perceptual development Flashcards
where is the fovea in our eye?
center of our retina
what does fovea do?
focus and facilitate sharp vision
what is bifoveal fixation?
when we fixate on an object, the image of the object is centered on the fovea of each retina.
what are the 2 steps in focusing on an image?
- getting the image onto the fovea
- processing the image
why is it difficult for babies to get an image onto the fovea? talk about:
1. converge
2. response time
3. blurred images
- babies’ eyes don’t always converge on 1 object like adults’ do. each eye sees something different.
- babies’ focusing response is slow and imprecise.
- image is focused behind retina, causing blurred images.
fill in the blanks:
the 2 types of photoreceptor cells are _____ and ______.
adult fovea contains tiny spots with 50,000 _______, which are responsible for daylight vision and ______.
infant fovea is twice as _____ and littered with other cells. cones are _________ and look different than that of adults’ (like _______). cones are less ________ and more spread out.
rod; cone
cones;color
wide; immature; stumps; concentrated
how is infant acquity measured?
- measured by smallest black and white stripes that can only be detected under high constrast
- infants prefer stripes to gray patterns thus will look at them if they can see it
true or false: infants’ visual acquity is well developed and continues developing slowly as they grow.
false. poor visual acquity but develops quickly. they see 30x worse than adults with perfect vision.
perfect eyesight is 20/20 or 6/6.
what is an infant’s eyesight?
20/600 or 6/180.
babies see from 6m away from the chart, the same thing adults do at 180m away from it.
assuming babies are looking at a ruler from 30cm away. how would they see the measurements at birth, 2 mths, 4 mths, 8 mths, 4/5 yrs?
birth - .1 inch
2 mths - .05 inch
4 mths - .025 inches
8 mths - .0125 inches
4 to 5 yrs - adult level
do babies have good color vision at birth?
no
color vision develops rapidly, much like visual acquity. how long does it take for a baby to develop adult-like color vision?
3 to 4 mths
what color combinations can babies see at birth?
grey vs red
grey vs yellow
grey vs green
green vs red
what color combination can babies see at 1 month?
grey vs blue
what color combination can babies see at 2 months?
green vs yellow