Adolescence: A Developmental Transition

Guidepost 1 What is adolescence, and when does it begin and end?

• Adolescence is the transition from childhood to adulthood. Neither its beginning nor its end is clearly marked in western societies; it lasts about a decade, between ages 11 or 12 and the late teens or early twenties.
• Legal, sociological, and psychological definitions of entrance into adulthood vary. In some nonwestern cultures, "coming of age" is signified by special rites.

Guidepost 2 What opportunities and risks does adolescence entail?

• Adolescence is full of opportunities for physical, cognitive, and psychosocial growth, but also of risks to healthy development. Risky behavior patterns, such as drinking alcohol, drug abuse, sexual and gang activity, and use of firearms tend to be established early in adolescence. About 4 out of 5 young people experience no major problems.

Puberty: The End of Childhood

Guidepost 3 What physical changes do adolescents experience, and how do these changes affect them psychologically?

• Puberty is triggered by hormonal changes, which may affect moods and behavior. Puberty takes about four years, typically begins earlier in girls than in boys, and ends when a person can reproduce.
• During puberty, both boys and girls undergo an adolescent growth spurt. A secular trend toward earlier attainment of adult height and sexual maturity began about 100 years ago, probably because of improvements in living standards.
• Primary sex characteristics (the reproductive organs) enlarge and mature during puberty. Secondary sex characteristics also appear.
• The principal signs of sexual maturity are production of sperm (for males) and menstruation (for females). Spermarche typically occurs at age 13. Menarche occurs, on average, between the ages of 12 and 13 in the United States.
• Sexual attraction seems to begin at about age 10, when the adrenal glands increase their hormonal output.
• Teenagers, especially girls, tend to be sensitive about their physical appearance. Girls who mature early tend to adjust less easily than early maturing boys.

Physical and Mental Health

Guidepost 4 What are some common health problems in adolescence, and how can they be prevented?

• For the most part, the adolescent years are relatively healthy. Health problems often are associated with poverty or a risk-taking lifestyle. Adolescents are less likely than younger children to get regular medical care.
• Many adolescents, especially girls, do not engage in regular vigorous physical activity.
• Many adolescents do not get enough sleep because the high school schedule is out of sync with their natural body rhythms.
• Three common eating disorders in adolescence are obesity, anorexia nervosa, and bulimia nervosa. All can have serious long-term effects. Anorexia and bulimia affect mostly girls. Outcomes for bulimia tend to be better than for anorexia.
• Adolescent substance abuse and dependence have lessened in recent years; still, drug use often begins as children move into middle school.
• Marijuana, alcohol, and tobacco are the most popular drugs with adolescents. All involve serious risks and can be gateways to the use of hard drugs.
• Rates of sexually transmitted diseases (STDs) in the United States are highest in the world, and especially high among adolescents. STDs are more likely to develop undetected in girls than in boys.
• Maltreatment of adolescents can lead to serious behavior problems.
• Leading causes of death among adolescents include motor vehicle accidents, firearm use, and suicide.