Ch 9 - Physical and Cognitive Development in Adolescence

Peers influence on substance abuse in adolescense

Along with parents, peers play a very important role in adolescent substance use. - When adolescents' peers and friends use drugs, the adolescents are more likely to also use drugs. - A large-scale national study of adolescents indicated that friends' use of alcohol was a stronger influence on alcohol use than parental use

Education's influence on substance abuse in adolescense

Educational success is also a strong buffer against the emergence of drug problems in adolescence. - In one study, early educational achievement considerably reduced the likelihood that adolescents would develop drug problems, including alcohol abuse, smoking, and abuse of various illicit drugs

Ethnic Variations in adolescent pregnancy

Ethnic variations characterize birth rates for U.S. adolescents. - Latina adolescents are more likely than African American and non-Latina White adolescents to have a child. - Latina and African American adolescent girls who have a child are also more likely to have a second child than are non-Latina White adolescent girls

The Formal Operational Stage

Formal operational thought is more abstract than concrete operational thought. - Adolescents are no longer limited to actual, concrete experiences as anchors for thought. - They can conjure up make-believe situations, abstract propositions, and events that are purely hypothetical, and can try to reason logically about them. - The abstract quality of thinking during the formal operational stage is evident in the adolescent's verbal problem-solving ability. - The concrete operational thinker needs to see the concrete elements A, B, and C to be able to make the logical inference that if A = B and B = C, then A = C, whereas the formal operational thinker can solve this problem merely through verbal presentation. - Another indication of the abstract quality of adolescents' thought is their increased tendency to think about thought itself. - One adolescent commented, "I began thinking about why I was thinking what I was. - Then I began thinking about why I was thinking about what I was think-ing about what I was." - If this sounds abstract, it is, and it characterizes the adolescent's enhanced focus on thought and its abstract qualities. - Accompanying the abstract nature of formal operational thought is thought full of idealism and possibilities, especially at the beginning of the formal operational stage. - Adolescents engage in extended speculation about ideal characteristics—qualities they desire in themselves and in others. - Such thoughts often lead adolescents to compare themselves with others in regard to such ideal standards. - And their thoughts are often fantasy flights into future possibilities.

What trends in adolescent sexual activity have occurred in recent decades?

From 1991 to 2015, fewer adolescents reported any of the following: ever having had sexual intercourse, currently being sexually active, having had sexual intercourse before the age of 13, and having had sexual intercourse with four or more persons during their lifetime

Repeated Adolescent Pregnancy

Indeed, a special concern is repeated adolescent pregnancy. - In a recent national study, the percentage of teen births that were repeat births decreased from 2004 (21 percent) to 2015 (17 percent). - In a recent meta-analysis, use of effective contraception, especially LARC, and education-related factors (higher level of education and school continuation) resulted in a lower incidence of repeated teen pregnancy, while depression and a history of abortion were linked to a higher percentage of repeated teen pregnancy

Struggles of Gay and Lesbian Individuals

It is commonly believed that most gay and lesbian individuals quietly struggle with same-sex attractions in childhood, do not engage in heterosexual dating, and gradually recognize that they are gay or lesbian in middle to late adolescence. - Many youths do follow this developmental pathway, but others do not. - For example, many people have no recollection of early same-sex attractions and experience a more abrupt sense of their same-sex attraction in late adolescence. - Researchers also have found that the majority of adolescents with same-sex attractions also experience some degree of other-sex attractions. - Even though some adolescents who are attracted to individuals of their own sex fall in love with these individuals, others claim that their same-sex attractions are purely physical. - In sum, gay and lesbian youth have diverse patterns of initial attraction, often have bisexual attractions, and may have physical or emotional attraction to same-sex individuals but do not always fall in love with them. - Further, the majority of sexual minority (gay, lesbian, and bisexual) adolescents have competent and successful paths of development through adolescence and become healthy and productive adults. - However, in a recent large-scale study, sexual minority adolescents were more likely to engage in health-risk behaviors (greater drug use and sexual risk taking, for example) than heterosexual adolescents

High School

Just as there are concerns about U.S. middle school education, so are there concerns about U.S. high school education. - A recent analysis indicated that only 25 percent of U.S. high school graduates have the academic skills to succeed in college. - Not only are many high school graduates poorly prepared for college, they also are poorly prepared for the demands of the modern, high-performance workplace. - Critics stress that many high schools have low expectations for success and inadequate standards for learning. - Critics also argue that too often high schools foster passivity instead of creating a variety of pathways for students to achieve an identity. - Many students graduate from high school with inadequate reading, writing, and mathematical skills—including many who go on to college and must enroll in remediation classes to complete their coursework. - Other students drop out of high school and do not have skills that will allow them to obtain decent jobs, much less to be informed citizens.

Might chang-ing sleep patterns in adolescence contribute to adolescents' health-compromising behaviors?

Recently there has been a surge of interest in adolescent sleep patterns - A longitudinal study in which adolescents completed daily diaries during 14-day periods in ninth, tenth, and twelfth grades found that regardless of how much students studied each day, when the students sacrificed sleep time to study more than usual, they had difficulty understanding what was taught in class and were more likely to struggle with class assignments the next day. - Researchers also have found that adolescents who get less than 7.7 hours of sleep per night on average have more emotional and peer-related problems, higher anxiety, and a higher level of suicidal ideation. - And a recent national study of more than 10,000 13- to 18-year-olds revealed that later weeknight bedtime, shorter week-night sleep duration, greater weekend bedtime delay, and both short and long periods of weekend oversleep were linked to increased rates of anxiety, mood, substance abuse, and behavioral disorders

What is the most common type of sex among adolescents?

Research indicates that oral sex is now a common occurrence among U.S. adolescents. - In a recent national survey of more than 7,000 15- to 24-year-olds, 58.6 percent of the females reported ever having performed oral sex and 60.4 percent said that they had ever received oral sex. - Also, in a previous survey, 51 percent of U.S. 15- to 19-year-old boys and 47 percent of girls in the same age range said they had engaged in oral sex. - One study also found that among female adolescents who reported having vaginal sex first, 31 percent reported having a teen pregnancy, whereas among those who initiated oral-genital sex first, only 8 percent reported having a teen pregnancy. - Thus, how adolescents initiate their sex lives may have positive or negative consequences for their sexual health

Do sleep patterns change in emerging adulthood?

Research indicates that they do. - One study revealed that more than 60 percent of college students were categorized as poor-quality sleepers. - In this study, the weekday bedtimes and rise times of first-year college students were approximately 1 hour and 15 minutes later than those of seniors in high school. - However, the first-year college students had later bedtimes and rise times than third- and fourth-year college students, indicating that at about 20 to 22 years of age, a reverse shift in the timing of bedtimes and rise times occurs. - In another study, consistently low sleep duration in college students was associated with less effective attention the next day. - Also, in a recent study of college students, a higher level of text messaging (greater number of daily texts, awareness of nighttime cell phone notifications, and compulsion to check nighttime notifications) was linked to a lower level of sleep quality

exercise in adolescence

Researchers have found that individuals become less active as they reach and progress through adolescence. - A national study revealed that only 48.6 percent of U.S. adolescents met the federal government's exercise recommendations (a minimum of 60 minutes of moderate to vigorous exercise per day). - This national study also found that adolescent girls were much less likely to engage in 60 minutes or more of vigorous exercise per day in five of the last seven days (42 percent) than were boys (61 percent). - Ethnic differences in exercise participation rates of U.S. adolescents also occur, and these rates vary by gender. - In the national study just mentioned, non-Latino White boys exercised the most, African American and Latino girls the least

Of the striking changes that were taking place in your body, what was the first to occur? (Puberty in Males)

Researchers have found that male pubertal characteristics typically develop in this order: increase in penis and testicle size, appear-ance of straight pubic hair, minor voice change, first ejaculation (which usually occurs through masturbation or a wet dream), appearance of kinky pubic hair, onset of maximum growth in height and weight, growth of hair in armpits, more detectable voice changes, and, finally, growth of facial hair

Family factors associated with sexual risk taking

A number of family factors are associated with sexual risk taking. - For example, one study found that difficulties and disagreements between Latino adolescents and their parents were linked to the adolescents' early sexual initiation. - Also, a recent study revealed that adolescents who reported greater parental knowledge of their whereabouts and more family rules about dating in the eighth grade were less likely to initiate sex from the eighth to tenth grade. - And a recent study revealed that of a number of parenting practices, the factor that best predicted a lower level of risky sexual behavior by adolescents was supportive parenting

Substance abuse in early childhood and early adolescense

A special concern involves adolescents who begin to use drugs early in adolescence or even in childhood. - A longitudinal study of individuals from 8 to 42 years of age found that early onset of drinking was linked to increased risk of heavy drinking in middle age. - Another study revealed that the onset of alcohol use before age 11 was linked to a higher risk for alcohol dependence in early adulthood. - Further, a longitudinal study found that earlier age at first use of alcohol was linked to risk of heavy alcohol use in early adulthood. - And another study indicated that early- and rapid-onset trajectories of alcohol, marijuana, and substance use were associated with substance abuse in early adult-hood

Effective programs to discourage drop outs in students

According to a research review, the most effective programs to discourage dropping out of high school provide early reading support, tutoring, counseling, and mentoring. - Clearly, then, early detection of children's school-related difficulties and getting children engaged with school in positive ways are important strategies for reducing the dropout rate

Adolescent Health

Adolescence is a critical juncture in the adoption of behaviors that are relevant to health. - Many of the behaviors that are linked to poor health habits and early death in adults begin during adolescence. - Conversely, the early formation of healthy behavior patterns, such as regular exercise and a preference for foods low in fat and cholesterol, not only has immediate health benefits but helps in adulthood to delay or prevent disability and mortality from heart disease, stroke, diabetes, and cancer

Service Learning

Service learning is a form of education that promotes social responsibility and service to the community. - Adolescents engage in activities such as tutoring, helping older adults, working in a hospital, assisting at a child-care center, or cleaning up a vacant lot to make it into a play area. - An important goal of service learning is to encourage adolescents to become less self-centered and more strongly motivated to help others. - Service learning is often more effective when two conditions are met: (1) giving students some degree of choice in the service activities in which they participate, and (2) providing students with opportunities to reflect about their participation. - A key feature of service learning is that it benefits not only adolescents but also the recipients of their help. - One eleventh-grade student worked as a reading tutor for students from low-income back-grounds with reading skills well below their grade levels. - Until she did the tutoring, she had not realized how many students had not experienced the same opportunities that she had when she was growing up. - An especially rewarding moment was when one young girl told her, "I want to learn to read like you so I can go to college when I grow up."

Contraceptive use in adolescence

Sexual activity brings considerable risks if appropriate safeguards are not taken. - Youth encounter two kinds of risks: unintended, unwanted pregnancy and sexually transmitted infections. - Both of these risks can be reduced significantly if condoms are used. - Too many sexually active adolescents still do not use contraceptives, use them inconsistently, or use contraceptive methods that are less effective than others. - In 2015, 14 percent of sexually active adolescents did not use any contraceptive method the last time they had sexual intercourse. - Researchers have found that U.S. adolescents are less likely to use condoms than their European counterparts. - Recently, a number of leading medical organizations and experts have recommended that adolescents use long-acting reversible contraception (LARC). - These include the Society for Adolescent Health and Medicine (2017), the American Academy of Pediatrics and American College of Obstetrics and Gynecology (Allen & Barlow, 2017), and the World Health Organization (2018). - LARC consists of the use of intrauterine devices (IUDs) and contraceptive implants, which have much lower rates of unwanted pregnancy than birth control pills and condoms

Ethnic Group and sexual initiation

Sexual initiation varies by ethnic group in the United States - African Americans are likely to engage in sexual behaviors earlier than other ethnic groups, whereas Asian Americans are likely to engage in them later. - In a more recent national U.S. survey of ninth- to twelfth-graders, 48.5 percent of African Americans, 42.5 percent of Latinos, and 39.9 percent of non-Latino Whites said they had experienced sexual intercourse. - In this study, 8 percent of African Americans (compared with 5 percent of Latinos and 2.5 percent of non-Latino Whites) said they had their first sexual experience before 13 years of age.

What causes students to drop out?

Students drop out of school for many reasons. - In one study, almost 50 percent of the dropouts cited school-related reasons for leaving school, such as not liking school or being expelled or suspended. - Twenty percent of the dropouts (but 40 percent of the Latino students) cited economic reasons for leaving school. - One-third of the female students dropped out for personal reasons such as pregnancy or marriage.

Changes in the corpus callosum

The corpus callosum, where nerve fibers connect the brain's left and right hemispheres, thickens in adolescence, and this improves adolescents' ability to process information. - Earlier we described advances in the development of the prefrontal cortex—the highest level of the frontal lobes involved in reasoning, decision making, and self- control. However, the prefrontal cortex doesn't finish maturing until the emerging adult years—approximately 18 to 25 years of age—or later

The Transition to Middle or Junior High School

The transition to middle or junior high school takes place at a time when many changes—in the individual, the family, school—are occurring simultaneously. - These changes include puberty and concerns about body image; the emergence of at least some aspects of formal operational thought, including changes in social cognition; increased responsibility and decreased dependency on parents; change to a larger, more impersonal school structure; change from one teacher to many teachers and from a small, homogeneous set of peers to a larger, more heterogeneous set; and an increased focus on achievement and performance. - Moreover, when students make the transition to middle or junior high school, they experience the top-dog phenomenon, moving from being the oldest, biggest, and most powerful students in the elementary school to being the youngest, smallest, and least powerful students.

Outcomes of Adolescent pregnancy

Adolescent pregnancy creates health risks for both the baby and the mother. - Infants born to adolescent mothers are more likely to have low birth weights—a prominent factor in infant mortality—as well as neurological problems and childhood illness. - Adolescent mothers are more likely to be depressed and to drop out of school than their peers. - Although many adolescent mothers resume their education later in life, they generally never catch up economically with women who postpone childbearing until their twenties. - Also, a study of African American urban youth found that at 32 years of age, women who had been teenage mothers were more likely to be unemployed, live in poverty, depend on welfare, and not have completed college than were women who had not been teenage mothers. - In this study, at 32 years of age, men who had been teenage fathers were more likely to be unemployed than were men who had not been teenage fathers. - Though the consequences of America's high adolescent pregnancy rate are cause for great concern, it often is not pregnancy alone that leads to negative consequences for an adolescent mother and her offspring. - Adolescent mothers are more likely to come from low-SES backgrounds. - Many adolescent mothers also were not good students before they became pregnant. - However, not every adolescent female who bears a child lives a life of poverty and low achievement. - Thus, although adolescent pregnancy is a high-risk circumstance and adolescents who do not become pregnant generally fare better than those who do, some adolescent mothers do well in school and have positive outcomes. - Serious, extensive efforts are needed to help pregnant adolescents and young mothers enhance their educational and occupational opportunities. - Adolescent mothers also need help in obtaining competent child care and in planning for the future.

Sexually transmitted infections (STIs)

are contracted primarily through sexual contact, including oral-genital and anal-genital contact. - Every year more than 3 million American adolescents (about one-fourth of those who are sexually experienced) acquire an STI (Centers for Disease Control and Prevention, 2018). - In a single act of unprotected sex with an infected partner, a teenage girl has a 1 percent risk of getting HIV, a 30 percent risk of acquiring genital herpes, and a 50 percent chance of contracting gonorrhea. - Other very widespread STIs are chlamydia and human papillomavirus (HPV).

Peter Benson and his colleagues

argue that the United States has a fragmented social policy for youth that too often has focused only on the negative developmental deficits of adolescents, especially health-compromising behaviors such as drug use and delinquency, and not enough on positive, strength-based approaches. - According to Benson and his colleagues, a strength-based approach to social policy for youth adopts more of a wellness perspective, places particular emphasis on the existence of healthy conditions, and expands the concept of health to include the skills and competencies needed to succeed in employment, education, and life. It moves beyond the eradication of risk and deliberately argues for the promotion of well-being.

Puberty

is a brain-neuroendocrine process occurring primarily in early adolescence that provides stimulation for the rapid physical changes that take place during this period of development. - Puberty is not a single, sudden event. We know whether a young boy or girl is going through puberty, but pinpointing puberty's beginning and end is difficult. - Among the most noticeable changes are signs of sexual maturation and increases in height and weight.

adolescent egocentrism

is the heightened self-consciousness of adolescents. - David Elkind (1976) maintains that adolescent egocentrism has two key components—the imaginary audience and personal fable.

hormones

powerful chemical substances secreted by the endocrine glands and carried through the body by the bloodstream

Growth spurt differences between males and females

the growth spurt occurs approximately two years earlier for girls than for boys. - The mean age at the beginning of the growth spurt in girls is 9; for boys, it is 11. - The peak rate of pubertal change occurs at 11½ years for girls and 13½ years for boys. - During their growth spurt, girls increase in height about 3½ inches per year, boys about 4 inches. - Boys and girls who are shorter or taller than their peers before adolescence are likely to remain so during adolescence.

Examples of situations where adolescents need to engage in cognitive control:

• making a real effort to stick with a task, avoiding interfering thoughts or environ-mental events, and instead doing what is most effective; • stopping and thinking before acting to avoid blurting out something that a minute or two later they will wish they hadn't said; • continuing to work on something that is important but boring when there is some-thing a lot more fun to do, inhibiting their behavior and doing the boring but important task, saying to themselves, "I have to show the self-discipline to finish this."

Decision Making

- Adolescence is a time of increased decision making—which friends to choose; which person to date; whether to have sex, buy a car, go to college, and so on. How competent are adolescents at making decisions? - Older adolescents are described as more competent than younger adolescents, who in turn are more competent than children. - Compared with children, young adolescents are more likely to generate different options, examine a situation from a variety of perspectives, anticipate the consequences of decisions, and consider the credibility of sources. - In risky situations it is important for an adolescent to quickly get the gist, or meaning, of what is happening and glean that the situation is a dangerous context, which can cue personal values that will protect the adolescent from making a risky decision

Controlling Attention in Adolescence (Cognitive Control)

- Controlling attention is a key aspect of learning and thinking in adolescence and emerging adulthood - Distractions that can interfere with attention come from the external environment (such as other students talking while the student is trying to listen to a lecture, or the student turning on a laptop or phone during a lecture to look at Facebook, for example) or intrusive distractions from competing thoughts in the individual's mind. - Self-oriented thoughts, such as worrying, self-doubt, and intense emotionally laden thoughts may interfere with focusing attention on thinking task

What is a major controversy in sex education?

- Currently, a major controversy in sex education is whether schools should have an abstinence-only program or a program that emphasizes contraceptive knowledge. - Recent research reviews have concluded that abstinence-only programs do not delay the initiation of sexual intercourse and do not reduce HIV risk behaviors. - Recently there has been an increased emphasis on abstinence-only-until-marriage (AOUM) policies and programs in many U.S. schools. - However, a major problem with such policies and programs is that a very large majority of individuals engage in sexual intercourse at some point in adolescence or emerging adulthood, while the average age when people marry for the first time continues to go up (currently 27 for females, 29 for males in the United States). - The Society for Adolescent Health and Medicine (2017) recently released a policy position that states research evidence indicates that many comprehensive sex education programs successfully delay initiation of sexual intercourse and reduce rates of sexually transmitted infections. - The Society's position also states that research indicates AOUM programs are ineffective in delaying sexual intercourse and reducing other sexual risk behaviors. - Some sex-education programs are starting to include abstinence-plus sexuality by promoting abstinence as well as providing instructions for contraceptive use. - However, despite the evidence that favors comprehensive sex education, there recently has been an increase in government funding for abstinence-only pro-grams. - Also, in some states (Texas and Mississippi, for example), many students still either get abstinence-only instruction or no sex education at all.

What is the order of appearance of physical changes in females?

- First, either the breasts enlarge or pubic hair appears. - Later, hair appears in the armpits. - As these changes occur, the female grows in height and her hips become wider than her shoulders. - Menarche—a girl's first menstruation—comes rather late in the pubertal cycle. ** Marked weight gains coincide with the onset of puberty. During early adolescence, girls tend to outweigh boys, but by about age 14 boys begin to surpass girls. Similarly, at the beginning of the adolescent period, girls tend to be as tall as or taller than boys of their age, but by the end of the middle school years most boys have caught up, or, in many cases, surpassed girls in height.

Do U.S. adolescents got eight or more hours of sleep on an average school night?

- In a national survey of youth, only 27 percent of U.S. adolescents got eight or more hours of sleep on an average school night, 5 percent less than just 2 years earlier. - In this study, the percentage of adolescents getting this much sleep on an average school night decreased as they got older. The National Sleep Foundation (2006) conducted a U.S. survey of 1,602 caregivers and their 11- to 17-year-olds. - Forty-five percent of the adolescents got inadequate sleep on school nights (less than eight hours). - Older adolescents (ninth- to twelfth-graders) got markedly less sleep on school nights than younger adolescents (sixth- to eighth-graders)—62 percent of the older adolescents got inadequate sleep compared with 21 percent of the younger adolescents. - Adolescents who got inadequate sleep (less than eight hours) on school nights were more likely to feel tired, cranky, and irritable; to fall asleep in school; to be in a depressed mood; and to drink caffeinated beverages than their counterparts who got optimal sleep

The Maturation of Focal Activation

- In middle and late childhood, while there is increased focal activation within a specific brain region such as the prefrontal cortex, there also are only limited connections across distant brain regions. - By the time individuals reach emerging adulthood, there are increased connections across brain areas. - The increased connectedness (referred to as brain networks) is especially prevalent across more distant brain regions. - Thus, as children and adolescents mature, greater efficiency and focal activation occurs in local areas of the brain, and simultaneously there is an increase in brain networks across different brain regions - In a recent study, reduced connectivity between the brain's frontal lobes and amygdala during adolescence was linked to increased depression

Substance Use and Abuse in Adolecense

- In the University of Michigan study, the use of drugs among U.S. secondary school students declined in the 1980s but began to increase in the early 1990s, only to later decline in the early part of the first decade of the twenty-first century. - However, from 2006 through 2017, overall use of illicit drugs began increasing again, due mainly to an increase in marijuana use by adolescents. In 2006, 36.5 percent of twelfth-graders reported annual use of an illicit drug, but in 2017 that figure had increased to 39.9 percent. - However, if marijuana use is subtracted from the annual use figures, there has been a significant decline in drug use by adolescents. - When marijuana use is deleted, in 2006, 19.2 percent of twelfth graders used an illicit drug annually, but that figure showed a significant decline to 13.3 percent in 2017 (Johnston & others, 2018). - Marijuana is the most widely used illicit drug by adolescents. - The United States continues to have one of the highest rates of adolescent drug use of any industrialized nation. - Because of the increased legalization of marijuana use for adults in a number of states, youth are likely to have easier access to the drug and usage rates among adolescents are expected to increase in the future. - In the twenty-first century, alcohol and cigarette use have decreased in U.S. adolescents - However, a substantial number of U.S. adolescents are vaping. - In the 2017 national study just described, 19 percent of twelfth-graders, 16 percent of tenth-graders, and 8 percent of eighth-graders vaped nicotine.

Mary Carskadon

- Mary Carskadon has conducted a number of research studies on adolescent sleep patterns. - She has found that when given the opportunity, adolescents will sleep an average of 9 hours and 25 minutes a night. - Most get considerably less than 9 hours of sleep, however, especially during the week. - This shortfall creates a sleep deficit, which adolescents often attempt to make up on the weekend. - She also found that older adolescents tend to be sleepier during the day than younger adolescents are. - Carskadon theorized that this sleepiness was not due to academic work or social pressures. - Rather, her research suggests that adolescents' biological clocks undergo a shift as they get older, delaying their period of wakefulness by about one hour. - A delay in the nightly release of the sleep-inducing hormone melatonin, which is produced in the brain's pineal gland, seems to underlie this shift. - Melatonin is secreted at about 9:30 p.m. in younger adolescents and approximately an hour later in older adolescents. - Carskadon concludes that early school starting times may cause grogginess, inattention in class, and poor performance on tests. - Based on her research, school officials in Edina, Minnesota, decided to start classes at 8:30 a.m. rather than the usual 7:25 a.m. - Since the later start time went into effect, there have been fewer referrals for discipline problems, and the num-ber of students who report being ill or depressed has decreased. - The school system reports that test scores have improved for high school students but not for middle school students. - This finding supports Carskadon's suspicion that early start times are likely to be more stressful for older than for younger adolescents.

The benefits of service learning on adolescent development

- Researchers have found that service learning also benefits adolescent development in other ways, including higher grades in school, increased goal setting, higher self-esteem, an improved sense of being able to make a difference for others, and an increased likelihood that the adolescents will serve as volunteers in the future. - One study found that adolescent girls participated in service learning more than did adolescent boys

What concentrations of certain hormones increase dramatically during adolescence?

- Testosterone is a hormone associated in boys with the development of genitals, an increase in height, and a change in voice. - Estradiol is a type of estrogen; in girls it is associated with breast, uterine, and skeletal development. - In one study, testosterone levels increased eighteen-fold in boys but only two-fold in girls during puberty; estradiol increased eight-fold in girls but only two-fold in boys. - Thus, both testosterone and estradiol are present in the hormonal makeup of both boys and girls, but testosterone dominates in male pubertal development, estradiol in female pubertal development. - The same influx of hormones that grows hair on a male's chest and increases the fatty tissue in a female's breasts may also contribute to psychological development in adolescence.

changes in brain during adolescence

- The dogma of the unchanging brain has been discarded, and researchers are mainly focused on context-induced plasticity of the brain over time - The development of the brain mainly changes in a bottom-up, top-down sequence, with sensory, appetitive (eating, drinking), sexual, sensation-seeking, and risk-taking brain linkages maturing first and higher-level brain linkages such as self-control, planning, and reasoning maturing later. - Recall that researchers have discovered that nearly twice as many synaptic connections are made as we will ever use. - The connections that we do use are strengthened and survive, while the unused ones are replaced by other pathways or disappear. - That is, in the language of neuroscience, these connections will be "pruned." - As a result of this pruning, by the end of adolescence individuals have "fewer, more selective, more effective neuronal connections than they did as children". - And this pruning indicates that the activities adolescents choose to engage in and not to engage in influence which neural connections will be strengthened and which will disappear

How can adolescent decision making improve?

Adolescents need more opportunities to practice and discuss realistic decision making. - Many real-world decisions on matters such as sex, drugs, and daredevil driving occur in an atmosphere of stress that includes time constraints and emotional involvement. - One strategy for improving adolescent decision making is to provide more opportunities for them to engage in role playing and peer-group problem solving.

Do adolescents show a sense of invincibility or invulnerability?

Adolescents also often show a sense of invincibility or invulnerability. - For example, during a conversation with another girl, 14-year-old Margaret says, "Are you kidding? I won't get pregnant." - This sense of invincibility may lead adolescents to believe that they are invulnerable to dangers and catastrophes (such as deadly car wrecks) that hap-pen to other people. - As a result, some adolescents engage in risky behaviors such as drag racing, drug use, and having sexual intercourse without using contraceptives or barriers against STIs. - However, some research studies suggest that rather than perceiving themselves to be invulnerable, adolescents tend to portray themselves as vulnerable to experiencing a premature death

adolescent pregnancy

Adolescent pregnancy is a problematic outcome of sexuality in adolescence that requires major efforts to reduce its occurrence. - In cross-cultural comparisons, the United States continues to have some of the highest rates of adolescent pregnancy and childbearing in the industrialized world, despite a considerable decline in the 1990s. - The U.S. adolescent pregnancy rate is eight times as high as that in the Netherlands. - Although U.S. adolescents are no more sexually active than their counterparts in the Netherlands, their adolescent pregnancy rate is dramatically higher. - In the United States, 82 percent of pregnancies to mothers 15 to 19 years of age are unintended. - A cross-cultural comparison found that among 21 countries, the United States had the highest adolescent pregnancy rate among 15- to 19-year-olds and Switzerland the lowest - Despite the negative comparisons of the United States with many other developed countries, there have been some encouraging trends in U.S. adolescent pregnancy rates. - In 2015, the U.S. birth rate for 15- to 19-year-olds was 22.3 births per 1,000 females, the lowest rate ever recorded, which represents a dramatic decrease from the 61.8 births per 1,000 females in the same age range in 1991, and down even 4 percent since 2014. - There also has been a substantial decrease in adolescent pregnancies across ethnic groups in recent years. - Reasons for the decline include school/community health classes, increased contraceptive use, and fear of sexually transmitted infections such as AIDS.

hypothetical-deductive reasoning

Adolescents also think more logically. - Children are likely to solve problems through trial and error, while adolescents begin to think more as a scientist does, devising plans to solve problems and systematically testing solutions. - This type of problem solving requires hypothetical-deductive reasoning, which involves creating a hypothesis and deducing its implications, which provides ways to test the hypothesis. - Thus, formal operational thinkers develop hypotheses about ways to solve problems and then systematically deduce the best path to follow to solve the problem.

Early and Late Maturation Differences in Males

Adolescents who mature earlier or later than their peers perceive themselves differently. - In the Berkeley Longitudinal Study some years ago, early-maturing boys perceived themselves more positively and had more successful peer relations than did their late-maturing counterparts. - When the late-maturing boys were in their thirties, however, they had developed a stronger sense of identity than the early-maturing boys had. - This may have occurred because the late-maturing boys had more time to explore life's options, or because the early-maturing boys continued to focus on their advantageous physical status instead of on career development and achievement. - More recent research confirms, though, that at least during adolescence it is advantageous to be an early-maturing rather than a late-maturing boy

What are adolescence exercise levels associated with?

Adolescents' exercise levels are increasingly being found to be associated with parenting, peer relationships, and screen-based activity. - One study revealed that family meals during adolescence reduced the likelihood of being overweight or obese in adulthood. - Peers often influence adolescents' physical activity. - For example, researchers found that female adolescents' physical activity was linked to their male and female friends' physical activity, while male adolescents' physical activity was associated with their female friends' physical activity. - Higher screen time is also linked to adolescents engaging in less exercise as well as being overweight or obese. - Further, a recent study of U.S. eighth-, tenth-, and twelfth-graders from 1991 to 2016 found that psychological well-being (assessed with indicators of self-esteem, life satisfaction, and happiness) abruptly decreased after 2012. - In this study, adolescents who spent more time on electronic communication devices and screens (social media, the Internet, texting, and gam-ing) and less time on nonscreen activities (in-person social interaction, sports/exercise, homework, and attending religious services) had lower psychological well-being.

In what ethnic group is anorexia nervosa most common?

Although anorexia nervosa can be present in individuals from any ethnic group, most individuals with anorexia are non-Latina White adolescent or young adult females from well-educated, middle- and upper-income families and are competitive and high-achieving. - Individuals with anorexia nervosa often set high standards, become stressed about not being able to reach these standards, and are intensely concerned about how others perceive them. - Unable to meet these high expectations, they turn to something they can control—their weight. - Offspring of mothers with anorexia nervosa are at risk for becoming anorexic themselves. - Problems in family functioning are increasingly being found to be linked to the appearance of anorexia nervosa in adolescent girls, and family therapy is often recommended as an effective treatment for adolescent girls with anorexia nervosa

Influences that affect the life trajectory of adolescent children

Although most adolescents negotiate the lengthy path to adult maturity successfully, too large a group does not. - Ethnic, cultural, gender, socioeconomic, age, and lifestyle differences influence the actual life trajectory of each adolescent. - Different portrayals of adolescence emerge, depending on the particular group of adolescents being described. - Today's adolescents are exposed to a complex menu of lifestyle options through the media, and many face the temptations of drug use and sexual activity at increasingly young ages. - Too many adolescents are not provided with adequate opportunities and support to become competent adults

Adolescence and Sexual Identity

An adolescent's sexual identity involves activities, interests, styles of behavior, and an indication of sexual orientation (whether an individual has same-sex or other-sex attractions). - For example, some adolescents have a high anxiety level about sex, others a low level. - Some adolescents are strongly aroused sexually, others less so. - Some adolescents are very active sexually, others not at all. - Some adolescents are sexually inactive in response to their strong religious upbringing; others go to church regularly, yet their religious training does not inhibit their sexual activity

When does anorexia nervosa typically begin?

Anorexia nervosa typically begins in the early to middle adolescent years, often following an episode of dieting and some type of life stress. - It is about 10 times more likely to occur in females than males. - When anorexia nervosa does occur in males, the symptoms and other characteristics (such as a distorted body image and family conflict) are usually similar to those reported by females who have the disorder

Changes in the limbic system

At a lower, subcortical level, the limbic system, which is the seat of emotions and where rewards are experienced, matures much earlier than the prefrontal cortex and is almost completely developed by early adolescence. - The limbic system structure that is especially involved in emotion is the amygdala.

The effects of biology and culture on anorexia nervosa

Biology and culture are involved in anorexia nervosa. Genes play an important role in anorexia nervosa. - Also, the physical effects of dieting may change neural networks and thus sustain the disordered pattern. - The U.S. perception that thinness is fashionable likely contributes to the incidence of anorexia nervosa. - The media portray thin as beautiful in their choice of fashion models, whom many adolescent girls strive to emulate. - Social media also influence the pursuit of thin-ness. A recent study found that having an increase in Facebook friends across two years was linked to enhanced motivation to be thin

Early Maturation Differences in females

By contrast, an increasing number of researchers have found that early maturation increases girls' vulnerability to a number of problems. - Early-maturing girls are more likely to smoke, drink, be depressed, have an eating disorder, struggle for earlier independence from their parents, and have older friends; and their bodies are likely to elicit responses from males that lead to earlier dating and earlier sexual experiences. - In a recent study, onset of menarche before 11 years of age was linked to a higher incidence of distress disorders, fear disorders, and externalizing disorders in females. - Further, researchers recently found that early-maturing girls had higher rates of depression and antisocial behavior as middle-aged adults mainly because their difficulties began in adolescence and did not lessen over time. - In another study, early menarche was associated with risky sexual behavior in Korean females. - Researchers also have found that early-maturing girls tend to engage in sexual intercourse earlier and have more unstable sexual relationships. - Further, a study revealed that early-maturing Chinese girls and boys engaged in delinquency more than their on-time or late-maturing counterparts. - Another study found that early maturation predicted a stable higher level of depression for adolescent girls. - Also, a recent study indicated that early-maturing girls are at increased risk for physical and verbal abuse in dating. - In addition, early-maturing girls are less likely to graduate from high school, and they tend to cohabit and marry earlier

Cognitive Control

Cognitive control involves effective control in a number of areas, including controlling attention, reducing interfering thoughts, and being cognitively flexible. - Cognitive control continues to increase in adolescence and emerging adulthood

Deanna Kuhn

Deanna Kuhn (2009) discussed some important characteristics of adolescents' information processing and thinking. - In her view, in the later years of childhood and continuing in adolescence, individuals approach cognitive levels that may or may not be achieved, in contrast with the largely universal cognitive levels that young children attain. - By adolescence, considerable variation in cognitive functioning is present across individuals. - This variability supports the argument that adolescents are producers of their own development to a greater extent than are children. - That is, adolescents are more likely than children to initiate changes in thinking rather than depend on others, such as parents and teachers, to direct their thinking.

What discoveries did Piaget provide?

Despite these challenges to Piaget's ideas, we owe him a tremendous debt. - Piaget was the founder of the present field of cognitive development, and he developed a long list of masterful concepts of enduring power and fascination: assimilation, accommodation, object permanence, egocentrism, conservation, and others. - Psychologists also owe him the current vision of children as active, constructive thinkers. - And they are indebted to him for creating a theory that has generated a huge volume of research on children's cognitive development. - Piaget was a genius when it came to observing children. His careful observations demonstrated inventive ways to discover how children act on, and adapt to, their world. - Children need to make their experiences fit their schemes yet simultaneously adapt their schemes to reflect their experience. - Piaget revealed how cognitive change is likely to occur if the context is structured to allow gradual movement to the next higher level. - Concepts do not emerge suddenly, full-blown, but instead develop through a series of partial accomplishments that lead to increasingly comprehensive understanding

What are the positive outcomes that come from exercise in adolescence?

Exercise is linked to a number of positive physical outcomes in adolescence. - Regular exercise has a positive effect on adolescents' weight status. - Other positive health outcomes of exercise in adolescence are reduced triglyceride levels, lower blood pressure, and a lower incidence of type II diabetes. - Also in a recent study, an exercise program of 180 minutes per week improved the sleep patterns of obese adolescents. - Further, a recent study of adolescents with major depressive disorder (MDD) revealed that engaging in aerobic exercise for 12 weeks lowered their depressive symptoms. - And in a recent large-scale study of Dutch adolescents, physically active adolescents had fewer emotional and peer problems. - Further, in a recent research review, among a number of cognitive factors, memory was the factor that most often was improved by exercise in adolescence

Gender differences and body image

Gender differences characterize adolescents' perceptions of their bodies. In general, girls are less happy with their bodies and have more negative body images than boys throughout puberty - Girls' more negative body images may be due to media portrayals of the attractiveness of being thin, coupled with the increased levels of body fat in girls during puberty. - In a recent U.S. study of young adolescents, boys had a more positive body image than girls did (Morin & others, 2017). - Also, another study found that both boys' and girls' body images became more positive as they moved from the beginning to the end of adolescence

Reducing Adolescent Pregnancy

Girls Inc. offers four programs that are intended to increase adolescent girls' motivation to avoid pregnancy until they are mature enough to make responsible decisions about motherhood. - Growing Together, a series of five two-hour workshops for adolescent girls and their mothers, and Will Power/Won't Power, a series of six two-hour sessions that focus on assertiveness training, are designed for 12- to 14-year-old girls. - For older adolescent girls, Taking Care of Business provides nine sessions that emphasize career planning and provide information about sexuality, reproduction, and contraception. - The program Health Bridge coordinates health and educational services—girls can participate in this program as one of their Girls Inc. club activities. - Girls who participated in these programs were less likely to get pregnant than girls who did not participate

G. Stanley Hall "storm and stress" view

In 1904, G. Stanley Hall proposed the "storm-and-stress" view that adolescence is a turbulent time charged with conflict and mood swings. - However, when Daniel Offer and his colleagues (1988) studied the self-images of adolescents in a number of countries, at least 73 percent of the adolescents displayed a healthy self-image rather than attitudes of storm-and-stress.

What percentage of U.S. adolescents receive formal instruction in sexual health?

In 2011 to 2013, more than 80 percent of 15- to 19-year-olds were given information about STIs, HIV/AIDS, or how to say no to sex. - However, only 55 percent of males and 60 percent of females in this age range had received information about birth control. - Sexual health information also is more likely to be taught in high school than in middle school

What is the current profile of sexual activity of adolescents?

In a U.S. national survey conducted in 2015, 58 percent of twelfth-graders reported having experienced sexual intercourse, compared with 24 percent of ninth-graders. - By age 20, 77 percent of U.S. youth report having engaged in sexual intercourse - Nationally, 46 percent of twelfth-graders, 33.5 percent of eleventh-graders, 25.5 percent of tenth-graders, and 16 percent of ninth-graders recently reported that they were currently sexually active

The taste and manners of adolescent children

In matters of taste and manners, the young people of every generation have seemed unnervingly radical and different from adults— different in how they look, in how they behave, in the music they enjoy, in their hairstyles, and in the clothing they choose. - It would be an enormous error, though, to confuse adolescents' enthusiasm for trying on new identities and enjoying moderate amounts of outrageous behavior with hostility toward parental and societal standards. - Acting out and boundary testing are time-honored ways in which adolescents move toward accepting, rather than rejecting, parental values.

Timing and Variations in Puberty in the US vs the rest of the world

In the United States—where children mature up to a year earlier than children in European countries—the average age of menarche has declined significantly since the mid-nineteenth century. - Also, recent studies in Korea and Japan, China, and Saudi Arabia found that pubertal onset has been occurring earlier in recent years. - Fortunately, however, we are unlikely to see pubescent toddlers, since what has happened in the past century is likely the result of improved nutrition and health

Executive Function (Kuhn)

Kuhn (2009) argues that the most important cognitive change in adolescence is improvement in executive function, an umbrella-like concept that consists of a number of higher-level cognitive processes linked to the development of the prefrontal cortex. - Executive function involves managing one's thoughts to engage in goal-directed behavior and to exercise self-control. - Our further coverage of executive function in adolescence focuses on cognitive control and decision making.

Developing a sexual identity involves

Learning to manage sexual feelings Developing new forms of intimacy Learning skills to regulate sexual behavior

Risk factors in adolescent sexual behavior

Many adolescents are not emotionally prepared to handle sexual experiences, especially in early adolescence . - A recent study found that early sexual debut (first sexual intercourse before age 13) was associated with sexual risk taking, substance use, violent victimization, and suicidal thoughts/attempts in both sexual minority (gay, lesbian, and bisexual adolescents) and heterosexual youth. - Also, in a recent study of Korean adolescent girls, early menarche was linked with earlier initiation of sexual intercourse

When do people make the best decisions?

Most people make better decisions when they are calm than when they are emotionally aroused. - That may especially be true for adolescents, who have a tendency to be emotionally intense. - The same adolescent who makes a wise decision when calm may make an unwise decision when emotionally aroused

Negative stereotyping of adolescent children in the media

Negative stereotyping of adolescence has been extensive. - However, much of the negative stereotyping has been fueled by media reports of a visible minority of adolescents. - In the last decade there has been a call for adults to have a more positive attitude toward youth and emphasize their positive development. - Indeed, researchers have found that a majority of adolescents are making the transition from childhood through adolescence to adulthood in a positive way. - For example, a recent study of non-Latino White and African American 12- to 20-year-olds in the United States found that they were characterized much more by positive than problematic development, even during their most vulnerable times. - Their engagement in healthy behaviors, supportive relationships with parents and friends, and positive self-perceptions were much stronger than their angry and depressed feelings.

body image in adolescence

One psychological aspect of physical change in puberty is certain: - Adolescents are preoccupied with their bodies and develop images of what their bodies are like. - One study revealed that adolescents with the most positive body images engaged in health-enhancing behaviors, especially regular exercise

Might social media such as Facebook serve as an amplification tool for adolescent egocentrism?

One study found that Facebook usage does indeed increase self-interest. - A recent meta-analysis concluded that a greater use of social networking sites was linked to a higher level of narcissism

School Start Time and Sleep

One study found that just a 30-minute delay in school start time was linked to improvements in adolescents' sleep, alertness, mood, and health. - In another study, early school start times were linked to a higher vehicle crash rate in adolescent drivers. - The American Academy of Pediatrics has recommended that schools institute start times from 8:30 to 9:30 a.m. to improve adolescents' academic performance and quality of life

When does bulimia nervosa emerge?

One to 2 percent of U.S. women develop bulimia nervosa, and about 90 percent of people with bulimia are women. - Bulimia nervosa typically begins in late adolescence or early adulthood. - Many women who develop bulimia nervosa were somewhat over-weight before the onset of the disorder, and the binge eating often began during an episode of dieting. - About 70 percent of individuals who develop bulimia nervosa eventually recover from the disorder. - Like anorexics, bulimics are highly perfectionistic. - Drug therapy and psychotherapy have been effective in treating bulimia nervosa , and cognitive behavior therapy has been especially helpful

Parent influence on substance abuse in adolescence

Parents play an important role in preventing adolescent drug abuse. - Researchers have found that parental monitoring is linked with a lower incidence of problem behavior by adolescents, including substance abuse. - In a recent meta-analysis of parenting factors involved in adolescent alcohol use, higher levels of parental monitoring, support, and involvement were associated with a lower risk of adolescent alcohol misuse - Further, a research review found that when adolescents ate dinner more often with their families they were less likely to have problems such as substance abuse. - And research revealed that authoritative parenting was linked to lower rates of adolescent alcohol consumption, while parent-adolescent conflict was related to higher levels of adolescent alcohol use

Piaget's Theory

Piaget proposed that around 7 years of age children enter the concrete operational stage of cognitive development. - They can reason logically about concrete events and objects, and they make gains in their ability to classify objects and to reason about the relationships between classes of objects. - Around age 11, according to Piaget, the fourth and final stage of cognitive development—the formal operational stage—begins.

Challenging piaget's theory

Researchers have challenged some of Piaget's ideas regarding the formal operational stage. - Among their findings is that there is much more individual variation than Piaget envisioned: Only about one in three young adolescents is a formal operational thinker, and many American adults never become formal operational thinkers; neither do many adults in other cultures. - Furthermore, education in the logic of science and mathematics pro-motes the development of formal operational thinking. - This point recalls a criticism of Piaget's theory: Culture and education exert stronger influences on cognitive development than Piaget argued. - Piaget's theory of cognitive development has been challenged on other points as well. -Piaget conceived of stages as unitary structures of thought, with various aspects of a stage emerging at the same time. - However, most contemporary developmentalists agree that cognitive development is not as stage-like as Piaget thought. - Furthermore, children can be trained to reason at a higher cognitive stage, and some cognitive abilities emerge earlier than Piaget thought. - For instance, some understanding of the conservation of number has been demonstrated as early as age 3, although Piaget did not think it emerged until age 7. - Other cognitive abilities can emerge later than Piaget thought

Robert Crosnoe's (2011) book Fitting In, Standing Out

Robert Crosnoe's (2011) book, Fitting In, Standing Out, highlighted another major problem with U.S. high schools: how the negative social aspects of adolescents' lives undermine their academic achievement. - Adolescents become immersed in complex peer group cultures that demand conformity. - High school is supposed to be about getting an education, but in reality for many youth it is more about navigating the social worlds of peer relations that may or may not value education and academic achievement. - Adolescents who fail to fit in, especially those who are obese or gay, become stigmatized. - Crosnoe recommends increased school counseling services, expanded extracurricular activities, and improved parental monitoring to reduce such problems. - One study revealed that immigrant adolescents who participated in extracurricular activities improved their academic achievement and increased their school engagement

Other factors associated with sexual risk taking

Socioeconomic status, peer relations, school performance, sports participation, and religious orientation provide further information about sexual risk taking by adolescents. - For example, the percentage of sexually active young adolescents is higher in low-income areas of inner cities. Also, one study found that adolescents who associated with more deviant peers in early adolescence were likely to have had more sexual partners by age 16. - And a research review found that school connectedness was linked to positive sexuality outcomes. - Also, a study of middle school students revealed that better academic achievement was a protective factor in delaying initiation of sexual intercourse. - Further, a recent study found that adolescent males who play sports engage in a higher level of sexual risk taking, while adolescent females who play sports engage in a lower level of sexual risk-taking. - And a recent study of African American adolescent girls indicated that those who reported that religion was of low or moderate importance to them had a much earlier sexual debut that their counterparts who said that religion was very or extremely important to them

Why do the changes of puberty occur when they do, and how can variations in their timing be explained?

The basic genetic program for puberty is wired into the species, but nutrition, health, family stress, and other environmental factors also affect puberty's timing and makeup. - A number of studies have found that higher weight, especially obesity, is linked to earlier pubertal development. - For example, a recent study concluded that earlier pubertal onset occurred in girls with a higher body mass index (BMI). - Further, a recent Chinese study also revealed that a higher BMI was associated with earlier pubertal onset. - Also, puberty comes earlier when girls and boys experience considerable stress and conflict. - For example, a recent study found that child sexual abuse was linked to earlier pubertal onset. - For most boys, the pubertal sequence may begin as early as age 10 or as late as 13½ and may end as early as age 13 or as late as 17. - Thus, the normal range is wide enough that, given two boys of the same chronological age, one might complete the pubertal sequence before the other one has begun it. - For girls, menarche is considered within the normal range if it appears between the ages of 9 and 15.

Nutrition in Adolescence

The eating habits of many adolescents are health-compromising, and an increasing number of adolescents have an eating disorder. - National data indicate that the percentage of overweight U.S. 12- to 19-year-olds increased from 11 percent in the early 1990s to 20.5 percent in 2014. - In another study, 12.4 percent of U.S. kindergarten children were obese and by 14 years of age, 20.8 percent were obese. - Being obese in adolescence predicts obesity in emerging adulthood. - For example, a longitudinal study of more than 8,000 adolescents found that obese adolescents were more likely to develop severe obesity in emerging adulthood than were overweight or normal-weight adolescents. - In another longitudinal study, the percentage of overweight individuals increased from 20 percent at 14 years of age to 33 percent at 24 years of age

Role of the Endocrine System in Puberty

The endocrine system's role in puberty involves the interaction of the hypothalamus, the pituitary gland, and the gonads. - The hypothalamus is a structure in the brain that monitors eating and sex. - The pituitary gland is an important endocrine gland that controls growth and regulates other glands; among these, the gonads—the testes in males, the ovaries in females—are particularly important in giving rise to pubertal changes in the body

The effect of the first year of middle school or junior high school on adolescents

The first year of middle school or junior high school can be difficult for many students. - In one study of the transition from sixth grade in an elementary school to seventh grade in a junior high school, adolescents' perceptions of the quality of their school life plunged in the seventh grade. - Compared with their earlier feelings as sixth-graders, the seventh-graders were less satisfied with school, were less committed to school, and liked their teachers less. - This occurred regardless of how academically successful the students were. - Further, a recent study found that teacher warmth was higher in the last four years of elementary school and then dropped in the middle school years. - The drop in teacher warmth was associated with lower student math scores.

imaginary audience

The imaginary audience is adolescents' belief that others are as interested in them as they themselves are, as well as attention-getting behavior—attempts to be noticed, visible, and "on stage." - For example, an eighth-grade boy might walk into the classroom thinking that all eyes are riveted on his spotty complexion. - Adolescents sense that they are "on stage" in early adolescence, believing they are the main actors and all others are the audience.

personal fable

The personal fable is the part of adolescent egocentrism involving a sense of uniqueness and invincibility (or invulnerability). - For example, a 13-year-old says about herself: "No one understands me, particularly my parents. They have no idea of what I am feeling." - Adolescents' sense of personal uniqueness makes them believe that no one can understand how they really feel. - As part of their effort to retain a sense of personal uniqueness, they might craft a story about the self that is filled with fantasy in a world that is far removed from reality. - Personal fables frequently show up in adolescent diaries.

Internet and Social Media effects on body image

The recent dramatic increase in Internet use, particularly social media platforms, has raised concerns about their influence on adolescents' body images - For example, a recent study of U.S. 12- to 14-year-olds found that heavier social media use was associated with body dissatisfaction. - Also, in a recent study of U.S. college women, spending more time on Facebook was related to more frequent body and weight concern comparisons with other women, more attention to the physical appearance of others, and more negative feelings about their own bodies. - In sum, various aspects of expo-sure to the Internet and social media are increasing the body dissatisfaction of adolescents and emerging adults, especially females.

Effect of Social Context on Decision Making

The social context plays a key role in adolescent decision making. - Adolescents' willingness to make risky decisions is more likely to occur in contexts where substances and other temptations are readily available. - And the presence of peers in risk-taking situations increases the likelihood that adolescents will make risky decisions. - In a recent study, adolescents took greater risks and showed stronger preference for immediate rewards when they were with three same-aged peers than when they were alone

Leading Causes of Death in Adolescence

The three leading causes of death in adolescence are unintentional injuries, homicide, and suicide - Almost half of all deaths occurring from 15 to 24 years of age are due to unintentional injuries, the majority of them involving motor vehicle accidents. - Risky driving habits, such as speeding, tailgating, and driving under the influence of alcohol or other drugs, may be more important contributors to these accidents than lack of driving experience. - In about 50 percent of motor vehicle fatalities involving adolescents, the driver has a blood alcohol level of 0.10 percent—twice the level needed to be designated as "under the influence" in some states. - An increasing concern is the growing number of adolescents who mix alcohol and energy drinks, a practice that is linked with risky driving. - A high rate of intoxication is also found in adolescents who die as pedestrians or while using recreational vehicles. - Homicide is the second-leading cause of death in adolescence, especially among African American male adolescents. - The rate of the third-leading cause, adolescent suicide, has tripled since the 1950s. - Suicide accounts for 6 percent of deaths in the 10-to-14 age group and 12 percent of deaths in the 15-to-19 age group.

The problems in the transition to high school

The transition to high school can have problems, just as the transition to middle school can. - These problems may include the following: high schools are often even larger, more bureaucratic, and more impersonal than middle schools are; there isn't much opportunity for students and teachers to get to know each other, which can lead to distrust; and teachers too infrequently make content relevant to students' interests. - Such experiences likely undermine the motivation of students.

Effective Schools for Young Adolescents

There are continuing calls for improving middle school education. - Educators and psychologists worry that junior high and middle schools have become watered-down versions of high schools, mimicking their curricular and extracurricular schedules. - Critics argue that these schools should offer activities that reflect a wide range of individual differences in biological and psychological development among young adolescents. - Expressing these concerns, the Carnegie Council on Adolescent Development (1989) issued an extremely negative evaluation of U.S. middle schools. - It concluded that most young adolescents attended massive, impersonal schools; were taught from irrelevant curricula; trusted few adults in school; and lacked access to health care and counseling. - It recommended that the nation develop smaller "communities" or "houses" to lessen the impersonal nature of large middle schools, maintain lower student-to-counselor ratios (10 to 1 instead of several hundred to 1), involve parents and community leaders in schools, develop new curricula, have teachers team teach in more flexibly designed curriculum blocks that integrate several disciplines, boost students' health and fitness with more in-school programs, and help students who need public health care to get it. - Almost three decades later, experts were still finding that middle schools throughout the nation would require a major redesign to become effective in educating adolescents

Positive aspects of the Transition to Middle or Junior High School

There can also be positive aspects to this transition. - Students are more likely to feel grown up, have more subjects from which to select, feel more challenged intellectually by academic work, have more opportunities to spend time with peers and locate compatible friends, and enjoy increased independence from direct parental monitoring.

Puberty and its effect on neurotransmitters

With the onset of puberty, the levels of neurotransmitters change. - For example, an increase in the neurotransmitter dopamine occurs in both the prefrontal cortex and the limbic system during adolescence. - Increases in dopamine have been linked to increased risk taking and use of addictive drugs. - Researchers have also found that dopamine plays an important role in reward seeking during adolescence

The Problem of Students Dropping out of School

Yet another concern about U.S. high schools involves students dropping out of school. - In the last half of the twentieth century and the first decade of the twenty-first century, U.S. high school dropout rates declined. - In the 1940s, more than half of U.S. 16- to 24-year-olds had dropped out of school; by 2015, this figure had decreased to 5.9 percent. - The dropout rate of Latino adolescents remains high, although it has been decreasing considerably in the twenty-first century (from 27.8 percent in 2000 to 9.2 percent in 2016). - The lowest dropout rate in 2015 was for Asian American adolescents (2.1 percent), followed by non-Latino White adolescents (4.6 percent), African American adolescents (6.5 percent), and Latino adolescents (9.2 percent). - Gender differences in U.S. school dropout rates have been narrowing, but males were still slightly more likely to drop out than females in 2015 (6.3 percent versus 5.4 percent) - National data on Native American adolescents are inadequate because statistics have been collected sporadically and/or from small samples. - However, there are some indications that this group may have the highest dropout rate. - Also, the average U.S. high school dropout rates mask some very high dropout rates in low-income areas of inner cities. - For example, in Detroit, Cleveland, and Chicago, dropout rates are higher than 50 percent. - Also, the percentages cited earlier are for 16- to 24-year-olds. - When dropout rates are calculated in terms of students who do not graduate from high school within four years, the percentages are much higher. - Thus, in considering high school dropout rates, it is important to examine age, the number of years it takes to complete high school, and various contexts including ethnicity, gender, and location.

Bulimia nervosa

is an eating disorder in which the individual consistently follows a binge-and-purge pattern, periodically overeating and then engaging in self-induced vomiting or use of laxatives. - According to the DSM-5 classification system, an individual with bulimia nervosa is characterized by: 1) eating in a specific amount of time (such as within a 2-hour time frame) an amount of food that is larger than what most people would eat in a similar period in similar circumstances, and 2) a lack of control over eating during an episode. - Although many people binge and purge occasion-ally, a person is considered to have a serious bulimic disorder if the episodes occur at least twice a week for three months. - Most people with bulimia are preoccupied with food, have a strong fear of becoming overweight, are depressed or anxious, and have a distorted body image. - Bulimics may have difficulty controlling their emotions. - Unlike people who have anorexia, people who binge and purge typically fall within a normal weight range, which makes bulimia more difficult to detect.

Anorexia nervosa

is an eating disorder that involves the relentless pursuit of thinness through starvation. It is a serious disorder that can lead to death - According to the psy-chiatric classification system, DSM-5, individuals have anorexia nervosa when there is: 1) a restriction in energy intake leading to significantly low body weight; 2) a presence of intense fear of gaining weight or becoming fat or a persistent behavior that interferes with gaining weight; and 3) a disturbance in how body weight or shape is experienced or lack of recognition of how serious the current low weight is. - Obsessive thinking about weight and compulsive exercise also are linked to anorexia nervosa. - Even when they are extremely thin, individuals with this eating disorder see themselves as too fat. - They never think they are thin enough, especially in the abdomen, buttocks, and thighs. - They usually weigh themselves frequently, often take their body measurements, and gaze critically at themselves in mirror

The hormone-behavior link

one research review concluded that there is insufficient quality research to confirm that changing testosterone levels during puberty are linked to mood and behavior in adolescent males. - Thus, hormonal effects by themselves do not account for adolescent development. - For example, in one study, social factors accounted for two to four times as much variance as did hormonal factors in young adolescent girls' depression and anger. - Behavior and moods also can affect hormones. - Stress, eating patterns, exercise, sexual activity, tension, and depression can activate or suppress various aspects of the hormonal system.