Unit 4 part 1 The first two years of life Flashcards
What is sensation?
Detecting elementary properties of a stimulus
sensation -> perception(and add information) = cognition
Audition
-> develops in the final trimester of prenatal development
-> baby can turn head towards noise
-> Assessed with Otoacoustic emission
-> (w/ development of cortical areas) 4mos attend and develop expectation of speech, used to native language
What is a Otoacoustic Emission (AOAE) test?
With a soft-tipped earpiece, a gentle clicking is played (shortly after birth)
no response could be that:
- child unsettled
- background noise
- temporary fluid blockage
Vision
Birth -> 20/600 vision
eyes are used independently, often cross-eyed (not developed binocular vision)
(2m to 4m binocular vision develops=depth perception)
2m -> stare at face and smile in response
3m -> look at eyes and mouth - discriminates an angry face to smiling
6m -> 20/60
9m -> 20/20
Depth perception and The Visual Cliff
-> ability to judge the distance of objects from one another and from ourselves (understanding of layout guides Moto activity)
-> crawling BABIES: crossed the shallow end but avoided the deep side
-> this studies can also used in the social referencing studies: they use adults emotional cues to regulate their behavior
Limitations of Visual Cliff Studies
-> it can only be done with crawling babies
Solution: Reaching behavior or defensive reactions (approaching light) can be done as early as 2w, were already engaging in reaching or defensive behaviours
Preference technique
presentation of two stimuli, the one that is given the most attention is considered to be a PREFERENCE of the child
newborns-> images with defined patterns NOT random
Object consistency
refers to the perception of an object as having a constant size, even when its distance from the observer changes (a ball becoming smaller as it moves away from us)
Present since birth - appriciating shapes, luminosity, and colours
Shape constancy
Ability to perceive objects as having the same shape even when its orientation to observer changes (a door moving inwards and outwards)
Externality effect
tendency of infant to direct attention primarily to the outside of a figure (little time inspecting internal features) diminishes after age 1
-> Newborns: no innate preference to face
-> under 2m: concentrate on around face
-> over 2m: internal features explored (eyes)
-> 3m: mother’s face discriminated
-> 4m: interested in eyes, nose, mouth
-> 5m: facial schema diversity and individualize
-> 5-6m: facial expressions of emotions and react accordingly
Motor Development
develops the first 2yrs - Motor abilities weaker than sensory
essential for interacting with environment
-> shortly after birth motor control develops in cephalic-caudal and proximo-distal direction
Voluntary movement
Essential for effectively interacting with the environment
-> requires coordination between BRAIN areas that communicate with skeletal muscles via SPINAL CHORD (takes time for development)
-> motor control depends on reflexes that mature in conjunction with stimulation from the environment
Gross-motor development
LARGE movements that coordinate many parts of body
infants-> 1st control head -> upper body -> arms -> legs and feet
(cephalon-caudal and proximo-distal direction)
Head and Hands
head: can be moved from birth, at 1-4ms babies lift their heads in tummy time. after 4m can sustain head sitted
hands: newborns have the palmar grasping reflex, 3-4m grab moderate sized objects, 7-11ms coordination for lifting small objects, 15m can build towers of blocks
Baby locomotion
3ms - babies can turn around
1-4m - babies can sit supported
5-9m - babies can sit unsupported
5m - can drag themselves with arms
5-11m - can lift themselves to crawl on all fours and pull themselves to a standing position
7m - stand + support
11-12m - stand no support
10-17m - stands and walks
18-30m - run and jump
Fine motor development
Managing small body movements, increased control over the hands and fingers
-palmar grasp reflex is not controlled
-pre-reaching= swiping of objects no coordination
FOR: exploration and understanding object properties and the physical world
What is ulnar (palmar) grip and pincer grip
babies first grip using ulnar grip, between fingers and palms
then at 9-10m babies show more mature pincer grip, coordination of forefinger and thumb
How does correlation between development and myelinisation?
Myelinisation is the reason to why motor control occurs.
myelin coats neurones which increases the efficiency of communication between the brain and skeletal muscles
(cephalocaudal and proximal distal)
begins in prenatal development in:
spinal cord -> hindbrain -> midbrain -> forebrain
slows down in adolescence
Piaget’s (1962) Cognitive theory,
what are the four main stages?
1 - birth to 2y - sensorimotor intelligence
2 - 2y to 7y - pre-operational thought
3 - 7y to 11y - concrete operations
4 - 11y to adulthood - formal operations
this is a invariant developmental sequence
sensorimotor intelligence
b to 2y
schema created via sensing with motor abilities -> allow interaction with environment
transition: reflexive -> reflected
-> it is progressively built from reflexes until inidividuals are able to interact intentionally and object permanaces.
Stage only ends when child can handle ability to handle mental representations of objects
Phase 1 and 2 of sensorimotor intelligence
1 Reflexive schemas - use of reflexes (b to 1m)
-> 1st sucking reflex
Towards the end baby lifts head to seek breast or bottle for feeding
-> They are limited to exercising innate reflexes and assimilating new objects into reflexive behaviors
2 Primary circular reaction (1 to 4m)
-> infants start to repeat actions they learned directed to their own body
-> frequency of repeating allows more deliberate actions
Phase 3 of sensorimotor intelligence
3 Secondary circular reactions (4-8m)
Quasi-intentional behavior -> schemas directed towards the exploration of environment. actions produce desirable results
-> not folly intentional response, because the interesting result it produced what discovered by chance
babies know they are not objects and can manipulate the environment
Phase 4 of sensorimotor intelligence
4 Coordination of secondary schemas (8-12m)
Intentional and goal-directed behaviors appear
they combine two or more actions making a complex behavior
goal-directed because the component behaviors do not result directly in a positive outcome
- they separate means from ends
- develop anticipator behavior
phase five of sensorimotor intelligence
Tertiary circular reactions (12-18m)
-> Babies begin to deliberately and systematically vary his behaviors for new patterns and effects
-> Repeats a circular reaction and introduces variations, trying to provoke new results
-> trial-and-error exploratory = shows infant’s active curiosity
Phase 6 of sensorimotor intelligence
The beginning of mental representation (18m-2y)
-> internalise beh schemes to form mental images/routes
-> can experiment mentally to for-see consequences - make decisions without needing tangible examples
-> intelligent behaviors involving mental representation appear, NOT problem solving YET
–> Symbolic or function = ability to handle mental representation to think or act about the world internally and not merely externally.
Object permanence: what is it?
objects continue to exist when they are no longer visible
experiment: removing a blanket to retrieve what lies underneath involves understanding object permanence
Object permanence: Piaget’s early stages
1-4m - infants will not search for objects hidden from view
4-8m - infants will only retrieve partially concealed objects
Object permanence: Piaget’s later stages
8-12m STILL not complete
obsv on his 10m old daughter
-> he hid her toy under a mattress in location A. She is able to find it, but he then takes the toy from her once more and hides it in location B. But she looks for the toy in location A having seen him hide it.
Object permanence: A-not-B error
this is typical 8-12m
Piaget suggests that this demonstrates that infants believe that their behavior determines where the object will be found
–> (they think they’ll find it where they previously found it and not where they last saw it)
at 12-18m the concept of object permanence improves
Object permanence: invisible displacement
the understanding of object permanence is still incomplete: infants do not understand invisible displacements until 18-24 months
