Lecture 2 Flashcards
What is nature?
Biology/Heredity/Maturation
What is nurture?
Environment (e.g., Locke -> tabula rasa)
What is nature specifically relating to?
Maturation - Natural growth that unfolds in a fixed sequence independently of the environment
Who spoke of this?
Gesell
What spoke about nurture?
Watson
What is nurture specifically related to?
Behaviour - that is all learned
What is the current contemporary approach?
The current argument in developmental psychology is that heredity (biology) creates predispositions that interact with environmental influences (family, friends, teachers, media, random events).
What is the percentage that comes from genes and environment?
It cannot be ascertained how much nurture contributes and much environmental contributes
Why is the percentage argument difficult?
- Need to differentiate simple VS complex characteristics (height vs intelligence)
- Reciprocal interaction between nature and nurture -> heredity and environment are correlated, e.g., intelligence
- Children are “niche pickers” -> they actively choose environments that bets suit their genetic predispositions
What happens in prenatal development?
Process of development begins when sperm fertilizers an ovum (or egg cell) - A new cell nucleus is created from the genetic material provided by male and female
What is a zygote?
One celled organism, produced by union of sperm and an ovum
What are the stages of prenatal development?
There are three stages of prenatal development;
Germinal stage
Embryonic stage
Foetal stage
When is the germinal stage?
Fertiliziation to two weeks gestation
Once the zygote begins to divide 24-36 hours after fertilisation, it travels down the fallopian tubes to the uterus
A blastocyst is formed (150 cells), attaches to the walls of the uterus and is fully embedded in the wall of the uterus.
What happens in the embryonic stage?
Two weeks gestation to two months gestation (i.e., week 3 to week 8 after conception)
Rapid development of major organs (e.g., heart, nervous system, stomach, sex organs).
What stage does the placenta begin?
The Embryonic Stage
What does the placenta do?
Transports nutrients from mother to foetus
Carries wastes from foetus to mother
Screens out potentially harmful substances, especially bacteria
By the end of the embryonic stage, what happens to the embryo?
Measures 2.5cm in length
Develops eyes, ears, nose, jaw, mouth, lips, arms, hands, fingers, legs, feet, toes
When is the foetal stage?
Two months gestation to nine months gestation
What happens in the foetal stage?
Around six months gestation (i.e., from approx. week 24 or 25 after conception)
Eyelids open
Foetus can breathe regularly for 24 hour length periods
Viable (but not guaranteed) of surviving outside the womb
Eight months gestation (i.e., from approx. week 32 or 33 after conception):
Responds to light and touch
Learning occurs - habituation
What are some of the factors that affect prenatal development
The timing and stages of prenatal development are:
Biologically determined, but also affected by the environment in the womb (i.e., the environment)
Effects of teratogens especially important
What are teratogens?
External substances that can penetrate the placenta, resulting in spontaneous abortion or birth defects
Most likely to affect development when ingested during the period of rapid organ development and differentiation, known as the critical period
What are some examples of teratogens?
Bacteria and protozoa (raw meat/fish, cat feces) with effects such as blindness, deafness, intellectual disabilities
Virus (Rubella etc., examples blindness, deafness, intellectual disabilities, heart defects, cerebral palsy)
Cytomegalovirus (CMV) flu like symptoms, Herpes Simplex (C-section is recommended)
HIV/AIDS
Maternal drug use:
Increases mothers risk of miscarriage, still birth and prematurity, increases risk for SIDS and contributes to slower than average cognitive development, attention deficits, hyperactivity, conduct problems
Maternal drug use (Alcohol) Foetal Alcohol Spectrum Disorders - collection of congenital (inborn) problems, etc.
What are some other examples of teratogens?
Maternal nutrition
Environmental toxins and hazards
Emotional stress
Discuss newborn physical development, what are the two factors?
The physical body grows rapidly from birth throughout infancy;
Weight: 3kg at birth, infants weight doubles by 4 months, gradual weight increase to 2 years as bones and muscles grow.
Length: Babies gain 2.5cm per month for each of the first 12 months