CH5 DEVELOPING THROUGH THE LIFE SPAN Developmental 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 we age see jean piaget PRENATAL DEVELOPMENT AND THE NEWBORN Conception 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 age Prenatal Development Zygotes 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 the first 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 grow Fetus 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 placed on 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 harm Fetal 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 DEVELOPMENT Brain 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 it properly 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 o As children mature from 4 6 8y o childhood amnesia is giving way and they become increasingly capable of remembering experiences COGNITIVE DEVELOPMENT Cognition all mental activities associated with thinking knowing remembering and communicating JEAN PIAGET believed children constructed their understanding of the world while interacting 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 to make 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 schema ex 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 information Ex child learns that dog is too broad and accommodates by refining the category 1 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 of sight i By 8mo the infant will momentarily look for the hidden object b Stranger anxiety babies around 8mo Developed schema for familiar faces anda when they can t assimilate the new face they become distressed Baby physics infants look longer at unexpected and unfamiliar scenes