Developmental Psychology Ch 5 Notes 07 23 2012 From womb to tomb Study of physical mental and social changes throughout the human lifespan Life is sexually transmitted 1 egg 200 million sperm Conception the moment at which a female becomes pregnant Ovum the female sex cell or egg Sperm the male sex cell Fertilization the union of the ovum and sperm egg cells and sperm cells each have 23 chromosomes Fertilized cell contains the full set of 23 chromosome pairs The 23rd pair determines the sex Genetic female 23rd pair contains two X chromosomes Genetic male 23rd pair contains an X and a Y chromosome Prenatal Development Stage 1 Zygote the fertilized egg o 2 week period of rapid cell division undifferentiated blastocyst stem cell o Ends with implantation to uterine wall about half do not successfully implant Stage 2 Embryo o prenatal period from 2 weeks through 8 weeks o Begins with implantation to the uterine wall o Placenta and major organs form arms and legs emerge heart beats liver makes red blood cells Stage 3 Fetus o Prenatal period from 8 weeks to birth o Bone cells form neural migration begins o rapid growth of brain and body in final 3 months Prenatal Development Nature AND nurture matter in utero o Critical periods nurture particular stages of development when certain environmental influences strongly impact development o Teratogen substances e g chemicals viruses that reach the embryo or fetus and cause a birth defect The earlier this happens the worse the birth defect neural migration is a critical period o Neural migration movement of neurons from early parts of the fetal CNS to their appropriate final locations Occurs during months 3 5 of the fetal stage Prenatal Programming Teratogen substances e g chemicals viruses that reach the embryo or fetus and cause a birth defect The earlier in pregnancy a woman is exposed the more severe the defects Teratogens o Nicotine low birth weight learning disabilities o Marijuana irritability nervousness tremors o Cocaine respiratory problems learning disabilities seizures o Prescription drugs antidepressants can cause respiratory problems premature birth early motor deficits o Flu and viruses associated with psychological disorders o Stress hormones associated with increased risk of premature o STD s can pass from mother to fetus causing brain damage deafness or blindness birth Prenatal Development Fetal Alcohol Spectrum Disorder FASD o physical and cognitive abnormalities in children caused by a pregnant woman s drinking alcohol o symptoms include facial mis proportions and other physical abnormalities and behavior problems o Leading cause of mental retardation in U S o No known safe amount of alcohol Prenatal Programming Maternal nutrition what the pregnant woman eats and drinks predicts infant health for years after birth o Folic acid and vitamins reduce CNS abnormalities o Iron deficiency associated with cognitive and motor deficits and poor emotional functioning o Maternal malnourishment associated with schizophrenia and antisocial personality disorder o Maternal stress associated with low blood count and anemia Survival Reflexes apgar score Inborn nervous system processes that guide orderly changes in development and behavior stepping grasping Moro startle sucking rooting Maturation and motor development Coordination and agility develop through puberty in a universal sequence o Holding up head rolling over sitting up crawling walking running bike riding skateboarding driving Blind deaf mentally handicapped geniuses Common progression reflects biological maturation Physical Development Vision A infant s vision is initially limited to following objects with their eyes without being able to see details but by the end of their first year they can see clearly Physical Development Senses Newborns facial responses tell us that they have a reasonably well developed sense of taste Newborns respond to touch and distinguish different odors Hearing is fairly well developed newborns prefer human voices to other sounds and can distinguish their mother s voice from that of a female stranger Cognitive Development Cognition All the mental activities associated with thinking problem solving remembering and communicating Initially immature nervous system neural pathways develop with experience pruning occurs 1 yr cerebellum 3 6 yrs frontal lobe Association areas are the last to develop o Brain growth is mostly neural complexity not new neurons o Environment nurture affects brain development o Experience makes connections between neurons Neurogenesis Arborization dense dendritic branching that allows more connections between neurons Synaptogenesis creation of new synapses between neurons Experience is critical to the formation of synaptic connections and neural growth use it or lose it e g Genie Cognitive Development schema a mental concept that organizes and interprets information from experiences with objects and events Children think and organize the world meaningfully but differently than adults kid logic Schemas are inaccurate early in childhood Become more adult like with experience Cognitive Development schemas Assimilation interpreting one s new experience in terms of existing o See a dog learn that it s a dog sees bigger dog knows still dog just bigger Leads to errors biases o Sees cat thinks it s a dog Piaget s Stages of Cognitive Development Accommodation adapting schemas to include new experiences Sensorimotor stage o Piaget s first stage of cognitive development in which the infant uses its senses and motor abilities to interact with objects in the environment Touch feel taste etc o Birth through age 2 o Schemas revolve around sensorimotor info o Developmental Milestones Object Permanence Ability to form cognitive representation that objects exist even when they are out of sight 9 months Peek a boo gets fun Stranger anxiety Preoperational stage o Piaget s second stage of cognitive development in which the preschool child learns to use language as a means of exploring the world o Representing things with words and images but lacking logical reasoning o About ages 2 through 7 o Schemas become more sophisticated o Developmental milestones Egocentrism the inability to see the world through anyone else s eyes TV Do not yet have theory of mind They think if they are hungry everyone else must be hungry Language development Pretend play Schema errors persist Does NOT have conservation Concrete operational o Third stage of cognitive