1. Life-Span Development Twelfth Edition
Chapter 11:
Physical and Cognitive Development
in Adolescence
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2. The Nature of Adolescence
G. Stanley Hall (1904): adolescence is a time of “storm and stress”
More recent research has found that this is not necessarily true
Most adolescents successfully negotiate their path from childhood to adulthood
Negative stereotypes of adolescence are common but are not always accurate
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Puberty
Puberty: a period of rapid physical maturation involving hormonal and bodily changes that occur primarily during early adolescence
Menarche is a girl’s first menstruation
Marked weight and height gains
Growth spurt occurs about 2 years earlier for girls than boys
Girls increase in height 3.5 inches per year, boys about 4 inches
Pubic hair growth
Facial and chest hair growth in males
Breast growth in females
Sexual maturity
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Puberty
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Puberty
Hormonal Changes:
Hormones: chemicals secreted by the endocrine glands and carried throughout the body by the bloodstream
Endocrine system’s role involves the interaction of the hypothalamus, pituitary glands, and gonads
Hypothalamus: brain structure involved with eating and sex
Pituitary gland: endocrine gland that controls growth and regulates other glands
Gonads: testes in males, ovaries in females
Concentration of testosterone and estrogen increases
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Puberty
Hormonal Changes (continued):
Hormones may contribute to psychological development in adolescence
Behavior and moods can affect hormones
Stress, eating patterns, exercise, sexual activity, tension, and depression
Link between hormones and behavior is complex
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Puberty
Timing and Variations:
Average age of menarche has declined significantly
Improved nutrition and health
For boys, pubertal sequence typically begins from age 10–13 ½ and ends from 13–17
For girls, menarche typically begins between the ages of 9 and 15
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Puberty
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Puberty
Preoccupation with body image is especially strong in early adolescence
Girls are generally less happy with their bodies than boys and become more dissatisfied over time
Boys typically become more satisfied as they move through puberty
Research on Body Image in Adolescence:
Appearance
Physical and mental health problems
Best and worst aspects of being a boy or a girl
Body art is becoming more popular among adolescents
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Puberty
Early and Late Maturation:
Boys:
Early-maturing boys view themselves more positively and have more successful peer relations
Late maturing boys report a stronger sense of identity in their 30s
In general, early maturation seems to be better
Girls:
Early-maturing girls are more likely to smoke, drink, be depressed, have an eating disorder, struggle for earlier independence, have older friends, date earlier and have earlier sexual experiences
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Puberty
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The Brain
The adolescent brain undergoes significant structural changes
Corpus callosum thickens; improves adolescents’ ability to process information
Amygdala (handles processing of information about emotion) develops earlier than the prefrontal cortex (involved in higher-level cognitive processes)
Adolescents are driven by strong emotions but have difficulty controlling these passions
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The Brain
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Adolescent Sexuality
Adolescent sexuality is a time of exploration, experimentation, sexual fantasies, and incorporating sexuality into one’s identity
Every society gives some attention to adolescent sexuality
In the U.S., sexual culture is widely available to adolescents
Television and other media contribute to the sexual culture
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Adolescent Sexuality
Developing a Sexual Identity Involves:
Learning to manage sexual feelings
Developing new forms of intimacy
Learning skills to regulate sexual behavior
Sexual Identity Includes:
Activities
Interests
Styles of behavior
Indication of sexual orientation
Gay male and lesbian youth have diverse patterns of initial attraction, often have bisexual attractions, and may have physical or emotional attraction to same-sex individuals
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Adolescent Sexuality
Timing of sexual initiation varies by country, gender, and other socioeconomic characteristics
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; Asian American adolescents are the least sexually active
Early sexual activity is linked with risky behaviors (drug use, delinquency, school-related problems)
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Adolescent Sexuality
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Adolescent Sexuality
Low parental monitoring is linked with early initiation of sexual activity, more sexual partners, and less condom use
Dramatic increase in oral sex during adolescence
Considered a casual, recreational activity by many
Belief that oral sex is not really sex
Belief that it is likely to be safer than sexual intercourse
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Adolescent Sexuality
Adolescents are increasing their use of contraceptives
Some still use contraceptives inconsistently
Sexually transmitted infections (STIs) are contracted primarily through sexual contact
U.S. has one of the highest adolescent pregnancy rates in the industrialized world
Difference exists despite the fact that U.S. adolescents are no more sexually active
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Adolescent Sexuality
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Adolescent Sexuality
Adolescent pregnancy creates health risks for baby and mother
Low birth weight, neurological problems, childhood illness
Mothers often drop out of school and typically do not catch up economically
It is often not pregnancy alone that leads to negative consequences
Adolescent moms are more likely to come from low-SES backgrounds
Many were not good students before they became pregnant
Some adolescent mothers have positive outcomes
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Adolescent Health
Many factors related to poor health habits and early death in adulthood begin during adolescence:
Poor nutrition
Lack of exercise
Inadequate sleep
Adolescents typically need about 9 hours of sleep
Adolescents’ biological clocks shift as they get older
Conflicts with school starting times
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Adolescent Health
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Adolescent Health
Leading Causes of Death in Adolescence:
Accidents
Typically motor vehicle accidents
A large percentage are due to alcohol or drug impairment
Homicide
More common among African American males
Suicide
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25. Substance Use and Abuse
United States has one of the highest rates of adolescent drug use of any industrialized nation
Adolescent alcohol and cigarette consumption has declined in recent years
Use of painkillers (Vicodin, Oxycontin) is increasing
Parents, peers, and social support can play important roles in preventing adolescent drug abuse
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26. Substance Use and Abuse
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Eating Disorders
Research Findings:
Body Image:
Adolescents are dissatisfied with their bodies
Low self-esteem and social support, weight-related teasing, and pressure to lose weight
Parenting:
Healthy eating patterns and exercise by parents increased adolescents’ healthy habits
Sexual Activity:
Sexually active girls were most likely to be dieting
Role Models and the Media:
Girls who were motivated to consume media with thin, female images were more likely to report dissatisfaction with their bodies
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Eating Disorders
Anorexia Nervosa: an eating disorder that involves the relentless pursuit of thinness through starvation
Three Main Characteristics:
Weighing less than 85% of what is considered normal for a person’s age and height
Having an intense fear of gaining weight that does not decrease with weight loss
Having a distorted image of their body shape
Typically begins in the early to middle teen years, often following an episode of dieting
10 times more likely to occur in females than males
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Eating Disorders
Anorexia Nervosa (continued):
Most anorexics are White females from well- educated, middle- to upper-income families, and are competitive and high achieving
Linked to problems in family functioning
Fashion image in the U.S. contributes to the incidence of anorexia
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Eating Disorders
Bulimia Nervosa: eating disorder in which the individual consistently follows a binge-and- purge pattern
Most bulimics:
Are preoccupied with food
Have an intense fear of becoming overweight
Are depressed or anxious
Have a distorted body image
Bulimics typically fall within a normal weight range
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Adolescent Cognition
Piaget’s Formal Operational Stage (age 11+):
More abstract than concrete operational thought
Increased verbal problem-solving ability
Increased tendency to think about thought itself
Thoughts of idealism and possibilities
More logical thought
Hypothetical-deductive reasoning: involves creating a hypothesis and deducing its implications
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Adolescent Cognition
Evaluating Piaget’s Theory:
Much more individual variation than Piaget envisioned
Education in science and math promotes the development of formal operational thinking
Cognitive development is likely not as stage-like as Piaget thought
Children can be trained to reason at a higher stage; some cognitive abilities emerge earlier than Piaget thought
Piaget developed the notion of children as active, constructive thinkers and developed many concepts that are still used today
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33. Adolescent Egocentrism
Heightened self-consciousness of adolescents
Imaginary Audience: adolescents’ belief that others are as interested in them as they themselves are
Personal Fable: involves a sense of uniqueness and invincibility
Invincibility attitudes are associated with reckless behavior
Drug use
Suicide
Having unprotected sex
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34. Information Processing
Improvement in executive functioning
Reasoning, making decisions, monitoring thinking critically, monitoring one’s cognitive process
Individuals become more competent decision- makers with age
Most people make better decisions when calm
Unfortunately, adolescents have a tendency to be emotionally intense
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35. Information Processing
Cognitive changes that improve critical thinking skills include:
Increased speed, automaticity, and capacity of information-processing
More breadth of content knowledge in a variety of domains
Increased ability to construct new combinations of knowledge
A greater range and more spontaneous use of strategies or procedures for applying or obtaining knowledge
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Schools
Transition to Middle or Junior High School:
Takes place at a time when many changes (individual, family, and school) are occurring at once
Puberty and concerns about body image
Emergence of formal operational thought
Increased responsibility; decreased dependence on parents
Change to a larger, more impersonal school structure
Change from one teacher to many teachers
Change to a larger, more heterogeneous set of peers
Increased focus on achievement and performance
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Schools
Top-Dog Phenomenon: moving from being the oldest, biggest, and most powerful students in elementary school to being the youngest, smallest, and least powerful students in middle or junior high school
Positive Aspects of Transition:
More likely to feel grown up
More subjects from which to select
More opportunities to spend time with peers
Increased independence from direct parental monitoring
Challenged intellectually by academic work
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Schools
Effective Schools for Young Adolescents:
Develop smaller communities that lessen impersonality of middle schools
Lower student–counselor ratios to 10-to-1
Involve parents and community leaders
Develop new curricula
Integrate several disciplines in a flexible curriculum
Have more student health and fitness programs
Help students who need public health care
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High School
Expectations for success and standards for learning are often too low
Many students graduate with inadequate reading, writing, and mathematical skills
Many go on to college and must enroll in remediation classes there
Students who drop out often do not have skills that allow them to obtain decent jobs or be informed citizens
Dropout rates have declined over last 50 years
Dropout rates are highest among minorities
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High School
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High School
Most Effective Programs:
Provide early reading programs, tutoring, counseling, and mentoring
Emphasize the creation of caring environments and relationships
Use block scheduling
Offer community-service opportunities
Service Learning: a form of education that promotes social responsibility and service to the community
More effective when:
Students have a choice in activities
Students are given opportunities to reflect on participation
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High School
Benefits of Service Learning:
Higher grades in school
Increased goal-setting
Higher self-esteem
Improved sense of being able to make a difference for others
Increased likelihood that they will serve as volunteers in the future
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