Vision

Question 1

how do we see

Answer 1

lights reflects from an object and falls on the cornea
light travels through the aqueous humor to the lens
light travels through the vitrous humor to the retina
most light falls on the fovea/foveal pit

Question 2

what does the fovea have

Answer 2

has most of the light receptors

Question 3

types of photoreceptors

Answer 3

rods
cones

Question 4

what do photoreceptors contain

Answer 4

light sensitive pigments

Question 5

what happens to light sensitive pigments when stimulated

Answer 5

change shape

Question 6

what does the changing shape of photoreceptors do

Answer 6

generates electrical nerve impulse

Question 7

how does the electrical nerve impulse get to the brain

Answer 7

travels along the optic nerve

Question 8

how many
rods?
cones?

Answer 8

rods: 120 million
cones: 6 milllion

Question 9

what kind of information do rods give?

Answer 9

achromatic

Question 10

conditions cones operate in

Answer 10

photopic
-higher illumination

Question 11

where are the cones concentrated

Answer 11

fovea

Question 12

conditions rods work in

Answer 12

scotopic
-low light, no colour

Question 13

three colour sensitive pigments in cones

Answer 13

red: p
green: gamma
blue: beta

Question 14

what is visual adpatation

Answer 14

decrease in responsiveness under constant stimulous

Question 15

what kind of stimuli does the nervous system pay more attention to

Answer 15

changing

Question 16

example of visual adaptation

Answer 16

walking into a dark room and after a while being able to see things

Question 17

how old are babies when they have been seen to prefer faces

Answer 17

2 days

Question 18

what happens to the foveal receptors after birth

Answer 18

density and cone outer segment length increases

Question 19

when does the fovea pit develop dramatically vs when it is fully developed

Answer 19

4 months
4 years

Question 20

when is the critical period of early visual developement in humans

Answer 20

3-8 years
period od neural plasticity

Question 21

how is colour perception influenced (3)

Answer 21

physcial and chemcial compoisition
spectral composition
spectral sensitivity of an individual

Question 22

M-cone pigment

Answer 22

green

Question 23

L-cone pigment

Answer 23

red

Question 24

S-cone pigment

Answer 24

blue