Human Development (ch 11 & lecture notes)
- 2 themes of human development, transition & c
ontinuity
- Development: sequence of age-related changes that occur as a person progresses from conception to death
- 4 lifespan periods:
1. Prenatal period: between conception and birth. Rapid.
- 3 phases:
- 1. Germinal stage: first 2weeks after conception. Zygote forms, cell implants in the uterine wall,
placenta begins to form.
- 2. Embryonic stage: 2 weeks to end of second month. Vital organs / bodily systems begin to
form = embryo. Beginning to look human, vulnerable stage.
- 3. Fetal stage: 2 months through birth. Rapid bodily growth, now called fetus. Between 22wks,
fetus reached age of viability: age at which baby can survive in event of a premature birth
- External environment can affect the fetus indirectly through the mother
- Teratogens: external agents such as drugs or viruses that can harm embryo or fetus.
Maternal Drug Use
- Tobacco, alcohol and recreational drugs are major concern, sedatives, narcotics and cocaine
particularly dangerous
- Fetal alcohol syndrome disorder (FASD): collection of congenital (inborn) problems associated
with excessive alcohol use during pregnancy. Affects approx 1 in 9 babies
Maternal Nutrition
- Fetus needs nutrients. Maternal malnutrition increases risk of birth complications /
neurological deficits.
Stress & Emotion
- Maternal emotions in relation to stressful events can have an impact on prenatal
development.
- Increased stillbirths, impared immune response, vulnerability to infectious disease…
Maternal Illness
- Many maternal illnesses can interfere w prenatal development. Such as measles, rubella,
syphilis and chickenpox.
Environmental Toxins
- Air pollution linked to impairments in cognitive development, slower mental / physical
development
Fetal Origins of Adult Disease
- Events during prenatal development can ‘program’ the fetal brain in ways that influence the
person’s vulnerability to various types of illness decades later.
2. Childhood: important transformations and progressions occur in childhood yrs.
Motor Development: progression of muscular coordination required for physical activities
↳ attributed to maturation: development that reflects the gradual unfolding of one’s genetic
blueprint.
Developmental Norms: median age at which individuals display various behaviours / abilities.
group averages.
Cultural Variations
- Connection between experience and maturation in motor development
- Rapid motor development observed in some cultures that provide special practice in basic
motor skills
, Differences in Temperament
- Temperament: characteristic mood, activity level and emotional reactivity
- Longitudinal design: observe one group of participants repeatedly over a period of time.
- Cross-sectional design: compare groups of participants of differing age at a single point in
time.
↳ cohort effects: occur when differences between age groups are due to the groups
growing up in different time periods.
- Alexander Thomas & Stella Chess conducted a longitudinal study of the development of
temperament.
- Temperamental individuality is well established by the time the infant is 2-3 months
old
- 3 basic styles of temperament:
- Easy children: (40%) happy, regular sleeping, adaptable
- Slow-to-warm-up children: (15%) less cheery, slower to adapting
- Difficult children: (10%) glum, erratic sleeping/eating, resistant to change
- 35% mix of 3
- Temperament highly influenced through heredity. Not unchangeable.
Early Emotional Development: Attachment
- Social world is key to development
- Attachment: close, emotional bonds of affection that develop between infants and their
caregiver
- Develop attachment to mother at 6-8 months
- Separation anxiety: emotional distress seen in many infants when they are separated from ppl
with whom they have formed an attachment. Peaks at 14-18 months
Theories of Attachment
- Harry Harlow’s study of attachment in monkeys
- Monkeys given 2 types of artificial mothers one of cloth, one of wire. Half of them fed
by wire other half by cloth. When monkeys frightened, all went to cloth mother even if
fed by wire.
- John Bowlby argued there must be a biological basis for attachment. Survival value.
- Mary Salter Ainsworth suggests attachment emerges out of a complex interplay between
infant and mother.
- Used method strange situation procedure where infants are exposed to a series of 8
separation and reunion episodes to assess quality of their attachment
- Secure attachment: child tends to be playful, less inhibited, exploration oriented,
sociable
- Avoidant attachment: child tends to maintain proximity while avoiding close contact w
stranger.
- Anxious-ambivalent attachment: child tends to engage in visual checking; signalling
to re-establish contact, callig, pleading; moving to re-establish contact, clinging
Day-Care and Attachment
- No harmful effect on children’s attachment relationship
Culture and Attachment
- U.S. - 67% secure, 21% avoidant, 12% anxious-ambivalent
↳ slightly different results for Germany & Japan
Personality Development
- Sigmund Freud believed foundation of personality is firmly laid down by age 5.