Chapter 12: Physical and Cognitive Development in Adolescence

Transcription

1 Chapter 12: Physical and Cognitive Development in Adolescence McGraw-Hill 2006 by The McGraw-Hill Companies, Inc. All rights reserved.

2 The Nature of Adolescence

3 What physical changes occur in adolescence? Pubertal with rapid physical changes involving hormones Menarche is a girl s first menstruation Puberty is also triggered by body mass Genetic factors are involved in puberty Puberty involves the interaction of the hypothalamus, pituitary gland, and gonads The onset of puberty varies among individuals

4 Median Ages at Menarche in Selected Northern European Countries and the United States from 1845 to 1969 Norway Finland Sweden U.K. U.S.A. Median age (years) at menarche Fig Year 1980

5 Most noticeable physical changes include Pubic hair growth Facial and chest hair growth in males Breast growth in females Increased height and weight Sexual maturity Adolescent sexuality is initiated by First ejaculation, voice change, penis elongation, and testes development in males Highly irregular menstrual cycles, rounding of breasts, and widening of hips in females

6 Hormone Levels by Sex and Pubertal Stage for Testosterone and Estradiol Testosterone (pg/ml) Estradiol (pg/ml) Boys Girls Pubertal stage Fig. 12.2

7 Early onset of puberty can create risks for females Depression Eating disorders Use of alcohol, drugs, and/or tobacco Earlier dating and sexual involvement with males Possible lower educational attainment Pubertal changes have a strong effect on the adolescent s body image, dating interest, and sexual behavior

8 Males Females Onset (average) Completion (average) Normal Range and Average Development of Sexual Characteristics in Males and Females Fig Age (years) Height spurt Penile growth Menarche Testicular growth Breast growth Growth of pubic hair

9 Adolescent sexuality is a time of exploration, experimentation, and sexual fantasies Adolescence is a bridge between the asexual child and sexual adulthood reaction of each society may vary Television and other media contribute to the sexual culture Developing a sexual identity involves Sexual behavior Indication of sexual orientation

10 Early- and Late-Maturing Adolescent Girls Perceptions of Body Image in Early and Late Adolescence Early development Late development Body Image Score +.10 Mean Grade 6 Grade 10 Fig. 12.5

11 Percentages of sexually active young adolescents in the United States vary greatly Male, African American, and inner-city adolescents report being the most sexually active Early sexual activity is linked to other risky behaviors and to contracting STIs Self-regulation and parent child relationships are two important factors in sexual risk-taking Adolescents are increasing their use of contraceptives Cross-culturally, the United States still has one of the highest adolescent pregnancy and birth rates

12 Cross-Cultural Comparisons of Adolescent Pregnancy Rates U.S. England and Wales Canada France Sweden 20 0 Fig Year

13 What happens to the adolescent brain? Spurts occur in the brain s electrical activity that may signal changes in cognitive development Some of the most recent discoveries regarding areas of the brain involved emotions and information-processing

14 Adolescent Problems and Health

15 What can be said about substance use and abuse among adolescents? 1960s and 1970s were a time of marked increases in the use of illicit drugs and social unrest Annual studies since 1975 show that adolescent drug use among U.S. secondary school students Declined in the 1980s Began to increase in the 1990s Declined among high school seniors after 1998 Explanations for declining rates vary Parents and peers can influence usage attitudes

16 60 Trends in Drug Use by U.S. Eighth-, Tenth-, and Twelfth-Grade Students 40 12th grade 10th grade 20 8th grade Percentage of students who reported illicit drug use in past 12 months Year Fig. 12.8

17 Young Adolescents Reports of Use in the Family Matters Program 90 Figs and Control group Experimental group Percentage Reporting Use in their Lifetime of: Alcohol Cigarette smoking Baseline 3 mos 1 yr Baseline 3 mos 1 yr Initial reporting and 1st & 2nd follow-up

18 Families are important when adolescent substance abuse and negative consequences are evident Eating problems and disorders are increasingly common in adolescence most notably, anorexia nervosa and bulimia nervosa Since the 1960s, a higher percentage of adolescents have become overweight Most anorexics are White adolescents or young adult females from well-educated, middleand upper-income families Stress results from not achieving high expectations Weight becomes something they can control

19 The Increase in Being Overweight in Adolescence from 1968 to 1999 in the United States Percentage overweight adolescents, years of age Year Fig

20 Adolescent health is of great importance Many factors linked to poor health habits and early death in adulthood begin in adolescence Cross-culturally, U.S. adolescents exercised less and ate more junk food Early formation of healthy behavior patterns has Immediate benefits Prevents or delays major causes of premature disability or death

21 Nutrition, exercise, and adolescent sleep patterns have physiological and psychological effects At home During school In social interactions Leading causes of adolescent death Accidents most are motor vehicle related Homicide second leading cause of death Suicide rate has tripled since 1950s

22 Adolescent Cognition

23 Adolescent cognition shows greater abstract quality in ability to Solve problems by verbal means alone Create make-believe or purely hypothetical situations Engage in extended speculation and test solutions systematically Assimilation dominates development of thought In later adolescence, accommodation returns to thinking and information-processing

24 Adolescent egocentrism involves two types of social thinking: imaginary audience and personal fable Adolescents have a sense of uniqueness and invincibility Invincibility attitudes are likely to be associated with reckless behavior such as Drug use Suicide Having unprotected sex

25 Adolescence is a time of increased decision-making Situations are examined from multiple perspectives, and consequences anticipated A strategy for improving adolescent decisionmaking includes parental involvement Cognitive changes that improve critical thinking include Increased speed of information-processing Wider range of knowledge in variety of domains Increased ability to construct new knowledge Having more strategies to apply knowledge

26 Schools

27 The transition from elementary to middle or junior high school is of interest because It can be stressful It occurs at a time when family child relationships change Puberty and concerns about body image accompany changes in social cognition A more impersonal school structure is entered There is increased responsibility and independence The top-dog phenomenon is experienced Creating effective and positive environments for student learning is needed

28 Recommendations for effective schools include Develop smaller communities that lessen impersonality of middle schools Lower student counselor ratios to 10-to-1 Involve parents and community leaders Develop curricula that produce better students Integrate several disciplines in a flexible curriculum Have more student health and fitness programs

29 U.S. high school education is of concern because of these facts: Some students graduate with inadequate skills Unskilled students go into college remedial classes Dropouts lack adequate workplace skills Dropout rates have declined over last 50 years Dropout rates are highest among minorities Students drop out of school for many reasons

30 Trends in High School Dropout Rates Latino African American Total White Percentage of 16- to 24-year-olds who have dropped out of school Fig

31 High schools for the future need to promote More awareness of knowledge and skills needed by students upon graduation Higher expectations for student achievement Strong, positive adult role models Higher-quality work experiences More coordination and communication among all grade levels More student service learning experiences

32 The End