Human Development
This chapter covers physical, cognitive, psychosexual, and social development over the life span.
There major issues in developmental psychology
1. Nature vs. Nurture: How much genetic inheritance (Nature) or experience (Nurture) influences our
development?
2. Stages vs. Continuity: Is development a sequence of separate stages (Stages) or a continuous, gradual
process?
3. Stability vs. Change: Do our personality traits persist throughout life or do we become a different person
as we age?
Birth:
1. Physical development:
(a) Conception: 1 in 5000 eggs well be mature1 in 200 million sperms during the intercourse will
meet the eggwithin 12 hours, the egg nucleus and the sperm nucleus fuse.
(b) Zygote: Conception to 2 weeks. A cell gets divided up to 100 cells. Each cell is predetermined for
each organ. Only 50 % of the fertilized egg survives to the next stage, Embryo.
(c) Embryo: 2 weeks though 8 weeks. The zygote’s outer-wall attaches to the uterine wall forming a
“Placenta,” by which nourishment passes.
(d) 9 weeks to birth. Each organ is sufficiently formed and functional. Can hear sound.
*Note: Teratogens = Chemicals or viruses that can reach the embryo or fetus during the prenatal
development and cause harm (i.e., alcohol, heroin).
*Note: Fetal Alcohol Syndrome = Physical (i.e., facial disproportions) or cognitive (i.e., mental
retardation) abnormalities in children caused by a pregnant mother’s heavy drinking.
*Note: Nature vs. nurture.
(e) Competent newborn: Rooting reflex (touch cheek, turn around, open mouth, find mother’s nipple,
close mouth, and suck). Smell differentiation (i.e., prefers mother’s clothes). Visual/cognitive
ability (i.e., habituation = Decreasing responsiveness with repeated stimulation due to boredom).
Infancy and Childhood:
1. Brain development: Infants have most of the brain cells they would ever have, but their nerves are not
sufficiently interconnected yet (i.e., 3 years). They go through genetically predetermined biological growth
processes (i.e., maturation). Nouns before verbs.
2. Motor development: roll oversitstandwalk.
3. Piaget’s Cognitive development:
*Assimilation (i.e., interpret one’s new experiences in terms of one’s existing schemas: all 4legged animals are dogs) vs.
*Accommodation (i.e., adapting one’s current understandings to incorporate new information).
reaction time decreases due to boredom).
* Stage-theory: Each stage has distinctive characteristics. One after another.
 Sensorimotor stage: 0 to 2 years. Understand the world mostly in terms of looking, touching,
and mouthing (not by thinking). Obtain “object permanence concept” after 6 month. Need to
overcome stranger anxiety.
Other researchers showed that infants were smarter than Piaget claimed (i.e., longer reaction
time to stimuli with wrong numbers, logics, and magic).
 Preoperational stage: age 2 to 6. Use language. Cannot perform simple logical operations. No
Conservation principle (i.e., the quantity remains the same despite the changes in shape).
Egocentric (i.e. brother?). “Cut it in many pieces because I am hungry.” Difficulty to
differentiate dreams/imaginations fro reality (i.e., Santa-Claus). Irreversible thinking
 Concrete operational stage: age 7 to 12. Concrete operations (i.e., A>B, B>C, then A>C) and
reversible thinking, but no abstract reasoning. No hypothetical reasoning (most adolescents
and some adults).
 Formal operational stage: after 12. Hypothetical questioning (i.e., what if ice is
burning?)(Some adolescents and adults).
4. Freud’s psychosexual development
-Humans go through biologically predetermined sequence of stages, each stage focusing on a different
“pleasure-giving zone.”
(a) Oral: Id’s instinctual gratification centers around the mouth (i.e., sucking, biting, chewing) (infancy)
-OverindulgenceOral receptive character (i.e., become dependent, gullible, too accepting/trusting,
supportive, nurturing)
-Under-indulgenceOral aggressive (i.e., cursing, envious, manipulative, exploitative, dominating)
(b) Anal: Centers around the anus.
-Too strict toilet trainingAnal retentive (miser, stingy, hoarding habits).
-Too loose toilet trainingAnal expulsive (disorganized, messy, spending).
(c) Phallic (drives pleasure from self-manipulation) (adolescence).
-Desire for an opposite sex of parents
-Inadequate resolution of complexes
-Oedipus complex Desire for motherFather is too strongcastration anxietyIdentification with
father. Problems: Too much identificationtoo strong superego. Too much castration anxietywant to
prove that they are menExhibitionist & Don Juan type.
Electra ComplexDesire for a fathernot possible Identification with one’s mother.
Also, penis envystrive superiority over men criticizing, ridiculing, and humiliating them.
(d) Latency: Sexual development is at a standstill. Learn social/technical skills.
(e) Genital: With the advent of puberty, sexual tension increases dramatically.
-Ideal personality type. Sexually mature and capable of orgasm, creative and productive at work.
-Inadequate adjustment at this stage lead to various disorders.
5. Social development:
(a) Stranger anxiety: At about 8 months, infants have schemas for familiar faces. At about a year, they
tend to cling tightly to their parents, that is attachment.
(b) Imprinting: The process by which certain animals form a strong emotional tie with a moving
object they observed during a sensitive critical period (i.e., shortly after birth).
(c) Human Attachment develops gradually.
(d) As a function of either positive or negative interaction with caregivers, infants develop one of the
four types of attachment styles.
+ Self +
Secure
Preoccupied
Others
Dismissing Fearful
(e) Parenting: Authoritarian (demanding, controlling), permissive (submit to children’s desires with no
punishment), and authoritative (demanding with reasons).
Adolescence.
1. Physical development: Puberty (the period of sexual maturation). Girls are usually taller than boys before
age 14. But boys become taller after age 14.
2. Kohlberg’s moral development:
(a) Pre-conventional moral development: Before age 9. Interprets moral problems from the point of
view of physical and material reward. Avoid punishment and try to gain reward.
(b) Conventional moral development: Before late adolescence. Begin to care for others and uphold
laws and social rules. Try to meet other’s expectations. Do things to gain social approval or
maintain social order.
(c) Post-conventional moral development: Understand that laws and social orders are relative and
governed by the universal ethical principles. Individualism. (some adolescents and some adults)
3. Erikson’s social development: Each stage of life has its own psychosocial task or a crisis that needs
resolution. Adolescents must develop self-identity.
(a) Infancy (0-1): trust vs. mistrust. I am what I given. Mother. Develop a sense of basic trust if needs
are dependably met.
(b) Toddlerhood (1-2): autonomy vs. shame/doubt. I am what I will to be. Parents. Will do things for
themselves. No spoon-feeding!
(c) Preschooler (3-5): Initiative vs. guilt. Family. I am what I can imagine. Initiate tasks and carry out
plans. Pursue valued goals. “Game.”
(d) Elementary school (6-pubety): Competence vs. inferior. Community and school. “I am what I
learn.” Complete a serious task. Apply themselves to tasks.
(e) Adolescence (10-20s): Identity vs. role confusion. Nation. “I am who I define myself to be.” Try
to refine a sense of self by testing various roles. Try to form a single identity.
(f) Young adulthood (20s to 40s): Intimacy vs. isolation. Community and nation. “We are what we
love.” Form a close relationship or intimacy.
(g) Middle adulthood (40s to 60s): Generativity vs. stagnation. “I am what I create.’ World, nation,
community. Discover a sense of contributing to the world.
(h) Late adulthood (up): integrity vs. despair. “I am what I survives me.” Universe, nation,
community. Reflect on one’s life and feel a sense of success or failure.
Adulthood.
-Aging, intelligence, and memory.
-Crystallized (verbal scores. Slight increase) vs. fluid intelligence (performance score. Reaction time.
Decline).
-Recognition (stable) vs. recall (decline)
-Cross-sectional (decline) vs. longitudinal (somewhat stable)