CHAPTER 9 Physical & Cognitive Development in Adolescence

Physical Maturational Changes Signs of Puberty Puberty is the end of childhood & the beginning of adolescence seen in physical and sexual growth Physical Growth: Gains for both boys & girls Girls begin generally 2 years earlier than boys Growth spurt where bones become longer & denser Muscle growth in boys & girls more pronounced growth in boys body fat increase Increases more rapidly in girls heart & lung capacity increases more in boys

Signs of Puberty

Puberty is the end of childhood & the beginning of adolescence seen in physical and sexual growth

Physical Growth:

Gains for both boys & girls

Girls begin generally 2 years earlier than boys

Growth spurt where bones become longer & denser

Muscle growth in boys & girls

more pronounced growth in boys

body fat increase

Increases more rapidly in girls

heart & lung capacity increases more in boys

Sexual Maturation Primary Sexual Characteristics Organs directly involved in sexual reproduction Secondary Sexual Characteristics Physical signs of maturity not directly linked to the reproductive organs Changes in primary & secondary sexual characteristics occur in a predictable sequence for boys & girls For girls, puberty begins w/growth of the breasts & a growth spurt, followed by pubic hair Menarch – the onset of menstruation typically occurs about 13 For boys, puberty usually starts w/growth of the testes & scrotum followed by pubic hair, a growth spurt, & growth of the penis Spermarche – 1st spontaneous ejaculation of sperm-laden fluid typically occurs about age 13

Primary Sexual Characteristics

Organs directly involved in sexual reproduction

Secondary Sexual Characteristics

Physical signs of maturity not directly linked to the reproductive organs

Changes in primary & secondary sexual characteristics occur in a predictable sequence for boys & girls

For girls, puberty begins w/growth of the breasts & a growth spurt, followed by pubic hair

Menarch – the onset of menstruation typically occurs about 13

For boys, puberty usually starts w/growth of the testes & scrotum followed by pubic hair, a growth spurt, & growth of the penis

Spermarche – 1st spontaneous ejaculation of sperm-laden fluid typically occurs about age 13

Mechanisms of Maturation Hypothalamus sends hormones to the pituitary gland triggering release of growth hormones Timing of puberty’s events regulated, in part, by genetics Genetic forces greatly influenced by environmental factors Nutrition & health Puberty occurs earlier in those well-nourished & healthy Social environment also influences puberty’s onset for girls Menarche occurs in younger girls due to family conflict Psychological Impact of Puberty Body image: Adolescents more concerned about overall appearance Girls worry more about & more dissatisfied with their appearance Boys concerned about appearance in early adolescence & become more pleased as changes occur

Hypothalamus sends hormones to the pituitary gland triggering release of growth hormones

Timing of puberty’s events regulated, in part, by genetics

Genetic forces greatly influenced by environmental factors

Nutrition & health

Puberty occurs earlier in those well-nourished & healthy

Social environment also influences puberty’s onset for girls

Menarche occurs in younger girls due to family conflict

Psychological Impact of Puberty

Body image:

Adolescents more concerned about overall appearance

Girls worry more about & more dissatisfied with their appearance

Boys concerned about appearance in early adolescence & become more pleased as changes occur

Response to Menarche & Spermarche Menarche is private occasion in industrialized countries Celebrated with traditions in older cultures Presentation Rites and Rites of Passage Reaction to spermarche less known because of previous knowledge of boys Rate of maturation Early & late maturation: Early maturing boys perceived as more mature & may be more willing to take adult-like responsibilities Late maturing boys often treated like little boys instead of young men Early maturing girls tend to be encouraged to engage in age-appropriate activities such as drinking, smoking, & sex

Menarche is private occasion in industrialized countries

Celebrated with traditions in older cultures

Presentation Rites and Rites of Passage

Reaction to spermarche less known because of previous knowledge of boys

Rate of maturation

Early & late maturation:

Early maturing boys perceived as more mature & may be more willing to take adult-like responsibilities

Late maturing boys often treated like little boys instead of young men

Early maturing girls tend to be encouraged to engage in age-appropriate activities such as drinking, smoking, & sex

Sexual Relations Masturbation Sexual self-stimulation By age 15, 80% of boys & 20% of girls report masturbating Can still produce guilt feelings Now viewed as normal & harmless Sexual Intercourse About 50% of adolescents begin intercourse between 15 & 18 years 10% are postponing sex Double-standard Permissible for males, not for females For many girls, it is okay with affection

Masturbation

Sexual self-stimulation

By age 15, 80% of boys & 20% of girls report masturbating

Can still produce guilt feelings

Now viewed as normal & harmless

Sexual Intercourse

About 50% of adolescents begin intercourse between 15 & 18 years

10% are postponing sex

Double-standard

Permissible for males, not for females

For many girls, it is okay with affection

Pregnancy Statistics Teen pregnancies have dropped 30% in the last 10 years 43 of 1000 births is a teen Pledges in sex classes are useless Teen pregnancies in the U.S. are still 2 – 10 X higher than most other industrialized countries Caring for the child generally goes to the mother with little or no help from the father

Statistics

Teen pregnancies have dropped 30% in the last 10 years

43 of 1000 births is a teen

Pledges in sex classes are useless

Teen pregnancies in the U.S. are still 2 – 10 X higher than most other industrialized countries

Caring for the child generally goes to the mother with little or no help from the father

Sexual Orientation Heterosexuality Sexual attraction & behavior with members of the opposite sex Homosexuality Sexual attraction & behavior with members of the same sex Gay: male homosexuals Lesbian: female homosexuals Bisexuality Sexual attraction & behavior with members of either sex Gender Identity The gender a person believes he or she is psychologically

Heterosexuality

Sexual attraction & behavior with members of the opposite sex

Homosexuality

Sexual attraction & behavior with members of the same sex

Gay: male homosexuals

Lesbian: female homosexuals

Bisexuality

Sexual attraction & behavior with members of either sex

Gender Identity

The gender a person believes he or she is psychologically

Sexually Transmitted Diseases AIDS A leading cause of death among young people Transmitted through body fluids Other STDs 1 in 4 adolescents will contract an STD before graduating high school Chlamydia A bacterial disease Genital herpes Virus-like cold sores or blisters Trichomoniasis Caused by a parasite Gonorrhea & syphilis Oldest known Genital Herpes Syphilis

AIDS

A leading cause of death among young people

Transmitted through body fluids

Other STDs

1 in 4 adolescents will contract an STD before graduating high school

Chlamydia

A bacterial disease

Genital herpes

Virus-like cold sores or blisters

Trichomoniasis

Caused by a parasite

Gonorrhea & syphilis

Oldest known

Health & Nutrition Obesity Body mass index (BMI) Adjusted ratio of weight to height Number of overweight children doubled in past 25 – 30 years Number of overweight adolescents tripled Overweight youngsters unpopular & w/low self-esteem At risk for medical problems Heredity plays a role in juvenile obesity Genes influence obesity by influencing activity level Being genetically prone to inactivity makes it more difficult to burn off calories & easier to gain weight Genes sets up the basal metabolic rate Speed at which the body consumes calories Slower BMR burns off calories more slowly

Obesity

Body mass index (BMI)

Adjusted ratio of weight to height

Number of overweight children doubled in past 25 – 30 years

Number of overweight adolescents tripled

Overweight youngsters unpopular & w/low self-esteem

At risk for medical problems

Heredity plays a role in juvenile obesity

Genes influence obesity by influencing activity level

Being genetically prone to inactivity makes it more difficult to burn off calories & easier to gain weight

Genes sets up the basal metabolic rate

Speed at which the body consumes calories

Slower BMR burns off calories more slowly

Health & Nutrition Environment influences weight Many external cues to eat the wrong foods, ads on the media, encouraging youth to eat tasty but fattening foods Can lose weight with a program that contains: 1. Focus on eating habits & encouragement to become more active 2. Monitoring eating, exercise, & sedentary behaviors Parents help by monitoring their own lifestyle and to set realistic goals & help children reach those goals 3. Eat very little fast food

Environment influences weight

Many external cues to eat the wrong foods, ads on the media, encouraging youth to eat tasty but fattening foods

Can lose weight with a program that contains:

1. Focus on eating habits & encouragement to become more active

2. Monitoring eating, exercise, & sedentary behaviors

Parents help by monitoring their own lifestyle and to set realistic goals & help children reach those goals

3. Eat very little fast food

Threats to Well-being Illegal Drugs 50% of U.S. high school seniors & 20% of 8 th graders used marijuana in the past year Reasons for use Pleasurable experiences Everyday pressures Peer pressures Thrill of doing something illegal Addictive Drugs Drugs producing a biological or psychological dependence leading to cravings Physiological dependence Psychological dependence

Illegal Drugs

50% of U.S. high school seniors & 20% of 8 th graders used marijuana in the past year

Reasons for use

Pleasurable experiences

Everyday pressures

Peer pressures

Thrill of doing something illegal

Addictive Drugs

Drugs producing a biological or psychological dependence leading to cravings

Physiological dependence

Psychological dependence

Legal Drugs Alcohol Binge drinking a “tradition” on college campuses Reasons adolescents start drinking Release inhibitions Reduce tensions & stress Family patterns & genetics play a role Tobacco Nicotine is 4 ½ X more addicting than heroin Produces psychological & physiological addiction Produces a quick dependency Produces pleasant emotional state Seeing parents & peers smoking increases chances of starting

Alcohol

Binge drinking a “tradition” on college campuses

Reasons adolescents start drinking

Release inhibitions

Reduce tensions & stress

Family patterns & genetics play a role

Tobacco

Nicotine is 4 ½ X more addicting than heroin

Produces psychological & physiological addiction

Produces a quick dependency

Produces pleasant emotional state

Seeing parents & peers smoking increases chances of starting

Anorexia & Bulimia Anorexia nervosa Disorder marked by a persistent refusal to eat & an irrational fear of being overweight Have a grossly distorted body image Bulimia nervosa Alternate between binge eating & purging via vomiting or laxatives Commonality in all bulimia is the feeling of not being able to stop eating

Anorexia nervosa

Disorder marked by a persistent refusal to eat & an irrational fear of being overweight

Have a grossly distorted body image

Bulimia nervosa

Alternate between binge eating & purging via vomiting or laxatives

Commonality in all bulimia is the feeling of not being able to stop eating

Piaget Formal Operations Abstract thinking using formal logic Hypotheticodeductive reasoning; Start with a general theory about what produces a particular outcome then deduce explanations for specific situations in which that particular outcome is seen Can begin with abstract possibilities & move to the concrete Propositional thought: Reasoning that uses abstract logic in the absence of concrete examples It’s a gradual unfolding Culture influences the operations

Formal Operations

Abstract thinking using formal logic

Hypotheticodeductive reasoning;

Start with a general theory about what produces a particular outcome then deduce explanations for specific situations in which that particular outcome is seen

Can begin with abstract possibilities & move to the concrete

Propositional thought:

Reasoning that uses abstract logic in the absence of concrete examples

It’s a gradual unfolding

Culture influences the operations

Adolescent Egocentricism Imaginary Audience The adolescent belief that others are as interested in them as they themselves are. The attention-getting behavior is motivated by a desire to be noticed, visible, and “on stage.” Personal Fable The part of adolescent egocentricism that involves their view of their uniqueness and invincibility. It is often seen in the belief that they’ll never suffer horrendous experiences that happen to other people .

Imaginary Audience

The adolescent belief that others are as interested in them as they themselves are. The attention-getting behavior is motivated by a desire to be noticed, visible, and “on stage.”

Personal Fable

The part of adolescent egocentricism that involves their view of their uniqueness and invincibility. It is often seen in the belief that they’ll never suffer horrendous experiences that happen to other people .

Information Processing Information Processing Approach Seeks to identify the way that we take in, use, & store information Metacognition Knowledge that people have about their own thinking processes & their ability to monitor them Decision Making Dating, sex, work or college, friends, etc. Critical Thinking Many even into the 11 th grade still have a self-serving bias in their reasoning

Information Processing Approach

Seeks to identify the way that we take in, use, & store information

Metacognition

Knowledge that people have about their own thinking processes & their ability to monitor them

Decision Making

Dating, sex, work or college, friends, etc.

Critical Thinking

Many even into the 11 th grade still have a self-serving bias in their reasoning

School Performance 78% of U.S. High School Students Graduate SES Scores Middle- & high-SES students score higher grades on standardized tests of achievement & complete more years of education Poverty contributes to lower scores, less years of education, etc.

78% of U.S. High School Students Graduate

SES Scores

Middle- & high-SES students score higher grades on standardized tests of achievement & complete more years of education

Poverty contributes to lower scores, less years of education, etc.

Ethnic/Racial Differences in Performance African American & Hispanic Performance Asian Americans performance higher Difference in part to SES & their view of education Education is less important than getting a job Hard work in school has no payoff Beliefs Regarding Academic Success African Americans more apt to view success as the result of external causes, luck, or social biases They have no control over their success Adolescent beliefs about the consequences of not doing will may also contribute to the differences in school performance

African American & Hispanic Performance

Asian Americans performance higher

Difference in part to SES & their view of education

Education is less important than getting a job

Hard work in school has no payoff

Beliefs Regarding Academic Success

African Americans more apt to view success as the result of external causes, luck, or social biases

They have no control over their success

Adolescent beliefs about the consequences of not doing will may also contribute to the differences in school performance

Dropping Out Statistics ½ million drop out each year Earn 42% less than high school grads Unemployment rate for drop outs is 50% Males drop out more than females Hispanic & African Americans are more likely to drop out Poverty plays a major role in who completes high school

Statistics

½ million drop out each year

Earn 42% less than high school grads

Unemployment rate for drop outs is 50%

Males drop out more than females

Hispanic & African Americans are more likely to drop out

Poverty plays a major role in who completes high school