1. Adolescence: Body and Mind chapter nine

2. Adolescence One hundred years ago, adolescence began around age 15 and lasted a few months. Now adolescene lasts a decade or more. A separate period called emerging adulthood has been identified. HOLA IMAGES RF/GETTY IMAGES

3. Puberty Average ages and changes Time between the first onrush of hormones and full adult physical development Usually lasting three to five years Many more years are required to achieve psychosocial maturity.

4. Puberty Menarche Girl's first menstrual period, signaling that she has begun ovulation Pregnancy is biologically possible, but ovulation and menstruation are often irregular for years after menarche. Average age—about 12.5 years for normal-weight girls Spermarche Boy's first ejaculation of sperm Erections can occur as early as infancy, but ejaculation signals sperm production Average ag—just under 13 years

5. Puberty Hormones Body chemicals produced by the body to regulate many biological processes. Various hormones influence thoughts, urges, emotions, and behavior. Hormones may underlie differences in psychopathology.

6. Puberty Pituitary gland Gland in the brain that responds to a signal from the hypothalamus by producing many hormones, including those that regulate growth and control other glands, among them the adrenal and sex glands. Adrenal glands Two glands, located above the kidneys, that produce hormones (including the “stress hormones” epinephrine [adrenaline] and norepinephrine).

7. Puberty Begins Gonads Paired sex glands (ovaries in females, testicles in males). Gonads produce hormones and gametes. Estradiol Sex hormone, considered the chief estrogen. Females produce more estradiol than males do. Testosterone Sex hormone, the best known of the androgens (male hormones). Secreted in far greater amounts by males than by females.

8. Remember! The body, brain, and behavior always interact. Sexual thoughts themselves can cause physiological and neurological processes, not just result from them. Rising cortisol levels at puberty increase the likelihood of anger or frustration. Emotions then increase hormones.

9. Body Rhythms Circadian rhythm Day-night cycle of biological activity occurs approximately every 24 hours (circadian means “about a day”). Hormones cause a phase delay in sleep-wake cycles. Biology (circadian rhythms) and culture (parties and technology) work to make teenagers increasingly sleep-deprived with each year of high school.

10. Sleepyheads

11. Opposing Perspectives: Algebra at 7 a.m.? Do adults fight against what is natural to adolescents? Early sleep and early rising expectations with school opening before 8 a.m. –Increases in sleeping during classes, late arrivals, disruptive behaviors, depression SLEEP versus WAKE groups AAP (2014) recommendation –High school classes should not begin until 8:30 or 9:00 a.m. 43% of U.S. high schools do.

12. Dreaming and Learning? This graph shows the percentage of U.S. students who, once a week or more, fall asleep in class or are too tired to exercise. Not shown are those who are too tired overall (59 percent for high school students) or who doze in class “almost every day” (8 percent).

13. Reasons for Variations Genes and gender About two-thirds of the variation in age of puberty is genetic. Genes on the sex chromosomes have a marked effect on age of puberty onset. Girls generally develop ahead of boys. Children who have a relatively large proportion of body fat experience puberty sooner than do their thin contemporaries. Brothers, but Not Twins

14. Reasons for Variations Fat Hormone affects appetite and is believed to be involved in the onset of puberty. In both sexes, chronic malnutrition delays puberty.

15. Puberty Onset Age 11 or 12 is the most likely age of visible onset. The rise in hormone levels that signals puberty is still considered normal in those as young as age 8 or as old as age 14. Higher incidence of precocious puberty (sexual development before age 8) occurs for unknown reasons.

16. Puberty Begins Secular trend Data on puberty over the centuries reveals a dramatic example of a long-term statistical increase or decrease. Each generation has experienced puberty a few weeks earlier, and has grown a centimeter or so taller, than did the preceding one. Secular trend has slowed or stopped in developed nations.

17. Stress Stress hastens the hormonal onset of puberty. Sick, drug-addicted, or divorced parents Violent and impoverished neighborhood Sexual abuse High level of family conflict International adoption at later age Why would cortisol trigger puberty?

18. Puberty Begins Too early, too late Early-maturing girls tend to have lower self- esteem, more depression, and poorer body image than later-maturing girls. Early-maturing boys are more aggressive, law-breaking, and alcohol-abusing than later- maturing boys. Slow developing boys tend to be more anxious, depressed, and afraid of sex.

19. Becoming a Grown-Up Growth spurt A relatively sudden and rapid physical growth that occurs during puberty. Each body part increases in size on a schedule. Height spurt follows the increase in body fat, and then a muscle spurt occurs.

20. Becoming a Grown-Up Growth spurt Lungs triple in weight; consequently, adolescents breathe more deeply and slowly. Heart doubles in size and the heartbeat slows, decreasing the pulse rate while increasing blood pressure. Only lymphoid system (which includes the tonsils and adenoids) decreases in size—teenagers are less susceptible to respiratory ailments.

21. Becoming a Grown-Up Skin and hair Skin becomes oilier, sweatier, and more prone to acne. Hair on the head and limbs becomes coarser and darker. New hair grows under arms, on faces, and over external sex organs. In many ways, hair is more than a growth characteristic; it becomes a display of sexuality.

22. Sexual Maturation Primary sex characteristics Parts of the body that are directly involved in reproduction, including the vagina, uterus, ovaries, testicles, and penis. Secondary sex characteristics Observable physical traits that are not directly involved in reproduction but that indicate sexual maturity, such as a man's beard and a woman's breasts.

23. Nutrition Nutrients missing Family dinners may conflict with adolescent desire for independence. Only 16% of high school seniors eat recommended vegetable servings creating deficiency in intake of necessary vitamins or minerals. Menstruation and intensive physical labor or sports participation may deplete iron (iron-deficiency anemia). For the Audience Teenage eating behavior is influenced by other adolescents.

24. Body Dissatisfaction Body image Person's idea of how his or her body looks –Girls diet partly because boys tend to prefer to date thin girls. –Boys want to look taller and stronger partly because girls value well-developed muscles in males. Self-acceptance is difficult –New changes may contribute to distorted body image, food obsession, depression, and other unhealthy consequences.

25. Eating Disorders Obesity Disorder at every age Rates falling in childhood but increasing in adolescence 2013: 15% of high school students in 22 states were obese. Dieting Erratic eating or ingesting drugs (especially diet pills) to lose weight Taking steroids to increase muscle mass

26. Eating Disorders Anorexia nervosa Eating disorder characterized by self-starvation. Affected individuals voluntarily under-eat and often over-exercise, depriving their vital organs of nutrition. Anorexia can be fatal.

27. Eating Disorder Bulimia nervosa Eating disorder characterized by binge eating and subsequent purging, usually by induced vomiting and/or use of laxatives. In 2013, within previous 6-month period, 6.6% of U.S. high school girls and 2.2% of boys vomited or took laxatives for weight loss.

28. Eating Disorders Binge eating disorder Eating disorder characterized by periodic and compulsive overeating until stomach hurts Eating done secretly at least weekly for months; no purging Sufferer feels out of control, distressed, and depressed.

29. Thinking, Fast and Slow Different parts of the brain grow at different rates. Limbic system (fear, emotional impulses) matures before the prefrontal cortex (planning ahead, emotional regulation). Emotional areas develop before the reflective ones do.

30. Same People, But Not the Same Brain NITIN GOGTAY, ET AL. PROC NATL ACAD SCI U S A. 2004 MAY 25;101(21):8174–8179. © 2004 NATIONAL ACADEMY OF SCIENCES, U.S.A.

31. Cognitive Development Logic shut down When emotions are intense, especially when one is with peers, the logical part of the brain shuts down. When stress, arousal, passion, sensory bombardment, drug intoxication, or deprivation is extreme, the adolescent brain is overtaken by impulses that might shame adults. How might this affect teen texting while driving?

32. A View from Science: The Pleasures of the Adolescent Brain On average, sensation- seeking accelerates rapidly at puberty, and sensation- seeking and impulsivity slowly decline with maturation. As you can see to the right, adolescents become less impulsive as they mature, but they still enjoy the thrill of a new sensation. Look Before You Leap

33. Benefits of Adolescent Brain Development Increased mylenation and slower inhibition increases reaction time. Activation of positive neurotransmitters promotes pleasurable experiences. Synaptic growth, enhancing moral development and openness to new experiences and ideas

34. Cognitive Development Formal operational thought: Piaget Fourth and final stage of cognitive development Characterized by more systematic logic and the ability to think about abstract ideas

35. Thinking About Oneself Assumptions that have no necessary relation to reality Adolescent egocentrism Personal fable Invincibility fable Imaginary audience

36. Piaget’s Experiments What does Piaget’s balance-scale test of formal reasoning reveal about cognition?

37. Cognitive Development Deductive reasoning Reasoning from a general statement, premise, or principle, through logical steps, to figure out (deduce) specifics Sometimes called top-down reasoning Inductive reasoning Reasoning from one or more specific experiences or facts to a general conclusion; may be less cognitively advanced than deduction Sometimes called bottom-up reasoning Hypothetical thought Reasoning that includes propositions and possibilities that may not reflect reality

38. Two Modes of Thinking Dual-process model The idea that two modes of thinking exist within the human brain, one for intuitive emotional responses and one for analytical reasoning

39. Cognitive Development Intuitive thought Thought that arises from an emotion or a hunch, beyond rational explanation, and is influenced by past experiences and cultural assumptions Analytic thought Thought that results from analysis, such as a systematic ranking of pros and cons, risks and consequences, possibilities and facts Analytic thought depends on logic and rationality.

40. Technology and Cognition Today’s teens are digital natives. Most secondary school students use technology. Educators claim the most difficult aspect of technology is teaching how to evaluate information sources. Internet use is not included as an addiction in DSM-5. Digital Natives

41. Abuse and Addiction Decline in number of teenagers exposed to online sexual predators; most likely to be younger, known person Adults may pathologize normal teen behavior.

42. Cyber Danger Cyberbullying Bullying that occurs via Internet insults, rumors, texting, anonymous phone calls, and video embarrassment Anonymity provided by electronic technology often brings out the worst in people. Cyberbullying is similar to other forms in intent or degree of harm.

43. Sexting Sexting involves sending sexual photographs –Estimated 30 percent of adolescents have sent sexual photographs. Dangers –Forwarding pictures without sender’s knowledge –Experiencing depression if the reaction is negative

44. Teaching and Learning Secondary education Period after primary education (elementary or grade school) and before tertiary education (college) Usually occurs from about age 11 to age 18, although the age range varies somewhat by school and by nation

45. School Transitions Entering a new school Transition from one school to another often impairs a young person's ability to function and learn. Changing schools just when the growth spurt is occurring and sexual characteristics are developing is bound to create stress.

46. Teaching and Learning Middle school School for children after elementary school and before high school, usually grades 6 through 8 Often a developmental mismatch between student needs and school context –Increased bullying –Complicated friendships –Parental underestimation of daily stress –Academic excellence recognition may be challenging

47. Coping with Middle School Student, parent, school, and cultural interpretation of intellectual achievement Entity theory of intelligence –Sees ability as innate, a fixed quantity present at birth –Rejects idea that effort enhances achievement Incremental theory of intelligence –Poses intelligence can be directly increased by effort –Believe they can master whatever they seek to learn if they pay attention, participate in class, study, and complete their homework

48. Older Adolescents in School College bound In theory and sometimes in practice, high schools promote students' analytic ability. In U.S., an increasing number of high school students are enrolled in classes that are designed to be more rigorous and that require them to pass externally scored exams. –AP and IB

49. Teaching and Learning High-stakes test Evaluation that is critical in determining success or failure Determines if a student will graduate or be promoted Used by 24 U.S. states (74% of high school students)

50. Mostly Good News

51. Measuring Practical Cognition PISA (Programme for International Student Assessment) International test taken by 15-year-olds in 50 nations that is designed to measure problem-solving and cognition in daily life U.S. students perform lower on the PISA compared to many other nations (in the 2012 assessments). The PISA and international comparisons of high-school dropout rates suggest that U.S. secondary education can be improved, especially for those who do not go to college..