Infancy and childhood

Infancy and Childhood

Nature vs Nurture

  1. How much nature ( genetics) and how much nurture (environment) contribute to a person’s biological , emotional, cognitive, personal, and social development?

Developmental Psychologist

  1. Studies the emotional, cognitive, personal, and social development across the life span, from infancy through late adulthood.

Prenatal period

  1. Extends from conception to birth and lasts about 266 days  ( 9 months +/_). Consists of 3 successive phases, germinal, embryonic, and fetal.
  2. Prenatal period a single cell will divide and grow to form 200 billion cells.

Germinal Stage

  1. First stage of prenatal development and refers to the two- week period following conception

Embryonic Stage

  1. Second stage, has a span from 2-8 weeks following conception, during this stage cells divide and begin to differentiate into bone, muscle and body organs
  2. After 21 days since conception, the beginnings of a spinal cord, and eyes appear.
  3. After 24 days, cells differentiate to form what will become the heart
  4. After 28 days, tiny buds develop into arms and legs
  5. After 42 days features of the face begin to take shape
  6. During this phase the embryo is very fragile, since all basic organs are being shaped. This is the time when most miscarriages occur.
  7. Toward the end of this stage the organism has a number of body organs as well as a functioning heart.
  8. The embryo measures about 4 cm long.
  9. During this Second Stage the embryo is most vulnerable to toxic agents and chemicals. To help filter some of this out the body developed the Placenta ( organ that connects the blood supply of the mother to that of the fetus. It acts like a filter allowing oxygen and nutrients to pass through while keeping out some toxic or harmful substances).
  10. However, certain drugs like nicotine, caffeine, marijuana, cocaine and heroin , along with other OTC and prescription medications can easily pass through  and into the fetuses blood vessels.
  11. It has been found that HIV although sometimes can be passed from Mother to child, is usually stopped  through prenatal testing early on in pregnancy.
  12. If a mother is HIV + then medications ( such as antivirals) are used after 28 weeks, to stop transmit ion. Those treated have a less than 5 % chance of transmitting the virus. 25% if not treated.

Fetal Stage

  1. Begins two months after conception and lasts until birth
  2. End of fetal stage , usually around 38-42 weeks after conception
  3. Development of vital organs such as lungs , as well as physical characteristics.
  4. Infants born under 6 months will have great difficulty due to the lack of development of their lungs. Any infant born under 24-28 weeks, has a mortality rate of 5 %.

What Happends?

  1. Week 4: Cramping, PMS symptoms, Acne, and a positive pregnancy test
    1. Baby: Burrowing of egg into uterine wall
  2. Week 6 : Bloating, queasiness, Frequent urination
    1. Baby: Size of a pea, Folds are forming to make all facial features, organs, and appendages
  3. Week 8: Uterus growth to the size of an orange, morning sickness begins
    1. Baby: Heartbeat Begins, rate is 150 beats per minute
  4. Week 10: Slight roundness to your lower tummy. Nausea and Vomiting, Increase in veins.
    1. Baby: Bones and cartilage are forming, indentations for knees and elbows begin, tooth buds begin to form. Testosterone, and estrogen ( depending on Boy or Girl are surging)
  5. Week 12: Uterus growth  is the size of a grapefruit, Frequent urination, Breast Tenderness, food aversions, dizziness.          
    1. Large as a plum, digestive system is practicing. Bone marrow beginning
  6. Week 14:Begin to show higher in abdomen, Uterus rises out of pelvis and towards front of body, can feel uterus is presses on Tummy
    1. Baby: Moving around constantly, More ballet like.
  7. Week 16: Tummy says “ baby” and not “ fat”, uterus is 3 inches below belly button
    1. Baby: Bones begin to form in ear ( mothers voice can be heard), eyebrows and eyelashes have formed
  8. Week 18: Start to feel “ gas bubbles” as baby begins to move more so you can feel him/her. Joints begin loosening for delivery.
    1. Baby weighs as much as a piece of chicken, Can feel all twists, rolls, jabs etc.…
  9. Week20: Midpoint of pregnancy! Is it a Girl or a Boy? Hair and Nails grow and thicken
    1. Baby: Size of a small cantaloupe, Girl: Vagina is forming as well as ovaries, Boy: testacies have started to descend
  10. Week 22: Uterus is 1 inch above belly button. Edema ( swelling of the feet, hands and face due to water retention)  can occur.
    1. Baby: weight 1 lb. Grip is developing, can perceive light and dark
  11. Week 24: Carpel Tunnel syndrome, hip and back pain
    1. Baby:  weighs 1 and ½ lbs., face mostly formed, can gear loud noises
  12. Week 26: Belly timer going off? Cloths no longer fit.
    1. Baby: Eyes open for first time, retina is developed,Sence of touch is heightened.
  13. Week28: Baby kicking all the time.
    1. Baby: Baby might be dreaming about you. REM begins. Weighs 2 and ½ lbs., could be born and survive with care.
  14. Week 30: Frequent urination is back, food aversions are back, lack of sleep is back. Breasts gear up for lactation. Heartburn at its strongest
    1. Baby:  Weight hasn’t changed much, however the baby's brain is forming more, creating ridges and valleys to what was once smooth. Bone marrow has taken over production of red blood cells.
  15. Week 32: Braxton hicks, the practice of contractions for delivery
    1. Baby: Weight 4 lbs., cramped quarters begin, limiting movement to jabs and punches. Head down position started, Sleep cycles are for 20-40 min at a time.
  16. Week 34: Uterus is still growing, about 5 inches above the belly button. Vision is sometimes less sharp.
    1. Baby: Could be as tall as 20 inches, weighs close to 5 lbs. Fingernail growth has reached the edge of the finger.
  17. Week 36: Last month of pregnancy! The pregnant waddle begins
    1. Baby: Bones  in body and head are formed, but soft as to fit in birth canal, Skull bones are not fused as to allow the head to pass during birth, weight 6 lbs.
  18. Week 38: Baby drops into pelvice for birth, breasts could leak
    1. Baby: All organs mature more, including lungs.
  19. Week 40: Delivery Time!

Gentic Development

  1. Brain Growth: genetic programing regulates how the brain develops, making thousands of connections between neurons. During the first 3 months of life, the newborns brain is the most active.


  1. Faces:  Show a preference for their mother’s face over strangers in the first dew days after birth. Newborns first learn to recognize a persons eyes.
  2. Hearing:  Very keen hearing, by 6 months they are able to make out sounds that are necessary for learning language
  3. Touch:  Highly developed. When their cheeks are slightly touched their heads will turn.
  4. Smell and taste: at 1 day old a newborn could distinguish between a citrus smell and a floral odor. Can also determine sweet and salty, and dislike bitter flavors.
  5. Depth Perception: Age of 6 months  they have depth perception. This was demist rated by a visual cliff.

Visual Cliff

  1. Glass tabletop with a checkerboard pattern over part of its surface ; remaining surface consists of clear glass with a checkerboard pattern several feet below, creating the illusion of a clifflike drop to the floor.

Motor Development

  1. The stages of motor skills that all infants pass as they acquire the muscular control necessary for making coordinated movements.
  2. Proximodistal Principle: parts closer to the center of the infants body develop before parts farther away.
    1. I.E. Infants can roll over before they can walk or crawl
  3. Cephalocaudal Principle: parts close to the head develop before parts close to the feet
    1. I.E. Infants can life their head and sit up before can control their legs
  4. Maturation: Changes that are genetically or biologically programmed rather than acquired through learning or life experiences
    1. I.E. If children are able to develop their reflexes earlier in life, they are more likely to walk earlier than children who didn’t.
  5. Developmental Norms: Average age that a child performs various kinds of skills or exhibit abilities or behaviors
    1. I.E. By age 2 a child can grasp a cup, walk up and down he stairs, operate toys and get into a lot of trouble.

Emotional Development

  1. Temperament and Emotions:
    1. Easy babies: make up 40 %, are happy, cheerful and have regular eating and sleeping patterns
    2. Slow – to – warm- up babies: make up 15%, are moody, and tend to take longer to adapt to new situations
    3. Difficult babies: make up 10 %, fussy, fearful, and more intense in their reactions. Have more serious emotional problems.
    4. No- Single- Category babies: make up 35%, variety of above traits, and cannot be classified into those mentioned above.


  1. Theory: babies form an attachment to their parents through a gradual process that begins shortly after birth and contributes through early childhood.
  2. At 4-6 weeks old a child will begin social smiling, which will elicit joy and pleasure in the parents. At 6 months the child infant will greet the parents with happy smiles.
  3. Separation Anxiety: infants distress as indicated by loud protests, crying, and agitation whenever the infants parents temporarily leave.

2 types

  1. Secure: infants who use their parents or caregiver as a safe home base from which they can wander off and explore their environment
  2. Insecure: infants who avoid or show ambivalence or resistance toward their parent or caregiver

Social Development

  1. How a person develops a sense of self or a self identity, devolves relationships with others, and develops the kinds of social skills important in personal interactions.

Freud and Erickson

  1. Oral Stage, Anal Stage, Phallic Stage, latency Stage, and Genital Stage
  2. Eric Erickson's psychosocial stages:  8 developmental periods during which an individuals primary goal is to satisfy desires associated with social needs.
    1. Shown on next page




Potential Strength to be gained


0 to 1

Basic Trust vs. mistrust


The infant must form a first , loving, trusting relationship with the caregiver or risk a persisting sense of mistrust

2 to 3

Autonomy vs. shame and doubt


The child's energies are directed toward the development of key physical skills, including walking and grasping and sphincter control. The child learns control but may develop shame if not handled properly.

4 to 5

Initiative versus guilt


The child continues to become more assertive, to take more initiative but may be too forceful and injure others or objects , which leads to guilt.

6 to 12

Industry vs. inferiority


The school- aged child must deal with the demands to learn new, complex skills or risk a sense of inferiority.

13 to 18

Identity vs. role confusion


The teenager ( or young adult) must achieve a sense of identity both who he /she is and what he/she will be in several areas, including occupation, gender role, politics, and religion.

19 to 25

Intimacy vs. isolation


The young adult must risk the immersion of self in a sense of "we". Creating one or more truly intimate relationships, or suffer feelings of isolation

25 to 65

Generativity vs. self- absorption and stagnation


In early and middle adulthood, each adult must find some way to satisfy the need to be generative , to support he next generation or turn outward from the self towards others

65 +

Ego integrity vs. despair


If all previous stages have been dealt with reasonably well, the culmination is an acceptance of one self as one is.