chapter 5: perception, knowledge and action in infancy Flashcards
cognitive development
the development of behaviors related to perception, attention, thinking, remembering and problem-solving
mental representations
an internal description of aspects of reality that persist in the absence of these aspects of reality
visual acuity and level at birth
the ability to make fine discriminations between the elements in the visual array, 1/30 of perfect vision at adulthood
visual accomodation and level in infancy
the ability to focus on objects irrespective of their distance to the eye, poor
when do acuity and accomodation improve
in the first 6 months
how can perception in infancy be studies
visual preference method or habituation techniques
visual preference method
infants are shown two objects side by side, the amount of time they spend looking at each one is compared - implies discrimination
habituation techniques
the process by which attention to a stimulus gradually declines over time and recovers when a new stimuli is presented
shape perception in newborns
capable of perceiving differences between simple shapes (cross, triangle, square, circle)
problems for infant perception
they might be discriminating between the forms on the basis of the presence of a single feature in one stimulus and its absence in others
experiments for perception in newborns - what are they discriminating actually
can discriminate between line orientations, 4-month-olds could discriminate on the basis of angular relationships but at 6-weeks couldn’t
size constancy
understanding that an object remains the same size despite its retinal image size changing as it moves closer to or away from us
shape constancy
understanding that an object remains the same shape even though its retinal image shape changes when it’s viewed from different angles
experiment with size constancy
newborns look longer at an object of different size than at the same object at a new distance even when the new object is placed at a distance that leads to the same retinal image - respond to true change in size
retinal image size
the size of visually perceived object on the retina of the eyes, will vary depending on the real size of the object and its distance from the observer
object unity
understanding that an object is whole or complete even though part of it may be hidden
experiment with object unity
habituated 4-month-olds to rod moving back and forth behind the box, looked longer at separate parts - only when the rod moves (common motion)
at 2 months - only showed the same results if the occluding box was made narrow
when can newborns show object unity
when the stimuli are presented stroboscopically
object moves behind an occlude experiment
habituating infants to an event in which an object moved back and forth disappearing behind an occlude in the central part of its trajectory
6 months - perceive it as continuous
4 months - only when the occlude was narrow or the object was out of sight very briefly
2 months - perceive it as discontinuous
subjective contour
when only parts of an object are presented, the remaining contours are filled in, in order that the complete shape can be perceived
subjective contour experiment
habituated to a subjective contours of a square and then measuring looking at a real square vs other object
doesn’t exist at birth but does 4+ months
face perception experiment
facial features in the right places vs in a jumbled array vs no features but same overall brightness
preference for face in the 1st month
criticism - facial arrangement contained more info around the edges
later for 2 and 4 months
what happened when they moved schematic stimuli int he visual field of newborns
followed faces longer and further
what are the two mechanisms behind face preference
two process account - innate subcortical mechanism (CONSPEC) that leads them to attend preferentially to facies of the same species + after second month - CONLERN - specialization
preference for certain properties of stimuli that aren’t face specific (top heavy stimuli)