9

suprachiasmatic nucleus of hypothalamus

Question 10

the second synaptic relay station on the optic tracts is called…

Answer 10

lateral geniculate nucleus

Question 11

the neural representation has inputs from each eye and so the cells in the visual areas at the back of the brain can fire in response to an image in either eye is called…

Answer 11

binocularity

Question 12

the region of retina over which the cell will respond to the prefered kind of image is called…

Answer 12

receptive field

Question 13

in this stage, the neurons respond best to lines or edges in a particular orientation. it is responsible for the conscious experience of vision. it also distribute signal to different areas in the brain.

Answer 13

V1

Question 14

this stage is responsible for the perception of colour

Answer 14

V4

Question 15

this stage is responsible for the motion of visual stimuli and perceived motion (by the observer).

Answer 15

V5/MT

Question 16

reactions to perceptual targets that are genuinely ambiguous, the observer is placed in a state of indecision, constantly fluctuating from one interpretation to another.
ex. Necker cube

Answer 16

binocular rivalry

Question 17

this person contributed to the understanding of how the visual system develops. this includes interactions between different parts of a pathway in the embryonic brain, and axons growing down from the developing cortex to meet other fibres before growing up to the cortex.

Answer 17

Colin Blakemore

Question 18

these two people discovered orientation selectivity, the columnar organisation of cells and the plasticity of the system in the visual cortex, leading them winning Nobel prize.

Answer 18

David Hubel and Torsten Wiesel.

Question 19

what visual field deficits would you expect in someone with a stroke destroying their left optic nerve? (blue-red, blue-red)

Answer 19

black-black, blue-red

Question 20

what visual field deficits would you expect in someone with a stroke destroying their left visual cortex? (blue-red, blue-red)

Answer 20

blue-black, blue-black

Question 21

what visual field deficits would you expect in someone with a pituitary gland tumour? (blue-red, blue-red)

Answer 21

black-red, blue-black

Question 22

blindsight is associated with damage in which part of the visual cortex?

Answer 22

V1

Question 23

the axons of what cell type form the optic nerve?

Answer 23

ganglion cells

Question 24

name the coloured patchwork design used to study how the brain processes colour.

Answer 24

mondrian

Question 25

which two parts of the eye focus light on the retina?

Answer 25

cornea, lens