Area 3- child Flashcards
what is topic 3
perceptual development in children and how this can be studied in animals
what does studying behaviour in animals and humans show
evolutionary links so behaviour must be innate
what is perception
organisation or interpretations of sensory information
whats the main debate of perception
Nature/nurture - is our ability to perceive something innate or learnt
what are the 2 cognitive concepts
top down processing - past experiences- brain effect what being seen - expectation
bottom up processing -data driven
what is the nativist view of perception
humans are born with at least some genetically predisposed perceptual abilities, even if they don’t appear immediately they will later
what is the constructivist view of perception
perceptual abilities develop through learning as we make sense of sensations we experience- born with little or no perceptual abilities
what is the interactionist view of perception
born with strong disposition to develop certain abilities important to survival but these develop in response to environment (born with tools)
what is depth perception
3-dimmensional- ability to perceive depth or distance promotes survival - prevents falling
occurs because brain can interpret depth cues
whats mean by constancy
we perceive something as constant even if it changes angle or distance ( something may look different by we know its the same)
what are the 3 constancies
colour e.g, sun hits grass we know is not light green and dark green grass
shape- angle
size - distance
what are the 4 depth cues
superimposed- layered
linear perspective- lines get closer together to show distance
height in plane- distance e.g., beach is halved for sea and sand
texture gradient- less detail further away
who research the nature of perception
Tom bower
what did tom bower do
tested babies ability to perceive depth
8-17 days old
2 cubes, 1 large cube 20 cm away and 1 small cube 8 cm away
images projected onto retina would be same size
what did tom bower find
babies raised their arms in response to closer object - distinguish between 2 objects as they knew which one way closer - have some degree of depth
who researched the nurture of perception
William Hudson
what did William Hudson do
gave several 2D drawings to south African children and adults who had been schooled or unschooled
e.g., hunter appears to be holding spear in general direction of elephant or antelope but elephant is smaller than antelope and on higher ground suggesting it is further away
what did William Hudson find
schooled participants knew it was the antelope but unschooled chose elephant- suggests depth is partly learnt as if it was present at birth the unschooled would have guessed correct
what did Fantz do
conducted famous study which he showed new born babies 2 versions of faces normal and scrambled
what did Fantz find
found babies looked at image on left (normal) than other images - young babies no preference for correct image over a scrambled one but they did at 3 months
one month they can see edges
2 months they can see depth
2/3 months- centre of face probably controlled by cerebral cortex
perception is there but appears later- 3 months
what is preferential looking
babies look at things they find interesting - study in animals shows that it is universal- measured amount of time spent looking at 2 stimuli
how did Fantz gather inter-rater reliability
videoing the babies when presented with photos
what’s meant by babies perception becoming habituated or dishabituated
babies spend longer looking at something new but when they are used to it, it becomes habituated and look elsewhere
how does an EEG measure perception
geodesic sensor net secured by cap but on head to measure brain waves and spikes in response to visual stimuli
how does dark rearing measure perception
raising animals in dark environments
dark- deprived of perceptual stimulation
if capable same as light reared, suggests its innate
approximately how many times does the heart beat a minute
70
what is the function and structure of medulla oblongata
controls heart rate- controlled by autonomic nervous system
two centres - one that increases heart rate, one decreases
how is heart rate increased
sympathetic nervous system by accelerator nerve
how is heart rate decreased
parasympathetic nervous system - vagus nerve
what are baroreceptors
pressure detects changes in blood
found in aorta, vena cava, carotid arteries (neck)
what are chemoreceptors
detects changes in levels of chemicals in blood
found in aorta, carotid arteries and medulla
what happens when blood pressure increases
baroreceptors detect change and send impulse to medulla oblongata to decrease heart rate by passing impulse along parasympathetic neurones ( vagus nerve) to SAN
what happens when their is a high carbon dioxide concentration in the blood
chemoreceptors send impulse to medulla oblongata which travels down sympathetic neurones ( accelerator nerves) to increase heart rate- get rid of waste product by transporting it to lungs for exhalation
how do hormones control heart rate
adrenaline and nor-adrenaline increase frequency of contraction produced by SAN, speeding up heart rate
what did Yerkes do in background
found aquatic turtles have poorer depth discrimination, other studies shows innate in rats
what is the first aim of Gibson and walk
to investigate the ability to perceive and avoid a drop is learned through experience or part of a child’s original blueprint
what is the second aim of Gibson and walk
discover point of development at which they perceive depth and whether this varies in different animal species - does it become before/after/same time as being able to move independently
what is the third aim of Gibson and walk
test 2 visual cues- which is more important in depth perception- density of pattern in environment (texture), motion parallax ( distance objects moving slower than closer)
what is the method of Gibson and walk
lab experiment - repeated measures
IV- whether babies were called by mother across shallow or deep side
DV- whether or not baby crawled across visual cliff
studying same with animals
what is the sample of Gibson and walk
36 babies, 14 months they can move independently
other animals such as cat, rat, aquatic turtle, chicks, lambs, dogs,
what is the procedure of Gibson and walk
visual Cliff with glass cover - patterns less detailed further away
babies/animal paced in centre and observed if they walk to shallow end or deep end
reflections removed as light was shone from under
texture gradient- texture of deep side was finer
motion parallax- squares on shallow move faster as they crawl across - closer
is it bias jsut being mothers calling babies
it is an appropriate sample as that time mums were known for spending most time with children-temporal validity
what were the results of babies
27 children crawled to shallow side
3 crawled to deep side
many crawled away from mother on cliff side which and babies cry because they couldn’t get to her
often peered through or reached out but didn’t crawl
what are the results of animals
chicks less than 24 hours - hop onto shallow side
no goat, lamb step onto shallow
when placed onto deep- they refused to put feet down
when drop reduced ( more texture) to around 30 cm - happily go across
rats- moved normally - used whiskers as depth perception
what are conclusions of Gibson and walk
when babies can move independently they can perceive depth
motion parallax is a key depth trigger
animals can discriminate depth
depth perception of chickens, goats, kittens is quick
rats and kittens uses cues from whiskers to perceive depth
aquatic turtles have good depth perception, it is innate in rats, maturational in kittens
