CDfirst 2yearscognitvedevelopment

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Cognitive Development
In the First Two Years
Jean Piaget: Period of
Sensorimotor Intelligence
 Piaget (Swiss, 1896-1980) believed that
infants were smart, active learners
 Also that they adapted to experience
 Called infancy (birth to 24 months) the
sensorimotor period because infants
learn through their senses and motor
skills
 Period subdivided into 6 sub-stages
Stages 1 & 2: Primary circular
reactions
 The brain and senses interact involve
the infant’s own body (birth to 1 month)
 Sensation, perception and cognition
cycle back and forth (Piaget’s circular
reaction)
 Stage 1: stage of reflexes--the reflexes
of grasping, rooting, staring, listening-are adapted into deliberate actions
 Sensation becomes perception
Stage 2 of Primary Circular
Reactions: acquired adaptations
 Accommodation and coordination of
reflexes (1-4 months)
 Example: sucking becomes adapted-infant sucks a pacifier differently than a
nipple
 This indicates thinking: the infant has
figured out that the pacifier is something
different than a bottle
Stages 3 & 4: Secondary Circular
Reactions
 Involve the infant’s responses to objects
and people
 Stage 3 (4-8 months) includes making
interesting sights last: it is responding to
people and objects, as in clapping hands
when mother says “Patty-cake!”
 Also includes responding to toys
 The sight of something that delights the
infant will trigger active efforts for
interaction
Stage 4 of Secondary Circular
Reactions
 New adaptation and anticipation
 Infant becomes more deliberate and
purposeful in responding to people and
objects
 Example: putting other’s hands together
in order to make her start playing pattycake
 Thinking is more innovative--babies are
thinking about a goal and how to reach
it
Goal-directed behavior is a big
deal
 This behavior stems from
 1) an enhanced awareness of cause and
effect
 2) memory for actions already
completed
 3) understanding of other people’s
intentions
 This new awareness coincides with new
motor skills that are needed to achieve
goals
Object Permanence:
 Piaget thought babies attain this at 8
months
 Object permanence refers to the
awareness that objects or people
continue to exist even if they cannot be
seen, touched or heard
 Probably occurs as early as 5 months,
new research indicates it happens
somewhere between 4 and 6 months
Stages 5 & 6: Tertiary Circular
Reactions
 Second year of life
 Feedback loops involve active
exploration of the environment and
experimentation
 “Little Scientists” in stage 5, (12-18
months) new means through active
experimentation
 Examples: putting a teddy bear in the
toilet and flushing, or squeezing all the
toothpaste out of the tube
Stage 6:
 New means through mental
combinations (18-24 months)
 Considering before doing provides the
child with new ways of achieving a goal
without resorting to trial-and-error
experiments
 This will hopefully involve
remembering that flushing teddy down
the toilet resulted in an overflowing
toilet the last time it was tried
Stage 6:
 Using mental combinations involves
intellectual experimentation that
supersedes active experimentation
 Children can now combine 2 ideas: they
know a doll is not a real baby, but also
that the doll can be belted into a stroller
and taken for a walk
 They begin to think about consequences
 They also can defer imitation (copy
behavior they saw hours or days before)
Criticism of Piaget:
 Piaget underestimated infant cognition,
probably because he based his ideas on
observations of his own children, not of many
children from many cultures
 Modern research includes “Habituation” or
repeated exposure to get used to an object or
event
 Then sensitive physiologic measurements are
used to record reactions
 Using this, even 1-month-olds can be
demonstrated to differentiate between sounds
More criticism:
 The brain and its growth can now be
measured by fMRI, which measures
electrical activity in the brain that
indicates firing of neurons
 This has shown us that the brain has a
huge amount of early growth, then trims
off dendrites
 Also shows that growth continues after
the first 2 years
 Piaget didn’t have this technology
Summing up Piaget:
 Piaget discovered that infants are very
active learners
 Described this as Sensorimotor Period
 Substages: Circular Reactions
 Lacked modern technology
 Also used a restricted sample that may
have led him to place some behaviors
later than is true with the majority
Information Processing Theory:
 A perspective that compares human
thinking processes, by analogy, to
computer analysis of data, including
sensory input, connections, stored
memories, and output
 Many versions of this theory
 All share the belief that a step-by-step
description of the mechanisms of
thought adds insight to our
understanding
How it works:
 Human information processing begins
with input picked up by the senses
 It proceeds to brain reactions,
connections, and stored memories
 It concludes with some output
 With the aid of technology, the
information processing model has found
impressive intellectual capabilities in
infants, like a basic grasp of cause and
effect by the middle of the first year
Affordances:
 Opportunities for perception and
interaction that are offered by a person,
place, or environment
 Which particular affordance is
perceived and acted upon depends on 4
factors:
 Sensory awareness
 Immediate motivation
 Current level of development
 Past experience
Selective perception:
 Example: consider a lemon, an
opportunity (an affordance) for
smelling, touching, tasting, viewing,
throwing, squeezing, and biting
 Further, each of these is an affordance
for pleasure, pain, or some other
emotional response
 Which affordance is perceived and acted
upon is dependent upon sensations,
motives, age, and experience
How do they research this?
 Mostly by looking at what infants attend
to on a TV screen
 Varies with age
 Varies with novelty
 Varies with experience
 Even varies with vocabulary
Visual Cliff experiment:
 Tested depth perception
 An infant’s awareness was affected by
experience, especially with falling
Movement: Dynamic Perception
 Dynamic perception is perception that is
primed to focus on movement and
change
 Babies pay close attention to things that
move and to people
 They also love to move: they grab, they
scoot, they crawl, they walk
 And they realize that motion changes
what the world affords them
Dynamic Perception:
 Almost any moving creature will get the
attention of an infant, who will chase and grab
at it
 Even infants who are not mobile will try to
catch a ball moving past them
 Experience affect this: younger babies may
ignore slow-moving balls, but attempt to catch
fast ones unsuccessfully, 20% or less success
 9-month-olds know to reach for the slow
moving balls, with an almost 100% success
rate
People Preference:
 Another universal principle of infant
perception is that they are innately
attracted to other humans, evident in
visual, auditory, tactile, and other
preferences
 In objects, infants prefer novelty
 In people, infants prefer familiarity
 They recognize their caregivers and
expect certain affordances from them:
comfort, food, entertainment)
More on people preference:
 Infants can infer emotional affordances
long before they understand language
 They “get” and respond to smiles,
shouts, facial expressions, and tones of
voice very early in life
 Studies indicate that 7-month-olds can
reliably match facial expression and
emotional tone of voice based on photos
and tapes
 And even younger infants can do this
with people they know
Smiling and mommy and daddy:
 In these experiments, infants did not
match the facial expressions and
emotional voice of strangers, but could
do so for their moms/dads, reacting
swiftly and correctly
 The idea of researchers is that parents
offer the affordance of JOY!
Memory:
 Processing and remembering requires a
certain amount of experience and brain
maturation
 Even with repetition, infants have difficulty
storing memories in their first year
 This is partly due to language deficits
 But infants do form memories--especially if
motivated and if reminded repeatedly
 Experiments with mobiles and kicking
indicate this
Reminders and Repetition:
 Reminder session: a perceptual
experience that is intended to help a
person recollect an idea, a thing, or an
experience, without testing whether the
person remembers it at the moment
 Research employing these sessions
demonstrated that even 3-month-olds
could remember actions that they
learned 2 weeks previously
And it gets better:
 After 6 months, infants can retain
information with less training, repetition
and reminding
 By the end of the first year, many kinds
of memory are apparent: deferred
imitation by 9 months
 By 18 months, infants can remember
and repeat complex sequences
 Toddlers action indicates conceptual
thinking is present
Child-directed speech:
 The high-pitched, simplified, and
repetitive way adults speak to infants
 Fosters early language development
 By 7 months, infants begin to recognize
words, but only words that are highly
distinctive: bottle, dog, and mama are
recognized before baby, Bobby, and
Barbie
 Within the first few months of life,
hearing becomes more selective, too
What selective hearing means:
 They prefer child-directed speech
 They like alliterative sounds
 They love songs--rhyme, rhythm, and
repetition
 And simple sounds more than complex
sounds
 Infants respond to sounds they like (by 4
months) with squealing, growling,
gurgling, grunting, crooning, and yelling
Babbling:
 The extended repetition of certain
syllables, such as ba-ba-ba, that begins
when babies are between 6 and 9
months old
 Responses from other people encourage
it
 It stops in deaf babies because they
cannot hear responses
 Using sign language shows that babies
can express language with gestures
sooner than with speech
First words:
 Usually at about 1 year
 Caregivers understand the baby’s words
before strangers
 In the first months of the second year of
life, vocabulary understanding is about
10 times the number of words they can
say
 Holophrases: a single word spoken in
such a way that expresses a complete,
meaningful thought
Naming Explosion:
 A sudden increase in an infant’s vocabulary,
especially in the number of nouns, that begins
at about 18 months of age
 In almost every language, the name of each
significant caregiver, sibling, and sometimes,
pet, is learned between 12-18 months of age
 Once the vocabulary reaches 50 words, it
builds at a rate of 50-100 words per month
 21 month olds say twice as many words as 18
month olds
Cultural differences:
 Cultures and families vary a lot in how
much child-directed speech children
hear
 Some are more verbal than others
 Some cultures emphasize quiet children
(not the US)
 And languages vary: some are VerbFriendly (verbs are placed before nouns)
so infants learn as many verbs as nouns,
unlike English
Social context matters, too
 If social interaction is emphasized by
the culture, verbs will be acquired as
much as nouns
 Example: Chinese toddlers learn more
verbs than US toddlers, who learn more
nouns
 Ethnicities that speak the language of
the country they have immigrated to
have babies that learn language like the
new culture
Concepts and Language:
 Some concepts are easy, some are not
 In English, infants confuse before and
after
 Dutch infants misuse out when it refers
to taking off clothing
 Learning adjectives is easier in Italian
and Spanish than in English or French
because of the patterns in those
languages
Language:
 Conveys/encodes cultural values and
social constructs
 If a child is more referential than
expressive, it likely reflects the cultures,
values, and priorities of the parents
Putting words together:
 Grammar: all the methods--word order, verb
forms, etc.--that languages use to
communicate meaning, apart from the words
themselves
 Grammar is obvious in 2-word sentences
(baby cry, more juice), at about 21 months
 Grammar will correlate with the size of the
child’s vocabulary, reflecting a knowledge of
clear communication
 Learning more than one language can slow
down language and grammar acquisition
Theories of Language Learning:
 50 years ago, the first theory reflected
behaviorism (learning theory) and said that
children needed to be taught language, step by
step, through reinforcement
 This theory includes the ideas that
parents/caregivers are expert teachers and help
children speak
 Frequent repetition is instructive
 Well-taught infants become well-spoken
children
Studies in Behavioral Theory:
 Indicate great variation in how parents
reinforce infants’ speech
 The frequency of paternal response at 9
months predicted infants language many
months later
 Adults teach, infants learn language
Theory 2: Infants teach
themselves
 Noam Chomsky & followers believe
that language is too complex to be
learned through step-by-step
conditioning
 Believe that because infants all master
basic grammar at about the same age,
there is a human mental structure that all
are born with that prepares them to
incorporate aspects of language
Language Acquisition Device:
 Chomsky’s term for a hypothesized
mental structure that enables humans to
learn language, including the basic
aspects of grammar, vocabulary, and
intonation
 Enables children worldwide to derive
the rules of grammar from the speech
they hear everyday (whether English,
Tamil, Urdu, Chinese, or Xhosa)
This theory is accepted by many:
 Reflects the differences without
ignoring language characteristics
 Reflects the fact that all languages are
logical, coherent and systematic
 Believes that the brain expects
language, and quickly and efficiently
connects neurons to support whatever
words an infant hears
 Works even with deaf infants who are
taught signs
Third Theory: Social impulses
foster infant language learning
 Social-Pragmatic theory: says that
neither behaviorism nor epigentic theory
is correct--says that communication, the
social reason for learning language, is
most important
 Infants communicate because they are
social beings dependent upon each other
for survival, well-being, and joy
Social newborn:
 Newborns seek out human faces
 By 9 months, infants’ brain patterns
indicate attention when they hear people
talk to them
 The emotional content, not the words,
are most important in early
communication
 Communication is the servant of social
interaction
Social toddler:
 Social impulses propel toddler language
acquisition
 Toddlers learn language much more
quickly from human interaction than
from television, even though they watch
TV
 Thus social language acquisition is more
meaningful than simply learning words
Hybrid theory:
 All three perspectives have merit
 Some of each theory has been
demonstrated to work
 The important thing is that children are
active learners, and that multiple factors
are involved in learning language
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