HUMAN GROWTH AND DEVELOPMENT LIFE-SPAN EXAM 1 DISCUSSION LIFESPAN CHAPTER 1 INTRODUCTION 1. How do the lives of Ted Kaczynski and Alice Walker illustrate the questions explored in the course textbook? • One question is what leads one person, full of promise and potential to commit acts of brutal violence and • another to change poverty and trauma into a literary treasure chest. • Another question is how are different lives unique. • A third question is how does understanding lifespan development illuminate the nature of development and • how science seeks to ask and answer questions about development. 2. What is the importance of studying the development using the lifespan perspective? • Studying development using the lifespan perspective illustrates how lives are unique • contain information about who we are • how we came to be the way we are and • where future will likely lead us. • shows that development involves both growth and decline as well as changes that occur from conception until death. 3. What are 8 characteristics of the lifespan perspective? • A. lifelong – includes changes from conception until death • B. multidimensional – body, mind and emotions and relationships change and affect each other throughout life; • involves biological, cognitive and socioemotional dimensions • C. multidirectional – in all phases of life some abilities improve while others decline; • example is ability to learn second and third languages decreases as we grow older. • D. plastic – involves capacity for change and growth during different stages of life in terms of cognition, physiology and social and emotional functioning. • E. multidisciplinary – lifespan perspective integrates information from psychology, sociology, anthropology, neurology and medicine to help us to understand development • F. contextual – lifespan perspective emphasizes that development occurs in a particular setting or context (cultural, social, geographical). • context of development has 3 types of influence on development: 1)normative agegraded; 2)normative history-graded; and 3)nonnormative. • G. involves 3 goals of growth, maintenance and regulating loss of functioning. • H. involves interaction of factors associated with biology, culture and individual experiences; • biology includes physiological and genetic factors suggesting tendencies and possibilities; • culture provides environment and context; • individual experience contributes a unique dimension to each person’s life. 4. What are 4 contemporary concerns regarding lifespan development? • A. health and well-being – • mental and physical health professionals help us to improve our physical and mental state and feeling of well-being; • physical and psychological lifestyle and state affects both mental and physical health. • B. parenting and education – • Understanding lifespan perspective helps us to answer questions about pressures on the family and problems facing educators; • other issues: child care, divorce, parenting styles, intergenerational relationships, early childhood education, efforts to promote lifelong learning. • C. social and cultural contexts and diversity – • 4 concepts: • 1)culture: behavior patterns, beliefs of a particular group; • 2)ethnicity: related to cultural heritage, nationality, race, religion and language; • 3)socioeconomic status: • position in society with regard to occupation, education and economic resources; • 4)gender: psychological and social and cultural experience of being male or female. • D. social policy – • government’s course of action for protecting and promoting the welfare of citizens; • involves values, economics and politics; • special concern for children and elderly individuals. 5. What are 4 features of the nature of development? • • • • A. biological, cognitive and socioemotional processes 1)biological processes: changes in physiology; examples, genes from parents, brain development, height and weight gain, hormonal changes in adolescence; • 2) cognitive processes: • changes in thinking, intelligence and language; • examples, watching a crib mobile, creating multiword sentences, imagining what is would be like to president of the United States. • 3)social and emotional processes: • changes in relationships with other people, emotions and personality; • examples, infant smile in response to cuddling, • toddler’s aggressive behavior toward a playmate, • mutual affection expressed by elderly couple. • B. periods of development – • time frame in life characterized by certain features, usually involving an 8-period sequence; • 1)prenatal period: • conception to birth; • from single cell to complete organism with complex brain and nervous system capable to variety of behaviors; • 2) infancy: • birth to 18-24 months; • extreme dependency on adults and other older individuals; • psychological activity begins; • • • • • 3) early childhood: age 2 to 5 or 6; preschool years; become more self-sufficient; learn school readiness skills such as following instructions and recognizing letters and colors; • • • • 4) middle and late childhood: from 6 to 11 or 12; elementary school years; master basic skills of reading, writing and arithmetic; • achievement is central theme; • person shows increasing self-control; • • • • 5) adolescence: transition from childhood to early adulthood; from 10-12 to age 18-22; begins with rapid physical changes characteristic of puberty; • major goals becoming independent and developing an individual identity; • thinking more logical and abstract; • 6) early adulthood: • from late teens through 30’s; • establish personal, social, emotional and economic independence; • beginning career development; • select life partner; • start family and child rearing; • 7)middle adulthood: • from early 40’s until around age 60; • expand personal and social involvement and responsibility; • assist next generation; • reach and maintain career satisfaction. • • • • 8) late adulthood: from 60’s and 70’s until death; time of review and reflection; retirement and adjusting to decreasing strength and health; • longest span of any developmental period • C. conceptions of age • 1)chronological age: number of years since birth; • 2)biological age: describes biological health and functional capacity of vital organs, such as heart, lungs, kidneys, circulatory system; • 3)psychological age: measure of adaptive capacities, including ability to learn, establish and maintain motivation, be flexible and think clearly. • D. Developmental issues start here mon sep7 • 1) nature and nurture: • extent to which our development is affected by biological inheritance and environmental experiences; • evolutionary and genetic tendencies (nature) as well as environmental setting result in shared growth and developmental experiences; • some controversy as to how much nature and nurture influence development. • 2) stability and change: • involves degree to which early traits and characteristics persist throughout life; • some disagreement about amount of stability or change we are likely to experience; • remember idea of plasticity suggesting potential for change exists throughout the lifespan. • 3)continuity and discontinuity: • focus on degree to which development is gradual and continuous or • occurs in distinct stages; • usually continuous within stages and discontinuous or discrete between stages. • 6. Describe 6 theoretical approaches that help understand development –>theory = set of related ideas about development that explain what happens and why • • • • • • A. psychoanalytic B. Cognitive C. Behavioral and Social Cognitive D. Ethological E. Ecological F. Eclectic • Testing a theory involves using scientific method • a. state a process or problem to be studied; • b. collect research information or data; • c. analyze the data; • d. draw conclusions; • e. share findings with others. • A. psychoanalytic – • assumes development is mostly unconscious and influenced by emotions; • emphasizes behavior consists of mainly surface characteristics; • true understanding involves analyzing symbolic meaning; • stresses early childhood experiences. • Examples of psychoanalytic theories from Sigmund Freud and Erik Erikson; • Freud suggested 5 stages of development including • oral, anal, phallic, latent and genital; • personality depends on how we resolve conflicts between sources of pleasure and demands of reality at each stage. • Erikson proposed 8 stages of development; • each stage involves unique developmental task presenting the person with a crisis to resolve. • Erickson’s crises are turning points characterized by increased vulnerability and potential. • Erickson’s stages: • 1)trust vs mistrust – first year • 2)autonomy vs shame and doubt – second year • 3)initiative vs guilt – ages 3-5 • • • • • 4) industry vs inferiority – ages 6-12 5)identity vs role confusion – ages 13-19 6)intimacy vs isolation – 20’s -30’s 7) generativity vs stagnation – 40’s-50’s 8)integrity vs despair – 60’s -death • B. Cognitive theories – • emphasize effects of conscious thoughts on development. • Examples of cognitive theories • a. Piaget’s cognitive stages, • b. Vygotsky’s Sociocultural cognitive theory, • c. information processing theory. • a. Piaget: proposed 4 stages of cognitive development: • sensorimotor, • preoperational, • concrete operational and • formal operational; • suggested we actively construct our understanding of the world; • Cognitive understanding involves organization (deciding how to separate ideas and describe how the ideas relate to each other) and • adaptation (adjusting to environmental demands). • Each stage is age-related and characterized by a distinct way of thinking that is qualitatively different from thinking in other stages. • Description of Piaget’s cognitive stages: 1)sensorimotor • birth to 2 years; • coordinate sensory experiences with physical motor or muscle responses; • 2)preoperational • 2-7 years; • represent world with words, images and drawings; • lack ability to perform operations • internalized mental actions • allow child to accomplish mentally what could previously be done only physically. • 3)concrete operational • 7-12 years; perform operations involving objects; • reason logically when reasoning applied to specific or concrete examples. • • • • 4)formal operational from 11-15 through adult life; think in abstract and logical terms; develop images of ideal circumstances used for comparison with reality; • think about future possibilities; • Formal operations more systematic in problem solving compared to earlier stages; • develop hypotheses about why something happens and test hypotheses. • b. Vygotsky’s sociocultural cognitive theory: • believed child actively constructs knowledge about the world; • emphasized effects of social interaction and culture; • believed child development inseparable from social and cultural activities; • Vygotsky proposed cognitive development involves learning to use social inventions such as language, math, memory strategies; • believed social interaction with skilled adults and peers essential to cognitive development; • learn through social interaction to use tools needed for adaptation and success in a particular culture. • c. Information processing theory: • emphasizes manipulating and monitoring information • developing strategies about information; • propose a gradually increasing capacity for processing information • allowing a person to acquire increasingly complex knowledge and skills; • IP theory proposes people perceive, encode, represent, store and retrieve information while thinking; • important to learn effective information processing strategies. • C. Behavioral and social cognitive theories • development described in terms of behaviors learned through interaction with the environment. • a. behaviorism: • study scientifically only what we directly observe and measure; • examples: • Skinner’s operant conditioning • Bandura’s social cognitive theory • 1)Skinner’s operant conditioning theory = • consequences of behavior produce changes in probability of behavior occurring; • behavior followed by reward more likely to occur later; • behavior followed by punishment or no consequences less likely to occur in the future; • Skinner’s key to development: behavior rather than thought and feelings; • emphasize development as pattern of behavioral changes resulting from rewards and punishment. • 2)Bandura’s social cognitive theory • propose behavior, environment and personal+cognitive factors key to development; • emphasize cognitive processes important link to environment and behavior; • early focus on observational learning(imitation or modeling) • we learn by observing others; • Bandura’s cognitive link to observational learning: person representing behavior cognitively or mentally and • adopting the observed behavior; • most recent model of social cognitive theory has 3 elements: • behavior, personal cognition and environment; • person develops while experiencing confidence about controlling success in life • based on cognitive strategies learned and used. • D. Ethological theory – • stresses behavior influenced by biology and genetics; • behavior characterized by critical periods or sensitive periods • or special time frames associated with the absence or presence of experiences having lasting influence on the person’s development. • Examples – Konrad Lorenz and John Bowlby • Lorenz’s critical period is important for imprinting very early in life as with baby geese. • Sensitive periods similar to Bowlby’s idea of a time period in the life of human infants. • 1) Konrad Lorenz promoted ethology • the study of animal behavior with emphasis on the behavioral patterns that occur in natural environments. • Lorenz studied behavior of greylag geese who follow mother soon after hatching; • Lorenz separated a group of eggs from one mother goose; • Group A eggs were returned to mother goose for hatching and care; • these baby geese later behaved as expected; • Group B eggs were hatched in an incubator and saw “mother” Lorenz immediately after hatching; • later all baby geese placed in a box with a lid; • when lid was lifted Group A babies headed for mother goose as expected; • Group B babies headed for “mother”Lorenz; • Lorenz called the process imprinting, a rapid innate learning involved in attachment to the first moving object viewed after hatching. • 2) John Bowlby proposed important application of ethology to development; • suggested a child’s attachment to caregiver during first year of life is important influence; • if attachment is positive and secure, future development is likely positive; • if attachment is negative and insecure, future develop likely characterized by problems. • E. Ecological theory – emphasizes environmental factors effect on development • 1. Bronfenbrenner’s ecological theory: • development reflect effects of 5 environmental systems: • a. microsystem – setting in which person lives, such as family, peers, school, neighborhood; • most direct interaction with social agents such as parents, teachers and peers; • person helps to construct developmental setting; • b. mesosystem – • Controls relations between microsystem and connections between contexts; • example: relationship between family and school or school and church; • c. exosystem – links between social setting where individual is not active and person’s immediate context; • example – child’s experience at home influenced by mom’s experience at work; • d. macrosystem – • culture in which individual lives • Includes behavior patterns, beliefs and products of a group shared among different generations; and • e. chronosystem – • pattern of environmental events and transitions over life course • plus sociohistorical circumstances; • examples – divorce as transition; • recent increased career opportunities for women as sociohistorical circumstances. • Recent addition of biological influences has resulted in bioecological theory, • heavy emphasis on ecological influences. • F. Eclectic theoretical orientation – • All theories together form a more complete picture of development. • Psychoanalytic theories best at explaining unconscious mind. • Erikson’s theory best to explain adult development. • Piaget and Vygotsky + information processing theory best to explain cognitive development. • Behavioral and social cognitive + ecological theories best to explain environmental influences. • Ethological theory best to explain effects of biological factors and influence of sensitive periods. • Course textbook best described as eclectic in orientation. 7. Describe 3 features of research in development • A. 5 methods for collecting data, • B. 3 research designs; • C. 3 time frames for research • • • • A. Methods for collecting data: 1)observation: must be systematic; know what you are looking for; know when, where and how to make observations and how to record observations; • where to make observations – in laboratory or everyday life; • observe scientifically in controlled conditions in laboratory; • drawbacks to lab: • unnatural setting, • participants aware of observation, • people willing to come to lab may not be typical; - • participants could be intimidated by lab setting; • naturalistic (everyday life) observations: • eg observing parents and children in science museum with no attempt to control or influence behavior. • Observations easier to relate to typical experiences • 2) surveys and interviews: • ask people directly; • survey or questionnaire using standard set of questions; • useful to get information on wide range of information; - • Difficulty with surveys and interviews: • people tend to give what they consider socially acceptable answers. • 3)standardized tests: • uniform procedure for administering and scoring; • allow comparison with other people; • gives information about individual differences; • example: Stanford-Binet intelligence test (Ch 7); - • Criticism of standardized tests: • assume behavior is consistent and stable; • however, personality and intelligence, commonly studied using standardized tests, can vary with situation or setting. • 4) case study: • In-depth study of single individual or a few individuals; • provides information for a specific person or a small group such as a family; • information can come from interviews and medical records; - • cautious about generalizing to other individuals or families; • unknown reliability. • 5. physiological measures: • often used to study development at different times during lifespan; • example: blood levels of hormones in adolescence, early, mid and late adulthood; • also neuroimaging such as functional Magnetic Resonance Imaging (fMRI) • use electromagnetic waves to construct images of brain tissue and biochemical activity. • 3 research strategies • 1. descriptive - all methods previously listed can be used in descriptive studies; • cannot be used to support cause and effect or to predict behavior; • can be source of extensive information • 2. correlational – • helps to predict how people will act, think, and feel in the future; • goal: describe relationship between 2 or more variables; • example: ask if children of permissive parents are likely to show decreased self-control; - • analyze data statistically using correlation coefficient (number ranging from +1.00 to 1.00); • positive number indicates variables are related in the same direction; • negative number shows variables are related in opposite direction; - • higher number shows stronger relationship and better prediction; • lower number shows weaker relationship and worse predictions. • 3. Experimental research – • experiment is carefully controlled procedure; • can determine cause and effect relationships; • • • • • 2 types of variables: Independent (controlled by experimenter; is a potential cause; manipulated by experimenter independently of other variables) and- • dependent • (can change in the experiment in response to the independent variable; • dv’s are measured for potential effects). • Example: • study whether meditation could cause newborns sleeping and breathing patterns to change; • Group A moms meditate and Group B moms do not; then- • study newborns breathing patterns from both groups to see whether there is a difference to test the hypothesis; • • • • • • 2 types of groups: Experimental- (receives the experimental treatment) and Control (does not receive experimental treatment; provides a baseline comparison level); • random assignment to experimental and control groups important • reduces effects of experimenter bias and participant expectations. • C. 3 Time spans or Time frames of research: • cross-sectional; • longitudinal, • cohort effects • 1. cross-sectional – • compares several groups of participants of different ages at same time; • example: study 3 groups of children, ages 5, 8 and 11; • can be compared using variety of independent and dependent variables such as IQ, memory or peer relationships; - • advantage: • economical in time, money and effort; • drawback: no information about stability and change across time in factors studied for individual participants; • 2. longitudinal – same individuals studied over a certain period of time, such as 5, 10 or 20 years; • gives information about stability and change for individuals as well as influence of early experience for later development; • drawbacks: • expensive and time-consuming; • participants may drop out for variety of reasons, creating a source of positive or negative bias. • 3. cohort effects – • cohort is group of people born at similar point in time; • share similar experiences; • example: live through Korean, Vietnam or Middle Eastern war; • shared experiences result in range of differences compared to other cohorts; - • Cohort effects result from time of birth, era or generation • not necessarily related to actual age. 8. How can research designer make sure the research is ethical? • Important to know rights of research participants, whether you are experimenter or participant; • proposed research studies at colleges and universities must meet standards imposed by research ethics committees; • American Psychological Association has established important ethical guidelines; • research participants should be protected from mental and physical harm. • 4 important issues: • a. informed consent (know what research involves and possible risks); • b. confidentiality (keep all data confidential and, if possible, completely anonymous); • c. debriefing • (after study discuss purpose of research and methods used); • d. deception • (if deception used, ensure deception will cause no harm; • afterward tell participants about the nature of the study). LIFESPAN CHAPTER 2 – BIOLOGICAL BEGINNINGS • 1. What ideas do the stories of the Jim and Jim twins and the giggle sisters illustrate about genetic heritage and biological factors effect on development? • A. Jim and Jim, separated at birth, demonstrate the effects of genetic similarity. Similar jobs, vacations, cars, pet names, wife names, personal habits, and physiological symptoms. • B. Daphne and Barbara (giggle sisters) also separated in young infancy, also showed similar characteristics. • C. Can other factors cause similarities? twins share some experiences as well as genes. • 2. What are features of the evolutionary perspective? • A. Natural selection and adaptive behavior - natural selection: process by which individual in a species best adapted survive and reproduce; • Charles Darwin suggested struggle for food, water and resources occurs among young because some don’t survive; • survivors who reproduce pass genes to next generation; • those best adapted to survive leave more offspring; • B. Evolutionary psychology: • emphasizes importance of adaptation, reproduction and survival fittest in shaping behavior; • fit = ability to bear offspring who are capable of surviving to have offspring of their own; • natural selection favors behavior that increases reproductive success; • David Buss (2008) suggests evolution influences decisions, aggressive tendencies, emotions and mating choices; • example: among a culture of hunters and gatherers, those who hunted needed certain physical traits as well as cognitive abilities to be successful hunters; • successful hunters could have passed these traits to their offspring. • C. Developmental evolutionary psychology: • application of evolutionary psychology to understand development; • extended human childhood evolved because humans required time to develop large brains and learn about human society; • many psychological mechanisms are domain specific, • applying only to specific aspects of individual makeup, such as information processing; • the idea that mind is not a general purpose device; • specific information processing skills developed contributing to ancestors task success; 3. What are some features of the genetic foundations of development? • • • • A. Genetic process: begin life as single cell; contains genetic code; nucleus of each cell contains chromosomes, made of DNA; • genes are short segments of DNA which direct cells to reproduce cells and assemble proteins; • hormones circulate in the blood and activate or deactivate genes; • hormone flow also influenced by environmental conditions such as light, nutrition and behavior • B. Genes and chromosomes: 3 processes- 1. mitosis,2. meiosis and 3.fertilization. • 1. mitosis: regular cells (all except sperm and eggs) reproduce by mitosis, cell’s nucleus reproduces itself and creates exact duplicate with 46 chromosomes • 2. meiosis: reproductive cells (sperm and egg) duplicates chromosomes then divides again, resulting in 4 cells, each with 23 chromosomes; • 3.fertilization: egg and sperm join to form a single cell or zygote; • each parent contributes ½ the genetic information; • chromosome structure for males and females differ at 23rd chromosome pair- male, XY and female, XX • C. Sources of variability: • combining genes of 2 parents results in increased variability; • provides more characteristics for natural selection; • 3 sources of variability: • 1)chromosomes in the zygote not exact copies of parent chromosomes; • in forming sperm and egg, pairs of chromosomes are separated; • later which chromosomes in each pair go to the sperm or egg is random; • 2)variability from DNA; • sometimes random effects resulting from mistakes in cell metabolism or environmental damage lead to mutated genes; • 3)differences between genotype (complete genetic potential) and phenotype (observable characteristics) • D. Genetic principles: • 1)dominant and recessive genes; • dominant genes influence phenotype even when only one gene present; • recessive genes require presence of both genes for the trait to be observed. - • • • • examples of dominant traits: brown hair and far-sightedness; Recessive traits: blonde hair and near-sightedness; • 2)sex-linked genes: • most mutated genes are recessive; • if mutated gene is on X chromosome, trait is X-linked with different implications for males and females; • males have only one X chromosome, so the harmful gene may lead to an x-linked disease;- • females have 2 X chromosomes so healthy gene is more influential; • more males than females tend to have xlinked diseases; • example of x-linked disease more of problem for males is fragile X syndrome. • 3)polygenic influence – • some traits reflect the influence of several genes, not just one; • examples are height, weight, and intelligence • 4. Chromosome and gene-linked abnormalities: • a. chromosome abnormalities – • • • • abnormal number of chromosomes (Down syndrome; cause of MR and certain physical features; usually caused by extra copy of chromosome #21; • round face, flattened skull, extra fold of skin on eyelids; • retarded motor and mental abilities; ) • • • • sex-linked chromosome abnormalities (mostly involve extra X or Y chromosome; or missing X chromosome in females; Klinefelter’s syndrome- males are tall and have enlarged breasts and extra X chromosome; XXY; • Fragile X syndrome – • X chromosome constricted or sometime in pieces; • results in lower level intelligence or learning disability; • • • • Turner Syndrome – in females missing X chromosome; X0 instead of XX; short height; webbed neck skin; math difficulties; verbal ability usually good; • XYY – males with extra Y chromosome; no reliable psychological characteristic pattern; • 5. Gene-linked abnormalities – • defective genes; • a)phenylketonuria – (PKU); not process phenylalanine properly; • recessive trait; • easily detected in newborns; • illustrates genotype/phenotype differences; • • • • • b)sickle cell anemia – most often in African Americans; impairs red blood cells; RBC shaped like sickle or hook; cannot carry oxygen and dies quickly; • • • • • • • c. other examples: cystic fibrosis, diabetes, hemophilia, Huntington Disease, spina bifida, and Tay-Sachs Disease. 4. Heredity and Environment Interaction Features • A. Behavior genetics: • seeks to discover influence of heredity and environment on individual differences in human traits and development • Uses study of twins and adopted children; • twin study • compares behavioral similarity of identical twins with that of fraternal twins; • if behavior or trait is more similar in identical twins, can conclude trait has stronger genetic basis; • adoption study – • studies whether behavioral or psychological characteristics of adopted children are more similar to those of adopted parents or biological parents. • B. Heredity-environmental correlations: • involve heredity-environment correlations or influence of genes on environments to which exposed; • 3 types of heredity-environment correlations; • B1. passive genotype-environment correlation: • biological parents provide rearing environment for their children • (intelligent skilled readers provide environment that enhances reading skills); • B2. evocative genotype-environment correlation: • child’s characteristics elicit certain type of environmental stimulation – • smiling children receive more social stimulation than children who don’t smile; • B3. active genotype -environment correlation – • children seek out stimulating environments; • example, outgoing children actively seek out social contexts to interact with people; • C. Epigenetic view: • development results from ongoing, mutual interchange between heredity and environment. • Example: baby inherits genes from both parents; • before birth, toxins, nutrition and stress can influence development and - • make some genes stronger and other genes weaker; • during infancy heredity and environment continue to act together to influence genetic activity as well as nervous system activity; • D. Conclusions about heredity and environment: • relative contribution of H and E is not additive • there is a no certain percentage contribution from H and a certain percentage from E; • genetic influence occurs throughout life, not just at conception; • • • • emerging view: complex behaviors have a genetic loading – or tendency to act/think/feel in certain ways; environment is also complicated, including parenting style, family dynamics, school and neighborhood quality. • 5. Prenatal development: • begins when sperm and egg join in process of fertilization 5A. Course of prenatal development: • • • • • • • 3 periods 5A1. germinal period: 2 weeks following conception; creation of zygote; cell division; and attachment to wall of uterus; • cell division process- mitosis; • cell specialization • (blastocyst or inner mass of cells becomes the embryo; • trophoblast or outer layer of cells provides nutrition and support; • implantation (attach to uterine wall 10-14 days after conception. 5A2. embryonic period: • 2-8 weeks after conception; • cell differentiation intensifies; • support systems develop and organs form; • 3 layers of cells develop from blastocyst: • endoderm or inner layer gives rise to digestive and respiratory systems; • ectoderm or outer layer becomes the nervous system, sensory receptors and skin parts; • mesoderm or middle layer becomes circulatory system, bones, muscles, excretory system and reproductive system; • life support systems from trophoblast: • amnion, umbilical cord and placenta; • amnion is a bag or envelope containing a clear liquid controlling temperature and humidity; • umbilical cord, 2 arteries and a vein connect the embryo to placenta; • placenta, a disk-shaped group of tissues made up of small blood vessels connecting embryo to mother; - • very close but not joined; • in placenta, small molecules such as oxygen, water, salt, digestive waste pass back and forth; • Larger molecules cannot pass back of forth • 5A3. fetal period: • 2-9 months after conception; • at 3 months, fetus is about 3 inches long weighs 3 oz; • can move arms and legs, • open and close mouth, • can distinguish features such as face, forehead, eyelids, nose and chin; - • • • • genitals identify fetus as male or female; 4th month, mom can feel baby move; 5th month, 12 inches, close to 1 lb, skin structures form such as toe nails, and fingernails; • 6th month, eyes and eyelids formed; • layer of hair on head; - • grasping reflex and irregular breathing present; • 7th month, 16 inches, 3 lbs, • considered able to survive outside mother; • last 2 months fatty tissues develop; • functions of heart and kidneys increase; • gains height and weight; at birth, average American baby 7 ½ lbs; 20 inches. 5B. Prenatal Tests, • • • • include ultrasound, chorionic villus sampling, amniocentesis, maternal blood screening 5B1. ultrasound: • usually at 7 weeks and other times; • noninvasive; • high frequency sound waves directed toward mother’s abdomen; • echoes from these sound waves transformed into visual representations of baby’s internal structures; - • can detect structural abnormalities such as microcephaly (very small brain). • 5B2. chorionic villus sampling: • 10-12th week; • screen for genetic defects and genetic abnormalities; • tissue sample from placenta analyzed; results in 10 days; 5B3. amniocentesis: • 15-18 weeks; • sample of amniotic fluid analyzed for chromosome or metabolic disorders; • later tests more accurate; • earlier tests more useful to plan pregnancy; small risk of miscarriage; 5B4. maternal blood screening: • identifies elevated risk for birth defects such as spina bifida or Down Syndrome; 5C. Infertility and Reproductive Technology: • 10-15% couples experience difficulty conceiving a child after 12 months regular intercourse • cause may be associated with woman’s failure to ovulate, • blocked fallopian tubes • or man’s lack of sperm or low-mobility sperm; • surgery can correct some problems • Also hormone therapy is possible • in vitro fertilization may also be used (egg and sperm combined outside the other 5D. Hazards to Prenatal Development: • 5D1. General Principles: • 5D1a. teratogens – • anything that could potentially cause birth defect or damage cognitive or behavioral outcomes; • include drugs, incompatible blood types, environmental pollution, infectious diseases, nutrition problems, maternal stress or parental age; • 3 characteristics of teratogens: • *higher more intense dosage has greater effect; • *type and severity of abnormality linked to genotype of mother and baby; • *time of exposure has different effects, depending on whether occur at certain points in developmental sequence; • damage during germinal period can prevent implantation; • exposure during embryonic period has higher risk of structural defect early in this period. 5D2. prescription and nonprescription drugs: • • • • examples include antibiotics like streptomycin and tetracycline, antidepressants, hormones such as progestin and synthetic estrogen; • nonprescription drugs such as diet pills and aspirin. 5D3. psychoactive drugs act on mother’s nervous system • • • • alter states of consciousness, modify perception and change moods Examples: caffeine, alcohol, nicotine, cocaine, methamphetamine, marijuana and heroin. • caffeine results in small risk for spontaneous miscarriage and low birth weight; • alcohol can result in fetal alcohol syndrome with facial deformities, defective limbs, likely cognitive deficiencies; • nicotine can result in premature birth, low birthweight, fetal and neonatal death, respiratory problems and sudden infant death syndrome; • cocaine use can result in reduced birth weight, length, and head circumference, • impaired motor performance, • lower arousal, • less effective self-regulation, • higher excitability at 1 month, • attention deficit and learning disability in school; • methamphetamine is a stimulant • can speed up the nervous system, resulting in higher infant mortality, low birth weight, developmental and behavioral problems; • marijuana use by mother can result in memory and information processing deficiencies; • depressive symptoms and be associated with later drug use by the child; • heroin can result in withdrawal symptoms such as • tremors, irritability, abnormal crying, disturbed sleep, and impaired motor control. 5D4. Incompatible blood types: • differences in surface structures of red blood cells associated with different blood groups (A,B, O and AB) and • Rh factor: if present, individual is Rh+ and if absent, individual is Rh-. • If Rh- woman conceives with Rh+ man, • baby’s blood type may be Rh+. • Mother’s immune system will produce antibodies that will attack the baby’s RBCs. • First baby will be ok; later children increasingly at risk; • serum (Rhogam) given to mom will prevent producing the antibodies; • blood transfusion either before or after birth also possible. 5D5. maternal diseases: • Viruses can cross placental barrier, • rubella or German measles causes highest risk in 3-4th week of pregnancy; • vaccine possible for mom; • • • • syphilis: more damage 4 mos + after conception; damages organs after formation; eye and skin lesions, if present at birth cause problems in central nervous system and gastrointestinal tract; • genital herpes, • baby infected if exposed to virus in mom’s birth canal or vagina; • AIDS, sexually transmitted syndrome; caused by virus that destroys body’s immune system; • infection possible 3 ways, - • A. during gestation across placenta, • B. during delivery if exposed to mother’s blood, • C. after birth through breast feeding; • effects for baby: 1)infected and shows symptoms, 2)infected and shows no symptoms, 3)not infected; 5D6. Maternal diet and nutrition: • developing baby depends on mom for nutrition from mom’s blood; • total calories and intake of proteins, vitamins and minerals; • if mom overweight, higher risk of still birth and neonatal death; • folic acid or B-complex vitamin; • lack linked to neural tube deficits leading to spina bifida, a potentially fatal defect in spinal cord development; 5D7. Emotional states and stress: • intense fears, anxieties and other emotions; • increased adrenaline in mother’s body restricts blood flow to uterus and lowers available oxygen for baby; 5D8. maternal age: • especially adolescence and 35+ can lead to still birth and higher infant mortality; • link to Down Syndrome; • older mothers have higher risk for babies with low birth weight, premature birth and fetal death. 5D9. paternal factors: • exposure to lead, radiation, pesticides and other chemicals; • Can result in sperm abnormalities; • diet low in Vitamin C can lead to increased birth defects and cancer; • cocaine use can result in male-related infertility; • older fathers can have children with increased risk of Down Syndrome, dwarfism and Marfan syndrome. 5D10. Environmental hazards •radiation, •toxic wastes, and •chemical pollution with potential effects on eggs and sperm 5E Prenatal care: • involves regular schedule of visits for medical care, • screening for manageable conditions and treatable diseases; • comprehensive educational, social and nutritional services. 6. Birth and Postpartum Period • • • • • • 6A. Birth process: 3 stages 6A1a stage 1: uterine contractions; 15-20 minutes apart; last up to 1 minute; cervix stretches and opens; - • contraction rate increases to 2-5/minute; • intensity increases; • at end of stage 1 cervix opens to about 4 inches; • lasts about 12-24 hours for first pregnancy; 8 hours for later births; 6A1b stage 2: • • • • baby’s head moves into vagina; ends when baby is completely out; contractions come faster, about 1/minute; lasts 1 ½ hours to 45 minutes. 6A1c stage 3: • afterbirth; • placenta, umbilical cord and other tissues expelled, lasts a few minutes. 6A2 child birth setting and attendants: • in US mostly in hospitals; • also home delivery and free-standing birth centers; • assistance usually from physicians (obstetricians), commonly males; • in US fathers usually present; • other cultures, men may be excluded; • midwives common throughout the world, less common in US; • doula – a caregiver providing physical, emotional and educational support to the new parents; 6A3. Methods of childbirth: • a. medication can involve analgesia, anesthesia, and oxytocics; • analgesia relieves pain, • examples tranquilizers, barbiturates and narcotics; • anesthesia, • used late in first stage and while baby is coming out to block sensation or consciousness; • epidural block numbs body from waist down; • oxytosis, • synthetic hormone used to stimulate contractions; • most common, pitocin; • predicting drug effects difficult, depends on type of drug and dosage level. 6A3b natural and prepared childbirth: • aims to reduce pain by decreasing fear through education; • teaches breathing and relaxation strategies; • Lamaze: special breathing techniques to control pushing in final stages. 6A3c. other non-medication techniques: • water birth, • massage • acupuncture. 6A3d. cesarean delivery: • surgical delivery used if baby is turned so bottom would come out first; • or baby is crosswise in uterus; • Also if baby’s head is too large to move through pelvis opening; • Or if complications exist or mother is bleeding vaginally. 6B. Transition from fetus to new born: • stress for baby; • if long delivery, possible decreased oxygen (anoxia); • can lead to brain damage; • usually managed by increased levels of adrenaline and noradrenaline. • after birth, • umbilical cord is cut and baby can breathe independently. • Apgar scale is administered to measure neurological health signs at 1 minute and 5 minutes after birth. • Apgar scale evaluates heart rate, breathing, muscle tone, skin color, and reflex irritability. • If total score is 7-10, baby considered to be in good condition; • if 5, possible problems; • if 3 or less, emergency medical attention is needed. • Low birth weight: less than 3 lbs; • extremely low birth weight: less than 2 lbs. • Premature or preterm: born 3 weeks or more before pregnancy reaches full term (35 or fewer weeks). • Small for date or gestational age: • weight below normal, considering length of pregnancy; • weigh less than 90% of all babies of same gestational age; • may be preterm or full term. • Causes of low birth weight: most but not all are preterm; (66) • Consequences of low-birth weight: • usually have more health and developmental problems than babies of average birth weight. • More likely to have attention deficit, learning disability and breathing problems. • • • • • Kangaroo care: hold baby so skin-to-skin contact; breast feeding on demand; helpful in treating preterm infants; often results in stabilizing heart beat, body temperature and breathing rate. • • • • • Massage therapy: stroking with palms of hands, 3 times daily for about 15 minutes; seems to benefit preterm babies, resulting in increased weight gain, discharge from hospital 3-6 days earlier than without massage therapy. • Bonding: • special component of parent –infant relationship; forming connection, • especially physical bond between parents and children; • extreme form of bonding hypothesis that close contact during first few days of life is required: not supported; • for some infant-mother pairs, • (preterm infants, adolescent mothers, and mothers in disadvantaged circumstances) • early close contact important in establishing improved interaction after leaving hospital. • Postpartum period: • time after child birth; • lasts about 6 weeks until mother’s body has adjusted and returned to nearly pre pregnant state; • mother’s body must adjust physically and psychologically to childbearing process; • family-centered approach can be helpful; • Physical adjustment: • energy levels can be variable; • hormone levels and production (estrogen and progesterone)drop after placenta is delivered and • remain low until ovaries start producing hormones again; • menstrual flow resumes in 4-8 weeks if not breast feeding; • if breast feeding, menstrual flow resumes in several months to a year; • Involution: uterus returns to pre-pregnant size, • usually in 5-6 weeks; • drop in uterus weight from 2-3 lbs to 2-3 ½ ozs. • Conditioning exercises help mother’s body return to pre-pregnant contours and strength; • relaxation exercises also helpful during postpartum period. • Emotional and psychological adjustment: • emotional highs and lows common in postpartum period; • some women’s emotions stabilize faster than others; • about 70% of mothers experience some form of “baby blues” including feeling depressed, anxious and upset; • may last from 2-3 days after birth through 1-2 weeks; • postpartum depression – major depressive episode can occur at about 4 weeks after childbirth; • Mothers have trouble coping with daily tasks; • if not treated, can last for many months; • Fathers also experience postpartum adjustment issues; • may feel baby comes first and receives most of mother’s attention; • may feel baby has taken their place in mother’s affections; • parents should set aside special time for themselves to be together; • helps if father participates in pre-birth classes and • is active participant in caring for the baby. ARE THERE ANY QUESTIONS? • BE SURE TO READ CHAPTER 3 IF YOU HAVE NOT ALREADY DONE SO LIFESPAN CHAPTER 3 DISCUSSION PHYSICAL AND COGNITIVE DEVELOPMENT IN INFANCY LIFESPAN CHAPTER 3 – PHYSICAL AND COGNITIVE DEVELOPMENT IN INFANCY • 1. Physical growth and development in infancy – patterns of growth and development • cephalocaudal patterns – • sequences in which early growth occurs from top to bottom; • physical growth and differentiation of features works from top to bottom; • sensory and motor development also follows this pattern • proximodistal pattern – • growth starts at center of body and moves toward the extremities; • height and weight – • at birth average north American baby 20 inches long and weighs 7 ½ lbs; - • first several days, lose 5-7% of body weight, before adjusting to feeding by sucking, swallowing and digesting; • gain 5-6 oz per week; • double birth weight by 4 mos; and 3x birth weight by age 1; • grow about 1 inch/month; • 1 ½ birth length by age 1. • by 2 years, 26-32 lbs; 32-35 inches tall • Brain – • extensive brain development during infancy and later; • protect baby’s head from falls and other injuries; • shaken baby syndrome – brain swelling and bleeding; • brain development – • does not mature uniformly during infancy; • can be described in terms of sections or lobes – • frontal, parietal, occipital and temporal; - • each section has a left and right counterpart; • 2 halves of brain or hemispheres are not identical in anatomy or function. • lateralization – • specialized function in one or the other hemisphere; • specialization in hemispheres begins at birth; • Example, greater electrical activity in left compared to right side when listening to speech sounds; • language primarily processes on left side • complex functions require cooperation of left and right sides of the brain. • changes in brain cells or neurons – • nerve cells made up of bundles of fibers for handling information; • 2 types of fibers: • dendrites carry information toward the cell body; • axons carry information away from cell body (where nucleus and DNA are); • terminal buttons at ends of axons • release neurotransmitters or chemicals into the synapses or small gaps between neurons; • neurons change in 2 important ways: • a. myelination (covers nerve fibers with fat cells) and • b. increased connectivity (creating new neural pathways; new dendrites develop and increasing numbers of synaptic connections – nearly 2x as many as will eventually be used) • changes in regions of the brain – • dramatic growth in synaptic connections • highest in visual, auditory and prefrontal cortex; • peak of synaptic growth in visual cortex by 4th postnatal month; • peak in hearing and language areas similar, though somewhat later; • peak in prefrontal cortex area (for higher level thinking)about 1 year; • mid to late adolescence achieve adult density achieved; • peak myelination in visual cortex complete in about 6 months; • peak myelination in hearing area not complete until age 4 or 5; • early experiences and the brain – • before birth genes determine basic nerve connections; • after birth, environmental experiences determines brain development. • sleep – average newborn sleeps 16-17 hours/day total; wide variability in how time spread throughout the day; by 1 month sleep longer at night; by 4 months, closer to adult sleeping patterns; • REM sleep – greater amount of time; rapid eye movement sleep; about ½ of infant sleep time; by 3 mos, REM percentage decrease to 40%; • why? may provide added self-stimulation; may promote brain development in infancy; • • • • SIDS – sudden infant death syndrome; infant stops breathing, usually at night; dies without apparent cause. • American Academy of Pediatrics recommends infants sleep on back; • why? • sleeping on stomach impairs arousal from sleep; • restricts ability to swallow; • increased risk if exposed to passive cigarette smoke or sleep on soft bed Nutrition• breast vs bottle feeding – • 1st 4-6 mos human milk or alternative formula is main source of nutrients and energy; • growing consensus that breast feeding is best; Breast Feeding Benefits • - appropriate weight gain; • lower risk of childhood obesity; • prevention or reduction of diarrhea, respiratory infections, bacterial or urinary tract infections, otitis media (middle ear infection); • denser bones in childhood and adulthood; • decreased risk of childhood cancer and decreased risk of breast cancer in mothers; • when should not breast feed? • 1)mom infected with AIDS or other infectious disease; • 2)mom has active tuberculosis; • 3)mom taking drugs not safe for baby. • nutritional needs: • recommend infants consume 50 cal/day per lb of body weight; • early nutrition important; • Family Support/Healthy Start Program in Hawaii good example of helpful services for families of newborns at risk for developmental problems; Motor development – how do infants develop motor skills; which skills develop at what time: • dynamic systems theory – • assemble motor skills for perceiving and acting; perception and action coordinated; • to develop skills, infants perceive something in environment that motivates them to act; • use perceptions to fine tune movements; • motor skills are solutions to goals; - new behavior results from converging factors • • • • a. nervous system development, b. body’s physical properties, c. possibilities for movement; d. goal motivated to reach, environmental support for skill; • e. infant change movement patterns to fit new task by exploring and selecting possible movement patterns reflexes • • • • built in reactions to environmental signals; genetically carried survival responses; automatic and involuntary; allow adaptive response before opportunity to learn; • example, if immersed in water, automatically hold breath and constrict throat; other reflexes • rooting and sucking – • if stroke cheek or touch side of mouth, turn toward side touched or stroked; • find something to suck; • sucking – occurs if object placed in baby’s mouth; • Moro reflex – • startle response to sudden intense noise or movement; • arch back, throw back head, fling out arms and legs then quickly close arms and legs; • possible way of grabbing for support while falling; • some reflexes persist throughout life – • cough, sneeze, blink, shiver, yawn; • some reflexes incorporated into more complex voluntary behaviors later • example: (grasping reflex)occurs when something touches infant palm; • by end of 3rd month, action more voluntary, smoother; manipulating and exploring. Gross Motor Skills • involve large muscle activities; • moving arms and legs; • newborns cannot control posture voluntarily; after few weeks, can hold head up; • soon lift head while on stomach; • 2 mos – sit while supported in lap; • 6 mos; sit up independently; • 8 mos – pull self to standing position while holding on to support; • 10-12 mos • can stand alone; • to walk upright, balance on one leg while shifting other forward; • shift weight from one leg to the other; • must learn places and surfaces safe for crawling and walking; • to learn where safe to crawl and walk, have to integrate perceptual information and motor skills • First year: milestones and variations (chart on page 86) timing of reaching milestones can vary by 2-4 months; • some babies never crawl; Second year gross motor skills • • • • • • • • pull a toy attached to string; use hands and legs to climb steps; walk quickly; run a short distance; balance on feet while squatting; walk backward; stand and throw a ball; jump in place; Fine motor skills • grasp a toy; • use spoon, • button shirt; • reaching and grasping significant achievement; • first reach by moving shoulders and swing arm around; • later, move wrist, rotate hands; • must coordinate thumb and forefinger motions; • perceptual-motor coordination necessary for grasping; • 4 mos – rely more on touch to grasp; • 8 mos – use vision more often as cue; • experience influences grasping skills: • infants who had practice with “sticky mittens” learned grasping skills sooner. • exercising gross motor skills and fine motor skills important and helpful. EXPLORING SENSORY AND PERCEPTUAL DEVELOPMENT • sensation: info interacts with sensory receptors – eyes, ears tongue, nostrils and skin • perception: interpreting what is sensed. • ecological view (Eleanor and James Gibson): we directly perceive information in the world around us. perception allows contact with environment and adapting to it. • Robert Fantz: found babies look at different things for different lengths of time. • Babies in looking chamber; • 2 visual displays (p. 90) above babies head; • experiments used peephole to watch babies’ eyes; • babies 2 days of age preferred patterned stimuli to plainly colored discs. Habituation and dishabituation • decreased and increased response to stimuli respectively; • present stimulus a number of times; • if decreased response to stimulus, indicates lower interest in it; • measures of habituation: sucking, heart rate breathing rate. • High amplitude sucking: • nonnutritive nipple connected to sound generator; each sucking act causes a sound; habituate to same sounds; experimenter can change sounds; babies show ability to discriminate between the sounds. • Other methods: orienting response (turn head toward sight or sound); tracking (eye movements following moving objects. VISUAL PERCEPTION • • • • NEWBORN VISION: 20/600; 5 mos: 20/100; 1 year: approximately same as normal (20/20) adult vision. Color vision • birth - distinguish green and red; • 2 mos – all color receptors active at normal levels of sensitivity. PERCEIVING PATTERNS • 2-3 week-old infants prefer patterns to plain stimuli; • 2 mos – scans more facial details than 1 mo. DEPTH PERCEPTION • Eleanor Gibson and James Walk: • develop visual cliff with drop-off covered with glass; • 6-12 mos on edge of visual cliff; • mothers tried to coax babies to crawl onto glass; - • babies just starting to crawl would cross; • after a few weeks, would not cross; • infants can perceive depth by about 3-4 mos and • usually refuse to cross drop-off OTHER SENSES • HEARING • can hear during last 2 mos before birth; • babies whose moms read Cat in the Hat to them before birth gave different response to Cat in the Hat reading after birth compared to King, Mice and Cheese (different reading pace and emphasis with voice tones). • Changes in hearing during infancy – perception loudness pitch and location: • 1)immediately after birth can’t hear soft sounds as well as adults; • 2)newborns less sensitive to changes in pitch (frequency such as soprano or bass tones) compared to adults; - • at 2 years, • improved pitch distinction; • 3)newborns can determine general sound location; • by 6 mos much better at determining specific locations • TOUCH AND PAIN • touch stimulates reflexes (rooting and sucking); • pain – respond to circumcision (no anesthesia) with intense crying; • recover quickly (normal eating and social responses) • TASTE – • saccharin in amniotic fluid of near-term fetus resulted in increased swallowing; • different facial expression to sweet, salt and bitter solutions (pictures on page 93) • INTERMODAL PERCEPTION • Integrate information from 2 or more senses; newborns turn head at sound of rattle. COGNITIVE DEVELOPMENT • Piaget’s theory: • adaptation – adjusting to new environmental demands and actively constructing mental world; • schemes – actions or mental representations for organizing knowledge; • infants actively use physical responses (sucking, grasping); • toddlers and older children use mental schemes (cognitive activities) for organizing experiences. • assimilation – use existing schemes to handle new information; • accommodation – adjust existing schemes to handle new information; • organization – grouping isolated behaviors and thoughts into higher order systems. • EQUILIBRATION AND STAGES OF DEVELOPMENT – process by which make shift from one stage of development to the next; 4 stages of development – first stage is sensorimotor stage (birth to 2 years); 6 SENSORIMOTOR SUBSTAGES – • 1)simple reflexes: birth to 1 mo; • sensation and action coordinated using reflexive behaviors; • 2)first habits and primary circular reactions – • 1-4 mos; • coordinates sensations and 2 schemes, habits and primary circular reactions; • habit is scheme based on reflex separated from triggering stimulus; (sucking) • primary circular reactions are repetitive actions based on trying to reproduce event first occurring by chance; (kicking mobile) • stereotyped and repeated the same way each time; • • • • • • 3)secondary circular reactions; 4-8 mos; more object oriented; repeated because of consequences; example: shake rattle to reproduce sound; some imitation of behavior by others; • • • • • • 4) coordinated secondary circular reactions; 8-12 mos; coordinates vision and touch; eye and hand; actions more outwardly-directed; coordinates actions and intentions; • • • • 5)tertiary circular reactions – beginnings of novelty and curiosity; 12-18 mos; interested in properties of objects and things they can do to objects (fall, spin, slide, hit another object); • purposely explore new possibilities of objects and experiences; • 6) internalized schemes – • 18-24 mos; use primitive symbols (internal sensory images or words that represent concrete objects; • can think about concrete objects and events without actually seeing or touching them; OBJECT PERMANENCE • Understanding that objects continue to exist even though cannot see, touch or hear them; • EVALUATING OBJECT PERMANENCE – some modifications of Piaget’s ideas; • A-not-B or AB error (playing hide toy under the blanket game); • may be memory or motivation problem rather than lack of cognitive ability; • some cognitive abilities can be demonstrated earlier than Piaget thought, • such as object permanence • LEARNING, REMEMBERING AND CONCEPTUALIZING • CONDITIONING – • Skinner’s operant conditioning; • behavior’s consequences change probability that behavior will occur in the future; • infants can learn using operant conditioning, especially perceptual skills; • infant suck faster on nipple if sucking following by interesting visual display musical sounds, or human voice; • Rovee-Collier showed 2 ½ -mo-old infant whose foot was tied to a mobile and who learned to kick to make the mobile move • later kicked even when foot not tied to mobile; ATTENTION • • • • focus mental resources on select information; newborn can detect contours of objects; older babies scan more thoroughly; attention is influenced by novelty and habituation; • if object is familiar, attention is shorter and more vulnerable to distraction; • joint attention – • 2 individuals (such as baby and parent or caregiver) focus on same object or event; • • • • • • requires 1)ability to track someone else’s attention; 2)reciprocal interaction; emerging forms at 7-8 mos; skills more developed at 10-11 mos; by 12 mos, infant can direct adult attention; • increases infant’s ability to learn from other people responses, such as language. IMITATION • Meltzoff believes infants’ imitation ability is biologically-based; • observed some imitation by newborns; • not 100% accepted; • Meltzoff also described deferred imitation in which babies demonstrate behaviors they observed as much as 24 hours earlier; • MEMORY – retention of information over time; • Rovee-Collier concluded memory skills demonstrated by infants as young as 1 ½ -2 years; • disagreement whether implicit (memory without conscious recollection; • performed automatically)or explicit (conscious memory of facts and experiences)memory. • infantile or childhood amnesia – • difficulty remembering events during first 1-3 years of life; CONCEPT FORMATION AND CATEGORIZATION • concepts – ideas about what categories represent; • Categories - groups of objects and events and characteristics based on common properties; • 7-9 mos use conceptual categories characterized by perceptual variability; • first concepts broad and general; • gradually differentiated. LANGUAGE DEVELOPMENT • language is form of communication based on systems of symbols; • consists of words used by a group and rules for combining and varying them; • infinite generativity – ability to reproduce endless number of meaningful sentences using limited set of rules and words; • • • • • crying – signals distress and other meanings; cooing – first observed at 1-2 mos; gurgling sounds from back of throat; usually signal pleasure; babbling – strings of consonant-vowel combinations; • gestures – showing or pointing at objects or people; first observed about 8-12 mos; a wave bye-bye, nod yes. • recognizing language sounds – • before can make language sounds, • can recognize differences in sounds; • until 6 mos, recognize sound differences regardless of language source; • gradually lose ability to (or interest in) recognizing differences in languages other than the one they ear most often. • first words – usually observed at 8-12 mos; • indicates first understanding of words; • first spoken words at 10-15 mos; • average 13 mos; • first words usually name important people, familiar animals; • vehicles, toys, food, body parts, clothes, household items, greetings; • receptive vocabulary – develop faster than expressive or spoken vocabulary; • expressive vocabulary increases very quickly after first spoken words; • vocabulary spurt. • 2-word utterances – 18-24 mos; convey meaning with 2 words plus gestures, tone of voice and using context; • omit some parts of speech; • succinct and telegraphic; • omit grammatical markers such as articles, auxiliary verbs and connective words. BIOLOGICAL AND ENVIRONMENTAL INFLUENCES • spoken language required certain vocal structures and nervous system capabilities; • 2 areas of brain important (Broca and Wernicke) in left hemisphere; • Noam Chomsky suggested language acquisition device (biological readiness to learn language; • not referring to any specific biological or anatomical structure; environmental influence • behaviorist view explaining language as chains of reinforced verbal behaviors, • Problems with strict behaviorist view • 1)does not explain novel sentences; • 2) children learn syntax or grammar of own language without reinforcement; • experiences, particular language learned, context of language influence language acquisition; • support and involvement of caregivers and teachers influence language behavior; • interactive view of language learning – • learn specific languages in specific contexts; • child’s vocabulary links to family socioeconomic status and speech parents direct toward their children; • child-directed speech – spoken using higherpitch with simple words and sentences; • captures attention and maintains communication; • includes “baby-talk”; • other adult strategies: • 1)recasting – rephrasing something child says; allows indicating interest and elaborating interest; • 2)expanding – restating in linguistically sophisticated from what child says; • 3)labeling – identifying the nature of objects and experiences; original word game; • Strategies used best to guide language learning instead of overloading; • encouragement is better than drill and practice; IDEAS TO HELP PARENT GUIDE LANGUAGE LEARNING • • • • infants – be active conversational partner; talk as if infant understands; use language style comfortable to individual parent; • • • • • • toddlers – continue active conversational partner; remember to listen; use comfortable language style; consider expanding child’s language abilities; adjust to child’s idiosyncrasies; • • • • • • interactionist view – biology and environment both important; provide rich verbal environment; provide opportunities for conversation; pay attention and listen; read to children and label things and events in environment
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