lecture 1b) visual development Flashcards
why do we focus on infancy when studying visual development
because there are very rapid changes i nthe first 2 years of an infants life and changes in one area enable changes in other areas
and helps us understand which abilities are inante and which have to be learned through experience
what is a major struggle for studying infants
studying infants are different than methods for studying older children beacuse older can communicate more clearly with adults
true or false: at birth, an infants vision is almost non existent and barely fucntional
false, they can visually scan their environment and pause tot look at things
what are the 2 major methods in infant research
1) preferential looking paradigm
2) habituatiton paradign
what does the preferential looking paradign take advanttage of
takes adcvantage of infant’s preference to look at “interesting” things
explain the general idea of the preferential looking paradigm
1) present the baby with 2 stimuli side by side att the SAME TIME
2) if the baby lookings longer at one sitmuls that the other tthan tthat means that 1) they can distinguish between the two and have a preference for one over he oher.
what does tthe pref looking paradign assess
assesses infants natural preference for stimuli
what is a major limitation of tthe pref looking oarasign
babies cannot point therefore you need to try to deduce where they are kooking/focussing
=solution= use eye tracking devides
in the pref looking paradigm, if the baby looks longer at one stim than the other, what does that mean (2)
1) thye can distinguish beetween the 2
2) they have a preference for one over the otther
trtue or false: the habituation assesses the preference of an infant
false, assesses the ability to distinguish
what dose the habituattion paradigm take advantage of
the babies nattural preference for novelty (new things)
explain the habitutaion paradign generak
1) repeadely present infant with a stimulus until they habituate to it (ie: slowed, changes or stopped resoonse, looks at it less, gets bored)
2) present habituated “old” stim witth a new sttim
3) if baby changes its reaction to the new stim (dishabituation) it can telel the difference betweene the ttwo but if it looks equally at both, it cannot
what does the habittuation paradigm assess
the infants ability to discriminate b/w sttimuli
what is the habituation phase
repeatedly present infant with a stimulus until they habituate to it
explain the teset of the habituation paradigm
present thee habituated “old” stimulus with a new stim
if the baby changse its reaction to the new stimulus (dishabittuation), it can tell the difference between the two
what does it mean if the baby looks at both objects equally in the habituation paradigm
it means they cannot disttinguish between the 2
what is the def of visual acuity
sharpness of visual discrimination
how is visual acuity asseessed in children
by preseention a successtion of paddles with increasingly narrower stripes and narrowing gaps betweeen them until tthee infanct can no longer disgttinguish between srtipped paddle and plain gray one
true or false: at birth, infants have poor visual acuity
truee
since infants have poor visual acuity, do they prefeer tto look att images with high or low visual contrastt
high
true or false: infants are capable of distinguishing between stim with lower and highere sensitivities
false, they dont discriminate bettween stim with lower contrast sensitivities
be able to undersatnd the visual acuity witth paddles ttest
good
why do infants have poor visual acuity when they are younger
due to the immaturity of the cone cells in infants retina (light sensitve neurons involved in seeing fine details and colours)
when do chuldren develop adult like acuity
at 8 months
true or false: at 7 months, children have adult like acuity
false, 8 months
be able to disinguish between diffeerent moths and the development of visual acuity
,
what is the colour perception at 1 month
black and white
what is the colour perception at 2 month
colour vision appears
what is the colour perception at 5 month
perceive colour categories simular to adults
when do infants see black and white
1 month
when do infants have colour vision appeaer
2 months
when do infants perceive colour categories similar to adults
5 months
do infants categorize colour the same way adults true?
kinda,, they are able to distinguish thee diff btween green vs purple but not to change in colour. within the same cateogry
trtue or false: from birth, infants can scan their visual environment and pause to look at something threfore ehave no issue tracking moving stim
false
infants can scan their visual environment and pause to look at something BUTTT
they have troublee tracking moving stim
why do infants have trouble tracking moving stimuli
bcause eye movements are ejereky
at what age are infants able to smoothly track slow moving objects
4 motnhs
at what age do infants deevelop adult like visual scanning (smoothly follow objeects)
8 montths
what is the quality of tracking stim as a new born
have trouble tracking moving stimuli because eye movements aree too jerky
what is the quality of tracking stim as a 4 momth old
smoothly ttrack slow moving objects
what is the quality of tracking stim as a 8 month old
they have adult like visual scanning and can smoothly follow objects
wha causes improved visual scanning from infant to 8 months
brain maturation
why is the ability to visual scan important
because it is one of the few ways that infants have control over what they observe and learn
(ability to be autonomous for baby) active child)
true or false: newborns show a preference for faces (face like stim)_ overe non face like stim
true e
do infants prefeer right side up faces or invereted
right side up
explain why there was a hypothesis that there was a special face preception mechanism
because there is a part of the brain in the temporal cortex (fusiform face area) specialized in facial reconigztion
what is the hypothesis for why infants are drawn to faces
infants have a general bias for sttim that are more “top heavy” vs bottom heavy
how did they prove that baboese have a bias for top haevy stim
used preferential looking paradigm and showed reg faces, upside faces, scrambled top heaevy and scrambled body heavy
if faces were “special” ie (innate mechanisms) what should the beehavior of the baby be when shown the 4 different faces
the babies should always prefer to look at the upright non scrambled face
if faces were not special ie (general bias for top heavy mechanisms) what should the beehavior of the baby be when shown the 4 different faces
babies should prefer upright face AND scrambled top heaevy faces (with no preference btween thee two)
true or false: there was a preef for the upright fac eovere the upside down facee
true
was thtere a prefernecee for top heavy scrambled or bottom heavy
top heavy
what was the behavior of babies when shown the upright face AND the top heavy config next to each other
there was no preference bettween the two showing that the preference for the faces simply result of general preference for stimuli that are top heavy rathere than bottom heavu (ie no special mechanism)
tru or false: babies cannot recognize mom;s face
false, they quickly learn how to recognize and prefer and only a few days after birtth, babies prefer theeir mothers face compored to otther women
what happens over the 1st year of life in terms of faces
infants become face specialists
what does it mean to say that infants become facial specialists over the first year of life
meaens they are better at distinguishinh between faces thatt are frequently experienced in ttheir enviroment
do. we have the same ability to distinguish between monkey faces as we do for humans
no , we have a harder ttime distinguishng beween money faces beacuse they are nott part of our normal enviroment
what is the evidence that oveer the first year of lifee, infants become face specialists
9 montths old and adults can distinguish between human faces but struggle to distinguish between 2 monkey faces whereas
6 month olds are equally good at disttinguishing human and monkey faces (generalis)
true or false: at 6 montths, infants are face specialistst
false, they are generalists at tthis point
at 9 months they are specialists
what is perceptual narrowing
tuning of perceptual mechanisms to the specific sensory inpits that infants eencountre in their daily lifee (will specialize in things you se eoften)
explain percepttual narrowing.
there is a decline in the ability to distinguish stimuli that ar enot present or relevant to the infants enviromentt
what is perceptual narrowing the reseult of
synapttic pruning
exeplain synaptic prunning
During synaptic pruning, the brain eliminates extra synapses.
= not wastee neural ressourceese on distinguishing non important things not in our normal environemnt
what are some examples/evidencee of perceptual narrowing in face perception
infants becoming face specialists
infants demonstrate the other race effect
what is the other race effect
people find it easier to distinguish between faces of individuals from their own. racial group rather than between faces from tother racial groups
explain how they showed otther face effect in infactns
got caucasian kids and habituated them to their own face or to another face and then presented the habituated face wih a new face from the same ratte
results=
3 months old: distinguish between faces of all faces
9 months old: can only distinguish between faces of own race
what were the results of the other race effect tese
3 months old: can distinguish between facse of all races
9 months old: can only distinguish between faces of their own race
what is the other race effect evidence of
perceptual narrowing
what is the face specialists evidence of
perceptal narrowing
is the other race effect innate and why or why not
not innate but rather due to exporsure effect
during few months of life, 96% of faces that babies are exposed to are to females of their own race
trtue or false: even if iinfant is equally exposed to faces of different races, they will still show other race efefect
false, they will not show ORE
is facial perceptin in ASD kids tthe same as normal ?
no , ASD have difficulty with face perception (rathre not look at eyes) -
true or false: toddlers with ASD preefere to look at people over shapese
false, othere way around (
if infants have prefererence for non faces, what could this be an indidcator of
ASD
true or false: from birth, infatnts have a preference. for faces, especially their mothers
true
is face preference innate
no it is not innate but rather a result of general preference for top heavy stimuli
true or false: at 8 months, infants become face speecialists as a result of the other race effect
falsee, 9 months and perceptual narrowing
