Chapter 11 The Nature of Adolescence Many negative stereotypes of adolescence Today s adolescents aren t provided with adequate opportunities and support to become competent adults They are a heterogeneous group o Different portraits emerge depending on type of adolescent described Physical Changes Puberty a period of rapid physical maturation occurring primarily in early adolescence that involves hormonal and bodily changes Male pubertal characteristics include in this order increase in penis testicle size appearance of straight pubic hair minor voice change first ejaculation masturbation or wet dream appearance of kinky pubic hair onset of maximum growth in height and weight growth of hair in armpits more detectable voice changes and facial hair growth Menarche a girl s first menstruation o Growth spurt occurs two years earlier for girls o Age 9 peak is 11 5 for girls and age 11 peak is 13 5 for boys Hormonal Changes o Hormones powerful chemical substances secreted by the endocrine glands and carried through the body by the o o bloodstream Testosterone for boys Estradiol for girls type of estrogen but they are both present in each sex Stress eating patterns exercise sexual activity tension and depression can activate or suppress the hormonal system o Hormone behavior link is complex Timing and Variations in Puberty o Maturity age has decreased over the years o Nutrition health and other environmental factors affect puberty s timing and makeup o Boys 10 13 may end between 13 17 o Girls 9 15 o U S girls beginning at age 8 9 o African American girls developing earlier than non Latino White girls Precocious Puberty o Describes very early onset and rapid progression of puberty o When puberty happens before age 8 for girls 9 for boys o More common in girls Preoccupation with body image is strong throughout adolescence Body Image o o More dissatisfied with their bodies during early adolescence o Girls are less happy with their bodies more negative images than boys have they become more satisfied because muscle mass Early and Late Maturation o Berkeley Longitudinal Study early maturing boys perceived themselves more positively and had more successful peer relations than did late maturing counterparts o Late maturing boys had a stronger sense of identity at age 30 may have occurred because they had more time to explore life s options For girls late maturation has been linked with body image o ADVANTAGEOUS to be an early maturing boy o o Early maturing girls show greater satisfaction with figures in sixth grade o By tenth grade late maturing girls are more satisfied o Late maturing girls have bodies more closely approximate the current American ideal of feminine beauty o Studies show early maturation increases girls vulnerability to a number of problems Smoking drinking be depressed eating disorder struggle for earlier independence from parents older friends Early dating and sexual experiences The Brain o Changes occur in brain during adolescence o Thickening of the corpus callosum and a gap in maturation between the amygdala and the prefrontal cortex which functions in the reasoning and self regulation o Amygdala the seat of emotions such as anger matures earlier than the prefrontal cortex o There are connections between development the brain and socioemotional processes Adolescence Sexuality o Sexual intercourse in early adolescence is associated with negative developmental outcomes o Contraceptives used by adolescences is increasing o One in four sexually experienced adolescent acquires a sexually transmitted infection o U S adolescent pregnancy rate is high but has been decreasing in recent years o Pregnancy creates high health risks for baby and mother Likely to have low birth rate Neurological problems and childhood illness Issues in Adolescent Health Adolescent Health o Adolescence is a critical juncture in health because many factors related to poor health habits and early death in the adult years begin during adolescence Poor nutrition lack of exercise inadequate sleep are concerns o o Three leading causes of death in adolescence are accidents homicide and suicide Substance Use and Abuse o Lloyd Johnston monitored the drug use of America s high school seniors in a wide range of public and private high schools at the Institute of Social Research at University of Michigan Surveyed drug use by 8th and 10th graders in 1991 o o United States has one of the highest rates of adolescent drug use of any industrialized nation o Major adolescent problem although its rate has been dropping as has cigarette smoking o Recent concern in prescription pain killers o Parents peers social support and educational success play an important role in whether they take drugs o Eating disorders have increased in adolescents with a substantial increase in the percentage who are overweight o Anorexia Nervosa an eating disorder that involves the relentless pursuit of thinness through starvation o Bulimia Nervosa an eating disorder in which the individual consistently follows a binge and purge pattern Only considered severe if occurs twice a week or three times a month o Anorexia starts in early and middle adolescent years Eating Disorders Adolescent Cognition Piaget s Theory Around age 7 children enter the concrete operational stage of cognitive development o They can reason logically about concrete events and objects and can start to classify objects o At age 11 the fourth and final stage of cognitive development the formal operational stage begins The Formal Operational Stage o This stage is more abstract than concrete operational thought o Adolescents can conjure up make believe situations abstract propositions and events that are purely hypothetical and can try to reason logically about them o Hypothetical deductive reasoning Piaget s formal operational concept that adolescents have the cognitive ability to develop hypothesis or best guesses about ways to solve problems such as an algebraic equation Evaluating Piaget s Theory o There is much more individual variation than Piaget envisioned become formal operational thinkers Adolescent Egocentrism the heightened self consciousness of adolescents o David Elkind points out egocentrism has 2 key components Only about 1 in three young adolescents is a formal operational thinker and many American adults never The imaginary audience involves adolescents belief that others are as interested in them as they themselves are Personal fable the part of adolescent