Chapter 11

• Adolescence


  A developmental transition that involves physical, cognitive, emotional, and social changes and takes varying forms in different social, cultural, and economic settings
• Puberty


  The process that leads to sexual maturity, or fertility - the ability to reproduce
• 13 years old was the age where adolescence and puberty were thought to begin
• Puberty


  • Signals the end of childhood
  • Rapid growth in height and weight, changes in body proportions and form, and attainment of sexual maturity
  • Results from heightened production of sex-related hormones and takes place in two stages: Adrenarche (maturing of the adrenal glands) and Gonadarche (maturing of the sex organs)
• Adrenarche


  The maturing of the adrenal glands
• Gonadarche


  The maturing of the sex organs (testes or ovaries)
• DHEA


  A hormone that plays a part in the growth of pubic, axillary (armpit), facial hair, faster body growth, oilier skin, and the development of body odor
• Leptin


  A hormone in the bloodstream having a role in obesity, may stimulate the hypothalamus to signal the pituitary gland, which in turn may signal the sex glands to increase their secretion of hormones
• Hormonal activity depend on reaching a critical amount of body fat necessary for successful reproduction
• The heightened emotionality and moodiness of early adolescence is due to these hormonal developments
• Sequence of physiological changes in adolescence - Female

  • Growth of breast
  • Growth of pubic hair
  • Body growth
  • Menarche (first menstruation)
  • Appearance of underarm hair
• Sequence of physiological changes in adolescence - Male

  • Growth of testes, scrotal sac
  • Growth of pubic hair
  • Body growth
  • Growth of penis, prostate gland, seminal vesicles
  • Change in voice
  • First ejaculation of semen
  • Appearance of facial and underarm hair
• Primary sex characteristics


  The organs necessary for reproduction, which enlarge and mature during adolescence
• Primary sex characteristics - Female

  • Ovaries
  • Fallopian tubes
  • Uterus
  • Clitoris
  • Vagina
• Primary sex characteristics - Male

  • Testes
  • Penis
  • Scrotum
  • Seminal vesicles
  • Prostate gland
• Secondary sex characteristics


  Physiological signs of sexual maturation that do not directly involve the sex organs (breasts of females and the broad shoulders of males, changes in the voice and skin texture, muscular development, pubic, facial, and axillary hair)
• Signs of puberty


  • Breast tissue and pubic hair in girls
  • Enlargement of the testes in boys
  • Enlargement and protrusion of a girl's nipples and areolae
  • Temporary breast enlargement in some adolescent boys
  • Voice deepening in boys
  • Skin becoming coarser and oilier
  • Sebaceous glands leading to pimples and blackheads
  • Acne being more common in boys due to increased testosterone
• Adolescent growth spurt


  A rapid increase in height, weight, and muscle and bone growth that occurs during puberty, typically lasting about two years
• Girls' growth spurt begins between 9 1/2 and 14 1/2 (usually at about 10), while boys' begins between 10 1/2 and 16 (usually at 12 or 13)
• Spermarche


  The first ejaculation that occurs at an average age of 13, including nocturnal emissions (wet dreams)
• Menarche


  The first menstruation, which is a monthly shedding of tissue from the lining of the womb
• Secular trend


  A trend toward earlier attainment of adult height and sexual maturity that can be seen only by observing several generations
• Healthier, better nourished, and better cared for children might be expected to mature earlier and grow bigger
• A combination of genetic, physical, emotional, and contextual influences including environmental toxics, diet, exercise, body weight, and chronic illness or stress, may affect individual differences in the timing of menarche
• Adolescent brain


  • Dramatic changes in the brain structures involved in emotions, judgment, organization of behavior, and self-control
  • Early adolescents (ages 11-13) tended to use the amygdala which is heavily involved in emotional and instinctual reactions
  • Older adolescents (ages 14-17) used the frontal lobes, which handle planning, reasoning, judgment, emotional regulation, and impulse control, and thus permit more accurate, reasoned judgments
• Changes in the structure and composition of the frontal cortex in adolescence

  • Increase in white matter typical of childhood brain development continues in the frontal lobes
  • Pruning of unused dendritic connections during childhood results in a reduction in density of gray matter (nerve cells), increasing the brain's efficiency
• Cognitive stimulation


  A young person's activities and experiences determine which neuronal connections will be retained and strengthened, and this development supports further cognitive growth in those areas
• Benefits of regular exercise

  • Improved strength and endurance
  • Healthier bones and muscles
  • Reduced anxiety and stress
  • Increased self-esteem, school grades, and well-being
• A sedentary lifestyle may result in increased risk of obesity, type II diabetes, heart disease and cancer
• Sleep deprivation among adolescents has been called an epidemic, as they generally go to sleep later and sleep less on school days the older they get
• Adolescents need as much or more sleep than when they were younger, and sleep deprivation can sap motivation, cause irritability, and affect concentration and school performance
• Eating disorders and obesity

  • Eating disorders, including obesity, are most prevalent in industrialized societies, where food is abundant and attractiveness is equated with slimness
  • Overweight teenagers tend to be in poorer health and are more likely to have difficulty attending school, performing household chores, or engaging in strenuous activity or personal care
  • They are at heightened risk of high cholesterol, hypertension, and diabetes
• Body image and eating disorders

  • As girls' body fat increase during puberty, many girls become unhappy about their appearance, reflecting the cultural emphasis on female physical attributes
  • Girls' dissatisfaction with their bodies increases during early to mid-adolescence, whereas boys becoming more muscular are more satisfied with their bodies
  • Parental attitudes and media images can play a greater part than peer influences in encouraging weight concerns
• Bulimia nervosa


  • Goes on huge, eating binges, and then may try to purge the high caloric intake through self-induced vomiting, strict dieting or fasting, excessively vigorous exercise, or laxatives, enemas, or diuretics
  • People who binge frequently tend to be overweight and to experience emotional distress and other medical and psychological disorders
• Substance use and abuse

  • Substance use often begin when children enter middle school, where they become more vulnerable to peer pressure
  • Fourth to sixth graders may start using cigarettes, beer, and inhalants and as they get older, may move on to marijuana or harder drugs
  • Smoking often begin in the early teenage years as a sign of toughness, rebelliousness, and passage from childhood to adulthood
  • The rise of nonmedical use of prescription drugs, such as sedatives, tranquilizers, and narcotic pain relievers, particularly OxyContin and Vicodin are also observed
• Substance abuse


  The harmful use of alcohol or other drug that can lead to substance dependence or addiction
• Addictive drugs


  Dangerous for adolescents because they stimulate parts of the brain that are still developing in adolescence
• Alcohol


  • A potent, mind-altering drug with major effects on physical, emotional, and social well-being
  • Alcohol abusers who stopped drinking showed cognitive impairments weeks later
• Marijuana


  • Typically contains more than 400 carcinogens, and its potency has doubled in the past 25 years
  • Heavy use can damage the brain, heart, lungs, and immune system