The Developing Person Through Childhood and Adolescence by Kathleen Stassen Berger Seventh Edition Chapter 14 Adolescence: Biosocial Development Slides prepared by Kate Byerwalter, Ph.D., Grand Rapids Community College
Question: What is “Adolescence”? • What age period do you think of when you hear the word “adolescence”? Decide when you think it begins and ends. • What words or images come to your mind when you hear the word “teenager”? Make a list.
Adolescence • Adolescence refers to the age period between childhood and adulthood. • TWEENS: 10-13 years • TEENS: 13-18 years • EMERGING ADULTHOOD: 18-25 yrs
Puberty Begins • Puberty is a period of rapid physical growth and sexual maturation. • The sequence of physical changes is universal, but the timing varies (typically lasting 3-5 years). • Age of onset ranges between 8-15 years.
Puberty Begins (cont.) • Menarche: the term for a girl’s first period. It signals that ovulation has begun (although is often irregular for a few years) • Spermarche: the term for a boy’s first ejaculation, which signals sperm production has begun
Hormones • Puberty begins with a signal from the hypothalamus–to the pituitary gland–to adrenal glands (the HPA axis) and gonads. • Gonads release testosterone and estradiol. • Hormones influence MOOD and THOUGHT.
Sexual Maturation • Primary sex characteristics: • The parts of the body directly involved in reproduction (e.g., testicles, ovaries) • Secondary sex characteristics: • Not necessary for reproduction • Examples: odor, acne, breast development, hair, voice changes
Sudden Emotions • Hormones contribute to the conflict, moodiness, and sexual urges of adolescents, but are not the only cause. • Social and cultural reactions to visible body changes also play a large roll.
Make it Real: Sudden Emotions • Can you recall a time being especially embarrassed or angry during adolescence?
Timing of Puberty JEFF GREENBERG / PHOTOEDIT, INC.
Timing of Puberty • Age of onset of puberty depends on: • GENDER (girls ahead by months or years) • GENES and ETHNICITY • WEIGHT (malnutrition delays puberty) • STRESS (causes puberty earlier)
Quiz: Timing of Puberty • For adolescent girls, do you think it is advantageous to be “early maturing”? • What about for boys? PHOTODISC
Early maturing girls are at higher risk of: Teasing Early sexual activity Eating disorders Early substance use Early maturing boys are at higher risk of: Rebellion Breaking the law Stress and depression from relationships Early Maturation: Correlations
Late Maturation: Correlations • Late maturation may also be difficult, especially for boys in a school in which athletics is valued. • Late maturing girls may feel anxiety about when puberty will hit. (Anyone remember “Are You There God, It’s Me, Margaret” by Judy Blume?)
Bigger and Stronger • The growth spurt is a sudden and rapid period of physical growth during puberty. • Sequence is weight, height, muscles. • Females gain more fat, males gain muscle. • The lungs and heart increase in size.
Other Physical Changes • The lymphoidsystem (tonsils, adenoids) decrease in size. This makes teens less susceptible to asthma and colds. • Skin gets oilier, sweatier, more acne-prone.
Body Rhythms • Most teenagers’ bodies prefer to stay up late and sleep in late. • Teens also tend to get too little sleep for their growing bodies. • Lack of sleep has been associated with higher risk of mood disorders and driving problems.
Make it Real: School Schedules • A few high schools have experimented with later start (and end) times for the school day, with positive results. Would you have liked this idea? What problems might it have created for you? • (Be sure to read your text (p. 442) to find out what the positive results were!)
Make it Real: The Teen Brain • Think of an example of an emotional reaction or impulsive behavior that you have witnessed an adolescent make. • Do you have any explanation WHY the person reacted as they did?
Brain Development in Adolescence • Research has found that the limbic system, an emotional and impulsive part of the brain, develops prior to the prefrontal cortex, the rational, logical part of the brain. • This in part explains some of the impulsive, emotional reactions of teens.
Neural Connections • Myelination of the prefrontal cortex improves with age, fostering improvements in decision making, rational arguments, and even reaction time. • Experiences during adolescence are particularly crucial and lasting.
Make it Real: Healthy or Unhealthy? • In general, would you describe adolescence as a relatively HEALTHY, or UNHEALTHY time of life? RUBBERBALL PRODUCTIONS
Health During Adolescence • In general, adolescence is a HEALTHY age period. • Problem-free reproduction • Peak athletic performance • High energy and endurance • Body systems function at an optimal level • Death by disease is rare (worldwide!)
Health During Adolescence • Unfortunately, teens seem to engage in behaviors that put their health at risk. • The incidence of eatingdisorders has also increased, especially among females. • Fatal accidents, suicides, and homicides are the leading cause of death, especially for males.
A Twisted Memorial DOMINIC CHAVEZ / THE DENVER POST / AP PHOTO
Injury and Death • Accidental deaths during adolescence are likely due to: • Body changes (e.g., testosterone) • Brain changes (e.g., the limbic system) • Social context (e.g., alienation, “macho”)
Question: Sexual Actions • Take a guess: How many teens do you think have had sexual intercourse by age 14? Age 17? RUBBERBALL PRODUCTIONS
Sexual Actions • In the U.S.: • About 25% of teens have had sexual intercourse by age 14 • About 50% by age 17 • About 90% by age 21 • Culture influences how sexually active a teen may be.
Pregnancy in Adolescence • Psychological effects withstanding, the physical toll of pregnancy during adolescence (especially age 15 or younger) is problematic. • Pregnancy may interfere with hormones, height, and nutrition, and the girl’s uterus may be not yet be mature.
Sexually Transmitted Infection • Worldwide, 50% of teens will be have an STI (STD) during adolescence. • Examples: HIV, syphilis, chlamydia, herpes • STI’s can cause later infertility. The risk of serious consequences and reinfection are higher for teens than adults.
Make it Real: Drug Use • What was the atmosphere regarding drug use at your high school, or in your neighborhood? STUART FRANKLIN / MAGNUM PHOTOS
Drug Use • The “Monitoring the Future” study has found that most U.S. teens use alcohol and tobacco before age 18, and about 50% have tried marijuana. • The U.S. has the greatest number of available drugs, although the majority of teens don’t use them.
Question: Drug Use, WHY? • What are some possible reasons an adolescent might use drugs? LAUREN GREENFIELD
Drug use: Why? • Adolescents use drugs for various reasons, including: • The desire to fit in with peers • The thrill of the sensation • As a way to self-medicate • A perceptionthat it is a “normal” part of being a teenager
Drug Use: Long-Term Effects • Some teens move beyond use to abuse (use causing harm) or addiction (physical and psychological need). • The younger a person tries a drug, the more likely addiction will occur (especially for cigarettes).
Drug Use: More Long-Term Effects • Certain drugs may: • Cause cancer • Increase the risk of death by car accident • Interfere with healthy eating and absorption of nutrients (especially tobacco) • Reduce fertility (especially tobacco) • Interfere with brain development (especially alcohol)
Prevention of Drug Use • Prevention efforts such as D.A.R.E. have been found to have no impact on adolescent drug use. • However, increased prices and enforcement of laws have helped reduce cigarette use, specifically.
Nutrition During Adolescence • Teens’ lack ofiron increases the risk of anemia, and impairs muscle development. • Teens’ lack ofcalcium increases the risk of osteoporosis later in life. • Vending machines in schools contribute to poor eating habits among teenagers.
Obesity During Adolescence • About 12% of teenagers are overweight (BMI greater than 25), a higher percentage than in earlier decades. • Lifestyle choices seem to play a large role in this (e.g., lack of exercise, too much TV). • Fast food and soda pop also play a role.
BodyImage • Adolescents report that their body image is the mostimportant predictor of their self-esteem. • Unfortunately, this can lead to eating disorders. PHOTODISC
Anorexia Nervosa • Anorexia involves self starvation. • It is a refusal to maintain at least 85% of a normal Body Mass Index (BMI). • It includes disturbed body perception and denial. • It leads to a number of physical problems, including lack of menstruation (females), and perhaps even death.
Bulimia Nervosa • Bulimia involves repeatedly overeating and then purging via laxatives or vomiting. • Diagnosis requires 1 episode a week for at least 3 months, an uncontrollable urge to overeat, and distorted body image. • Bulimia can cause damage to the gastrointestinal system or death.
Treatment for Eating Disorders • If you are worried about someone with a possible eating disorder: • Get online and EDUCATE YOURSELF about the symptoms and the best ways to help • TALK to the person in a calm, non-judgmental manner. Don’t keep quiet.