Chapter 3- The First Two Years
Body and Brain
Overview: 0-2
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Amazing Growth
Developing Motor and Sensory Skills
Health: Immunization, Safety, Nutrition
Learning about the World
Learning to Talk
Body Changes
Height and Weight
• Average weight at birth: 7.5 pounds
• Average length: 20 inches
• These numbers are norms, an average
measurement.
Early Brain Development
• Most critical biosocial aspect of growth
– newborn’s skull disproportionately large
– at birth, 25% of adult brain weight
– by age 2, 75% of adult brain weight
• Head measurement increases 35% in first
year
– brain development: changes in the brain’s
communication system
– Myelination speeds neural impulses about 10
times
Head Proportion
Body Changes
Body Changes
Well-baby checkup
• Doctor or nurse measures baby’s growth:
height, weight, and head circumference.
• Abnormal growth may indicate physical or
psychological problems.
• Headsparing- A biological mechanism that
protects the brain when malnutrition disrupts
body growth. The brain is the last part of the
body to be damaged by malnutrition.
Body Changes
• Neurons and synapses proliferate (increase rapidly in
number) before birth. This increase continues at a
fast pace after birth (exuberance), but soon an
opposite phenomenon occurs: the elimination, or
pruning, of unnecessary connections.
• The last part of the brain to mature is the prefrontal
cortex, the area for anticipation, planning, and
impulse control.
• Shaken baby syndrome- a life-threatening injury that
occurs when an infant is forcefully shaken back and
forth, a motion that ruptures blood vessels in the brain
and breaks neural connections.
Body Changes
• Newborns sleep about 17 hours a day, in one- to
three-hour segments.
• Newborns’ sleep is primarily active sleep: often
dozing, able to awaken if someone rouses them,
but also able to go back to sleep quickly if they
wake up, cry, and are comforted.
• Quiet sleep: slow brain waves and slow breathing
• Newborns have a high proportion of REM (rapid
eye movement) sleep, with flickering eyes and
rapid brain waves.
Moving and Perceiving
Motor Skills
• The first movements are not skills but
reflexes, involuntary responses to a
particular stimulus.
Moving and Perceiving
Some reflexes help insure survival: breathing, thrashing,
shivering, sucking, rooting, swallowing, spitting up.
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Other reflexes are signs of normal functioning:
Babinski reflex. When infants’ feet are stroked, their toes fan
upward.
Stepping reflex. When infants are held upright with their feet
touching a flat surface, they move their legs as if to walk.
Swimming reflex. When they are laid horizontally on their
stomachs, infants stretch out their arms and legs.
Palmar grasping reflex. When something touches infants’ palms,
they grip it tightly.
Moro reflex. When someone startles them, perhaps by banging on
the table they are lying on, infants fling their arms outward and then
bring them together on their chests, as if to hold on to something,
while crying with wide-open eyes.
Moving and Perceiving
• Gross motor skills- Physical abilities
involving large body movements, such as
walking and jumping.
• Fine motor skills- Physical abilities
involving small body movements,
especially of the hands and fingers, such
as drawing and picking up a coin.
Gross Motor Skills
• Involve large muscles and body movements
– Hold up torso/head about 4 mos
– crawl, creep, walk
– Locomotion increases risk of injury (falls/bumps
and getting into household chemicals and
equipment)-
Fine Motor Skills
• Small, finely tuned movements, especially of
hands and fingers, including
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successful swiping
adjusting reach
fingering, pointing, and holding
picking up (palmar 2-6 mos; pincer 12+ mos)
grasping a moving object
transferring objects from hand to hand
Moving and Perceiving
Moving and Perceiving
The sense of hearing develops during the
last trimester of pregnancy and is already
quite acute at birth; it is the most advanced of
the newborn’s senses.
Vision is the least mature sense at birth.
– Newborns focus only on objects between 4 and
30 inches away.
– Binocular vision, the ability to coordinate the two
eyes to see one image, appears at 3 months.
– Sensation is essential for the visual cortex to
develop normally.
Tasting, Smelling, and Touching
• taste—functions at birth; calmed by sugar,
sensitive to sour
• touch—comforted by human touch; feel pain
• smell—can distinguish between odors and
have preferences
• Early sensation is organized for
– social interaction
– comfort
Surviving in Good Health
Preventing Sudden Infant Death Syndrome
• In 1990, about 5,000 babies died of sudden
infant death syndrome (SIDS) in the United
States.
• The actual cause of SIDS is still unknown: low
birthweight, heavy clothing, soft bedding,
teenage parenthood, and, particularly, maternal
smoking are risk factors.
• Putting infants to sleep on their backs reduces
the risk but does not eliminate it.
Surviving in Good Health
Adequate Nutrition
• For every infant disease (including SIDS),
breast-feeding reduces risk and malnutrition
increases it, stunting growth of body and
brain.
• Breastfed babies are less likely to develop
allergies, asthma, obesity, and heart disease.
• As the infant gets older, the composition of
breast milk adjusts to the baby’s changing
nutritional needs.
Nutrition: Breast Is Best
• Breast Milk
- begins with colostrum, high-calorie nourishment before
milk “lets down”
- easily digestible
- has antibodies and antibacterial properties
- better for baby’s health
• Bottle Feeding
- better option if mother is HIV-positive or using drugs
- Babies more likely to have allergies
• Feed on demand
Why “Breast is Best”
• The nutritional composition of breast milk
is ideal for human infants.
• As the baby grows and its nutritional
needs change, mother’s milk adapts to
meet these needs.
• Breast milk is easily digested.
• Breastfeeding promotes attachment (close
nurturing bond).
Why “Breast is Best”
• Breastfeeding reduces the incidence &
severity of diseases, infections some
chronic diseases.
• Breastfeeding enhances brain
development.
• Breastfeeding helps reduce the possibility
of SIDS.
Why “Breast is Best”
• Breastfeeding reduces postpartum
bleeding and aids involution (uterus
returning to normal size).
• Breastfeeding the risk of breast cancer &
ovarian cancer for the mother.
• Breastfeeding mothers have fewer hip
fractures in the postmenopausal period
than women who have never breastfed.
Infant Cognition
Piaget
• sensorimotor intelligence
– Piaget’s term for the way infants think—by using their senses
and motor skills—during the first period of cognitive
development.
• assimilation
– Piaget’s term for a type of adaptation in which new experiences
are interpreted to fit into, or assimilate with, old ideas.
• accommodation
– Piaget’s term for a type of adaptation in which old ideas are
restructured to include, or accommodate, new experiences.
• object permanence
– The realization that objects (including people) still exist when
they can no longer be seen, touched, or hear. (8 months)
Infant Cognition
Infant Cognition
Information-processing Theory
• A perspective modeled on computer
functioning.
• Information-processing theorists believe that
a step-by-step description of the mechanisms
of thought adds insight to our understanding
of cognition at every age.
• Information-processing research has
overturned some of Piaget’s conclusions—
including the concept of object permanence.
Infant Cognition
• The visual cliff was designed to provide
the illusion of a sudden dropoff between
one horizontal surface and another.
• Mothers were able to urge their 6-montholds to wiggle forward over the supposed
edge of the cliff, but 10-month-olds
fearfully refused to budge.
Infant Cognition
Early Memory
• According to classic developmental theory,
infants store no memories in their first year.
• Developmentalists now agree that very young
infants can remember if the following
conditions are met:
– Experimental conditions are similar to real life.
– Motivation is high.
– Special measures aid memory retrieval.
Language Learning
Early Communication
• Child-directed speech- The high-pitched,
simplified, and repetitive way adults speak to
infants. (Also called baby talk or
motherese.)
• Babbling- The extended repetition of certain
syllables, such as ba-ba-ba, that begins when
babies are between 6 and 9 months old.
• Naming explosion- A sudden increase in an
infant’s vocabulary, especially in the number
of nouns, that begins at about 18 months of
age.
Language Learning
First Words
• At about 1 year, babies speak a few words. First
words (2 new/week); common in US: ball,
dadddy, book, go, no, up
• Spoken vocabulary increases gradually (about
one or two new words a week).
• Once spoken vocabulary reaches about 50
words, it builds quickly, at a rate of 50 to 100
words per month.
Language Learning
• Holophrase- A single word that is used to
express a complete, meaningful thought. All new
talkers say names and utter holophrases.
• Infants differ in their use of various parts of
speech, depending on the language they are
learning, e.g. more nouns and fewer verbs.
• Naming explosion - sudden increase in infant
vocabulary, especially nouns, beginning at 18
months (9/day)
• Pivot words used in 1st 2 word phrases (no up,
no cup)
Language Learning
Acquiring Grammar
• Grammar includes all the devices by
which words communicate meaning:
sequence, prefixes, suffixes, intonation,
loudness, verb forms, pronouns,
negations, prepositions, and articles.
• Worldwide, people who are not yet 2 years
old already use language well.
Language Learning Theories
Learning Approach: Infants need to be taught
• B. F. Skinner (1957) noticed that spontaneous
babbling is usually reinforced.
• Parents are expert teachers, and other caregivers
help them teach children to speak (high pitch,
simple vocab., short sentences, repetition, more
questions & commands)
• Frequent repetition of words is instructive,
especially when the words are linked to the
pleasures of daily life.
• Well-taught infants become well-spoken children.
Language Learning Theories
Language Learning is Innate
• Language acquisition device (LAD)Chomsky’s term for a hypothesized mental
structure that enables humans to learn
language, including the basic aspects of
grammar, vocabulary, and intonation.
Language Learning Theories
Social Impulse Toward Communication
• Infants communicate in every way they
can because humans are social beings,
dependent on one another for survival,
well-being, and joy.
• Infants seek to respond by vocalizing,
babbling, gesturing, listening, & pointing
Why Sign?
• Deaf children (whose parents sign to
them) produce first words before hearing
children
• Gross motor movements develop before
fine motor skills
• Signing takes advantage of natural
gestures (wave, clap)
Why Sign? (2)
(Research on using signs with young children)
• Enhances
communication
(Lindert, 2001)
• Linguistically &
cognitively advanced
at age 4 (Goodwyn,
Acredolo & Brown,
2000)
• Less frustration &
aggressive behavior
(Grabmeier, 1999)
• Enhanced
vocabulary, spelling
and reading skills
(Daniels, 2001)
Why Sign? (3)
(Effects of signing on school-aged children)
• Children’s ability to integrate language
with gestures is positively related to their
literacy skills (Anthony, 2002).
• Advanced phonemic & metalinguistic
awareness (Anthony & Lindert, in press)
• Average IQ advantage of 12 points
(Acredolo & Goodwyn, 2000)
Avoid Tantrums
Tantrums occur…
• Out of frustration
• When child is unable
to communicate
needs/desires
Signing allows…
• Communication
before speech
• Manners
• A way to halt bad
behavior
• Silent or private
communication