1. PSYC 1120 Day 7 (Week #4) September 26, 2012

2. Agenda
Finish prenatal development

3. Three Trimesters
The germinal and embryonic periods occur in the first trimester
The fetal period begins toward the end of the first trimester and continues through the second and third trimesters
Viability (the chances of surviving outside the womb) occurs at the beginning of the third trimester.
Age of viability – about weeks on average

4. The Fetal Period
Fetal period begins two months after conception and lasts for seven months
Three months after conception-- fetus is about 3 inches long; weighs about 3 ounces
At birth, the average American baby weighs 7 ½ pounds and is about 20 inches long

5. Multiple Births Monozygotic - identical Dizygotic – fraternal
One ovum and one sperm
Splits early in the process of dividing
Must be the same sex
Dizygotic – fraternal
Several ova each fertilized
No more alike than other siblings
May be boys, girls or one (some ) of each
Increased incidence with fertility technology

6. Conjoined Twins Monozygotic twins who do not completely separate
Parts develop individually and other parts develop and grow together
Example: the Hensel twins from Minnesota

9. Teratogens Despite complexity, most babies are born healthy
Most hazards are avoidable
Teratology—study of birth defects
teratogens—broad range of substances that can cause environmental insults that may cause prenatal abnormalities or later learning abilities

10. Timing of Exposure
Critical period—in prenatal development, the time when a particular organ or other body part is most susceptible to teratogenic damage
entire embryonic period is critical

11. Amount of Exposure Dose and/or frequency
Threshold effect—teratogen relatively harmless until exposure reaches a certain level

12. Amount of Exposure, cont.
Interaction effect—risk of harm increases if exposure to teratogen occurs at the same time as exposure to another teratogen or risk

13. The Birth Process The Birth Process
first stage -- contractions cause the woman’s cervix to stretch and open
longest of the three stages
typically lasts 12 to 24 hours
second stage begins when the baby’s head starts to move through the cervix
45 minutes – 1 ½ hours, depending on number of pregnancies

14. third stage is afterbirth
placenta, umbilical cord, and other membranes are detached and expelled
shortest of the three birth stages

15. Where and Who? Where do births take place? Who assists?
In U.S., 99% take place in hospitals
Home births are far more common in many other countries
Who assists?
Obstetricians and nurses
Fathers or birth coaches
Midwives
Doula -- a caregiver who provides continuous physical, emotional, and educational support for the mother before, during, and after childbirth

16. Cesarean Delivery
Breech position – buttocks rather than head emerge first
Can prevent the baby from breathing normally
Cesarean delivery -- the baby is removed from the mother’s uterus through an incision made in her abdomen
May be lifesaving but carry the risks of major surgery

17. From Fetus to Newborn
Anoxia -- fetus or newborn has an insufficient supply of oxygen
Cause of brain damage
Immediately after birth, the umbilical cord is cut and the baby is on its own
Almost immediately after birth, a newborn is taken to be weighed, cleaned up, and tested

18. Apgar Scale
Used to assess the health of newborns at 1 and 5 minutes after birth
A score, or reading, of 0, 1, or 2 on each of these five health signs
heart rate, respiratory effort, muscle tone, body color, and reflex irritability
identifies high-risk infants who need resuscitation.

19. Apgar Scoring
Activity (muscle tone) 0 — Limp; no movement 1 — Some flexion of arms and legs 2 — Active motion
Pulse (heart rate) 0 — No heart rate 1 — Fewer than 100 beats per minute 2 — At least 100 beats per minute

20. Grimace (reflex response) 0 — No response to airways being suctioned 1 — Grimace during suctioning 2 — Grimace and pull away, cough, or sneeze during suctioning
Appearance (color) 0 — The baby's whole body is completely bluish-gray or pale 1 — Good color in body with bluish hands or feet 2 — Good color all over
Respiration (breathing) 0 — Not breathing 1 — Weak cry; may sound like whimpering, slow or irregular breathing 2 — Good, strong cry; normal rate and effort of breathing

21. Threats to Newborns Low birth weight Preterm Small-for-date
LBW -- less than 5 ½ pounds at birth
Very low birth weight - under 3 pounds
Extremely low birth weight - under 2 pounds.
Preterm
born three weeks or more before the pregnancy has reached its full term
Small-for-date
birth weight is below normal when the length of the pregnancy is considered

22. Amillia Taylor

23.
Amillia Sonja Taylor, born Oct. 24, 2006 after just under 22 weeks in the womb, will spend a few extra days in a Florida hospital as a precaution. Amillia, now a relatively robust 4½ pounds, was 9½ inches long and weighed 10 ounces at birth. (Baptist Hospital via The Miami Herald/AP Photo) (2007)

26. 2/21/2007

28. Amillia Taylor now weighs 17 pounds and measures 27 1/2 inches long
Amillia Taylor now weighs 17 pounds and measures 27 1/2 inches long. Her favorite foods are watermelon and bananas, and she has begun self-feeding and loves to laugh, play, and interact with her family members.
Despite the emotional ups and downs of the year since Amillia's birth, Taylor knows she would do it all over again if given a choice.

29.
October 2008
Amillia is also taking steps in their Homestead home and sounding out her few words and developmentally progressing very well.
26 pounds 26 ½ inches tall

30. Incidences and Causes of Low Birth Weight
Low birth weight and preterm births often occur together
Incidence of low birth weight varies considerably from country to country
Related to
Poverty
Maternal health status
Maternal nutrition

31. Consequences of Low Birth Weight
More health and developmental problems than normal-weight infants (Moss, 2006).
At school age, more likely to have a learning disability, attention deficit hyperactivity disorder, or breathing problems such as asthma (Wocadlo & Rieger, 2006).

32. Bonding
Bonding -- formation of a connection, especially a physical bond, between parents and the newborn in the period shortly after birth
Bonding is inhibited by
Anesthesia during labor
Hospital policies that separate mothers from infants

33. The Postpartum Period
Postpartum period -- lasts for about six weeks after childbirth or delivery or until the mother’s body has completed its adjustment and has returned to a nearly prepregnant state
Physical and psychological adjustments

34. Physical Adjustments
Fatigue can undermine the new mother’s sense of well-being and confidence in her ability to cope with a new baby
Dramatic changes in hormone production
Involution -- process by which the uterus returns to its pre-pregnant size

35. Emotional and Psychological Adjustments
Baby blues -- two to three days after birth, many women begin to feel depressed, anxious, and upset
Postpartum depression -- a major depressive episode about four weeks after delivery
strong feelings of sadness, anxiety, or despair that for at least a two-week period inhibit coping with daily tasks

36. The First Year of Life

37. Sensation versus Perception
Receiving environmental stimuli versus
Giving meaning to information received by the sensory system

38. Neuron
Parts of a neuron
dendrite
cell body
axon
synapse
myelin

39. A NEURON

42. The Brain
Left brain processes verbal, numerical, textual & logical information
Right brain processes spatial, colored & creative information

43. Hemispheres have differing functions but don’t work independently.
Both generally work together to perform most tasks.
One side may be faster.

45. The Brain Right and left halves are joined by the corpus callosum.
House calls it the Brooklyn Bridge connecting the two most important neighborhoods
Myelination

46. Myelin Sheath Insulation on axon to improve speed of transmission.
Also insulates axon from activity of other neurons.

48. http://videos. howstuffworks

49. Reflexes
Survival reflexes
Breathing
Sucking
Rooting
Swallowing

50. Other Reflexes
Startle or Moro
Babinski
Walking (stepping)
Swimming

51. Assignment
Finish Chapters 1 – 2
Begin Chapter 3