adolescence

• n.

• 青年期、思春期

関

adolescent、pubertal、puberty、pubescence、pubescent、teenager、young adulthood、youth

　 　 　

WordNet

1. in the state that someone is in between puberty and adulthood
2. the time period between the beginning of puberty and adulthood
3. the time of life when sex glands become functional (同)pubescence
4. a juvenile between the onset of puberty and maturity (同)stripling, teenager, teen
5. relating to or peculiar to or suggestive of an adolescent; "adolescent problems"
6. displaying or suggesting a lack of maturity; "adolescent insecurity"; "jejune responses to our problems"; "their behavior was juvenile"; "puerile jokes" (同)jejune, juvenile, puerile
7. being of the age 13 through 19; "teenage mothers"; "the teen years" (同)teen, teenage, teenaged
8. in the state of development between puberty and maturity; "adolescent boys and girls"
9. an early period of development; "during the youth of the project" (同)early days
10. early maturity; the state of being young or immature or inexperienced
11. the time of life between childhood and maturity
12. the freshness and vitality characteristic of a young person (同)youthfulness, juvenility
13. (of animals especially human beings) having arrived at the onset of puberty (the age at which sex glands become functional) but not yet fully mature; "the budding breasts of a pubescent girl and the downy chin of pubescent boy"
14. of or related to puberty

PrepTutorEJDIC

1. 青春期,思春期
2. (受胎能力が生じる)思春期,年ごろ
3. 青春期の,青年らしい / 青春期の人,若者
4. 〈U〉『若さ』,年の若いこと;若々しさ,元気 / 〈U〉『青年時代』,青春[期];(時代などの)初期 / 〈C〉《しばしば軽べつして》『青年』,若者,(特に)若い男 / 〈U〉《集合的に》《単数・複数扱い》《文》青年,若者たち(young people)
5. 思春期の,年ごろの / (動植物が)羽毛(綿毛)におおわれた

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出典(authority):フリー百科事典『ウィキペディア（Wikipedia）』「2012/09/02 15:11:20」(JST)

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"Teen" and "teenagers" redirect here. For other uses, see Teen (disambiguation).

"Adolescents" redirects here. For Redirect, see Adolescent Psychology. For the band, see Adolescents (band). For the song by Incubus, see Adolescents (song).

For the 1966 French documentary, see Adolescence (film).

Adolescence (from Latin: adolescere meaning "to grow up") is a transitional stage of physical and psychological human development generally occurring between puberty and legal adulthood (age of majority). The period of adolescence is most closely associated with the teenage years, although its physical, psychological and cultural expressions can begin earlier and end later. For example, although puberty has been historically associated with the onset of adolescent development, it now typically begins prior to the teenage years and there has been a normative shift of it occurring in preadolescence, particularly in females (see early and precocious puberty). Physical growth, as distinct from puberty (particularly in males), and cognitive development generally seen in adolescence, can also extend into the early twenties. Thus chronological age provides only a rough marker of adolescence, and scholars have found it difficult to agree upon a precise definition of adolescence. A thorough understanding of adolescence in society depends on information from various perspectives, most importantly from the areas of psychology, biology, history, sociology, education, and anthropology. Within all of these perspectives, adolescence is viewed as a transitional period between childhood and adulthood whose cultural purpose is the preparation of children for adult roles.

The end of adolescence and the beginning of adulthood varies by country and by function, and furthermore even within a single nation-state or culture there can be different ages at which an individual is considered to be (chronologically and legally) mature enough to be entrusted by society with certain tasks. Such milestones include, but are not limited to, driving a vehicle, having legal sexual relations, serving in the armed forces or on a jury, purchasing and drinking alcohol, voting, entering into contracts, completing certain levels of education, and marriage. Adolescence is usually accompanied by an increased independence allowed by the parents or legal guardians and less supervision, contrary to the preadolescence stage.

In popular culture, many adolescent characteristics are attributed to physical changes and raging hormones. There is little evidence that this is the case, however. In studying adolescent development, adolescence can be defined biologically, as the physical transition marked by the onset of puberty and the termination of physical growth; cognitively, as changes in the ability to think abstractly and multi-dimensionally; or socially, as a period of preparation for adult roles. Major pubertal and biological changes include changes to the sex organs, height, weight, and muscle mass, as well as major changes in brain structure and organization. Cognitive advances encompass both increases in knowledge and in the ability to think abstractly and to reason more effectively. The study of adolescent development often involves interdisciplinary collaborations. For example, researchers in neuroscience or bio-behavioral health might focus on pubertal changes in brain structure and its effects on cognition or social relations. Sociologists interested in adolescence might focus on the acquisition of social roles (e.g., worker or romantic partner) and how this varies across cultures or social conditions. Developmental psychologists might focus on changes in relations with parents and peers as a function of school structure and pubertal status.

History

See also: Adult#Biological adulthood

Historical perspectives such as those offered by Glen Elder, Joseph Kett, or Thomas Hine stress the fact that adolescence as a developmental period has varied considerably from one historical era to another. Because of its ever-changing nature, it is impossible to generalize about issues such as the degree to which adolescence is stressful, the developmental tasks of the period, or the nature of intergenerational relationships. One group of theorists, called inventionists, argue that adolescence is entirely a social invention, and that the way in which we divide the life cycle into stages is nothing more than a reflection of the political, economic and social circumstances in which we live. According to this group, although puberty has been a feature of development for as long as humans have lived, it was not until the rise of obligatory education that we began treating adolescents as a distinct group. According to C.P. Snow, who spoke about two cultures - the cultures of science and humanities, is stated that most scientists know little about modern age. He also stated that in the past things have been different.

Biological development

Puberty

General

Main article: Puberty

Upper body of teenage boy. The structure has changed to resemble an adult form.

Puberty is a period of several years in which rapid physical growth and psychological changes occur, culminating in sexual maturity. The average onset of puberty is at 10 or 11 for girls and age 12 or 13 for boys. Every person's individual timetable for puberty is influenced primarily by heredity, although environmental factors, such as diet and exercise, also exert some influence. These factors can also contribute to precocious and delayed puberty.

Some of the most significant parts of pubertal development involve distinctive physiological changes in individuals' height, weight, body composition, and circulatory and respiratory systems. These changes are largely influenced by hormonal activity. Hormones play an organizational role, priming the body to behave in a certain way once puberty begins, and an activational role, referring to changes in hormones during adolescence that trigger behavioral and physical changes.

Puberty begins with a surge in hormone production, which in turn causes a number of physical changes. It is also the stage of life in which a child develops secondary sex characteristics (for example, a deeper voice and larger adam's apple in boys, and development of breasts and more curved and prominent hips in girls) as his or her hormonal balance shifts strongly towards an adult state. This is triggered by the pituitary gland, which secretes a surge of hormonal agents into the blood stream, initiating a chain reaction. The male and female gonads are subsequently activated, which puts them into a state of rapid growth and development; the triggered gonads now commence the mass production of the necessary chemicals. The testes primarily release testosterone, and the ovaries predominantly dispense estrogen. The production of these hormones increases gradually until sexual maturation is met. Some boys may develop gynecomastia due to an imbalance of sex hormones, tissue responsiveness or obesity.

Facial hair in males normally appears in a specific order during puberty: The first facial hair to appear tends to grow at the corners of the upper lip, typically between 14 to 16 years of age. It then spreads to form a moustache over the entire upper lip. This is followed by the appearance of hair on the upper part of the cheeks, and the area under the lower lip. The hair eventually spreads to the sides and lower border of the chin, and the rest of the lower face to form a full beard. As with most human biological processes, this specific order may vary among some individuals. Facial hair is often present in late adolescence, around ages 17 and 18, but may not appear until significantly later. Some men do not develop full facial hair for 10 years after puberty. Facial hair will continue to get coarser, darker and thicker for another 2–4 years after puberty.

The major landmark of puberty for males is the first ejaculation, which occurs, on average, at age 13. For females, it is menarche, the onset of menstruation, which occurs, on average, between ages 12 and 13. The age of menarche is influenced by heredity, but a girl's diet and lifestyle contribute as well. Regardless of genes, a girl must have certain proportion of body fat to attain menarche. Consequently, girls who have a high-fat diet and who are not physically active begin menstruating earlier, on average, than girls whose diet contains less fat and whose activities involve fat reducing exercise (e.g. ballet and gymnastics). Girls who experience malnutrition or are in societies in which children are expected to perform physical labor also begin menstruating at later ages.

The timing of puberty can have important psychological and social consequences. Early maturing boys are usually taller and stronger than their friends. They have the advantage in capturing the attention of potential partners and in becoming hand-picked for sports. Pubescent boys often tend to have a good body image, are more confident, secure, and more independent. Late maturing boys can be less confident because of poor body image when comparing themselves to already developed friends and peers. However, early puberty is not always positive for boys; early sexual maturation in boys can be accompanied by increased aggressiveness due to the surge of hormones that affect them. Because they appear older than their peers, pubescent boys may face increased social pressure to conform to adult norms; society may view them as more emotionally advanced, despite the fact that their cognitive and social development may lag behind their appearance. Studies have shown that early maturing boys are more likely to be sexually active and are more likely to participate in risky behaviors.

For girls early maturation can sometimes lead to increased self-consciousness, though a typical aspect in maturing females. Because of their bodies' developing in advance, pubescent girls can become more insecure. Consequently, girls that reach sexual maturation early are more likely than their peers to develop eating disorders. Nearly half of all American high school girls' diet is to lose weight. In addition, girls may have to deal with sexual advances from older boys before they are emotionally and mentally mature. In addition to having earlier sexual experiences and more unwanted pregnancies than late maturing girls, early maturing girls are more exposed to alcohol and drug abuse. Those who have had such experiences tend to perform less well in school than their "inexperienced" age peers.

Girls have usually reached full physical development by ages 15–17, while boys usually complete puberty by ages 16–18. Any increase in height beyond the post-pubertal age is uncommon. Girls attain reproductive maturity about 4 years after the first physical changes of puberty appear. In contrast, boys accelerate more slowly but continue to grow for about 6 years after the first visible pubertal changes.

Approximate outline of development periods in child and teenager development. Adolescence is marked in red at top right.

Growth spurt

The adolescent growth spurt is a rapid increase in individuals' height and weight during puberty resulting from the simultaneous release of growth hormones, thyroid hormones, and androgens. Males experience their growth spurt about two years later, on average, than females. During their peak height velocity (the time of most rapid growth), adolescents grow at a growth rate nearly identical to that of a toddler—about 4 inches (10.3 cm) a year for males and 3.5 inches (9 cm) for females. In addition to changes in height, adolescents also experience a significant increase in weight (Marshall, 1978). The weight gained during adolescence constitutes nearly half of one's adult body weight. Teenage and early adult males may continue to gain natural muscle growth even after puberty.

The accelerated growth in different body parts happens at different times, but for all adolescents it has a fairly regular sequence. The first places to grow are the extremities—the head, hands and feet—followed by the arms and legs, then the torso and shoulders. This non-uniform growth is one reason why an adolescent body may seem to be out of proportion.

During puberty, bones become harder and more brittle. At the conclusion of puberty, the ends of the long bones close during the process called epiphysis. There are ethnic differences in these skeletal changes: bone density increases significantly more among African-American than white adolescents, which might account for decreased likelihood of African-American women developing osteoporosis and having fewer bone fractures.

Another set of significant physical changes during puberty happen in bodily distribution of fat and muscle. This process is different for females and males. Before puberty, there are nearly no sex differences in fat and muscle distribution; during puberty, boys grow muscle much faster than girls, although both sexes experience rapid muscle development. In contrast, though both sexes experience an increase in body fat, the increase much more significant for girls. Frequently, the increase in fat for girls happens in their years just before puberty. The ratio between muscle and fat among post-pubertal boys is around three to one, while for girls it is about five to four. This may help explain sex differences in athletic performance.

Pubertal development also affects circulatory and respiratory systems as an adolescents' heart and lungs increase in both size and capacity. These changes lead to increased strength and tolerance for exercise. Sex differences are apparent as males tend to develop "larger hearts and lungs, higher systolic blood pressure, a lower resting heart rate, a greater capacity for carrying oxygen to the blood, a greater power for neutralizing the chemical products of muscular exercise, higher blood hemoglobin and more red blood cells".

It is important to note that, despite some genetic sex differences, environmental factors play a large role in biological changes during adolescence. For example, girls tend to reduce their physical activity in preadolescence and may receive inadequate nutrition from diets that often lack important nutrients, such as iron. These environmental influences in turn affect female physical development.

Reproduction-related changes

Primary sex characteristics are those directly related to the sex organs. In males, the first stages of puberty involve growth of the testes and scrotum, followed by growth of the penis. At the time that the penis develops, the seminal vesicles, the prostate, and the bilbo-urethral glands also enlarge and develop. The first ejaculation of seminal fluid generally occurs about one year after the beginning of accelerated penis growth, although this is often determined culturally rather than biologically, since for many boys first ejaculation occurs as a result of masturbation. Boys are generally fertile before they have an adult appearance

In females, changes in the primary sex characteristics involve growth of the uterus, vagina, and other aspects of the reproductive system. Menarche, the beginning of menstruation, is a relatively late development which follows a long series of hormonal changes. Generally, a girl is not fully fertile until several years after menarche, as regular ovulation follows menarche by about two years. Unlike males, therefore, females usually appear physically mature before they are capable of becoming pregnant.

Changes in secondary sex characteristics include every change that is not directly related to sexual reproduction. In males, these changes involve appearance of pubic, facial, and body hair, deepening of the voice, roughening of the skin around the upper arms and thighs, and increased development of the sweat glands. In females, secondary sex changes involve elevation of the breast, widening of the hips, development of pubic and underarm hair, widening of the areolae, and elevation of the nipples.

The changes in secondary sex characteristics that take place during puberty are often referred to in terms of five Tanner stages, named after the British pediatrician who devised the categorization system.

Changes in the brain

The human brain is not fully developed by the time a person reaches puberty. Between the ages of 10 and 25, the brain undergoes changes that have important implications for behavior (see Cognitive development below).

The brain reaches 90% of its adult size by the time a person is six years of age. Thus, the brain does not grow in size much during adolescence. However, the creases in the brain continue to become more complex until the late teens. The biggest changes in the folds of the brain during this time occur in the parts of the cortex that process cognitive and emotional information.

Over the course of adolescence, the amount of white matter in the brain increases linearly, while the amount of grey matter in the brain follows an inverted-U pattern. Through a process called synaptic pruning, unnecessary neuronal connections in the brain are eliminated and the amount of grey matter is pared down. However, this does not mean that the brain loses functionality; rather, it becomes more efficient due to increased myelination (insulation of axons) and the reduction of unused pathways.

The first areas of the brain to be pruned are those involving primary functions, such as motor and sensory areas. The areas of the brain involved in more complex processes lose matter later in development. These include the lateral and prefrontal cortices, among other regions.

Some of the most developmentally significant changes in the brain occur in the prefrontal cortex, which is involved in decision-making and cognitive control, as well as other higher cognitive functions. During adolescence, myelination and synaptic pruning in the prefrontal cortex increases, improving the efficiency of information processing, and neural connections between the prefrontal cortex and other regions of the brain are strengthened. This leads to better evaluation of risks and rewards, as well as improved control over impulses. Specifically, developments in the dorsolateral prefrontal cortex are important for controlling impulses and planning ahead, while development in the ventromedial prefrontal cortex is important for decision making. Changes in the orbitofrontal cortex are important for evaluating rewards and risks.

Two neurotransmitters that play important roles in adolescent brain development are glutamate and dopamine. Glutamate is an excitatory neurotransmitter. During the synaptic pruning that occurs during adolescence, most of the neural connections that are pruned contain receptors for glutamate or other excitatory neurotransmitters. Because of this, by early adulthood the synaptic balance in the brain is more inhibitory than excitatory.

Dopamine is associated with pleasure and attuning to the environment during decision-making. During adolescence, dopamine levels in the limbic system increase and input of dopamine to the prefrontal cortex increases. The balance of excitatory to inhibitory neurotransmitters and increased dopamine activity in adolescence may have implications for adolescent risk-taking and vulnerability to boredom (see Cognitive development, below). Development in the limbic system plays an important role in determining rewards and punishments and processing emotional experience and social information. Changes in the levels of the neurotransmitters dopamine and serotonin in the limbic system make adolescents more emotional and more responsive to rewards and stress. The corresponding increase in emotional variability also can increase adolescents’ vulnerability.

Cognitive development

Adolescence is also a time for rapid cognitive development. Piaget describes adolescence as the stage of life in which the individual's thoughts start taking more of an abstract form and the egocentric thoughts decrease. This allows the individual to think and reason in a wider perspective. A combination of behavioural and fMRI studies have demonstrated development of executive functions, that is, cognitive skills that enable the control and coordination of thoughts and behaviour, which are generally associated with the prefrontal cortex. The thoughts, ideas and concepts developed at this period of life greatly influence one's future life, playing a major role in character and personality formation.

Biological changes in brain structure and connectivity within the brain interact with increased experience, knowledge, and changing social demands to produce rapid cognitive growth (see Changes in the brain above). The age at which particular changes take place will vary between individuals, but the changes discussed below generally begin at puberty or shortly thereafter and some skills continue to develop as the adolescent ages.

Theoretical perspectives

There are two perspectives on adolescent thinking. One is the constructivist view of cognitive development. Based on the work of Piaget, it takes a quantitative, state-theory approach, hypothesizing that adolescents’ cognitive improvement is relatively sudden and drastic. The second is the information-processing perspective, which derives from the study of artificial intelligence and attempts to explain cognitive development in terms of the growth of specific components of the thinking process.

Improvements in cognitive ability

By the time individuals have reached age 15 or so, their basic thinking abilities are comparable to those of adults. These improvements occur in five areas during adolescence:

1. Attention. Improvements are seen in selective attention, the process by which one focuses on one stimulus while tuning out another. Divided attention, the ability to pay attention to two or more stimuli at the same time, also improves.
2. Memory. Improvements are seen in both working memory and long-term memory.
3. Processing speed. Adolescents think more quickly than children. Processing speed improves sharply between age five and middle adolescence; it then begins to level off at age 15 and does not appear to change between late adolescence and adulthood.
4. Organization. Adolescents are more aware of their own thought processes and can use mnemonic devices and other strategies to think more efficiently.
5. Metacognition.

Hypothetical and abstract thinking

Adolescents' thinking is less bound to concrete events than that of children: they can contemplate possibilities outside the realm of what currently exists. One manifestation of the adolescent’s increased facility with thinking about possibilities is the improvement of skill in deductive reasoning, which leads to the development of hypothetical thinking. This provides the ability to plan ahead, see the future consequences of an action and to provide alternative explanations of events. It also makes adolescents more skilled debaters, as they can reason against a friend’s or parent’s assumptions. Adolescents also develop a more sophisticated understanding of probability.

The appearance of more systematic, abstract thinking is another notable aspect of cognitive development during adolescence. For example, adolescents find it easier than children to comprehend the sorts of higher-order abstract logic inherent in puns, proverbs, metaphors, and analogies. Their increased facility permits them to appreciate the ways in which language can be used to convey multiple messages, such as satire, metaphor, and sarcasm. (Children younger than age nine often cannot comprehend sarcasm at all). This also permits the application of advanced reasoning and logical processes to social and ideological matters such as interpersonal relationships, politics, philosophy, religion, morality, friendship, faith, democracy, fairness, and honesty.

Metacognition

A third gain in cognitive ability involves thinking about thinking itself, a process referred to as metacognition. It often involves monitoring one’s own cognitive activity during the thinking process. Adolescents’ improvements in knowledge of their own thinking patterns lead to better self-control and more effective studying. It is also relevant in social cognition, resulting in increased introspection, self-consciousness, and intellectualization (in the sense of thought about one’s own thoughts, rather than the Freudian definition as a defense mechanism). Adolescents are much better able than children to understand that people do not have complete control over their mental activity. Being able to introspect may lead to two forms of adolescent egocentrism, which results in two distinct problems in thinking: the imaginary audience and the personal fable. These likely peak at age fifteen, along with self-consciousness in general.

Related to metacognition and abstract thought, perspective-taking involves a more sophisticated theory of mind. Adolescents reach a stage of social perspective-taking in which they can understand how the thoughts or actions of one person can influence those of another person, even if they personally are not involved.

Relativistic thinking

Compared to children, adolescents are more likely to question others’ assertions, and less likely to accept facts as absolute truths. Through experience outside the family circle, they learn that rules they were taught as absolute are in fact relativistic. They begin to differentiate between rules instituted out of common sense—not touching a hot stove—and those that are based on culturally-relative standards (codes of etiquette, not dating until a certain age), a delineation that younger children do not make. This can lead to a period of questioning authority in all domains.

Wisdom

Wisdom, or the capacity for insight and judgment that is developed through experience, increases between the ages of fourteen and twenty-five, then levels off. Thus, it is during the adolescence-adulthood transition that individuals acquire the type of wisdom that is associated with age. Wisdom is not the same as intelligence: adolescents do not improve substantially on IQ tests since their scores are relative to others in their same age group, and relative standing usually does not change—everyone matures at approximately the same rate.

Risk-taking

In light of the fact that most injuries sustained by adolescents are related to risky behavior (car crashes, alcohol, unprotected sex), much research has been done on adolescent risk-taking, particularly on whether and why adolescents are more likely to take risks than adults. Behavioral decision-making theory says that adolescents and adults both weigh the potential rewards and consequences of an action. However, research has shown that adolescents seem to give more weight to rewards, particularly social rewards, than do adults.

During adolescence, there is an extremely high emphasis on approval of peers as a reward due to adolescents' increased self-consciousness. There may be evolutionary benefits to an increased propensity for risk-taking in adolescence—without risk-taking, teenagers would not have the motivation or confidence necessary to make the change in society from childhood to adulthood. It may also have reproductive advantages: adolescents have a newfound priority in sexual attraction and dating, and risk-taking is required to impress potential mates. Research also indicates that baseline sensation seeking may affect risk-taking behavior throughout the lifespan.

Social development

Identity development

Among the most common beliefs about adolescence is that it is the time when teens form their personal identities. Egocentrism is being performed by adolescents which then forms self-consciousness of wanting to feel important in their peer groups and having social acceptance of fitting into the group. Empirical studies suggest that this process might be more accurately described as identity development, rather than formation, but confirms a normative process of change in both content and structure of one’s thoughts about the self. Researchers have used three general approaches to understanding identity development: self-concept, sense of identity, and self-esteem. The years of adolescence, creates a more conscientious group of young adults. Adolescents pay close attention and give more time and effort to their appearance as their body goes through changes. Unlike children, teens put forth an effort to look presentable (1991).

Self-concept

See also: Self-concept

Early in adolescence, cognitive developments result in greater self-awareness, greater awareness of others and their thoughts and judgments, the ability to think about abstract, future possibilities, and the ability to consider multiple possibilities at once. As a result, adolescents experience a significant shift from the simple, concrete, and global self-descriptions typical of young children; as children, they defined themselves with physical traits whereas as adolescents, they define themselves based on their values, thoughts and opinions.

Adolescents can now conceptualize multiple "possible selves" they could become and long-term possibilities and consequences of their choices. Exploring these possibilities may result in abrupt changes in self-presentation as the adolescent chooses or rejects qualities and behaviors, trying to guide the actual self toward the ideal self (who the adolescent wishes to be) and away from the feared self (who the adolescent does not want to be). For many, these distinctions are uncomfortable, but they also appear to motivate achievement through behavior consistent with the ideal and distinct from the feared possible selves.

Further distinctions in self-concept, called "differentiation," occur as the adolescent recognizes the contextual influences on their own behavior and the perceptions of others, and begin to qualify their traits when asked to describe themselves. Differentiation appears to be fully developed by mid-adolescence. Peaking in the 7th-9th grades, the personality traits adolescents use to describe themselves refer to specific contexts, and therefore may contradict one another. The recognition of inconsistent content in the self-concept is a common source of distress in these years (see Cognitive dissonance), but this distress may benefit adolescents by encouraging structural development.

Differentiation results in organization and integration of the self-concept. The multifaceted self is understood to include several stable, if inconsistent, sets of traits applicable when the individual with different people and circumstances. This includes negative traits and weaknesses, which adolescents can now recognize and qualify: "consistent with this, adolescents who have more complex self-conceptions are less likely to be depressed." Moreover, although only true in some circumstances, differentiated traits are contrasted with "false-self behavior," which is not representative of the "real" self. Recognition of the inauthentic indicates that the adolescent is gaining a sense of continuous, overlapping, coherent sense of identity.

Sense of identity

Unlike the conflicting aspects of self-concept, identity represents a coherent sense of self stable across circumstances and including past experiences and future goals. Everyone has a self-concept, whereas Erik Erikson argued that not everyone fully achieves identity. Erikson’s theory of stages of development includes the identity crisis in which adolescents must explore different possibilities and integrate different parts of themselves before committing to their beliefs. He described the resolution of this process as a stage of "identity achievement" (see Fig. 1) but also stressed that the identity challenge "is never fully resolved once and for all at one point in time." Adolescents begin by defining themselves based on their crowd membership. "Clothes help teens explore new identities, separate from parents, and bond with peers". Fashion has played a major role when it comes to a teenager "finding their selves"; Fashion is always evolving, which corresponds with the evolution of change in the personality of teenagers. Just as fashion is evolving to influence adolescents so is the media. "Modern life takes place amidst a never-ending barrage of flesh on screens, pages, and billboards." This barrage consciously or subconsciously registers into the mind causing issues with self-image a factor that contributes to an adolescence sense of identity. Researcher James Marcia developed the current method for testing an individual’s progress along these stages. His questions are divided into three categories: occupation, ideology, and interpersonal relationships. Answers are scored based on extent to which the individual has explored and the degree to which he has made commitments. The result is classification of the individual into a) Identity Diffusion in which all children begin, b) Identity Foreclosure in which commitments are made without the exploration of alternatives, c) Moratorium, or the process of exploration, or d) Identity Achievement in which Moratorium has occurred and resulted in commitments.

Research since reveals self-examination beginning early in adolescence, but identity achievement rarely occurring before age 18. The freshman year of college influences identity development significantly, but may actually prolong psychosocial moratorium by encouraging reexamination of previous commitments and further exploration of alternate possibilities without encouraging resolution. For the most part, evidence has supported Erikson’s stages: each correlates with the personality traits he originally predicted. Studies also confirm the impermanence of the stages there is no final endpoint in Identity Development.

Self-esteem

The final major aspect of identity formation is self-esteem, one’s thoughts and feelings about one’s self-concept and identity. Contrary to popular belief, there is no empirical evidence for a significant drop in self-esteem over the course of adolescence. ‘Barometric self-esteem’ fluctuates rapidly and can cause severe distress and anxiety, but baseline self-esteem remains highly stable across adolescence. The validity of global self-esteem scales has been questioned, and many suggest that more specific scales might reveal more about the adolescent experience. For girls, they are most likely to enjoy high self-esteem when engaged in supportive relationships with friends, the most important function of friendship to them is having someone who can provide social and moral support. When they fail to win friends' approval or couldn't find someone with whom to share common activities and common interests, in these cases, girls will suffer from low self-esteem. In contrast, boys are more concerned with establishing and asserting their independence and defining their relation to authority. As such, they are more likely to derive high self-esteem from their ability to successfully influence their friends; on the other hand, the lack of romantic competence, for example, failure to win or maintain the affection of the opposite or same-sex (depending on sexual orientation), is the major contributor to low self-esteem in adolescent boys.

Relationships

Family

See also: Sibling relationship

Adolescence marks a rapid change in one’s role within a family. Young children tend to assert themselves forcefully, but are unable to demonstrate much influence over family decisions until early adolescence, when they are increasingly viewed by parents as equals. When children go through puberty, there is often a significant increase in parent-child conflict and a less cohesive familial bond. Arguments often concern minor issues of control, such as curfew, acceptable clothing, and the adolescent's right to privacy, which adolescents may have previously viewed as issues over which their parents had complete authority. Parent-adolescent disagreement also increases as friends demonstrate a greater impact on one another, new influences on the adolescent that may be in opposition to parents’ values. Although conflicts between children and parents increase during adolescent, these are just relatively minor issues. Regarding to the important issues in lives, most adolescent still share the same attitudes and values as their parents.

During childhood, siblings are a source of conflict and frustration as well as a support system. Adolescence may affect this relationship differently, depending on sibling gender. In same-sex sibling pairs, intimacy peaks during early adolescence, then steadily declines. Mixed-sex siblings pairs act in the opposite way; siblings drift apart during early adolescent years, but experience an increase in intimacy starting at middle adolescence. Sibling interactions are children's first relational experiences, the ones that shape their social and self-understanding for life. Sustaining positive sibling relations can assist adolescents in a number of ways. Siblings are able to act as peers, and may increase one another's sociability and feelings of self-worth. Older siblings can give guidance to younger siblings, although the impact of this can be either positive or negative depending on the activity of the older sibling.

Despite changing family roles during adolescence, the home environment and parents are still important for the behaviors and choices of adolescents. Adolescents who have a good relationship with their parents are less likely to engage in various risk behaviors, such as smoking, drinking, fighting, and/or unprotected sexual intercourse. In addition, parents influence the education of adolescence. A study conducted by Adalbjarnardottir and Blondal (2009) showed that adolescence at the age of 14 who identifies their parents as authoritative figures, are more likely to complete their secondary education by the age of 22 as the support and encouragement from an authoritative parent motivates the adolescence to complete their schooling, in order to avoid disappointing the parent.

Peers

Peer groups are especially important during adolescence, a period of development characterized by a dramatic increase in time spent with peers and a decrease in adult supervision. Adolescents also associate with friends of the opposite sex much more than in childhood and tend to identify with larger groups of peers based on shared characteristics.

Peer groups offer members the opportunity to develop various social skills, such as empathy, sharing and leadership. Peer groups can have positive influences on an individual, for instance on academic motivation and performance, but they can also have negative influences and lead to an increase in experimentation with drugs, drinking, vandalism, and stealing. Susceptibility to peer pressure increases during early adolescence, peaks around age 14, and declines thereafter.

During early adolescence, adolescents often associate in cliques, exclusive, single-sex groups of peers with whom they are particularly close. Towards late adolescence, cliques often merge into mixed-sex groups as teenagers begin romantically engaging with one another. Typically, in schools, the most popular boys would participate in achievement-oriented activities, which were highly competitive and aggressive such as, athletics. Likewise, the most popular girls would participate in the most interesting social activities, ranging from skiing to late-night parties. Of course, girls who engaged in these activities had to be physically attractive to compete for the opposite sex's attention. Thus, it became common to attribute competitiveness to boys and attractiveness with girls in clique groups. These small friend groups break down even further as socialization becomes more couple-oriented. Despite the common notion that cliques are an inherently negative influence, they may help adolescents become socially acclimated and form a stronger sense of identity. Cliques also have become somewhat as a "collective parent." This means they are being the people who tell them what to do and what not to do. Peter Greir in The Christian Science Monitor states, "Call it the benign side of peer pressure. Today's high-schoolers operate in groups that play the role of nag and nanny--in ways that are both beneficial and isolating."

On a larger scale, adolescents often associate with crowds, groups of individuals who share a common interest or activity. Often, crowd identities may be the basis for stereotyping young people, categorizing them as jocks, nerds, and so on. In large, multi-ethnic high schools, there are often ethnically-determined crowds as well. While crowds are very influential during early and middle adolescence, they lose salience during high school as students identify more individually.

While peers may facilitate social development for one another, they may also hinder it. Both physical and relational aggression are linked to a vast number of enduring psychological difficulties, especially depression, as is social rejection. Because of this, bullied adolescents often develop problems that lead to further victimization.

Romance and sexual activity

Main article: Adolescent sexuality

See also: Adolescent sexuality in the United States

Romantic relationships tend to increase in prevalence throughout adolescence. By age 15, 53% of adolescents have had a romantic relationship that lasted at least one month over the course of the previous 18 months. In a 2008 study conducted by YouGov for Channel 4, 20% of 14−17-year-olds surveyed revealed that they had their first sexual experience at 13 or under in the United Kingdom. A 2002 American study found that those aged 15–44 reported that the average age of first sexual intercourse was 17.0 for males and 17.3 for females. The typical duration of relationships increases throughout the teenage years as well. This constant increase in the likelihood of a long-term relationship can be explained by sexual maturation and the development of cognitive skills necessary to maintain a romantic bond (e.g. caregiving, appropriate attachment), although these skills are not strongly developed until late adolescence. Long-term relationships allow adolescents to gain the skills necessary for high-quality relationships later in life and develop feelings of self-worth. Overall, positive romantic relationships among adolescents can result in long-term benefits. High-quality romantic relationships are associated with higher commitment in early adulthood and are positively associated with self-esteem, self-confidence, and social competence.

Adolescence marks a time of sexual maturation, which manifests in social interactions as well. While adolescents may engage in casual sexual encounters (often referred to as hookups), most sexual experience during this period of development takes place within romantic relationships. Kissing, hand holding, and hugging signify satisfaction and commitment. Among young adolescents, "heavy" sexual activity, marked by genital stimulation, is often associated with violence, depression, and poor relationship quality. This effect does not hold true for sexual activity in late adolescence that takes place within a romantic relationship.

Teenage couples at a fair in the American West.

The age of consent to sexual activity varies widely among international jurisdictions, ranging from 12 to 20 years. Adolescents often date within their demographic in regards to race, ethnicity, popularity, and physical attractiveness. However, there are traits in which certain individuals, particularly adolescent girls, seek diversity. While most adolescents date people approximately their own age, boys typically date partners the same age or younger; girls typically date partners the same age or older.

Some researchers are now focusing on learning about how adolescents view their own relationships and sexuality; they want to move away from a research point of view that focuses on the problems associated with adolescent sexuality. Lucia O’Sullivan and her colleagues found that there weren’t any significant gender differences in the relationship events adolescent boys and girls from grades 7-12 reported. Most teens said they had kissed their partners, held hands with them, thought of themselves as being a couple and told people they were in a relationship. This means that private thoughts about the relationship as well as public recognition of the relationship were both important to the adolescents in the sample. Sexual events (such as sexual touching, sexual intercourse) were less common than romantic events (holding hands) and social events (being with one’s partner in a group setting). The researchers state that these results mean that researchers should focus more on the positive aspects of adolescents and their social and romantic interactions rather than put most of their focus on sexual behavior and its consequences.

Dating violence is fairly prevalent within adolescent relationships. When surveyed, 10-45% of adolescents reported having experiencing physical violence in the context of a relationship while one-third to a quarter of adolescents reported having experiencing psychological aggression. This reported aggression includes hitting, throwing things, or slaps, although most of this physical aggression does not result in a medical visit. Physical aggression in relationships tends to decline from high school through college and young adulthood. By their early twenties, many fewer romantic couple engage in physical aggression, and aggressors tend to be much more deviant. In heterosexual couples, there is no significant difference between the rates of male and female aggressors, a surprising finding considering the common assumption that males are more aggressive overall. Despite these jarring statistics, nurturant parenting style is associated with lower rates of relationship violence.

In contemporary society, adolescents also face some risks as their sexuality begins to transform. Whilst some of these such as emotional distress (fear of abuse or exploitation) and sexually transmitted diseases (including HIV/AIDS) are not necessarily inherent to adolescence, others such as pregnancy (through non-use or failure of contraceptives) are seen as social problems in most western societies. One in four sexually active teens will contract a sexually transmitted disease, or STD, according to the Alan Guttmacher Institute.

"What nearly everyone agrees on is that STDs and risky "anything but intercourse" behaviors are rampant among teens—and that what to do about it is a very complicated question. Across the country, clinicians report rising diagnoses of herpes and human papillomavirus, or HPV (which can cause genital warts), which are now thought to affect 15 percent of the teen population. Girls 15 to 19 have higher rates of gonorrhea than any other age group. One quarter of all new HIV cases occur in those under the age of 21. "It's a serious epidemic," says Lloyd Kolbe, director of the CDC's Adolescent and School Health program. "We're worried."' Multrine also states in her article that according to a March survey by the Kaiser Family Foundation, eighty-one percent of parents want schools to discuss the use of condoms and contraception with their children. They also believe students should be able to be tested for STD's since children will obviously do whatever they please. This would in turn create a solution for not having unwanted sexual advances. Furthermore, teachers want to address such topics with their students. But, although 9 in 10 sex education instructors across the country believe that students should be taught about contraceptives in school, over one quarter report receiving explicit instructions from school boards and administrators.

In terms of sexual identity, while all sexual orientations found in adults are also represented among adolescents, statistically the suicide rate amongst LGBT adolescents is up to four times higher than that of their heterosexual peers.

For more complete information on how socialization and gender affect adolescent sexuality, please visit the main article: Adolescent sexuality.

According to anthropologist Margaret Mead, the turmoil found in adolescence in Western society has a cultural rather than a physical cause; they reported that societies where young women engaged in free sexual activity had no such adolescent turmoil.

Culture

In commerce, this generation (21st century adolescence) is seen as an important target. Mobile phones, electronic devices, contemporary popular music, movies, television programs, websites, sports, video games and clothes are heavily marketed and often popular amongst adolescents. There are also many different ways of viewing adolescence that are prevalent in the world today.

Sexuality

There are many cultural and socio-economic differences which influence how adolescents' sexuality develops. Menarche (the first menstrual period of a female-bodied person’s life) is, for many cultures, the defining point for the beginning of a transition into adulthood. The age of menarche varies from culture to culture. Girls from countries where menarche/menstruation is seen as an important event, or where there is an ambivalence towards it, tend to have more negative opinions about it. An adolescent’s sexual socialization is highly dependent upon the society they live in, and how restrictive or permissive that society is when it comes to sexual activity.

Restrictive societies "pressure youngsters to refrain from sexual activity until they either have undergone a formal rite of passage or have married." Therefore the sexual transition of adolescence is highly discontinuous because there is little preparation for an adult sexuality. These cultures either control adolescence by separating the males and females throughout their development, or they restrict sexual activity through public shaming and physical punishment.

In semi-restrictive societies, adults do not condone sexual activity however often do not take strong steps towards restricting it. "Premarital promiscuity is common, and the parents do not object as long as the love affairs are kept secret." While some media portrays the United States as a permissive society, adults frequently try to discourage sexual activity among adolescence. This is most obvious among adolescence women because it is premarital pregnancy, rather than premarital sex that is highly objectionable in the United States. It is also common for adults to lecture women about sex and the importance of virginity by telling them that females do not need sex as much as males do. Despite these attempts to reduce sexual promiscuity, parents in the United States and other semi-restrictive societies do not prohibit young men and women from interacting both in social and private settings. The Ledger Survey discovers that 55 percent of teenage males and 58 percent of females do not feel comfortable discussing the subject of sex with their parents.

In permissive societies, the transition into sexual adulthood is highly continuous and begins at an early age. Some examples of sexually permissive societies are the Pukapukans of Polynesia and Trobiand girls and boys. In the Pukapukans society, parent simply ignore any sexual activity among children even when they are masturbating freely and openly in public. In the Trobiand society, young girls and boys participate in oral stimulation as a means of amusement and are encourage to participate in sexual activity with other young girls and boys at any time, they are encouraged to go into any hut or hide behind any bush.

Autonomy

Another way to define the development of adolescents is their strive for autonomy. According to McElhaney et al., there are three ways in which autonomy can be described. The first being emotional autonomy which is stated as being the development of more adult-like close relationship with adults and peers. The second form of autonomy is behavioral autonomy, which is the ability to be able to make independent decisions and follow through with them. The third is known as cognitive autonomy and is characterized as the manifestation of an independent set of beliefs, values and opinions. Most of the cultural differences however tend to be visible in behavioral autonomy as this is based on when adolescence are allowed to go on dates, or go out with friends.

One way in which the cultural differences in behavioral autonomy is by comparing the "teen timetables" of parents and adolescents of different cultures. The "teen timetable" is "a questionnaire that asks at what age adolescents should be permitted to engage in various behaviors that signal autonomy." When comparing the timetables of White and Asian families across the world, it can be concluded that in general, White parents and adolescents tend to expect autonomy earlier than their Asian counterparts, disregarding whether the families lived in America, Australia, or Hong Kong. It is also the case that an adolescents mental health is best when their feelings of autonomy match closely with their parents. It is for this reason, recent emigrants, that move from a culture that normally grants autonomy at a later age to a culture with a younger age at which autonomy is granted, often experience family stress. Since adolescence generally become accustomed to the novel culture quicker than adults, the learn to expect autonomy earlier than their parents.

Time use and work

American teenagers spend more time on leisure than many other countries. The average American adolescent spends about five hours a week on homework, while Indian, Taiwanese, and Japanese students spend an average of five hours a day. This is most likely due to the amount of emphasis and pressure that is placed on adolescents’ education in those countries. Americans tend to spend more time playing sports, socializing, caring for their appearance, and working after-school jobs. Differences in how American teens use their leisure time tend to be influenced by their amount of involvement in various activities rather than ethnicity or socioeconomic background. Busier, more well-rounded teens tend to be better-adjusted and more goal-oriented than their peers who engage in only one activity (such as sports) or none.

In many developing countries, it is common for adolescents to drop out of high school and start working. These adolescents generally receive full-time positions by the age of 15-16 and they often stay in the same jobs for the remainder of their lifetime. It is the case though that the rate of adolescents in the workforce today is decreasing. One example of this is China, where as the accessibility of education has increased, the amount of adolescents in the workforce has dropped drastically. Half of all 16-year-olds were employed in 1980 however in 1990, only fewer than one quarter were in workforce. When comparing more industrialized countries, American adolescents are far more likely to hold jobs than both Asian and European countries. Two thirds of American high school juniors hold jobs during the school year where as only one quarter of Taiwanese and Japanese juniors do. In many European countries such as France, Hungary and Switzerland adolescents do not work at all and if they do hold jobs, then they are informal, only last for a few hours a week, and more most commonly jobs such as babysitting.

Legal issues, rights and privileges

Internationally, those who reach a certain age (often 18, though this varies) are legally considered to have reached the age of majority and are regarded as adults and are held to be responsible for their actions. People below this age are considered minors or children. A person below the age of majority may gain adult rights through legal emancipation. Despite the legal adult age of 18, many specific rights such as consumption, voting, consent, and working have different ages around the world.

A sign outside a sex shop reads "Must Be 18 To Enter" in Chapel Hill, North Carolina.

The legal working age in Western countries is usually 14 to 16, depending on the number of hours and type of employment. In the United Kingdom and Canada, for example, young people between 14 and 16 can work at certain types of light work with some restrictions to allow for schooling; while youths over 16 can work full-time (excluding night work). Many countries also specify a minimum school leaving age, ranging from 10 to 18, at which a person is legally allowed to leave compulsory education.

In most democratic countries, a citizen is eligible to vote at 18. For example, in the United States, the Twenty-sixth amendment decreased the voting age from 21 to 18. In a minority of countries, the voting age is 17 (for example, Indonesia) or 16 (for example, Brazil). By contrast, some countries have a minimum voting age of 21 (for example, Singapore) whereas the minimum age in Uzbekistan is 25. Age of candidacy is the minimum age at which a person can legally qualify to hold certain elected government offices. In most countries, a person must be 18 or over to stand for elected office, but some countries such as the United States and Italy have further restrictions depending on the type of office.

The sale of selected items such as cigarettes, alcohol, and videos with violent or pornographic content is also restricted by age in most countries. In the U.S, the minimum age to buy an R-rated movie, M-rated game or an album with a parental advisory label is 17 (although this is normally by custom and not by law- in some states, the age is 18 or even 21). In the United States, teenagers are allowed to drive between 14–18 (each state sets its own minimum driving age of which a curfew may be imposed), in the US, adolescents 17 years of age can serve in the military. In Europe it is more common for the driving age to be higher (usually 18) while the drinking age is lower than that of the US (usually 16 or 18). In Canada, the drinking age is 18 in some areas and 19 in other areas. In Australia, universally, the minimum drinking age is 18, unless a person is in a private residence or is under parental supervision in a licensed premises. The driving age varies from state to state but the more common system is a graduated system of "L plates" (a learning license that requires supervision from a licensed driver) from age 16, red "P plates" (probationary license) at 17, green "P plates" at 18 and finally a full license, i.e. for most people around the age of 20. The legal gambling age also depends on the jurisdiction, although it is typically 18.

The age of consent to sexual activity varies widely between jurisdictions, ranging from 13 to 20 years. The age at which people are allowed to marry also varies, with ages as low as 13 and as high as 22 both existing. In Western countries, people are typically allowed to marry at 18, although they are sometimes allowed to marry at a younger age with parental or court consent.

Since the advent of the Convention on the Rights of the Child in 1989 (children defined as under 18), almost every country (except the U.S. & Somalia) in the world has become voluntarily legally committed to advancing an anti-discriminatory stance towards young people of all ages. This is a legally binding document which secures youth participation throughout society while acting against unchecked child labor, child soldiers, child prostitution, and pornography.

Transitions into adulthood

A broad way of defining adolescence is the transition from child-to-adulthood which happens to vary drastically in time between cultures. In some countries, such as the United States, adolescence can last nearly a decade, but in others, the transition—often in the form of a ceremony—can last for only a few days.

In the U.S., while there are no marked ceremonies, there are popular social and religious traditions that tend to mark this transition, such as Confirmation, Bar Mitzvahs, Bat Mitzvahs, Quinceañeras, Sweet Sixteens, cotillions, and débutante balls. In other countries, initiation ceremonies play an important role, marking the transition into adulthood or the entrance into adolescence. The transition is usually accompanied by obvious physical changes, which can vary from a change in clothing to tattoos and scarification.

Female specific rituals

One example of a female-bodied ritual is the first menstruation ritual in Sri Lanka. This ritual consists of isolating the female immediately after her first menstruation of the "killa", which is believed to be evil, and keeping her in isolation for the next three days. On the fourth day, a ritual bath is given by the mother or a washing woman ("redi nändà"), who is paid to take away the clothes soaked in "killa" and rid the house of "vas", the evil eye.

Another example of a rite of passage are the Dipo rituals which are performed by the Krobo in Ghana. This rite of passage consists of two separate rituals, one private and one public. The private ritual lasts around threesacred stone, which determines their virginity and, thus, their suitability to perpetuate the proud tradition of Krobo womanhood." After this encounter, the women partake in a five day outdoor ceremony where they dance for the men of the tribe and potential husbands.

Male specific rituals

One example of a male specific coming of age ritual can be seen amongst the Maasai people. They have many different ceremonies that are based about the learning of brotherhood and how to be a true warrior or husband but the most important ceremony is the "Emuratare". The "Emuratare" is the circumcision ceremony that is required for Maasai boys to become warriors. It is done when the boy is between the ages of 14-16. Before the ceremony, they are required to herd cattle for seven days in order to prove they are worthy of being called a warrior. On the eighth day, the weeks and its goal is to teach "the finer points of personal grooming, female conduct, domesticity, and, finally, the arts of dance and seduction. After their training, the man must pass a final test which consists of a "ritual encounter with Tekpete, the boy is publicly circumcised. During the process, he is not allowed to show any signs of pain. If he does, he will be considered weak. These rituals are mainly directed towards boys, as the Maasai women focus on marriage as a coming of age ritual.

Media

Stereotypes

The mass media greatly exaggerates adolescent problem behaviors. Media portrayals of drug use, sexual encounters, and psychological and behavioral disorders are rarely accurate. For example, though television often portrays scenarios such as these, a romantic breakup does not necessarily lead to heavy depression or suicide, and one drink at a party does not often end in a lifetime of addiction or a fatal car crash. Because people view these negative stereotypes about adolescents so often in the media, they are led to believe that adolescence is always a very problematic time of development. Adolescence is a period of development in which it is very normal to seek independence, explore personal identities, and pursue relationships, and thus it is expected that some of the experimentation that adolescents engage in is risky. It is extremely important to distinguish between occasional experimentation during adolescence and long-term problem behaviors. For example, although many teenagers will commit an act that is against the law during their adolescent years, relatively few adolescents continue on to commit criminal acts in their later lives. Further, it is very important to distinguish between problems that first occur during adolescence and those that may have developed during childhood. The majority of adolescents who have continuous problems with the law during adolescence also had problems at an early age, even as early as preschool. Thus, even if a problem is displayed during adolescence, it may not be a problem related to adolescence. What’s more, what the media neglects to mention is that most problems that adolescents experience are resolved by the time they reach adulthood. For example, delinquency, drug use, and eating disorders are all experienced more by the adolescent population than the adult population. The adolescents that take part in these behaviors often abandon them as they reach the beginning of adulthood. Oftentimes, the adults that do continue with these behaviors from adolescence often had problematic childhoods, which in turn led to problematic adolescent and adult years. Thus, though the media often proclaims that the problem behaviors of adolescents are causing the downfall of civilization, it is important to remember that most of these behaviors fade over time. Finally, delinquent or problem behaviors that occur during adolescence are hardly ever a direct result of adolescence. For example, media theories that blame problem behaviors, rebellions, and identity crises of adolescents on their hormones actually have no scientific support. In fact, hormonal changes during adolescence only have a very small impact on adolescent behavior. Thus, contrary to the suggestions of the popular media, when an adolescent experiences a very serious psychological problem, this behavior is usually not normative and is most likely a sign that something is not right.

Media profusion

Because access to media has increased so quickly through a vast number of mediums such as computers, cell phones, stereos and televisions, adolescents’ use of media has skyrocketed in the past decade. Almost all American households have at least one television, more than three quarters of all adolescents’ homes have access to Internet, and more than 90% of American adolescents use the Internet at least occasionally. As a result of the amount of time adolescents spend using these devices, their total media exposure is extremely high - the average adolescent uses one of the mass media more than 6 hours a day. What’s more, when multitasking with more than one media device is taken into account, every day, adolescents are exposed to media for between 8 and 9 hours. In the last decade, the amount of time that adolescents spend on the computer has greatly increased. Online activities with the highest rates of use among adolescents are video games (78% of adolescents), email (73%), instant messaging (68%), social networking sites (65%), news sources (63%), music (59%), and videos (57%). In fact, because adolescents spend so much time playing video games, some research has suggested that 10% of preadolescents and adolescents are "pathological". However, better academic performance has been associated with moderate Internet use.

Theories on media impact

There is much debate over the impact that media has on adolescents’ development and behavior. However, because adolescents choose which media they’re exposed to, it is very difficult for researchers to distinguish cause and effect. For example, though one could argue that violent video games and films may spur aggression, it is just as likely that aggressive adolescents are more likely to choose to watch these violent images. There are three widely known theories regarding the impact of media on adolescent development and behavior. The first, referred to as the cultivation theory, argues that adolescents’ beliefs are very much shaped by the media. An example of cultivation theory would be believing that if adolescents watch beer commercials during the Super Bowl, they would then be influenced to drink beer. The second theory, the uses and gratifications theory, suggests that adolescents choose which media they are exposed to. According to this theory, adolescents choose media that is consistent with their interests, and thus adolescents who drink beer are more likely to watch football and be exposed to and influenced by beer commercials. The last theory regarding media influence is the media practice model. This model revolves around the idea that adolescents’ preferences and their media exposure are reciprocal, and that adolescents choose what media they’re exposed to, as well as interpret the media in ways that influence how much impact it has on them.

Exposure to controversial media content

Most research has focused on the impact of television on development. Because of this, little is known about the effects of other media on adolescent development. The topics most focused on by researchers are drugs, violence, and sex, though researchers disagree about the magnitude of the effects of adolescents' exposure to these concepts in the media. However, most scholars agree that adolescents are regularly exposed to controversial media content.

Of the television shows popular among adolescents, more than 70% display sexual content and images, and there are approximately seven sexual scenes per hour of television. However, with the increases in reality television shows, sexual content has declined since 2000. Usually, sex portrayed in television shows and music videos is casual and untroubled, with humorous or suggestive undertones. In the past, some scholars have expressed concern that sexual messages in the media are unrealistic, particularly with regard to women. Furthermore, the media often portrays men as aggressive and dominant, while women are often portrayed as more submissive. Comparatively, there is a lack of messages regarding the consequences of sex, physically and mentally.

Violent imagery is often depicted in film, music, and video games, commonly used by adolescents. Because more than 60% of television shows contain violence, adolescents view approximately 10,000 media violence acts every year. According to some research, adolescents who play relatively more violent video games are involved in more fights and get into more arguments than peers who play fewer such games. Furthermore, some studies suggest that violent lyrics to songs increase the aggressive thoughts of individuals who listen to them. However, it is highly debated whether these violent games or lyrics actually cause adolescents to commit acts of real-life aggression, especially because violence among adolescents has declined in the past decade even though the sale of violent video games has increased. The most recent research suggests that there is little correlation between consuming violence in the media and actual aggressive acts among youth.

In the mass media, alcohol, tobacco, and illicit drugs use are commonly depicted. During the 1990s these three substances were displayed in about 70% of television shows, many movies, and around 25% of music videos. Approximately 10% of all television commercials were for alcoholic beverages during that time. Also, advertisements for liquor and tobacco had been becoming ever-present on the Internet, with their companies sponsoring websites and chat rooms. By contrast, however, more research by the Parents Television Council, suggests that prevalence of smoking on television is currently rare. Research has found that adolescents are more likely to smoke if their favorite film star is a smoker. Some research suggests that adolescents who are less likely to smoke are more likely to be affected by seeing smoking in movies. Because of this, anti-smoking ads are now often on the DVDs of films that contain smoking. However, these findings are correlational, not causal, and other research has found that peers, not media, influence teen smoking. However, anti-drinking and anti-smoking ads have been shown to be effective in changing the beliefs and attitudes of adolescents about drinking and smoking.

Electronic media influence

Because it is becoming increasingly easier to communicate via electronic communication, the way adolescents socialize has changed. The effects of adolescents’ online socialization are very controversial and intriguing. Many are concerned over whether electronic communication versus in-person communication negatively affects the development of adolescents, and there are also worries over whether strangers who intend to harm adolescents, like sexual predators, are easily able to contact and develop relationships with adolescents through publicly posted information on social websites.

Research

In a survey, conducted by Teenage Research Unlimited: 30%--Percentage of who teens have been text messaged 10, 20, or 30 times an hour by a partner wanting to know where they are, what they're doing, or who they're with. 25%--Percentage of who teens in a relationship have been called names, harassed, or put down by their partner through cellphones and texting. 22%--Percentage of teens in a relationship who have been asked via cellphone or online message to engage in a sexual activity when they did not want to. 10%--Percentage of teens who have been threatened physically via e-mail, IM, text messaging, chat rooms, etc.

Internet impact

Many adolescents' parents worry that electronic communication may negatively affect their social development, replace face-to-face communication, negatively affect their social skills, lead to unsafe communication with strangers, and replace more valuable activities. Though research is inconclusive, it suggests that the effects of Internet use are very small. However, Internet may have a negative effect on the physical health of adolescents, as time spent using the Internet replaces time doing physical activities. For example, a typical 15 year old American adolescent spends approximately 6 hours a day sitting in front of screens, but less than 1 hour doing physical activity. However, the Internet can be extremely useful in educating teens about accurate health information, though the usefulness depends on the quality and content of the websites’ material. Studies have found that it depends on what teens are doing online that determines whether high Internet use is harmful to their development. Research suggests that Internet communication brings friends closer and is beneficial for socially anxious teens, who find it easier to interact socially online. Alternatively, getting to know strangers online and developing friendships with them may lower the quality of relationships with one’s friends. Though many parents worry about their adolescents becoming addicted to their computers, Internet use addiction rates among adolescents are extremely low, as is electronic bullying (or cyber bullying) though the popular media often suggests otherwise.

Every year, approximately 13% of adolescents are sexually solicited online, and about 4% of the solicitations are also followed with solicitation for contact not through a computer medium. Most of the adolescents at risk for solicitation are females of high school age and boys who identify themselves as gay. Studies show that posting personal information on social networking sites such as MySpace or Facebook does not pose risks for sexual solicitation - instead, it is the way that adolescents interact with others online that places them at risk for unwanted sexual solicitation. Also, though parents often are concerned about adolescents viewing pornography on the Internet, most pornography that adolescents view is unwanted and unsought. In fact, most teens spend their time on the Internet visiting entertainment websites and websites that are most frequented by adults rather than visiting pornographic websites.

The impact of Internet use on cognitive development has not been widely studied. However, there isn’t any evidence that Internet use benefits or has any negative effects on the school performance of adolescents. What’s more, there are a few studies that have shown that playing video games may improve reaction times, hand-eye coordination, and improve visual skills.

Effect on adolescent girl body image

Because of concerns over body dissatisfaction among teenage girls, research has been conducted on the effects of the messages aimed toward adolescent females in the mass media. Many magazine advertisements emphasize the necessity of physical attractiveness and advocate thinness. Some research has shown that adolescent females who read fashion magazines on a regular basis are more dissatisfied with their bodies than their peers who do not read the magazines as often or at all. However, most meta-analyses of this research find effect sizes for the relationship between media and body dissatisfaction to be small or negligible. Effect sizes from meta-analysis generally range from correlational coefficient r = .08 to r = .17, and note inconsistencies between studies. Other research suggests that adolescent girls who read magazines featuring articles and advertisements about dieting and weight loss partake in more unhealthy behaviors for weight control, such as taking laxatives and vomiting to lose or maintain weight. However, other scholars have contested this view, noting that the research is inconsistent and effects are generally small and inconsistent across studies.

Consumption

Adolescents are a very attractive target for many businesses because of their population size, their lack of savings habits, and the prevalence of their employment. An average Western adolescent spends nearly all of their approximately $400 in spending money per month. This money is often spent on leisure activities such as food, clothes, cosmetics, cars, and stereo equipment. Though some believe that advertising aimed at adolescents takes advantage of their impulsiveness and self-consciousness, proponents of adolescent consumerism argue that it is not only advertising, but the strong influences that teens have on each other regarding their purchases that drives adolescent consumerism. This peer influence has become known as viral marketing, in which products are promoted by encouraging individuals to pass information on to others. The adolescent market also extends into the adult market (often because of teens’ influences on their parents’ purchases), with adult clothing and music often exhibiting the same trends as adolescents’, only toned-down.

See also

• Adolescent medicine
• Children and adolescents in the United States
• Clique
• Ephebophilia - a sexual preference in which an adult is primarily or exclusively sexually attracted to mid to late adolescents
• Fear of youth
• Images of young people
• Juvenile delinquency
• Medical School
• Parental abuse by adolescents
• Parental abuse of adolescents
• Pedophilia (or paedophilia) - a psychiatric disorder in adults or late adolescents over 15 for whom prepubescent children are the primary or exclusive sexual object of their libido.
• Relational aggression
• Rite of passage
• Sex education
• Student voice
• Suitable age and discretion
• Teen Dating Violence
• Teen drama - (List of teen dramas)
• Teen film - (List of teen films)
• Teen idol
• Teen magazine
• Teen pop
• Timeline of children's rights in the United Kingdom
• Timeline of children's rights in the United States
• Young adult
• Youth
• Youth culture
• Youth voice
• Young worker safety and health

Further reading

• Tennessee Williams - a description of the emotional impact of puberty and adolescence is to be found in The Resemblance Between a Violin and a Coffin
• Jon Savage - a (pre)history of the development of the teenager is to be found in Teenage (Chatto and Windus, 2007)

References

Preceded by Preadolescence

Stages of human development Adolescence

Succeeded by Young adult

UpToDate Contents

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• 1. 思春期の予防サービスに関するガイドライン guidelines for adolescent preventive services
• 2. 思春期の性 adolescent sexuality
• 3. 避妊：思春期に固有の問題の概要 contraception overview of issues specific to adolescents
• 4. 性感染症：思春期特有の問題の概要 sexually transmitted diseases overview of issues specific to adolescents
• 5. 思春期における多嚢胞性卵巣症候群の診断的評価 diagnostic evaluation of polycystic ovary syndrome in adolescents

English Journal

• Normative data and percentile curves of bone mineral density in healthy Iranian children aged 9-18 years.

• Jeddi M, Roosta MJ, Dabbaghmanesh MH, Omrani GR, Ayatollahi SM, Bagheri Z, Showraki AR, Bakhshayeshkaram M.SourceEndocrine and Metabolism Research Center, Nemazee Hospital, Shiraz University of Medical Sciences, Shiraz, Iran.
• Archives of osteoporosis.Arch Osteoporos.2013 Dec;8(1-2):114. doi: 10.1007/s11657-012-0114-z. Epub 2013 Jan 8.
• We provide the first reference values for bone mineral content and bone mineral density according to age and sex in Iranian children and adolescents. The prevalence of hypovitaminosis D was high, and levels of physical activity were low in our sample. Multiple regression analyses showed age, BMI, an
• PMID 23297104

• Epidemiology of primary brain tumors in childhood and adolescence in Kuwait.

• Katchy KC, Alexander S, Al-Nashmi NM, Al-Ramadan A.SourceDepartment of Pathology, Al-Sabah Hospital, Safat, Kuwait ; FRCPath, FRCPC, Department of Pathology, Al-Sabah Hospital, P.O.Box 4078, 13041 Safat, Kuwait.
• SpringerPlus.Springerplus.2013 Dec;2(1):58. Epub 2013 Feb 18.
• The relatively high frequency of primary brain tumors (PBT) observed in childhood and adolescence in Kuwait has necessitated this epidemiological study. It is based on the records of the Department of Pathology, Al-Sabah Hospital, which examined all brain tumor biopsies done in this age group in Kuw
• PMID 23519270

• Alcohol exposure during development: Impact on the epigenome.

• Perkins A, Lehmann C, Lawrence RC, Kelly SJ.SourceDepartment of Psychology, University of South Carolina, Columbia, SC, 29208, United States. Electronic address: fincha@sc.edu.
• International journal of developmental neuroscience : the official journal of the International Society for Developmental Neuroscience.Int J Dev Neurosci.2013 Oct;31(6):391-7. doi: 10.1016/j.ijdevneu.2013.03.010. Epub 2013 Mar 27.
• Fetal alcohol spectrum disorders represent a wide range of symptoms associated with in utero alcohol exposure. Animal models of FASD have been useful in determining the specific neurological consequences of developmental alcohol exposure, but the mechanisms of those consequences are unclear. Long-la
• PMID 23542005

Japanese Journal

• 思春期デイケアを活用した不登校・ひきこもりケースの支援 (特集 不登校・ひきこもりに対する精神科医療の関わり)

• 朝倉 新
• 精神科治療学 34(4), 397-402, 2019-04
• NAID 40021894815

• 五稜会病院ストレスケア・思春期病棟におけるアメニティ : 患者満足度を高めるための工夫 (特集 患者さん想いの病院アメニティ)

• 中島 公博
• 日本精神科病院協会雑誌 = Journal of Japanese Association of Psychiatric Hospitals 38(4), 295-300, 2019-04
• NAID 40021890761

• 学校教員を対象としたメンタルヘルスリテラシー教育プログラムの効果検証 : パイロットスタディ

• 山口 智史,西田 明日香,小川 佐代子,小塩 靖崇,東郷 史治,佐々木 司
• 学校保健研究 = Japanese journal of school health 61(1), 7-13, 2019-04
• NAID 40021889768

Related Links

• Adolescence | Define Adolescence at Dictionary.com

the transitional period between puberty and adulthood in human development, extending mainly over the teen years and terminating legally when the age of ... adolescence ad·o·les·cence (ād'l-ěs'əns) n. The period of physical and ...

• Adolescence | Psychology Today

Adolescence describes the teenage years between 13 and 19 and can be considered the transitional stage from childhood to adulthood. However, the physical and psychological changes that occur in adolescence can start earlier ...

• Adolescence | Definition of Adolescence by Merriam-Webster

1: the state or process of growing up 2: the period of life from puberty to maturity terminating legally at the age of majority ... Seen and Heard What made you want to look up adolescence? Please tell us where you read or heard it ...

Related Pictures

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★リンクテーブル★

リンク元	「青年期」「pubertal」「pubescent」「youth」「adolescent」
拡張検索	「pregnancy in adolescence」

「青年期」

　　[★]

英

• adolescence、young adulthood、adolescent

関

思春期、青年、ティーンエイジャー、若者

「pubertal」

　　[★]

• adj.

• 思春期の、青春期の

関

adolescence、puberty、pubescence、pubescent

　

「pubescent」

　　[★]

• 思春期の、青春期の

関

adolescence、pubertal、puberty、pubescence

　 　

「youth」

　　[★]

• 若者、若年者

関

adolescence、adolescent、teenager

　 　 　 　 　

「adolescent」

　　[★]

関

adolescence, teenager, young adulthood, youth

　 　 　 　 　 　

「pregnancy in adolescence」

　　[★]

• 思春期妊娠

関

adolescent pregnancy