The First Two Years: Biosocial Development

1
The First Two Years Biosocial Development
The Developing Person Through Childhood and
Adolescence by Kathleen Stassen Berger
Seventh Edition
Chapter 5

• Slides prepared by Kate Byerwalter, Ph.D., Grand
  Rapids Community College

2
Body Changes

• An average newborn is 7½ lbs, 20 inches.
• Infants triple their birthweight by 1 year.
• By age two, they are about ½ their adult height
  (!) and ¼ their adult weight.

3
Body Changes
ALL INES YVETTE LARAYA ERESE
4
Body Changes (cont.)

• Percentile ranks allow comparisons of an
  individual infant to group norms
• A sudden drop in percentile rank might indicate a
  developmental problem.
• Head Sparing in cases of inadequate nutrition,
  the brain keeps growing

5
The Wonderful World of SLEEP

• Newborns sleep 17 hours a day.

DAVID YOUNG-WOLFF / PHOTOEDIT, INC.
6
Infant Sleep (cont.)

• Infants gradually adjust to the familys sleep
  schedule.
• 80 of 1 year olds sleep through the night
• Sleep cycles are influenced by brain maturation,
  diet, child-rearing practices, and birth order

7
Make It Real Co-Sleeping

• Some families practice co-sleeping, in which
  the family shares a bed.
• Why might a family do this? Do you think it could
  benefit or harm an infant?

8
Research on Co-Sleeping

• CULTURE influences the decision (it is more
  common in Eastern culture)
• It is not harmful to an infant, under normal
  circumstances (e.g., if adult is not drunk)
• It may increase dependence on parents

9
Brain Development

• Brain development during infancy is fascinating
  and rapid.
• By the age of 2, the brain is 75 its adult
  weight
• Neural connections in the brain also develop

10
(No Transcript)
11
Brain Development (cont.)

• Regional specialization neurons in certain areas
  of the brain correspond to different tasks
• Examples language, vision, smell, emotional
  processing, recognizing faces vs. objects, etc.

12
The Developing Cortex
13
Brain Development (cont.)

• Transient exuberance rapid proliferation of new
  neural connections in infancy
• As many as 15,000 new connections per neuron and
  100 trillion synapses by age 2!
• Pruning makes the brain more efficient by
  eliminating underused connections.

14
(No Transcript)
15
What influences early brain development?

• Brain development is influenced by maturation and
  experiences.
• Experience-expectant brain functions require
  basic common experiences.
• Example No matter where an infant lives, he or
  she hears sounds and language.

16
What influences early brain development? (cont.)

• Experience-dependent brain functions depend on
  exposure to particular events.
• Example The particular sounds and language heard
  (and learned) varies across infants.
• Example The development of impulse control
  depends on both maturation and practice.

17
Why are neural connections so important?

• A certain level of neural connections indicate
  healthy brain development.
• Lack of connections may result from child abuse
  or neglect early in life, and can have lasting
  consequences.
• Example Infants in orphanages

18
Make it Real Activities

• Make a list of toys and activities that can
  stimulate healthy brain development in the first
  two years of life.

PHOTODISC
19
Implications for Caregivers

• Is it possible to overstimulate an infant? YES!
• The key is to follow the infants lead
• Self-righting an infants inborn drive to use
  whatever experiences available to develop the
  brain (wow!)

20
Infant Senses

• All five senses function at birth
• Vision, hearing, taste, touch, smell
• Perception (the brains processing of the
  sensation) develops over time.

21
Infant Senses (cont.)

• Hearing is well developed at birth
• Infants respond to sudden noises, human voice,
  phonemes of language
• Vision is the least mature sense at birth
• Bionocular vision develops around 14 weeks
• Adult vision (20/20) by one year

22
Infant Senses (cont.)

• Taste, touch, smell function well at birth

All CINDY CHARLES / PHOTOEDIT, INC.
23
Motor Skills

• Motor skills develop according to two principles
• Cephalocaudal growth proceeds from head-to-toe
  (e.g., head lift before sit, stand, walk)
• Proximal-distal growth proceeds from torso
  outward (e.g., sucking before kicking)

24
Motor Skills (cont.)

• Reflexes account for the first motor skills.
• Survival reflexes include sucking, breathing,
  body temperature.
• Other reflexes include the Babinski, Moro, and
  stepping reflexes.

25
Infant Reflexes
ASTIER / BSIP / SCIENCE SOURCE / PHOTO
RESEARCHERS, INC.
JENNY WOODCOCK REFLECTIONS PHOTOLIBRARY / CORBIS
PETIT FORMAT / PHOTO RESEARCHERS, INC.
26
Make it Real Motor Skills

• At what age do you think most infants learn to
  walk?
• What about you?

PHOTODISC
27
(No Transcript)
28
Motor Skills (cont.)

• Gross motor skills involve large muscle
  movements.
• Examples crawling, sitting, walking
• Walking typically occurs around 12 months, with
  great variability across infants.
• Walking requires muscle strength, brain
  maturation, and practice.

29
Motor Skills (cont.)

• Fine motor skills involve small muscle movements.
• Examples learning to grasp, shake, pull an
  object, hold a spoon, write, draw, etc.
• Motor skills are influenced by genes, culture,
  and patterns of infant care.

30
Public Health Measures

• Infant survival rates have increased
  significantly in the past century, due to better
  nutrition, cleaner water, and immunization.
• Although not without controversy, immunization
  has been hailed as a major achievement (e.g.,
  significantly reducing polio, small pox, measles).

31
(No Transcript)
32
Sudden Infant Death Syndrome

• SIDS is infant death of an unknown cause.
• Protective factors (although not a guarantee)
  include NO cigarette smoke in house, noise and
  touch during sleep, breast feeding, sleeping on
  back