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Adolescent Development


Evan G. Graber

, DO, Sydney Kimmel Medical College

Last full review/revision Apr 2021| Content last modified Apr 2021

Adolescence is a developmental period during which dependent children grow into independent adults. This period usually begins at about age 10 years and lasts until the late teens or early 20s. During adolescence, children undergo striking physical, intellectual, and emotional growth. Guiding adolescents through this period is a challenge for parents as well as clinicians.

(See also Problems in Adolescents.)

Intellectual and Behavioral Development

In early adolescence, children begin to develop the capacity for abstract, logical thought. This increased sophistication leads to an enhanced awareness of self and the ability to reflect on one’s own being. Because of the many noticeable physical changes of adolescence, this self-awareness often turns into self-consciousness, with an accompanying feeling of awkwardness. The adolescent also has a preoccupation with physical appearance and attractiveness and a heightened sensitivity to differences from peers.

Adolescents also apply their new reflective capabilities to moral issues. Preadolescents understand right and wrong as fixed and absolute. Older adolescents often question standards of behavior and may reject traditions—to the consternation of parents. Ideally, this reflection culminates in the development and internalization of the adolescent’s own moral code.

As adolescents encounter schoolwork that is more complex, they begin to identify areas of interest as well as relative strengths and weaknesses. Adolescence is a period during which young people begin to consider career options, although most do not have a clearly defined goal. Parents and clinicians must be aware of the adolescent’s capabilities, help the adolescent formulate realistic expectations, and be prepared to identify impediments to learning that need remediation, such as learning disabilities, attention problems, behavior problems, or inappropriate learning environments. Parents and clinicians should facilitate apprenticeships and other experiences that expose older adolescents to potential career opportunities either during school or during school vacations. These opportunities may help adolescents focus their career choices and future studies.

Many adolescents begin to engage in risky behaviors, such as fast driving. Many adolescents begin to experiment sexually, and some may engage in risky sexual practices. Some adolescents may engage in illegal activities, such as theft and alcohol and drug use. Experts speculate that these behaviors occur in part because adolescents tend to overestimate their own abilities in preparation for leaving their home. Recent studies of the nervous system also have shown that the parts of the brain that suppress impulses are not fully mature until early adulthood.

Emotional Development in Adolescents

During adolescence, the regions of the brain that control emotions develop and mature. This phase is characterized by seemingly spontaneous outbursts that can be challenging for parents and teachers who often receive the brunt. Adolescents gradually learn to suppress inappropriate thoughts and actions and replace them with goal-oriented behaviors.

The emotional aspect of growth is most trying, often taxing the patience of parents, teachers, and clinicians. Emotional lability is a direct result of neurologic development during this period, as the parts of the brain that control emotions mature. Frustration may also arise from growth in multiple domains.

A major area of conflict arises from the adolescent’s desire for more freedom, which clashes with the parents’ strong instincts to protect their children from harm. Parents may need help in renegotiating their role and slowly allowing their adolescents more privileges as well as expecting them to accept greater responsibility for themselves and within the family.

Communication within even stable families can be difficult and is worsened when families are divided or parents have emotional problems of their own. Clinicians can be of great help by offering adolescents and parents sensible, practical, concrete, supportive help while facilitating communication within the family.

Social and Psychologic Development

The family is the center of social life for children. During adolescence, the peer group begins to replace the family as the child’s primary social focus. Peer groups are often established because of distinctions in dress, appearance, attitudes, hobbies, interests, and other characteristics that may seem profound or trivial to outsiders. Initially, peer groups are usually same-sex but typically become mixed later in adolescence. These groups assume an importance to adolescents because they provide validation for the adolescent’s tentative choices and support in stressful situations.

Adolescents who find themselves without a peer group may develop intense feelings of being different and alienated. Although these feelings usually do not have permanent effects, they may worsen the potential for dysfunctional or antisocial behavior. At the other extreme, the peer group can assume too much importance, also resulting in antisocial behavior. Gang membership is more common when the home and social environments are unable to counterbalance the dysfunctional demands of a peer group.

Clinicians should screen all adolescents for mental health disorders, such as depression, bipolar disorder, and anxiety. Mental health disorders increase in incidence during this stage of life and may result in suicidal thinking or behavior. Psychotic disorders, such as schizophrenia, although rare, most often come to attention during late adolescence. Eating disorders, such as anorexia nervosa and bulimia nervosa, are relatively common among girls and may be difficult to detect because adolescents go to great lengths to hide the behaviors and weight changes.

Substance use typically begins during adolescence. More than 70% of adolescents in the United States try alcohol before they graduate high school. Binge drinking is common and leads to both acute and chronic health risks. Research has shown that adolescents who start drinking alcohol at a young age are more likely to develop an alcohol use disorder as an adult. For example, adolescents who start drinking at age 13 are 5 times more likely to develop an alcohol use disorder than those who start drinking at age 21.

Almost 50% of US adolescents try cigarettes, over 45% try electronic cigarettes (vapes), and more than 43% try marijuana while they are in high school. Use of other drugs is much less common, although misuse of prescription drugs, including drugs for pain and stimulants, is on the rise.

Parents can have a strong positive influence on their children by setting a good example (eg, using alcohol in moderation, avoiding use of illicit drugs), sharing their values, and setting high expectations regarding staying away from drugs. Parents also should teach children that prescription drugs should be used only as directed by a physician. All adolescents should be confidentially screened for substance use. Appropriate advice should be given as part of routine health care because even very brief interventions by physicians and health care practitioners have been shown to decrease substance use by adolescents.

Sexuality and Gender

In addition to adapting to bodily changes, the adolescent must become comfortable with the role of adult and must put sexual urges, which can be very strong and sometimes frightening, into perspective.

As adolescents navigate their sexuality, they may also begin to question their gender identity.

  • Sex refers to a person's biologic status: male, female, or intersex.
  • Sexual orientation refers to the sex to which a person is sexually attracted (if any).
  • Gender identity is the subjective sense of knowing to which gender one belongs; ie, whether people regard themselves as male, female, transgender, or another identifying term (eg, genderqueer, nonbinary, agender).
  • Gender expression is the objective, public expression of gender identity and includes everything that people say and do to indicate to themselves and to others the degree to which they are the gender that they identify with.

Some adolescents struggle with the issue of sexual identity and may be afraid to reveal their sexual or gender identity to friends or family members. Adolescents may feel unwanted or unaccepted by family or peers if they express certain sexual desires or gender identity. Such pressure (especially during a time when social acceptance is critically important) can cause severe stress. Fear of abandonment by parents, sometimes real, may lead to dishonest or at least incomplete communication between adolescents and their parents. These adolescents also can be taunted and bullied by their peers. Threats of physical violence should be taken seriously and reported to school officials or other authorities. The emotional development of adolescents is best helped by supportive clinicians, friends, and family members.

Few elements of the human experience combine physical, intellectual, and emotional aspects as thoroughly as sexuality and all the feelings that go along with it. Helping adolescents put sexuality and gender identity into a healthy context through honest answers regarding reproduction and sexually transmitted diseases is extremely important. Adolescents and their parents should be encouraged to speak openly regarding their attitudes toward sex and sexuality; parents’ opinions remain an important determinant of adolescent behavior.

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