1. CHAPTER 3
PHYSICAL AND COGNITIVE
DEVELOPMENT IN INFANCY

2. THE BRAIN
• Contains tens of billions of nerve cells at birth
• Shaken baby syndrome - Brain swelling and
hemorrhaging
• Brain’s development
• Lateralization
3-2
Four Lobes

3. DENDRITIC SPREADING
3-3

4. SYNAPTIC DENSITY IN THE HUMAN BRAIN
FROM INFANCY TO ADULTHOOD
3-4

5. THE COMPETENT NEWBORN
Reflexes
[Surgery]

6. SENSORY CAPABILITIES OF THE
NEWBORN

7. HABITUATION/DEHABITUATION

8. HABITUATION/DEHABITUATION
What does habituation imply about memory processes of infants?

9. CEPHALOCAUDAL AND
PROXIMODISTAL PATTERNS
• Cephalocaudal
• Proximodistal
• Hierarchical integration

10. THE FIRST YEAR
• Average North American (full term) newborn ~ 20 inches
long; 7 pounds
• Lose ~5 to 7% of body weight adjusting to feeding. Back
to birth wt in 2 wks.
• Double birth weight by 5 months; nearly triple by 12
months

11. THE FIRST TWO YEARS
1 year: ~30 inches tall.
2 years: ~35 inches tall—
nearly half of their eventual
adult height

12. INTEGRATING THE BODILY SYSTEMS:
THE LIFE CYCLES OF INFANCY
Behavior becomes integrated through the
development of various body rhythms

13. SLEEP
• Considerable individual variation
• newborns can sleep 16 to 18 hours a day (average
~16)
• preferred patterns of sleep vary
• Infants spend a greater amount of time in REM
(rapid eye movement) sleep
• by 3 months of age, the percentage of time in REM
sleep decreases [next]

15. SIDS
• Children in U.S. = 1910 (2011)
• The leading cause of death in children under 1
year old (except for congenital abnormalities and
short gestation)
• Risk of SIDS is highest at 4 to 6 weeks of age
• Occurs in children of every race and
socioeconomic group
(Congenital abnormalities = 5013; Short gestation = 4106)

16. DECLINING RATES OF SIDS
SIDS Rate and Back Sleeping
(1988 – 2006)
1.4 1.39
1.3 1.3
1.2 1.17
1.03
0.87
0.77
55.7
0.74 0.72
64.4 66.6
0.67
0.62
72.2
75.7
71.6 71.1 72.8
70.1
0.56 0.57 0.53 0.56 0.54 0.55
17
13
26.9
38.6 35.3 53.1
1.5
1.0
0.5
0.0
19 88
19 89
19 90
19 91
19 92
19 93
19 94
19 95
19 96
19 97
19 98
19 99
20 00
20 01
20 02
20 03
20 04
20 05
20 06
AAP Recommendation Back to Sleep Campaign
Year
SIDS Rate
(Deaths Per 1,000 Live Births)
100
50
0
Percent Back Sleeping
SIDS Rate Source: CDC, National Center for Health Statistics,
Sleep Position Data: NICHD, National Infant Sleep Position Study.
U.S. rates have dropped dramatically as parents put babies “back to sleep.”

17. GROSS MOTOR SKILLS — LARGE
MUSCLE ACTIVITIES
• Move by themselves - 6
months
• Sit unsupported - 6
months.
• Crawling - 8-10 months
• Standing with support - 8
months
• Infants can walk holding
onto furniture by 9 months
and walk alone by ~1 year.

18. Physical Milestones
First Year
Eating:
• Can begin using a “sippy cup”
• Can be spoon fed
• Can be introduced to SMALL-SIZED solid foods
Small Motor Coordination:
• Can pick up toys in both hands (and bang them together!)
•Will practice dropping objects
• May throw objects (especially…everything)
•Will begin to pick up “Cheerios” or other small object with thumb
and index finger

19. FINE MOTOR SKILLS
• By 3 months infants
can coordinate
movements of
limbs.
• Infants can grasp an
object by 11
months.
• By age 2, infants
can drink from a cup
without spilling.

20. BENEFITS OF BREAST FEEDING
• Appropriate weight gain; lowered risk of childhood obesity
• Fewer allergies
• Reduction of diarrhea, respiratory infections, bacterial and
urinary tract infections
• Denser bones in childhood and adulthood
• Reduced childhood cancer and reduced incidence of breast
cancer in mothers
• Lower incidence of SIDS

21. Breast Feeding

22. Breast Feeding

23. Breast Feeding

24. INTRODUCING SOLID FOODS
• Most babies begin to eat solid foods b/t 4-6
months
• Foods are introduced gradually
• Weaning

25. DEVELOPMENT OF THE SENSES
Infants hear from the time they are born—
and even before

26. VISION
Infants show clear visual preferences that are present
at birth:
• Prefer to look at patterns and complex stimuli,
• Prefer to look at faces,
• Minutes after birth they show a preference for
certain colors, shapes, configurations.
Robert Fantz found
that 2- and 3-month-old
infants preferred
to look at more
complex stimuli.

27. VISION, CONT.
• Newborn infants cannot see beyond a distance of 20 feet
• By ~6 months, the average infant's vision is 20/20
• Gibson's "visual cliff" experiments indicates depth
perception

28. VISUAL PERCEPTION

29. HEARING, TOUCH, AND PAIN
• Prenatally at 7 months, infants can hear
sounds such as mother’s voice and music
• Immediately after birth, infants cannot hear
soft sounds or pitch as well as adults do
• Infants also display amazing resiliency
• Within several minutes after the circumcision
surgery (which is performed without
anesthesia), they can nurse and interact in a
normal manner with their mothers

30. SMELL AND TASTE
• Newborns can differentiate odors
• Sensitivity to taste might be present even before birth
• At only 2 hours of age, babies made different facial
expressions when they tasted sweet, sour, and bitter
solutions

31. COGNITIVE DEVELOPMENT IN
INFANCY
© 2006 Pearson Education/Prentice-Hall Publishing

32. Infant cognition develops through changes in the way
children approach problems (infants learn by doing).

33. ASSIMILATION AND ACCOMMODATION
• Processes of development
• Schemes:
• Behavioral scheme
• Mental scheme
• Assimilation: Using existing schemes to deal with new
information or experiences
• Accommodation: Adjusting schemes to fit new information
and experiences
Which one?
1. Infant uses sucking schema to suck on larger bottle/nipple after presentation of smaller
one.
2. One-year-old grabs every “round, rolly object” and tries to grab and throw; sees a beach
ball.

34. PIAGET
• Equilibration
• Individuals go through four
stages of development
• Cognition is qualitatively different
• Sensorimotor stage: Lasts from birth to about age 2.
• Infants construct an understanding of the world by coordinating
sensory experiences (such as seeing and hearing) with physical
actions
• Object permanence: Understanding that objects and
events continue to exist:
• When they cannot directly be seen, heard, or touched
3-34

35. SENSORIMOTOR STAGE
• Six substages
 Primary: reflexes determine interaction
• Accidentally sucks fist, feels good, so suck some more (provides
info about the world = cognitive development).
• Secondary: Begins to act on world (e.g., Rattles a rattle)
• Repeats actions; Goal-directed behavior; Develops object
permanence
• Tertiary circular reactions: deliberate variation of
actions
 Miniature “experiments” Hit drum, then table, then floor, then
head with a stick
• Beginning of thought ~18-24 months of age
• Mental representation

36. EVALUATING AND MODIFYING
PIAGET’S SENSORIMOTOR
STAGE
• Motor emphasized at the expense of sensory
-–largely ignores sensory and perceptual
abilities of infants
• Piaget's claim that certain processes are
crucial in stage transitions is not always
supported by the data
• Some researchers conclude that infants’
perceptual abilities are highly developed
very early in development
Criticism of Piaget

37. LANGUAGE DEVELOPMENT
• All human languages have
some common
characteristics
• Receptive/expressive
You talkin’ to me?!

38. KEY MILESTONES IN LANGUAGE
DEVELOPMENT
• Babies' sounds and gestures go through this
sequence during the first year
• Crying:
• Cooing:
• Babbling: [text is wrong]
• First Words ~ 10 to 14 months
• Average is 15 words by 15 months; First words are typically
holophrases (Holophrastic stage ~12-18 months)

39. LANGUAGE SOUNDS
• ~ 2-years-old, children can form noun-verb
sentences
• Overextension
• Underextension

40. A one-year-old
signing “sleep”

41. LEARNING THEORY/NATIVIST
APPROACHES
• Learning theory
• Chomsky > genetic;
innate mechanism
• All languages > similar
underlying structure
• LAD
• Interactionist view

42. INFANT-DIRECTED SPEECH (IDS)
[MOTHERESE]
 Use of this type of speech is related
to the early appearance of words

43. FIGURE 3.9 - MILESTONES IN GROSS
MOTOR DEVELOPMENT
3-43