CH5: DEVELOPING THROUGH THE LIFE SPANDevelopmental psych major issues:1. Nature & nurture: genetic inheritance (nature) interacts with our experiences (nurture) to influence development?2. Continuity & stages: which parts of development are gradual&continuous, which parts change in separate stages?3. Stability & change: which traits persist through life? How do we change as weage? <see jean piaget>PRENATAL DEVELOPMENT AND THE NEWBORNConception: women are born with all the immature eggs they will ever have (1/5000 will ever mature and be released). Men begin producing sperm cells at puberty, rate of production slows with agePrenatal DevelopmentZygotes: Conception – 2wks. fertilized egg: enters a 2wk period of rapid cell division -> embryo(fewer than half of all zygotes survive beyond the first two weeks. One that survives = you and me)-Zygote undergoes cell division and produces ~100 identical cells within thefirst week. Cells begin to differentiate and specialize in structure and function (brain, intestines, etc)- ~10days after conception, zygote attaches to mother’s uterine wall and begins the ~37week development period-zygotes inner cells -> embryo. Over next 6wks embryo organs form and function, heart begins to beat-zygotes outer cells -> placenta (life-link that transfers nutrients and oxygen)1/270 parents -> twins. Zygote splits in two.-9wks after conception (3mo.): embryo is a fetus and looks human.-During 6mo. Organs develop enough to give fetus chance of survival if born prematurely. Embryo: 2wks-8wks the developing human organism from about 2wks after fertilization-2nd month. At 40 days=spine is visible and arms and legs begin to growFetus: 9wks-birth. Developing human organism from 9wks after conception – birth. Facial features, hands, feet formed.6mo: microphone readings inside uterus show fetus is responsive to sound and exposed to sound of mother’s muffled voice. Immediately after birth, newborns prefer mothers voice to others.7mo: fetuses demonstrate learning by adapting to a vibrating honking device placedon the mother’s abdomen. Fetuses get used to the honking like we get used to train sounds. 4 wks later, they recall the sound.Teratogens: agents (chemical and viruses) that can reach the embryo/fetus during prenatal development and cause harmFetal Alcohol Syndrome (FAS): physical and cognitive abnormalities in children caused by a pregnant woman’s drinking. Severe cases: noticeable facial disproportions, smaller heads.Habituation: decrease in responding with repeated stimulation. With repetition, responses weaken. “boredom” with familiar stimuli.Ex: researchers used visual preference to “ask” 4month olds how they recognize cats and dogs. First showed images of either cats or dogs. Then showed them hybrid cat-dog images. .(after seeing images of cats) The infants found the hybrid animal with the dog’s head more ‘interesting’ based on how long they stared at the image.*Infants focus first on the face, not the body. The hybrid had a cats body but a dogs head. Since the infant was shown a bunch of cats before, they only paid attention to the dog’s face not the cat’s body.Maturation: Biological growth processes (nature) that enable orderly changes in behavior, uninfluenced by experience. Genetic growth tendencies are inborn. Maturation (nature) sets the basic course of development; experience (nurture) adjusts it.PHYSICAL DEVELOPMENTBrain Development: developing brain cortex overproduces neurons (# peaking at 28wks/7mo) then subsides to a stable ~23 billion at birth.-3-6y.o most rapid growth was in: frontal lobes -> rational planning*pre-schoolers display rapidly developing ability to control their attention & behavior.-association areas (thinking, memory, language) = LAST cortical areas to develop. As they develop, mental abilities surge. Fiber pathways supporting language and agility -> puberty. Use-it-or-lose-it pruning process* (shuts down unused links, strengthens others)Motor Development: physical development is universal. Babies roll over before they sit unsupported, crawl before they walk. = maturing nervous system, NOT imitation of what they see (blind babies crawl before they walk too).*individual differences in timing. Ex: in U.S.- 25% babies walk by 11mo, 50% within a week after first birthday, 90% by 15mo old.*Genes guide motor development: identical twins begin walking on nearly the same day. Maturation – of the rapid development of the cerebellum (back of brain) – creates readiness to learn walking at about age 1. Experience before that age has limited effect.Brain maturation & Infant Memory: Infantile amnesia- ex: someone who experienced an emergency fire evacuation at 3y.o will not be able to recall itproperly, will probably say they were already outside when the alarm sounded. But if they were 4-5y.o they can recall it when they’re older.Avg. age of earliest conscious memory = 3.5 y.oAs children mature from 4-6-8y.o, childhood amnesia is giving way and they become increasingly capable of remembering experiences.COGNITIVE DEVELOPMENTCognition- all mental activities associated with thinking, knowing, remembering and communicatingJEAN PIAGET- believed children constructed their understanding of the world whileinteracting with it. A child’s mind develops through a series of stages from the newborn’s simple reflexes -> adult’s abstract reasoning power. Minds experience spurts of CHANGE -> STABILITY as they move from one lvl to the next*core idea: the driving force behind out intellectual progression is a struggle tomake sense of our experiences.The maturing brain builds schemas: concepts/mental molds that organize and interprets experiences/information by adulthood we have built schemas ranging from ‘cats’ and ‘dogs’ to our concept of love.*assimilation: interpreting out new experiences in TERMS of our EXISTING schemaex: having a schema for a dog, a child may call all four-legged animals ‘dogs’but as we interact with the world, we use: Accomodation: adapting our current understandings (schema) to incorporate new informationEx: child learns that ‘dog’ is too broad and accommodates by refining the category1. SENSORIMOTOR STAGE- birth-2y.o: experiencing the world through senses and actions (looking, hearing, touching, mouthing, grasping) out of sight out of mind, live in the present.a. Object permanence: infants younger than 6mo seldom understanding that things continue to exist when they’re out