11 Human Development Developmental psychology The study of changes in physiology cognition and social behavior over the life span WHAT SHAPES A CHILD We are the products of both nature and nurture because genes and experience work together to make us who we are Development Starts in the Womb Zygote Embryo Fetus Physical development o Genes and environment govern much of the human nervous system s prenatal development o Week 4 basic brain areas begin to form Week 7 cells that form the cortex are visible Week 10 cells that form the thalamus and the hypothalamus are visible Week 12 cells that form the R L hemispheres are visible Month 7 the fetus has a working nervous system o Brain development does not stop at birth it continues to develop throughout childhood and adulthood and into old age o Hormones that circulate in the womb influence the developing fetus o Mother s emotional state influences the developing fetus Teratogens Environmental agents that harm the embryo or fetus o The extent to which a teratogen causes damage depends on when the fetus is exposed to it as well as the length and the amount of exposure o Fetal Alcohol Syndrome FAS symptoms consist of low birth weight face and head abnormalities slight mental retardation and behavioral and cognitive problems Brain Development Promotes Learning Newborn is able to process a considerable range of sensory stimuli Acute sense of smell and hearing Their perceptual skills increase tremendously over the first few months of life Grasping reflex Rooting reflex the turning and sucking that infants automatically engage in when a nipple or similar object touches an area near their mouths Myelination and neural connections o Early brain growth Specific areas within the brain mature and become functional Regions of the brain learn to communicate with one another through synaptic connections o Myelination brain s way of insulating its wires It occurs in different brain regions at different stages of development After adolescence the density of synapses remains approximately constant in the 3 brain areas auditory visual and frontal cortex o Synaptic pruning a process whereby the synaptic connections in the brain that are frequently used are preserved and those that are not are lost o Size increase of the brain is due to myelination and new synaptic connections among neurons Attachment Promotes Survival 11 Human Development o Early childhood nutrition affects myelination and other aspects of brain development Sensitive learning periods development o Certain connections are made most easily during particular times in o Critical periods Biologically determined time periods for the o Sensitive periods Biologically determined time periods when specific development of specific skills skills develop most easily Attachment A strong emotional connection that persists over time and across circumstances It leads to heightened feelings of safety and security It motivates infants and caregivers to stay in close contact Attachment in other species o Imprinting the process in which animals attach themselves to adults upon birth o Harlow s Monkeys and Their Mothers Established the importance of contact comfort in social Attachment style development o Separation anxiety o Secure attachment Attachment style for a majority of infants who are readily comforted when their caregiver returns after a brief separation o Avoidant attachment Attachment style in which infants ignore their caregiver when he or she returns after a brief separation o Anxious ambivalent attachment Attachment style in which infants become extremely upset when their caregiver leaves but reject the caregiver when he or she returns o Disorganized attachment Attachment style in which infants give mixed responses when their caregiver leaves and then returns from a short absence o The caregiver s personality contributes to the child s attachment style Chemistry of attachment o Oxytocin It is related to social behaviors including infant caregiver attachment It plays a role in maternal tendencies feelings of social acceptance and bonding and sexual gratification It promotes behaviors that ensure the survival of the young Higher levels of oxytocin is predictive of better maternal attachment 11 Human Development HOW DO CHILDREN LEARN ABOUT THEIR WORLDS Perception Introduces the World Infant research techniques o Preferential looking techniques o Orienting reflex humans tend to pay more attention to new stimuli than to stimuli to which they have become habituated Vision Auditory perception speech o Infants respond more to objects with high contrast patterns o Adults and infants brains have similar brain regions that respond to From the first 3 months of life through adulthood there is a continuity in how the brain processes speech Memory Improves over Childhood Infantile amnesia The inability to remember events from early childhood Inaccurate memory o Young children often have source amnesia o Children are known to confabulate Piaget Emphasized Stages of Development Four stages of development Piaget proposed that during each stage of development children form new schemas He believed that each stage builds on the previous one through 2 learning processes Assimilation The process by which a new experience is placed into an existing schema Accommodation The process by which a schema is changed to incorporate a new experience that does not easily fit into an existing schema Sensorimotor stage birth 2 The first stage in Piaget s theory of cognitive development during which infants acquire information about the world through their senses and respond reflexively o Object permanence The understanding that an object continues to exist even when it cannot be seen Preoperational stage 2 7 The second stage in Piaget s theory of cognitive development during which children think symbolically about objects but reason is based on appearance rather than logic o No understanding of the law of conservation of quantity water in cups of different width height Concrete operational stage 7 12 The third stage in Piaget s theory of cognitive development during which children begin to think about and understand operations in ways that are reversible o Begins to understand the law of conservation of quantity o Children reason only about concrete things o Children do not have the ability to reason abstractly or hypothetically Formal operational stage 12 adulthood The final stage in Piaget s theory of cognitive development