Section 1 - Nature and Nurture: The Enduring Developmental Issue
MAIN IDEA QUESTION
How do psychologists study the degree to which development is an interaction of hereditary and environmental factors?
VOCABULARY
developmental psychology - the branch of psychology that studies the patterns of growth and change that occur throughout life
nature-nurture issue - the issue of the degree to which environment and heredity influence behavior
identical twins - twins who are genetically identical
cross-sectional research - a research method that compares people of different ages at the same point in time
longitudinal study - a research method that investigates behavior as participants age
sequential research - a research method that combines cross-sectional and longitudinal research by considering a number of different age groups and examining them at several points in time
How many bald, six-foot-six, 250-pound volunteer firefighters in New Jersey wear droopy mustaches, aviator-style glasses, and a key ring on the right side of the belt? The answer is two: Gerald Levey and Mark Newman. They are twins who were separated at birth. Each twin did not even know the other existed until they were reunited - in a fire station - by a fellow firefighter who knew Newman and was startled to see his double, Levey, at a firefighter's convention.
The lives of the twins, although separate, took remarkably similar paths. Levey went to college and studied forestry; Newman planned to study forestry in college but instead took a job trimming trees. Both had jobs in supermarkets. One had a job installing sprinkler systems; the other installed fire alarms.
Both men are unmarried and find the same kind of woman - "tall, slender, long hair" - attractive. They share similar hobbies and enjoy hunting, fishing, going to the beach, and watching old John Wayne movies and professional wrestling. Both like Chinese food and drink the same brand of beer. Their mannerisms are also similar - for example, each one throws his head back when he laughs. And, of course, there is one more thing: They share a passion for fighting fires.
The similarities we see in twins separated at birth raise one of the fundamental questions posed by developmental psychology. The question is - How can we distinguish between the environmental causes of behavior (the influence of parents, siblings, family, friends, schooling, nutrition, and all other situations to which a child is exposed) and hereditary causes (those based on an individual's genetic makeup that influence growth and development throughout life)? This question embodies the nature-nurture issue. Nature refers to hereditary factors while nurture refers to environmental factors.
~Psychologists today agree that both interact to produce specific developmental patterns and outcomes. The question has evolved into this: How and to what degree do environment and heredity produce their effects? There are development theories which support both to varying degrees.
~Some theories stress the role of heredity and maturation - the unfloding of biologically predetermined patterns of behavior - in producing developmental change. Maturation can be seen in the development of sex characteristics (such as breasts and body hair). Developmental psychologists study the work of behavioral geneticists and evolutionary biologists. Other theories stress the role of learning, emphasizing the environment's role in development.
~Despite their differences, there are agreements. They agree that genetic factors provide both potential and limits for traits and abilities to emerge. The following are characteristics most affected by heredity. They are not entirely affected, as the environment may play a role.
Physical characteristics - height / weight / obesity / tone of voice / blood pressure / tooth decay / athletic ability / firmness of handshake / age of death / activity level
Intellectual characteristics - memory / intelligence / age of language acquisition / reading disability / mental retardation
Emotional characteristics and disorders - shyness / extraversion / emotionality / neuroticism / schizophrenia / anxiety / alcoholism
~Both sides agree on potential of genetics. EX: If Albert Einstein had received no intellectual stimulation as a child and had not been sent to school, it is unlikely that he would ahve reached his genetic potential. EX: Baseball star Derek Jeter would have been unlikely to display such physical skill if he had not been raised in an environment that nurtured his innate talent and gave him the opportunity to train and perfect his natural abilities.
DETERMINING THE RELATIVE INFLUENCE OF NATURE AND NURTURE
In determining the influence of both, researchers have taken different approaches. In one approach, researchers can experimentally control the genetic makeup of laboratory animals by carefully breeding them for specific traits. Researchers are then able to study animals with identical genetic backgrounds placed in varying environments
~Human twins serve as another important source of information. If identical twins display different patterns of development, those differences have to be attributed to variations in the environment in which the twins were raised. The most useful data comes from identical twins who were separated at birth by sets of adoptive parents and raised apart in differing environments.
~Studies of nontwin siblings who are raised in totally different environments also shed some light on the issue. With similar genetic backgrounds, siblings who show similarities as adults provide strong evidence for the importance of heredity.
~In reverse, researchers may examine people raised in similar environments who have totally dissimilar genetic backgrounds. EX: Two adopted children who have different genetic backgrounds and raised in the same family provides evidence for environmental influence.
DEVELOPMENTAL RESEARCH TECHNIQUES
The most frequently used method is cross-sectional research, which compares people of different at ages at the same point in time. This provides information about differences in development between different age groups. EX: If we were interested in finding intellectual ability in adulthood, we might compare a sample of 25-, 45-, and 65-year-olds who all take the same IQ test. We can then find the average score for each age group. The limit of this approach is that we cannot determine that differences in scores is due to age differences alone. It may reflect the educational attainment of the people represented.
~The second major research strategy is a longitudinal study. Longitudinal research traces the behavior of one or more participants as the participants age. These studies assess change in behavior over time, whereas cross-sectional examines differences among groups of people. Using a longitudinal study to assess the same question of intelligence during adulthood; EX: We give an IQ test to a group of 25-year-olds, then retest them at age 45 and again at 65. From this, we can clearly see how individuals develop. The problem with this research is it requires an enormous expenditure of time as the researcher waits for the participants to get older. Subjects may drop out, move away, or even die as the research continues.
~To make up for the disadvantages of cross-sectional and longitudinal studies, investigators have devised an alternative strategy known as sequential research - an approach which combines cross-sectional with longitudinal by studying different age groups at several points in time. EX: Researchers might examine a group of 3-, 5-, and 7-year-olds every six months for a period of several years.
Section 2 - Prenatal Development: Conception to Birth
MAIN IDEA QUESTIONS
What is the nature of development before birth?
What factors affect a child during the mother's pregnancy?
VOCABULARY
chromosomes - rod-shaped structures that contain all basic hereditary information
genes - the parts of the chromosomes through which genetic information is transmitted
zygote - the new cell formed by the union of an egg and sperm
embryo - a developed zygote that has a heart, a brain, and other organs
fetus - a developing individual from eight weeks after conception until birth
age of viability - the point at which a fetus can survive if born prematurely
teratogens - environmental agents such as a drug, chemical, virus, or other factor that produce a birth defect
THE BASICS OF GENETICS
The one-cell entity established at conception contains 23 pairs of chromosomes. One member of each pair is from the mother, and the other is from the father. Each chromosome contains thousands of genes. Genes produce each person's particular characteristics. Composed of sequences of DNA molecules, genes are the biological equivalent of "software" that programs the future development of all parts of the body's hardware. Humans have some 25,000 different genes.
~Some genes control the heart, circulatory system, brain, lungs, and so forth; others shape the characteristics that make each human unique, such as facial configuration, height, and eye color. The child's sex is determined by a particular set of chromosomes, inheriting an X from the mother and either an X or Y from the father. XX = female, XY = male.
~Geneticists have discovered that genes are partially responsible for a wide variety of personal charcteristics, including cognitive abilities, personality traits, and psychological disorders. Few of these characteristics are determined by single genes. Most traits result from a combination of multiple genes that operate together with environmental influences.
The Human Genome Project
In 2001, scientists were able to map the specific location and sequence of every human gene as part of the massive Human Genome Project. The success of the project started a revolution in health care because scientists can identify particular genes responsible for genetically caused disorders. It has already led to the identification of risk factors in children, and the development of new treatments for physical and psychological disorders.
EX: In gene therapy, genes are injected to correct particular diseases directly into a patient's bloodstream. When the gene arrives at the location of the problem, or potential problem, it leads the body to produce chemicals that can alleviate the danger. In other cases, genes are inserted which replace missing or defective cells.
~The long-term success of gene therapy is unknown, and the number of real diseases it can treat today is still limited. Some recipients of gene therapy have relapsed. Still, the potential uses are growing rapidly. Such disorders as AIDS, cancer, rheumatoid arthritis, and nuclear degeneration are strong candidates for the procedure.
THE EARLIEST DEVELOPMENT
When an egg becomes fertilized by the sperm, the resulting one-cell entity, called a zygote, immediately begins to develop. It starts out as a microscopic speck, which after 3 days, increases to around 32 cells during the germinal period. Two weeks after conception, the development enters the embryonic period, which lasts from week 2 through week 8; he or she is now called an embryo. The embryo grows 10,000 times larger by four weeks, at which point it develops a beating heart, a brain, an intestinal tract, and a number of organs. By week 8, the embryo is about an inch long and has discernible arms, legs, and a face.
~From week 8 until birth is known as the fetal period, and the developing individual is called a fetus. At 16 to 18 weeks, its movements become strong enough for the mother to notice them, while hair and facial features become similar to what the child will have at birth. A lifetime's worth of brain neurons are produced, and the major organs begin functioning - though it still can't survive outside of the womb. If the infant were born prematurely around 24 weeks, it could open and close its eyes; suck; cry; look up, down, and around; and even grasp objects in its hands.
~The fetus continues to grow past 24 weeks, developing fatty deposits under the skin, gaining weight. The fetus reaches the age of viability in which it could survive prematurely at about 22 weeks. At 28 weeks, the fetus weighs less than 3 pounds and may be capable of learning.
EX: One study found that infants of mothers who had repeatedly read aloud The Cat in the Hat by Dr. Seuss before the infants' birth preferred the sound of that particular story to other stories after they were born.
~Before birth, fetuses go through sensitive periods where they are particularly sensitive to certain kinds of stimuli. EX: Drugs. If they are exposed to drugs during these periods, the impact will be significant. Sensitive periods can also occur after birth.
~At the end of the normal 38-week pregnancy, the fetus typically weighs 7 pounds and is about 20 inches in length. Preterm infants - those born before 38 weeks - are not fully developed and are more susceptible to illness, future problems, and even death. Those born before week 30 have relatively poor prospects of health... often times with a 50-50 chance of survival.
Genetic Influences on the Fetus
Normal development through 38 weeks is the case 95-98% of the time with all pregnancies. In the remaining 2-5% of cases, children are born with serious birth defects. A major cause of such defects is faulty genes or chromosomes. Here are some of the common genetic and chromosomal difficulties;
~Phenylketonuria (PKU) - child cannot produce an enzyme required for development, resulting in the accumulation of poisons which cause mental retardation
~Sickle-cell anemia - affects 10% of the African American population. It causes abnormally shaped red blood cells, causing episodes of pain, yellowish eyes, stunted growth, and vision problems.
~Tay-Sachs disease - most often found in Jews of Eastern European ancestry, this is a disease which does not allow the body to break down fat, usually causing the child to die by age 3 or 4.
~Down syndrome - when a zygote receives an extra chromosome, resulting in retardation
Prenatal Environmental Influences
Environmental influences can also affect the fetus. Some of the more profound consequences are brought about by teratogens - drugs, chemicals, viruses or other factors that produce a birth defect. Here are some of the major environmental influences;
~Mother's nutrition - poor nourishment leads to higher susceptibility to dieases and poor development, which can lead to poor mental development
~Mother's illness - diseases such as rubella, AIDS, syphilis, diabetes, and high blood pressure may adversely effect the fetus. AIDS can be passed to the child pre-birth, or by breastfeeding after birth.
~Mother's emotional state - anxiety and tension in the final months of birth can lead to irritable infants who sleep and eat poorly... this is because the autonomic nervous system of the fetus becomes sensitive to chemical changes produced by the mother's emotional state
~Mother's use of drugs - babies may become addicted to drugs the mother is taking. Babies go through withdrawal symptoms after birth and often suffer physical and mental impairment. Even legal drugs can have a tragic effect.
~Alcohol - 1 out of every 750 infants is born with fetal alcohol syndrome, resulting in below-average intelligence, growth delays, and facial deformities
~Nicotine use - smoking can lead to miscarriage and infant death, and other consequences can lead to negative consequences that last a lifetime
Although we have been discussing genetic and environmental factors separately, neither works alone.
Alternative Paths to Conception
In some cases, conception represents a major challenge for some couples. Infertility can be the result of a male producing too few sperm. In other cases, it is due to the advanced age of the parents, use of drugs, or previous cases of sexually transmitted disease. Some remedies have been developed by scientists;
~in vitro fertilization (IVF) - eggs are removed from a woman's ovaries and a man's sperm is used to fertilize the eggs in a laboratory
~gamete intrafallopian transfer (GIFT) and zygote intrafallopian transfer (ZIFT) - a fertilized egg is implanted in a woman's fallopian tubes... in some cases the egg is implanted in a surrogate mother - a woman who agrees to carry the child to term.
Section 3 - Infancy and Childhood
MAIN IDEA QUESTIONS
What are the major competencies of newborns?
What are the milestones of physical and social development during childhood?
How does cognitive development proceed during childhood?
VOCABULARY
neonate - a newborn child
reflexes - unlearned, involuntary responses that occur automatically in the presence of certain stimuli
habituation - the decrease in the response to a stimulus that occurs after repeated presentations of the same stimulus
attachment - the positive emotional bond that develops between a child and a particular individual
authoritarian parents - parents who are rigid and punitive and value unquestioning obedience from their children
permissive parents - parents who give their children relaxed or inconsistent direction and, although they are warm, require little of them
authoritative parents - parents who are firm, set clear limits, reason with their children, and explain things to them
uninvolved parents - parents who show little interest in their children and are emotionally detached
temperament - basic, innate disposition
psychosocial development - development of individuals' interactions and understanding of each other and of their knowledge and understanding of themselves and members of society
trust-versus-mistrust stage - according to Erikson, the first stage of psychosocial development, occurring from birth to age 1 1/2 years, during which time infants develop feelings of trust or lack of trust
autonomy-versus-shame-and-doubt stage - the period during which, according to Erikson, toddlers (ages 1 1/2 to 3 years) develop independence and autonomy if exploration and freedom are encouraged or shame and self-doubt if they are restricted and overprotected
initiative-versus-guilt stage - according to Erikson, the period during which children ages 3 to 6 years experience conflict between independence of action and the sometimes negative results of that action
industry-versus-inferiority stage - according to Erikson, the last stage of childhood, during which children age 6 to 12 years may develop positive social interactions with others or may feel inadequate and become less sociable
cognitive development - the process by which a child's understanding of the world changes as a function of age and experience
sensorimotor stage - according to Piaget, the stage from birth to 2 years, during which a child has little competence in representing the environment by using images, language, or other symbols
object permanence - the awareness that objects - and people - continue to exist even if they are out of sight
preoperational stage - according to Piaget, the period from 2 to 7 years of age that is characterized by language development
egocentric thought - a way of thinking in which a child views the world entirely from his or her own perspective
principle of conservation - the knowledge that quantity is unrelated to the arrangement and physical appearance of objects
concrete operational stage - according to Piaget, the period from 7 to 12 years of age that is characterized by logical thought and a loss of egocentrism
formal operational stage - according to Piaget, the period from age 12 to adulthood that is characterized by abstract thought
information processing - the way in which people take in, use, and store information
metacognition - an awareness and understanding of one's own cognitive processes
zone of proximal development (ZPD) - according to Vygotsky, the level at which a child can almost, but not fully, comprehend or perform a task on his or her own
Called a neonate, a newborn arrives in the world in a form that hardly meets the standards of beauty against which we typically measure babies. Yet ask any parents; Nothing is more beautiful or exciting than the first glimpse of their new born.
THE EXTRAORDINARY NEWBORN
The trip through the mother's birth canal may squeeze the incompletely formed bones of the skull together and squashed the nose into the head. The skin secretes vernix, a white greasy covering, for protection before birth, and the baby may have lanugo, a soft fuzz, over the entire body for a similar purpose. The infant's eyelids may be puffy with an accumulation of fluids because of the upside-down position during birth. These features change during the first two weeks of life as the neonate takes on a more familiar appearance. The neonate develops impressive capabilities that grow at an astounding rate over the next couple of months.
Reflexes
A neonate is born with a number of reflexes - unlearned, involuntary responses that occur automatically in the presence of certain stimuli.
rooting reflex - turn their heads towards things that touch their cheek
sucking reflex - prompts infants to suck things that touch their lips
gag reflex - clear the throat
startle reflex - movements in response to a sudden noise
Babinski reflex - a baby's toes fan out when the outer edge of the sole of the foot is stroked
~These primitive reflexes are lost after the first few months and are replaced with more complex and organized behavior. The ability to move independently grows enormously during the first year of life. Fine-muscle movements become increasingly sophisticated.
3 months - rolling over, grasping rattle
6 months - sitting without support
7 months - standing while holding on
8 months - grasping with thumb and finger
11.5 months - standing alone well
12 months - walking well
15 months - building tower of two cubes
16.5 months - walking up steps
24 months - jumping in place
Development of the Senses: Taking in the World
Although their eyes have a limited ability to focus on objects that are not within a seven- to eight-inch distance from the face, neonates can follow objects moving within their field of vision. They show rudiments of depth perception as they raise their hands up when objects move toward their face.
Infants who see a novel stimulus typically pay close attention to it; as a consequence, their heart rates increase. But if they repeatedly see the same stimulus, their attention to it decrease, as indicated by a return to a slower heart rate. This phenomenon is known as habituation.
~At birth, babies prefer patterns with contours and edges over less distinct patterns, indicating that they can respond to the configuration of stimuli. Furthermore, they are aware of size constancy (objects stay the same size even though the image of them changes with distance).
~Neonates can discriminate facial expressions, and even imitate them. They can react to the facial expressions and moods of their caregivers. This capability provides the foundation for social interaction skills in children.
~By the end of their first month, babies can distinguish some colors from others; after four months they can focus on near or far objects and are able to recognize two- or three-dimensional objects. Sensitivity to visual stimuli becomes three to four times greater at 1 year of age after birth.
~Newborns can distinguish different sounds to the point of being able to recognize their mothers' voices at the age of 3 days. After a couple days of age, they can already distinguish between their native tongue and foreign languages. They can recognize tastes and smells at a very early age. There seems to be a built-in sweet tooth; they prefer liquids that have been sweetened with sugar over their unsweetened counterparts.
INFANCY THROUGH CHILDHOOD
EX: A 10-month old child at the local day-care center suddenly learns how to undo the velcro on his winter hat. He begins to take his hat off at will. Soon, the other children at the day-care follow his lead.
This child has asserted his personality. Throughout the remainder of childhood until age 11 or 12, children develop physically, socially, and cognitively in extraordinary ways.
Physical Development
Physical growth provides the most obvious sign of development during this period. Children usually triple their birth weight in their first year of life. From age 3 to age 13, growth averages a gain of about 5 pounds and 3 inches a year. Furhtermore, the relationship of the size of various body parts to one another changes dramatically as children age. EX: Head of a fetus is disproportionately large, but the body fills out after birth.
Average height/weight by age 20; Boys - 5'11"/155 lbs, Girls - 5'3" / 127 lbs
Development of Social Behavior: Taking on the World
The nature of a child's early social development provides the foundation for social relationships that will last a lifetime. Attachment is the positive emotional bond that develops between a child and a particular individual and is the most important form of social development that occurs during infancy. Developmental psychologists have suggested that human attachment grows through the responsiveness of infants' caregivers to the signals the babies provide, such as crying, smiling, reaching, and clinging. The greater the responsiveness to the child's signals, the more attached the child becomes. Full attachment develops when the infant plays as critical and active of a role as the caregiver in the formation of the bond. Infants who respond positively to a caregiver produce more positive behavior on the caregiver's part.
Assessing Attachment. There is a quick and direct way to measure attachment. Developed by Mary Ainsworth, the Ainsworth strange situation consists of a sequence of events involving a child and (typically) his or her mother. Initially, the mother and baby enter an unfamiliar room, and the mother permits the baby to explore while she sits down. An adult stranger then enters the room; after this the mother leaves. The mother returns and the stranger leaves. The mother once again leaves the baby alone, and the stranger returns. Finally, the stranger leaves, and the mother returns.
~Babies' reactions to this experimental situation vary drastically, depending on their degree of attachment to the mother (according to Ainsworth). One-year-old children who are securely attached employ the mother as a home base; they explore independently but return to her occasionally. When she leaves, they exhibit distress, and they go to her when she returns. Avoidant children do not cry when the mother leaves, and they seem to avoid her when she returns, as if indifferent to her. Ambivalent children display anxiety before they are separated and are upset when the mother leaves, but they may show ambivalent reactions to her return, such as seeking close contact but simultaneously kicking or hitting her. A fourth reaction is disorganized-disoriented; these children show inconsistent and often contradictory behavior.
~The nature of attachment has far-reaching consequences for later development. Children who are securely attached to their mothers tend to be more socially and emotionally competent than are their less securely attached peers. They show fewer psychological difficulties and tend to have more successful romantic relationships. While secure attachment does not guarantee good adjustment later in life, conversely, children who lack secure attachment do not always have difficulties later in life.
The Father's Role. More recent research has highlighted the father's role in parenting. The number of fathers who are primary caregivers has grown significantly, with fathers playing an increasingly important role in their children's lives. In 13% of families, the father is the one who stays home to care for preschoolers. Fathers play with their children in different ways than their mothers. Fathers engage in more physical, rough-and-tumble sorts of activities, whereas mothers play more verbal and traditional games, such as peekaboo. Father and mother attachments to children can be similar, and children can form multiple attachments.
Social Relationships with Peers. By the time they are 2 years old, children become less dependent on their parents, more self-reliant, and increasingly prefer to play with friends. Even when sitting side-by-side, two year olds pay more attention to toys than to one another when playing. As they develop more, they interact more. Cultural factors may also be a factor. EX: Korean-American children engage in less pretend play than thei Anglo-American counterparts. Once children reach school age, they participate in games and activities with teams and rigid rules. This helps them become socially competent.
In short, social interaction helps children interpret the meaning of others' behavior. They learn physical and emotional self-control: They learn to avoid hitting a playmate who beats them at a game. They learn to be polite and control their facial expressions and emotional displays.
The Consequences of Child Care Outside the Home. Almost 30% of preschool children whose mothers work outside the home spend their days in child-care centers. By the age of 6 months, more than two-thirds of infants are cared for by people other than their mothers for part of the day. Do these arrangements outside the home benefit a child's development? If the programs are of high quality, they can. Research shwos that children in high-quality day care arrangements may not only do as well as their peers who saty home with parents, they may actually do better. They generally become more considerate and sociable, and they interact more positively with teachers. They may also be more compliant and regulate their behavior more effectively. Often times, the environment of high-quality day care is more intellectually stimulating. This can lead to higher IQ scores and better language development. In fact, children in care centers sometimes are found to score higher on tests of cognitive abilities than those who are cared for by their mothers or sitters.
On the negative side, children may feel insecure after placement in low-quality child care, or in multiple care settings. Infants in outside care more than 20 hours per week show less secure attachment to their mothers. They may also suffer from a reduced ability to work independently and manage their time effectively when they reach elementary school.
~The key to success for nonparental child care is its quality.
Parenting Styles and Social Development. Parents' child-rearing practices are critical in shaping their children's social competence. Four main categories describe different parenting styles; authoritarian, permissive, authoritative, uninvolved.
Stormy Adolescence: Myth Or Reality?
Does puberty invariably foreshadow a stormy, rebellious period of adolescence?
~Research now shows that this characterization is largely a myth, that most young people pass through adolescence without appreciable turmoil in their lives, and that parents speak easily - and fairly often - with their children about a variety of topics.
~Adolescence is not completely calm. In most families, the amount of arguing and bickering clearly rises. Most young teenagers experience tension between their attempts to become independent from their parents and their actual dependence on them. They may experiment with a range of behaviors and flirt with a variety of activities that their parents, and even society as a whole, find objectionable. For most families, such tension declines around middle adolescence - around age 15 or 16 - and eventually decline around age 18.
~One reason for the increase in discord during adolescence appears to be protracted periods in which children stay at home with their parents. In prior historical periods, and some non-Western cultures today, children leave home immediately after puberty and are considered adults. Today, sexually mature adolescents may spend as much as seven or eight years with their parents.
~Current social trends show a significant number of young adults - known as boomerang children - return to live with their parents, typically for economic reasons, after leaving home for some period. Although some parents welcome the return of their children, others are less sympathetic, which opens the way to conflict.
~Another source of strife with parents is the way adolescents think. Adolescence fosters adolescent egocentrism, a state of self-absorption in which a teenager views the world from his or her own point of view. It leads adolescents to be highly critical of authority figures, unwilling to accept criticism, and quick to fault others. It also makes them believe they are the center of everyone else's attention, which leads to self-consciousness. They develop personal fables, the belief that their experience is unique, exceptional, and shared by no one else.'
~Lastly, tension with parents is raised because adolescents are much more apt to engage in risky behavior than later in life. In large part, their riskiness is due to the immaturity of brain systems that regulate impulse control, some of which do not fully develop until people are in their 20s.
Adolescent Suicide
Some teenagers experience unusually severe psychological problems. The problems are sometimes so extreme that adolescents take their own lives.
~Suicide is the third leading cause of death amongst adolescents (after accidents and homicide) in the United States. More adolescents and young adults die from suicide than cancer, heart disease, AIDS, birth defects, stroke, pneumonia and influenza, and chronic lung disease combined.
~A teenager commits suicide every 90 minutes. Overall, as many as 200 adolescents may attempt to commit suicide for every one who actually takes his or her own life.
~Male adolescents are five times more likely to commit suicide than females, although females attempt suicide more often than males. The rate of suicide is significantly greater among whites than nonwhites. However, over the past two decades, the suicide rate of African-American males has increased much more rapidly than that of white males. Native Americans have the highest rate of any ethnic group, while Asian Americans have the lowest rate.
~Rates of suicide are higher among adolescents than any other age group, except for the elderly. Some suggest this is due to the sharp rise in stress that teenagers experience - academic and social pressure, alcoholism, drug abuse, and family difficulties. Another factor is depression, characterized by unhappiness, extreme fatigue, and a profound sense of hopelessness. In some cases, adolescents who commit suicide are perfectionists who are inhibited socially or prone to extreme anxiety when they face social or academic challenges.
~Family background and adjustment difficulties are also related to suicide. Longstanding histories of conflicts between parents and children may lead to adolescent behavior problems, such as delinquency, dropping out of school, and aggressive behavior problems.
Section 5 - Adulthood
MAIN IDEA QUESTIONS
What are the principal kinds of physical, social, and intellectual changes that occur in early and middle adulthood, and what are their causes?
How does the reality of late adulthood differ from the stereotypes about that period?
How can we adjust to death?
VOCABULARY
emerging adulthood - the period beginning in the late teenage years and extending into the mid-20s
menopause - the period during which women stop menstruating and are no longer fertile
genetic preprogramming theories of aging - theories that suggest that human cells have a built-in time limit to their reproduction and that they are no longer able to divide after a certain time
wear-and-tear theories of aging - theories that suggest that mechanical functions of the body simply stop working efficiently
Alzheimer's disease - a progressive brain disorder that leads to a gradual and irreversible decline in cognitive abilities
disengagement theory of aging - a theory that suggests that aging produces a gradual withdrawal from the world on physical, psychological, and social levels
activity theory of aging - a theory that suggests that the elderly who are most successful while aging are those who maintain the interests and activities they had during middle age
life review - the process by which people examine and evaluate their lives
"I thought I got better as I got older. I found out that wasn't the case in a real hurry last year. After going twelve years in professional football and twelve years before that in amateur football without ever having surgery performed on me, the last two seasons of my career I went under the knife three times. It happened very quickly and without warning, and I began to ask myself, 'Is this age? Is this what's happening?' Because up until that moment, I'd never realized that I was getting older." - Brian Sipes
Psychologists generally agree that early adulthood begins around age 20 and lasts until about age 40 to 45 when middle adulthood begins and continues until around age 65. These eras of life have been studied less than any other stage. Physical changes are less apparent and more gradual, while social changes of the period defy simple categorization.
~Emerging adulthood is the period beginning in the late teenage years and extending into the mid-20s. People are no longer adolescents, but they haven't fully taken on the responsibilities of adulthood. They are still engaged in determining who they are and what their life and career paths should be. The age at which most people marry, have children, and begin their career has risen significantly.
PHYSICAL DEVELOPMENT: THE PEAK OF HEALTH
For most people, early adulthood marks the peak of physical health. From about 18 to 25 years of age, people's strength is the greatest, their reflexes are quickest, and their chances of dying from disease are quite slim. Moreover, reproductive capabilities are at their highest level.
~Around age 25, the body becomes slightly less efficient and more susceptible to disease. Still, most people stay remarkably healthy during early adulthood.
~During middle adulthood, people gradually become aware of changes in their bodies - weight gain, sense organs become less sensitive, and slower reactions to stimuli. Physical declines are still minor and often unnoticeable.
~On average, during their late 40s or early 50s, women begin menopause, during which they stop menstruating and are no longer fertile. Because this is accompanied by a reduction in estrogen, women sometimes experience symptoms such as hot flashes, sudden sensations of heat. Many can be treated through hormone therapy (HT) win which women take the hormones estrogen and progesterone. This treatment, however, can pose several dangers - increased risk of breast cancer, blood clots, and coronary heart disease.
~For men, aging during middle adulthood is somewhat subtler. Sperm production decreases, and the frequency of orgasm tends to decline. Still, men remain fertile and capable of fathering children until well into late adulthood.
SOCIAL DEVELOPMENT: WORKING AT LIFE
During this period, people typically launch themselves into careers, marriage, and families. The entry to early adulthood is usually marked by leaving one's childhood home and entering the world of work. People envision life goals and make career choices.
~In their early 40s, however, people may begin to question their lives as they enter a period called the midlife transition. The passage into middle age is relatively calm for most people, although the idea that life will end at some point becomes more influential in their thinking, which can lead them to question their past accomplishments. There is little evidence to suggest that the so-called "midlife crisis" actually exists. Most 40-year-olds view their lives and accomplishments positively enough to proceed relatively smoothly through midlife, and the 40s and 50s are often a particularly rewarding period. Rather than looking to the future, people concentrate on the present; involvement with families, friends, social groups takes on new importance.
~During the last stages of adulthood, people become more accepting of others and their own lives and are less concerned about issues or problems that once bothered them. They accept the fact that death is inevitable, and try to understand their accomplishments in terms of the broader meaning of life.
MARRIAGE, CHILDREN, AND DIVORCE: FAMILY TIES
The percentage of U.S. households made up of unmarried couples has increased dramatically over the last two decades. The average age at which marriage takes place is higher than at any other time since the turn of the twentieth century. These trends suggest the institution of marriage has changed considerably from earlier historical periods.
~The probability of divorce is high when people do marry, especially for younger couples. Divorce rates have been declining since peaking in 1981 - however, half of all marriages end in divorce. Two-fifths of children experience the breakup of their parents' marriages before they are 18 years old. This is not just a U.S. phenomenon, as divorce rates have accelerated in most industrialized countries. In South Korea, the divorce rate quadrupled from 1990 to 2002, from 11% to 47%.
~These trends have doubled the number of single-parent households in the U.S. over the last two decades. Almost 25% of all family households are now headed by a single parent, as opposed to 13% in 1970. If this trend persists, three-fourths of children will spend time in a single-parent household before reaching the age of 18. Almost 60% of all black children and more than a third of all Hispanic children live in homes with only one parent (most often the mother).
~What are the economic and emotional consequences for children living in homes with only one parent?
Economically less well off (more than one-third with incomes below the poverty line). Good child care at an affordable price is difficult to find. Emotionally, parents' separations lead to difficulties in establishing close relationships with them later in life. Children may blame themselves for the breakup or feel pressure to take sides. Still, research shows that children from single-parent families are no less well adjusted than those from two-parent families. In fact, children may be more successful growing up in a harmonious single-parent family than a two-parent family that engages in continuous conflict.
CHANGING ROLES OF MEN AND WOMEN
More women than ever before act simultaneously as wives, mothers, and wage earners - in contrast to women in traditional marriages in which the husband is the sole wage earner and the wife assumes primary responsibility for care of the home and children. Close to 75% of all married women with school-age children are now employed outside the home, and 55% of mothers with children under age 6 are working. In the mid-1960s, only 17% of mothers of 1-year-olds worked full-time; now, more than half are in the labor force.
~Even in marriages in which the spouses hold jobs that have similar status and require similar hours, the distribution of household tasks between husbands and wives has not changed substantially. Working wives are still more likely than husbands to feel responsible for traditional homemaking tasks such as cooking and cleaning. In contrast, husbands still view themselves as responsible for tasks such as repairing broken appliances and doing yardwork.
Women's "Second Shift"
Working mothers can put in a staggering number of hours. One survey combined the number of hours on the job and at home for employed mothers of children under 3 to find they put in an average of 90 hours per week.
~Instead of careers being a substitute for what women do at home, they are often an addition to the role of homemaker. Some wives feel resentment toward husbands who spend less time on child care and housework than wives had expected before the birth of their children.
LATER YEARS OF LIFE: GROWING OLD
By focusing on the period of life that begins around age 65, gerontologists are clarifying the capabilities of older adults. There are significant developmental processes which continue even during old age. As life expectancy increases, the number of people who reach older adulthood will continue to grow substantially. Developing an understanding of late adulthood has become a critical priority for psychologists.
PHYSICAL CHANGES IN LATE ADULTHOOD: THE AGING BODY
Napping, eating, walking, conversing. These relatively nonstrenuous activities represent the typical pastimes of late adulthood. It is striking, however, that these activities are the most common leisure activities reported by college students. While they cite more active pursuits - such as sailing or playing basketball - they spent most of their free time napping, eating, walking, and conversing.
~Many physical changes are, of course, brought on by aging; thinning and graying of hair, folding and wrinkling of skin, and slight loss of height as the thickness of the disks between vertebrae in the spine decrease. Sensory capabilities decrease: vision, hearing, smell, and taste become less sensitive. Reaction time slows and physical stamina changes.
~Genetic preprogramming theories of aging suggest that human cells have a built-in time limit to their reproduction. After a certain time, cells stop dividing or become harmful to the body - as if an automatic self-destruct button had been pushed.
~Wear-and-tear theories of aging, in contrast, suggest that the mechanical functions of the body simply work less efficiently as people age. Waste by-products of energy production eventually accumulate, and mistakes are made when cells divide. The body, in effect, wears out like an old automobile.
~Evidence supports both theories, and both may contribute to natural aging. Physical aging is not a disease, it is a natural biological process. Many physical functions do not decline with age - sex remains pleasurable until well into old age (although the frequency of sexual activity decreases), and some people report sexual pleasure increasing with old age.
COGNITIVE CHANGES: THINKING ABOUT - AND DURING - LATE ADULTHOOD
Most research indicates that a common stereotype about older adults - that they are forgetful and confused - is far from an accurate assessment of old people's capabilities.
~Poorer performances on IQ tests may be due to gradual decreases in reaction time - the physical part of the test - which has nothing to do with intellectual capabilities. Older people are often less healthy than younger ones; when only healthy older adults are compared to healthy younger adults, intellectual differences are far less evident. The average number of years in school is often lower for older adults, who may be less motivated to perform well on traditional intelligence tests than younger people. Older adults sometimes perform better on tests of practical intelligence. Fluid intelligence tends to decline in late adulthood, while crystallized intelligence seems to remain steady.
Memory Changes In Late Adulthood: Are Older Adults Forgetful?
Most evidence suggests memory loss is not inevitable. Cultures in which older adults are held in high esteem, such as mainland China, are less likely to show memory losses than those living in cultures where the expectation exists that memory will decline.
~Losses of memory tend to be limited to episodic memories that relate to specific experiences in people's lives. Semantic memories (general knowledge) and implicit memory (memories of which we are not consciously aware) are largely unaffected by age. Declines in episodic memory can be traced to life changes, such as retiring from the work force, thus reducing the kind of consistent intellectual challenges faced on the job along the amount of practice using such memory. Sometimes they may be less motivated to remember things once retired.
~Senility is a broad, imprecise term typically applied to older adults who experience progressive deterioration of mental abilities, including memory loss, disorientation to time and place, and general confusion. Most gerontologists view this term as having outlived its usefulness. Such symptoms are deemed to be caused by some other factor.
~One known disease is Alzheimer's disease which is a progressive brain disorder that leads to a gradual and irreversible decline in cognitive abilities. More than 5 million Americans have the disease, and one in eight people age 65 and older are afflicted. Unless a cure is found, some 14 million people will experience Alzheimer's by 2050. Alzheimer's occurs when production of the beta amyloid precursor protein goes awry, producing large clumps of cells that trigger inflammation and deterioration of nerve cells. The brain shrinks, neurons die, and several areas of the hippocampus and frontal and temporal lobes deteriorate. So far, there is no effective treatment.
The Social World Of Late Adulthood: Old But Not Alone
Another misconception is that late adulthood inevitably brings loneliness. Only a small number of older adults report that loneliness is a serious problem. Certainly retirement and/or the death of a spouse may bring about a major shift in the role older adults play. These events can also bring about changes in economic well-being.
~According to the disengagement theory of aging, aging produces a gradual withdrawal from the world on physical, psychological, and social levels. Such disengagement is beneficial at a time of life when social relationships will inevitably be ended by death.
~According to the activity theory of aging, people who age most successfully are those who maintain the interests, activities, and level of social interaction they experienced during middle childhood. The theory argues that late adulthood should reflect a continuation, as much as possible, of the activities in which people participated during the earlier part of their lives.
~Little research supports disengagement theory, while most research support activity theory. However, not all people in late adulthood need a life filled with activities and social interaction to be happy; as in every stage of life, some older adults are just as satisfied leading a relatively inactive, solitary existence. Positive self-perceptions of aging are associated with increased longevity.
~Most people engage in a process of life review in which they examine and evaluate their lives. People in late adulthood come to a better understanding of themselves, sometimes resolving lingering problems and facing their lives with greater wisdom and serenity.
Moral Development In Women
One glaring shortcoming in Kohlberg's research is that he primarily used male participants. Psychologist Carol Gilligan argues that because of men and women's distinctive socialization experiences, a fundamental difference exists in the way each gender views moral behavior. Men view morality primarily in terms of broad principles, such as justice and fairness. In contrast, women see it in terms of responsibility toward individuals and willingness to make sacrifices to help a specific individual within a context of a particular relationship. Compassion for individuals is a more salient factor in moral behavior than it is for men.
~Gilligan suggests that women's morality centers on individual well-being and social relationships - a morality of caring. Compassionate concern for the welfare of others represents the highest level or morality.
SOCIAL DEVELOPMENT: FINDING ONE'S SELF IN A SOCIAL WORLD
Erikson's Theory Of Psychosocial Development: The Search For Identity
Erikson's stages of psychosocial development. According to Erikson, people proceed through eight stages of psychosocial development across their lives. He suggested that each stage requires the resolution of a crisis or conflict and may produce both positive and negative outcomes.
~Before we rush to congratulate authoritative parents and condemn authoritarian, permissive, and uninvolved ones, it is important to note that in many cases non-authoritative parents also produce perfectly well-adjusted children. Children are born with a particular temperament. Some children are naturally easygoing and cheerful, whereas others are irritable and fussy, or quiet. Children also vary considerably in their degree of resilience, the ability to overcome circumstances that place them at high risk for psychological or even physical harm. In a sense, resilient children try to shape their own environment rather than being victimized by it.
~These approaches apply primarily to U.S. society, which values children's independence and diminishing reliance on their parents. In contrast, Japanese parents encourage dependence to promote the values of cooperation and community. EX: Japanese mothers believe it is a punishment to make a young child sleep alone.
~In sum, a child's upbringing results from the child-rearing philosophy parents hold, the specific practices they use, and the nature of their own and their child's personalities. Behavior is a function of a complex interaction of environmental and genetic factors.
Erikson's Theory of Psychosocial Development. Psychoanalyst Erik Erikson viewed the developmental stages that occur throughout life as a series of eight stages of psychosocial development; of these, four occur during childhood. Psychosocial development involves changes in our interaction and understanding of one another as well as in our knowledge and understanding of ourselves as members of society.
~Erikson suggests that passage through each of these stages necessitates the resolution of a crisis or conflict. He represents each stage as a pairing of the most positive and the most negative aspects of the crisis of that period.
Trust-versus-mistrust stage (birth to 1 1/2 years) - infants develop feelings of trust if their physical requirements and psychological needs for attachment are consistently met and their interactions with the world are generally positive. Inconsistent care and unpleasant interactions with others can lead to mistrust and leave an infant unable to meet the challenges required in the next stage of development.
Autonomy-versus-shame-and-doubt stage (ages 1 1/2 to 3 years) - toddlers develop autonomy and independence in exploration and freedom are encouraged, or they experience shame, self-doubt, or unhappiness if they are overly restricted and protected.
Initiative-versus-guilt stage (ages 3 to 6) - children's desire to act independently conflicts with the guilt that comes from the unintended and unexpected consequences of such behavior.
Industry-versus-inferiority stage (ages 6 to 12) - increasing competency in all areas characterizes successful psychosocial development. These areas include social interactions, academic skills, and more.
Cognitive Development: Children's Thinking About The World
Piaget's Theory of Cognitive Development.
Sensorimotor stage: Birth to 2 years. Children base their understanding of the world primarily on touching, sucking, chewing, shaking, and manipulating objects. They lack object permanence - the awareness that objects, and people, continue to exist even when they are out of sight.
Preoperational stage: 2 to 7 years. Children develop the use of language, while using symbols (EX: pushing a book across the floor pretending it is a car). They use egocentric thought - the child views the world entirely from his or her own perspective. Children do not yet understand the principle of conservation - the knowledge that quantity is unrelated to the physical appearance of objects (EX: A tall thin glass holds the same amount of liquid as a small, broad glass.)
Concrete Operational: 7 to 12 years. Mastery of the principle of conservation begins in this stage. Children develop the ability to think in a more logical manner and begin to overcome some of the egocentrism characteristic. They still have difficulty answering larger questions of abstract nature.
Formal Operational: 12 years to Adulthood. This stage produces thinking that is abstract, normal, and logical.
Information-Processing Approaches: Charting Children's Mental Programs
Vygotsky's View of Cognitive Development: Considering Culture.
Vygotsky suggests the culture we are raised in significantly affects our development. Learning occurs as the result of social interaction in which children work together jointly to solve problems. Children's cognitive development occurs when they encounter information in the zone of proximal development (ZPD) - the level at which a child can almost, but not fully, perform or comprehend a task on his or her own. If a problem falls within a child's ZPD, they can increase their understanding or master the new task... in contrast, if the information lies outside the child's ZPD, they will not be able to master it.
Section 4 - Adolescence: Becoming an Adult
MAIN IDEA QUESTION
What major physical, social, and cognitive transitions characterize adolescence?
VOCABULARY
adolescence - the developmental stage between childhood and adulthood
puberty - the period at which maturation of the sexual organs occurs, beginning at about age 11 or 12 for girls and 13 or 14 for boys
identity-versus-role-confusion stage - according to Erikson, a time in adolescence of major testing to determine one's unique qualities
identity - the distinguishing character of the individual; who each of us is, what our roles are, and what we are capable of
intimacy-versus-isolation stage - according to Erikson, a period during early adulthood that focuses on developing close relationships
generativity-versus-stagnation stage - according to Erikson, a period in middle adulthood during which we take stock of our contributions to family and society
ego-integrity-versus-despair stage - according to Erikson, a period from late adulthood until death during which we review life's accomplishments and failures
PHYSICAL DEVELOPMENT: THE CHANGING ADOLESCENT
If you think back to the start of your own adolescence, the most dramatic changes you probably remember are physical. The physical changes that occur at the start of adolescence result largely from the secretion of various hormones, and they affect virtually every aspect of an adolescent's life. Weight and height increase rapidly because of a growth spurt that typically occurs around age 10 for girls and age 12 for boys. Adolescents may grow as much as 5 inches in one year.
~Puberty, the period at which maturation of the sex organs occurs, begins at about age 11 or 12 for girls, when menstruation starts. There are, however, wide variations which begin as early as age 8 or 9 and as late as age 16. In Western cultures, average age of sexual maturity has been steadily decreasing over the last century, likely as a result of improved nutrition and medical care. Sexual attraction to others begins even before the maturation of the sexual organs at around age 10.
~For boys, the onset of puberty is marked by their first ejaculation, known as spermarche. This usually occurs around age 13. At first, relatively few sperm are produced, but the amount increases significantly within a few years.
~The age at which puberty begins has implications for the way adolescents feel about themselves - as well as the way other treat them. Early-maturing boys do better in athletics, are generally more popular with peers, and have more positive self-concepts.
~The picture differs for girls. Although early-maturing girls are more sought after as dates and have better self-esteem than later-maturing girls, some consequences of early physical maturation may be less positive. EX: Early breast development may set them apart from their peers and be a source of ridicule.
~Late physical maturation may produce certain psychological difficulties for both boys and girls. Boys who are smaller and less coordinated than their more mature peers tend to feel ridiculed and less attractive. Similarly, late-maturing girls are at a disadvantage in middle school and early high school. They hold relatively low social status and may be overlooked in dating.
MORAL AND COGNITIVE DEVELOPMENT: DISTINGUISHING RIGHT FROM WRONG
Kohlberg's Theory Of Moral Development
Developmental psychologist Lawrence Kohlberg theorized that people move through a three-level sequence of moral reasoning in a fixed order. However, he contended that few people ever reach the highest level of moral reasoning.
Sample Moral Reasoning of Subjects