Physical Development in Adolescence
During puberty, an adolescent experiences a period of rapid physical growth that culminates in sexual maturity.
Review the milestones of physical development in adolescence
- Adolescence is the period of development that begins at puberty and ends at emerging adulthood; the typical age range is from 12 to 18 years, and this stage of development has some predictable physical milestones.
- Puberty involves distinctive physiological changes in an individual’s height, weight, body composition, sex characteristics, and circulatory and respiratory systems. These changes are largely influenced by hormonal activity.
- During puberty, the adolescent develops secondary sex characteristics (such as a deeper voice in males and the development of breasts and hips in females) as their hormonal balance shifts strongly towards an adult state.
- The adolescent growth spurt is a rapid increase in an individual’s height and weight during puberty resulting from the simultaneous release of growth hormones, thyroid hormones, and androgens.
- Because rates of physical development vary so widely among teenagers, puberty can be a source of pride or embarrassment.
- menarche: The onset of menstruation in human females; the beginning of the menstrual period.
- puberty: The age at which a person is first capable of sexual reproduction.
- gonad: A sex organ that produces gametes; specifically, a testicle or ovary.
Adolescence is a socially constructed concept. In pre-industrial society, children were considered adults when they reached physical maturity; however, today we have an extended time between childhood and adulthood known as adolescence. Adolescence is the period of development that begins at puberty and ends at emerging adulthood; the typical age range is from 12 to 18 years, and this stage of development has some predictable physical milestones.
Physical Changes of Puberty
Puberty is the period of several years in which rapid physical growth and psychological changes occur, culminating in sexual maturity. The onset of puberty typically occurs at age 10 or 11 for females and at age 11 or 12 for males; females usually complete puberty by ages 15 to 17, while males usually finish around ages 16 to 17. Females tend to attain reproductive maturity about four years after the first physical changes of puberty appear. Males, however, accelerate more slowly but continue to grow for about six years after the first visible pubertal changes. While the sequence of physical changes in puberty is predictable, the onset and pace of puberty vary widely. Every person’s individual timetable for puberty is different and is primarily influenced by heredity; however environmental factors—such as diet and exercise—also exert some influence.
Puberty involves distinctive physiological changes in an individual’s height, weight, body composition, and circulatory and respiratory systems. During this time, both the adrenal glands and the sex glands mature—processes known as adrenarche and gonadarche, respectively.
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 (triggering certain behavioral and physical changes). During puberty, the adolescent’s hormonal balance shifts strongly towards an adult state; the process is triggered by the pituitary gland, which secretes a surge of hormonal agents into the blood stream and initiates a chain reaction.
It is this stage in life in which a child develops secondary sex characteristics. Primary sex characteristics are organs specifically needed for reproduction, like the uterus and ovaries in females and the testes in males. Secondary sex characteristics, on the other hand, are physical signs of sexual maturation that do not directly involve sex organs. In females, this includes development of breasts and widening of hips, while in males it includes development of facial hair and deepening of the voice. Both sexes experience development of pubic and underarm hair, as well as increased development of sweat glands.
The male and female gonads are activated by the surge of hormones, which puts them into a state of rapid growth and development. The testes primarily release testosterone, and the ovaries release estrogen; the production of these hormones increases gradually until sexual maturation is met. Girls experience menarche, the beginning of menstrual periods, usually around 12–13 years old, and boys experience spermarche, the first ejaculation, around 13–14 years old. Facial hair in males typically appears around age 14.
The adolescent growth spurt is a rapid increase in an individual’s 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 than females. 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 (head, hands, and feet), followed by the arms and legs, and later the torso and shoulders. This non-uniform growth is one reason why an adolescent body may seem out of proportion. During puberty, bones become harder and more brittle.
Before puberty, there are nearly no differences between males and females in the distribution of fat and muscle. During puberty, males grow muscle much faster than females, and females experience a higher increase in body fat. The ratio between muscle and fat in post-pubertal males is around 1:3, while for males it is about 5:4. An adolescent’s heart and lungs increase in both size and capacity during puberty; these changes contribute to increased strength and tolerance for exercise.
The adolescent brain also remains under development during this time. Adolescents often engage in increased risk-taking behaviors and experience heightened emotions during puberty; this may be due to the fact that the frontal lobes of their brains—which are responsible for judgment, impulse control, and planning—are still maturing until early adulthood (Casey, Tottenham, Liston, & Durston, 2005).
Effects of Physical Development
Because rates of physical development vary so widely among teenagers, puberty can be a source of pride or embarrassment. Early maturing boys tend to be physically stronger, taller, and more athletic than their later maturing peers; this can contribute to differences in popularity among peers, which can in turn influence the teenager’s confidence. Some studies show that boys who mature earlier tend to be more popular and independent but are also at a greater risk for substance abuse and early sexual activity (Flannery, Rowe, & Gulley, 1993; Kaltiala-Heino, Rimpela, Rissanen, & Rantanen, 2001). Early maturing girls may face increased teasing and sexual harassment related to their developing bodies, which can contribute to self-consciousness and place them at a higher risk for anxiety, depression, substance abuse, and eating disorders (Ge, Conger, & Elder, 2001; Graber, Lewinsohn, Seeley, & Brooks-Gunn, 1997; Striegel-Moore & Cachelin, 1999). Girls and boys who develop more slowly than their peers may feel self-conscious about their lack of physical development; some research has found that negative feelings are particularly a problem for late maturing boys, who are at a higher risk for depression and conflict with parents (Graber et al., 1997) and more likely to be bullied (Pollack & Shuster, 2000).
Cognitive Development in Adolescence
In adolescence, changes in the brain interact with experience, knowledge, and social demands and produce rapid cognitive growth.
Review the milestones of cognitive development in adolescence
- Jean Piaget describes adolescence as the stage of life in which the individual’s thoughts start taking more of an abstract form and egocentric thoughts decrease. This allows the adolescent to think and reason with a wider perspective.
- The constructivist perspective, based on the work of Piaget, takes a quantitative, state-theory approach, hypothesizing that adolescents’ cognitive improvement is relatively sudden and drastic.
- The information-processing perspective 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 basic thinking abilities generally occur in five areas during adolescence: attention, memory, processing speed, organization, and metacognition.
- Metacognition is relevant in social cognition, resulting in increased introspection, self-consciousness, and intellectualization. Adolescents are more likely to question others’ assertions and less likely to accept facts as absolute truths.
- Wisdom, or the capacity for insight and judgment that is developed through experience, increases between the ages of 14 and 25; however, the tendency toward risk-taking also increases during adolescence.
- relativistic: Of or relating to the concept that points of view have no absolute truth or validity, and instead have only subjective value according to differences in perception.
- mnemonic device: Any specific learning technique that aids information retention.
- prefrontal cortex: The anterior part of the frontal lobes of the brain, lying in front of the motor and premotor areas; a part of the brain associated with higher cognition.
- introspection: A looking inward; the act or process of self-examination, or inspection of one’s own thoughts and feelings; the cognition that the mind has of its own acts and states; self-consciousness.
- egocentric: Self-centered; absorbed with the self; selfish.
intellectualization: The act or process of finding a seemingly rational explanation for something.
Cognitive Development and Changes in the Brain
Adolescence is a time for rapid cognitive development. Cognitive theorist Jean Piaget describes adolescence as the stage of life in which the individual’s thoughts start taking more of an abstract form and egocentric thoughts decrease. This allows an individual to think and reason with a wider perspective. This stage of cognitive development, termed by Piaget as the formal operational stage, marks a movement from an ability to think and reason from concrete visible events to an ability to think hypothetically and entertain what-if possibilities about the world. An individual can solve problems through abstract concepts and utilize hypothetical and deductive reasoning. Adolescents use trial and error to solve problems, and the ability to systematically solve a problem in a logical and methodical way emerges.
Biological changes in brain structure and connectivity in the brain interact with increased experience, knowledge, and changing social demands to produce rapid cognitive growth. These changes generally begin at puberty or shortly thereafter, and some skills continue to develop as an adolescent ages. Development of executive functions, or cognitive skills that enable the control and coordination of thoughts and behavior, are generally associated with the prefrontal cortex area of the brain. The thoughts, ideas, and concepts developed at this period of life greatly influence one’s future life and play a major role in character and personality formation.
Perspectives and Advancements in Adolescent Thinking
There are two perspectives on adolescent thinking: constructivist and information-processing. The constructivist perspective, based on the work of Piaget, takes a quantitative, state-theory approach. This view hypothesizes that adolescents’ cognitive improvement is relatively sudden and drastic. The information-processing perspective derives from the study of artificial intelligence and explains cognitive development in terms of the growth of specific components of the overall process of thinking.
Improvements in basic thinking abilities generally occur in five areas during adolescence:
- Attention. Improvements are seen in selective attention (the process by which one focuses on one stimulus while tuning out another), as well as divided attention (the ability to pay attention to two or more stimuli at the same time).
- Memory. Improvements are seen in both working memory and long-term memory.
- Processing Speed. Adolescents think more quickly than children. Processing speed improves sharply between age five and middle adolescence, levels off around age 15, and does not appear to change between late adolescence and adulthood.
- Organization. Adolescents are more aware of their own thought processes and can use mnemonic devices and other strategies to think more efficiently.
- Metacognition. Adolescents can think about thinking itself. This often involves monitoring one’s own cognitive activity during the thinking process. Metacognition provides the ability to plan ahead, see the future consequences of an action, and provide alternative explanations of events.
Metacognition and Relativistic Thinking
Metacognition is relevant in social cognition and results in increased introspection, self-consciousness, and intellectualization. Adolescents are much better able to understand that people do not have complete control over their mental activity. Being able to introspect may lead to two forms of egocentrism, or self-focus, in adolescents, which result in two distinct problems in thinking: the imaginary audience (when an adolescent believes everyone is listening to him or her) and the personal fable (which causes adolescents to feel that nothing harmful could ever happen to them). 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.
Adolescents are more likely to engage in relativistic thinking—in other words, they are more likely to question others’ assertions and less likely to accept information as absolute truth. Through experience outside the family circle, they learn that rules they were taught as absolute are actually relativistic. They begin to differentiate between rules crafted from common sense (don’t touch a hot stove) and those that are based on culturally relative standards (codes of etiquette). This can lead to a period of questioning authority in all domains.
Wisdom and Risk-Taking
Wisdom, or the capacity for insight and judgment that is developed through experience, increases between the ages of 14 and 25, then levels off. Wisdom is not the same as intelligence, and adolescents do not improve substantially on IQ tests since their scores are relative to others in their age group, as everyone matures at approximately the same rate.
Adolescents are more likely to take risks than adults. The behavioral decision-making theory proposes that adolescents and adults both weigh the potential rewards and consequences of an action. However, adolescents seem to give more weight to rewards, particularly social rewards, than do adults.
Socioemotional Development in Adolescence
Adolescence is a period of personal and social identity formation, in which different roles, behaviors, and ideologies are explored.
Review the milestones of socioemotional development in adolescence
- Adolescence is the period of life known for the formation of personal and social identity. Adolescents must explore, test limits, become autonomous, and commit to an identity, or sense of self.
- Erik Erikson referred to the task of the adolescent as one of identity versus role confusion. Thus, in Erikson’s view, an adolescent’s main questions are “Who am I?” and “Who do I want to be?”
- Early in adolescence, cognitive developments result in greater self-awareness, the ability to think about abstract, future possibilities, and the ability to consider multiple possibilities and identities at once.
- Changes in the levels of certain neurotransmitters (such as dopamine and serotonin) influence the way in which adolescents experience emotions, typically making them more emotional and more sensitive to stress.
- When adolescents have advanced cognitive development and maturity, they tend to resolve identity issues more easily than peers who are less cognitively developed.
- As adolescents work to form their identities, they pull away from their parents, and the peer group becomes very important; despite this, relationships with parents still play a significant role in identity formation.
- egocentric: Self-centered; concerned with the self; selfish.
- differentiation: The act of distinguishing or describing a thing; exact definition or determination.
- self-esteem: Confidence in one’s own worth; self-respect.
Adolescence is the period of development that begins at puberty and ends at emerging adulthood; the typical age range is from 12 to 18 years, and this stage of development has some predictable psychosocial milestones. In the United States, adolescence is seen as a time to develop independence from parents while remaining connected to them.
Adolescent Identity Exploration
Adolescence is the period of life known for the formation of personal and social identity. Adolescents must explore, test limits, become autonomous, and commit to an identity, or sense of self. Different roles, behaviors, and ideologies must be tried out to select an identity, and adolescents continue to refine their sense of self as they relate to others. Erik Erikson referred to the task of the adolescent as one of identity versus role confusion. Thus, in Erikson’s view, an adolescent’s main questions are “Who am I?” and “Who do I want to be?” Some adolescents adopt the values and roles that their parents provide them with; other teens develop identities that are in opposition to their parents but align with a peer group. This is common, as peer relationships become a central focus in adolescents’ lives.
Adolescents tend to be rather egocentric; they often experience a self-conscious desire to feel important in peer groups and receive social acceptance. Because choices made during adolescence can influence later life, higher levels of self-awareness and self-control in mid-adolescence will contribute to better decisions during the transition to adulthood. Three general approaches to understanding identity development include self-concept, sense of identity, and self-esteem.
Early in adolescence, cognitive developments result in greater self-awareness. This leads to greater awareness of others as well as one’s own thoughts and judgments. Adolescents develop the ability to think about abstract, future possibilities and consider multiple possibilities at once. They can conceptualize multiple possible selves that they could become, as well as long-term possibilities and consequences of their choices. Adolescents can begin to qualify their traits when asked to describe themselves. Differentiation occurs as an adolescent recognizes and distinguishes the contextual factors that influence their own behavior and the perceptions of others. Differentiation becomes fully developed by mid-adolescence.
The recognition of inconsistencies in the self-concept is a common source of distress during these years; however, this distress may benefit adolescents by encouraging further development and refinement of their self-concept.
Sense of Identity
Unlike the conflicting aspects of self-concept, identity represents a coherent sense of self that is stable across circumstances and includes past experiences and future goals. Erikson determined that “identity achievement” resolves the identity crisis in which adolescents must explore different possibilities and integrate different parts of themselves before committing to their chosen identity. Adolescents begin by defining themselves based on their membership in a group and then focus in on a personal identity.
Self-esteem consists of one’s thoughts and feelings about one’s self-concept and identity. In the United States, children who are raised female are often taught that their sense of self is highly linked to their relationships with others; therefore, many adolescent girls enjoy high self-esteem when engaged in supportive relationships with friends. The most important function of friendship here is having someone who can provide social and moral support. Children who are raised as male, on the other hand, are often taught to value such things as autonomy and independence; therefore, many adolescent boys are more concerned with establishing and asserting their independence and defining their relation to authority. High self-esteem is often derived from their ability to successfully influence their friends.
During puberty, adolescents experience changes in the levels of certain neurotransmitters (such as dopamine and serotonin) in the limbic system. This affects the way in which they experience emotions, typically making them more emotional than younger children and adults and more sensitive to rewards and stress.
Other cognitive developments have an impact on identity formation as well. When adolescents are able to think abstractly and reason logically, they have an easier time exploring and contemplating possible identities. When adolescents have advanced cognitive development and maturity, they tend to resolve identity issues more easily than peers who are less cognitively developed.
As adolescents work to form their identities, they pull away from their parents, and the peer group becomes very important (Shanahan, McHale, Osgood, & Crouter, 2007). Despite spending less time with their parents, the type of relationship that adolescents have with their parents still plays a significant role in identity formation. Warm and healthy parent-child relationships have been associated with positive child outcomes, such as better grades and fewer school-behavior problems, in the United States as well as in other countries (Hair et al., 2005). When a solid and positive relationship exists, adolescents are more likely to feel freedom in exploring identity options. However, when the relationship is not as close or supportive and/or the adolescent fears rejection from the parent, the adolescent is more likely to feel less confident in forming a separate, personal identity.
Cultural and Societal Influences on Adolescent Development
The influence of parental and peer relationships, as well as the broader culture, shapes many aspects of adolescent development.
Examine the influence of culture and society on adolescent development
- The relationships adolescents have with their peers, family, and members of their social sphere play a vital role in their development.
- As adolescents work to form their identities, they pull away from their parents, and the peer group becomes very important. Adolescence can be a time of increased conflict between parents and their children.
- Peer groups offer their members the opportunity to develop social skills; however, they can also be the source of negative influences, such as peer pressure.
- Culture is learned and socially shared and affects all aspects of an individual’s life. Social responsibilities, sexual expression, and belief-system development are all things that are likely to vary by culture.
- Adolescents develop unique belief systems through their interaction with social, familial, and cultural environments. The attitudes that a culture holds on a particular topic can have both positive and negative impacts on adolescent development.
- norms: That which is regarded as normal or typical; a rule that is enforced by members of a community.
- adolescence: The transitional period of physical and psychological development between childhood and maturity.
- peer pressure: Encouragement by others in one’s age group to act or behave in a certain way.
- puberty: The period during which a person first becomes capable of sexual reproduction.
The relationships adolescents have with their peers, family, and members of their social sphere play a vital role in their development. Adolescence is a crucial period in social development, as adolescents can be easily swayed by their close relationships. Research shows there are four main types of relationships that influence an adolescent: parents, peers, community, and society.
When children go through puberty in the United States, there is often a significant increase in parent-child conflict and a decrease in cohesive familial bonding. Arguments often concern new issues of control, such as curfew, acceptable clothing, and the right to privacy. Parent-adolescent disagreement also increases as friends demonstrate a greater impact on the child; this is especially true when parents do not approve of new friends’ values or behaviors.
While adolescents strive for freedom, the unknowns can be frightening for parents. Although conflicts between children and parents increase during adolescence, they are often related to relatively minor issues. Regarding more important life issues, many adolescents will still share the same attitudes and values as their parents. Adolescents who have a good relationship with their parents are less likely to engage in various risky behaviors, such as smoking, drinking, fighting, and/or unprotected sex.
As adolescents work to form their identities, they pull away from their parents, and the peer group becomes very important (Shanahan, McHale, Osgood, & Crouter, 2007). The level of influence that peers can have over an adolescent makes these relationships particularly important in personal development. As children begin to create bonds with various people, they start to form friendships; high quality friendships may enhance a child’s development regardless of the particular characteristics of those friends. Adolescents 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 of the group the opportunity to develop social skills such as empathy, sharing, and leadership. Peer groups can have positive influences on an individual, such as academic motivation and performance; however, they can also have negative influences, such as peer pressure to engage in drug use, drinking, vandalism, stealing, or other risky behavior. Susceptibility to peer pressure increases during early adolescence, and while peers may facilitate positive social development for one another, they may also hinder it. Emotional reactions to problems and emotional instability—both characteristic of the hormonal changes in adolescence—have been linked with physical aggression among peers. Research has linked both physical and relational aggression to a vast number of enduring psychological difficulties, including depression.
Community, Society, and Culture
There are certain characteristics of adolescent development that are more rooted in culture than in human biology or cognitive structures. Culture is learned and socially shared, and it affects all aspects of an individual’s life. Social responsibilities, sexual expression, and belief-system development, for instance, are all likely to vary based on culture. Furthermore, many distinguishing characteristics of an individual (such as dress, employment, recreation, and language) are all products of culture.
Many factors that shape adolescent development vary by culture. For instance, the degree to which adolescents are perceived as autonomous, or independent, beings varies widely in different cultures, as do the behaviors that represent this emerging autonomy. The lifestyle of an adolescent in a given culture is also profoundly shaped by the roles and responsibilities he or she is expected to assume. The extent to which an adolescent is expected to share family responsibilities, for example, is one large determining factor in normative adolescent behavior. Adolescents in certain cultures are expected to contribute significantly to household chores and responsibilities, while others are given more freedom or come from families with more privilege where responsibilities are fewer. Differences between families in the distribution of financial responsibilities or provision of allowance may reflect various socioeconomic backgrounds, which are further influenced by cultural norms and values.
Adolescents begin to develop unique belief systems through their interaction with social, familial, and cultural environments. These belief systems encompass everything from religion and spirituality to gender, sexuality, work ethics, and politics. The range of attitudes that a culture embraces on a particular topic affects the beliefs, lifestyles, and perceptions of its adolescents, and can have both positive and negative impacts on their development. In the United States and many other parts of the world, lesbian, gay, bisexual, transgender, and queer (LGBTQ) youth face much discrimination and bullying by their peers based on the broader cultural attitudes about LGBTQ issues; many are ostracized from peer groups because they are seen to be breaking culturally based gender norms. This can have a tremendous impact on the development of queer or transgender adolescents, increasing their risk for depression, anxiety, and even suicide. Similarly, early-maturing girls may suffer teasing or sexual harassment related to their developing bodies, contributing to a higher risk of depression, substance abuse, and eating disorders (Ge, Conger, & Elder, 2001; Graber, Lewinsohn, Seeley, & Brooks-Gunn, 1997; Striegel-Moore & Cachelin, 1999).