Development and PubertyPhysical ChangesWeight, Height, and the Growth SpurtSlide 4HormonesHormonesWhat Triggers Puberty?Secular Trend- The Timing of PubertyPubertal Timing effects: BoysPubertal Timing effects: BoysPubertal timing: GirlsAdolescent Body ImageBrain DevelopmentBrain DevelopmentSlide 15Sleep NeedsAdolescent Use of TimeEating Disorders: Anorexia NervosaEating Disorders: Bulimia NervosaTreatment of Anorexia and BulimiaDrug Use and AbuseAdolescents Differ from Adults in Substances Most AbusedSlide 23Direct Consequences of Alcohol UseSexual BehaviorFactors Associated with Early SexSexually Transmitted Infections Sex EducationTeenage Pregnancy TrendsTraits of Teen MothersTeenage MothersChildren of Teenage MothersMotor Performance in AdulthoodExerciseAlcohol Abuse in Early AdulthoodSexual Activity in Emerging AdulthoodHeterosexual Attitudes and BehaviorReproductive CapacityInfertilityDevelopment and Puberty•Adolescence • the passage from childhood to adulthood•Puberty•Process that leads to sexual maturity or fertility•period of rapid physical maturation involving hormonal and bodily changes• not a single, sudden event19-2Physical Changes•Sexual maturation, height, and weight •Marked weight and height gains•Muscular growth•Facial and chest hair growth in males•Pubic hair growth•Breast growth in females•Lower voice for both males and females•Menarche: girl’s first menstruationWeight, Height, and the Growth Spurt•Gender differences in early adolescence•Girls tend to outweigh boys•Girls tend to be as tall as or taller than boys•Girls start maturation about 2 years earlier•Growth spurt: a rapid increase in height and weight •Typically lasts about 2 years•Results in common “gawkiness”•Teens become more concerned about their appearance3Growth Spurt begins 2 years earlier for girls.Girls gain approximately 3 ½ inches.Boys gain approximately 4 inches4Hormones•Endocrine system’s role in puberty involves interaction: •Hypothalamus•Monitors eating and sex•Pituitary gland •Controls growth and regulates other glands•Gonads: the testes in males, the ovaries in females5Hormones•Increases in certain hormones•Testosterone (higher in males)•development of genitals, increased height, and a change in voice•Estradiol (higher in females)•breast, uterine, and skeletal development•Testosterone and estradiol are present in the hormonal makeup of both boys and girls6What Triggers Puberty?•Leptin•a protein produced by fat cells, may be the most important signal•Rising levels of leptin •signal hypothalamus to stop inhibiting puberty and to set puberty in motion•Thyroid and adrenal glands secrete hormones which leads to somatic changes•Adrenarche: maturation of adrenal glands7Secular Trend- The Timing of Puberty•A decrease in average of pubertal onset•Possible explanations:•Higher standard of living/better nutrition•Overweight (% body fat for hormones)•Relationship with father (Pheromones)8Pubertal Timing effects: Boys•Early Maturation (normal 12yrs, early 10 yrs)•Positives•More popular•better self-esteem•more likely to be leaders•more satisfied with body•Negatives•more likely to get involved in antisocial or deviant activities•truancy•problems at school9Pubertal Timing effects: Boys•Late maturation (about 14 yrs)•Negatives: •More childish•less popular•less likely to hold leadership positions•Positives•show more exploratory behavior, curiosity, social initiative 10Pubertal timing: Girls•Early maturation (before 10 yrs) is a disadvantage •Weigh more and are shorter after puberty ends•May be less well-prepared for puberty•Poorer self-image, more body dissatisfaction, higher rates of depression, anxiety, and eating disorders•Problem behaviors•More likely to engage in deviant behavior (drug and alcohol use, delinquency) •More likely to engage in earlier sexual intercourse and cohabitation11Adolescent Body Image•Preoccupation is strong throughout adolescence•More dissatisfied with bodies during early adolescence• Girls are more dissatisfied and have poorer body image12Brain Development•Adolescent’s brains undergo significant structural changes •corpus callosum •thickens and this improves ability to process information • prefrontal cortex•doesn’t finish maturing until 18 to 25 years of age or later• amygdala•the seat of emotions •matures earlier than the prefrontal cortex•Fully mature during adolescence (around 15)13Brain Development14Images of Brain Development in Healthy Children and Teens (Ages 5-20) 15Mature brain regions in blueSleep Needs•Delayed sleep preference: •Adolescents go to bed later and sleep in later•Average sleep declines to less than 8 hours at age 16•Most adolescents do not get enough sleep16Adolescent Use of Time•US teens have a great deal of discretionary time.•Time with family members declines dramatically•More time is spent alone and with opposite sex•Weekend partying is common for older teens•African-American teens spend more time with family than white teens17Eating Disorders: Anorexia Nervosa•Self-starvation•Distorted body image•May cause irregularity or cessation of menstruation•Often good students and ‘perfectionists’18Eating Disorders: Bulimia Nervosa•Binging and undoing of caloric intake on regular basis•‘Undo’ calories by:•Self-induced vomiting•Excessive exercise•Laxatives, enemas, diuretics•Dieting or fasting19Treatment of Anorexia and Bulimia•Immediate goal is to get patient to eat and gain weight•Patients may be hospitalized if severely malnourished•Behavior therapy•Cognitive therapy 20Drug Use and Abuse•Substance Use•Harmful use of alcohol or other drugs•Dependence or Addiction•Can be psychological•Think you cant go on without the drug•Or Physiological•Actual physical need for drug•Especially dangerous for adolescents because of changing brain structures21Adolescents Differ from Adults in Substances Most Abused 22Adolescents Drink Less Frequently Than Adults, But Drink More Per Occasion23U.S. Substance Abuse and Mental Health Services Administration. 2004 National Survey on Drug Use and Health (NSDUH)Direct Consequences of Alcohol Use•5,000 deaths among youth under 21 per year•Physical and sexual assaults; unwanted/unintended sexual activity•Altered academic/vocational trajectories•Possible adverse effects on