Transcript Adolescence: Physical Development

The Developing Person Through Childhood and Adolescence
by Kathleen Stassen Berger
Seventh Edition
Chapter 14
Adolescence:
Biosocial Development
Slides prepared by Kate Byerwalter, Ph.D.,
Grand Rapids Community College
Question: What is “Adolescence”?

What age period do you think of when
you hear the word “adolescence”? Decide
when you think it begins and ends.

What words or images come to your mind
when you hear the word “teenager”?
Make a list.
Berger: The Developing Person Through Childhood and Adolescence, 7th Edition, Chapter 14
Adolescence

Adolescence refers to the age period
between childhood and adulthood.

TWEENS: 10-13 years
 TEENS: 13-18 years
 EMERGING ADULTHOOD: 18-25 yrs
Berger: The Developing Person Through Childhood and Adolescence, 7th Edition, Chapter 14
Puberty Begins

Puberty is a period of rapid physical growth
and sexual maturation.

The sequence of physical changes is
universal, but the timing varies (typically
lasting 3-5 years).

Age of onset ranges between 8-15 years.
Berger: The Developing Person Through Childhood and Adolescence, 7th Edition, Chapter 14
Berger: The Developing Person Through Childhood and Adolescence, 7th Edition, Chapter 14
Puberty Begins (cont.)

Menarche: the term for a girl’s first period.
It signals that ovulation has begun
(although is often irregular for a few years)

Spermarche: the term for a boy’s first
ejaculation, which signals sperm
production has begun
Berger: The Developing Person Through Childhood and Adolescence, 7th Edition, Chapter 14
Hormones

Puberty begins with a signal from the
hypothalamus–to the pituitary gland–to
adrenal glands (the HPA axis) and gonads.

Gonads release testosterone and
estradiol.

Hormones influence MOOD and THOUGHT.
Berger: The Developing Person Through Childhood and Adolescence, 7th Edition, Chapter 14
Biological Sequence of Puberty
Berger: The Developing Person Through Childhood and Adolescence, 7th Edition, Chapter 14
Sexual Maturation

Primary sex characteristics:
 The
parts of the body directly involved in
reproduction (e.g., testicles, ovaries)

Secondary sex characteristics:
 Not
necessary for reproduction
 Examples: odor, acne, breast development,
hair, voice changes
Berger: The Developing Person Through Childhood and Adolescence, 7th Edition, Chapter 14
Sudden Emotions

Hormones contribute to the conflict,
moodiness, and sexual urges of
adolescents, but are not the only cause.

Social and cultural reactions to visible
body changes also play a large roll.
Berger: The Developing Person Through Childhood and Adolescence, 7th Edition, Chapter 14
Make it Real: Sudden Emotions

Can you recall a time being especially
embarrassed or angry during adolescence?
Berger: The Developing Person Through Childhood and Adolescence, 7th Edition, Chapter 14
Timing of Puberty
JEFF GREENBERG / PHOTOEDIT, INC.
Berger: The Developing Person Through Childhood and Adolescence, 7th Edition, Chapter 14
Timing of Puberty

Age of onset of puberty depends on:
 GENDER
 GENES
(girls ahead by months or years)
and ETHNICITY
 WEIGHT
(malnutrition delays puberty)
 STRESS
(causes puberty earlier)
Berger: The Developing Person Through Childhood and Adolescence, 7th Edition, Chapter 14
Quiz: Timing of Puberty

For adolescent girls,
do you think it is
advantageous to be
“early maturing”?

What about for boys?
PHOTODISC
Berger: The Developing Person Through Childhood and Adolescence, 7th Edition, Chapter 14
Early Maturation: Correlations

Early maturing girls
are at higher risk of:

Early maturing boys
are at higher risk of:
 Teasing
 Rebellion
 Early
 Breaking
sexual activity
 Eating disorders
 Early substance use
the law
 Stress and depression
from relationships
Berger: The Developing Person Through Childhood and Adolescence, 7th Edition, Chapter 14
Late Maturation: Correlations

Late maturation may also be difficult,
especially for boys in a school in which
athletics is valued.

Late maturing girls may feel anxiety about
when puberty will hit. (Anyone remember “Are
You There God, It’s Me, Margaret” by Judy
Blume?)
Berger: The Developing Person Through Childhood and Adolescence, 7th Edition, Chapter 14
Bigger and Stronger

The growth spurt is a sudden and rapid
period of physical growth during puberty.

Sequence is weight, height, muscles.

Females gain more fat, males gain muscle.

The lungs and heart increase in size.
Berger: The Developing Person Through Childhood and Adolescence, 7th Edition, Chapter 14
Other Physical Changes

The lymphoid system (tonsils, adenoids)
decrease in size. This makes teens less
susceptible to asthma and colds.

Skin gets oilier, sweatier, more acne-prone.
Berger: The Developing Person Through Childhood and Adolescence, 7th Edition, Chapter 14
Body Rhythms

Most teenagers’ bodies prefer to stay up
late and sleep in late.

Teens also tend to get too little sleep for
their growing bodies.
 Lack
of sleep has been associated with higher
risk of mood disorders and driving problems.
Berger: The Developing Person Through Childhood and Adolescence, 7th Edition, Chapter 14
Make it Real: School Schedules

A few high schools have experimented
with later start (and end) times for the
school day, with positive results. Would
you have liked this idea? What problems
might it have created for you?

(Be sure to read your text (p. 442) to find
out what the positive results were!)
Berger: The Developing Person Through Childhood and Adolescence, 7th Edition, Chapter 14
Make it Real: The Teen Brain

Think of an example of an emotional
reaction or impulsive behavior that you
have witnessed an adolescent make.

Do you have any explanation WHY the
person reacted as they did?
Berger: The Developing Person Through Childhood and Adolescence, 7th Edition, Chapter 14
Brain Development in
Adolescence

Research has found that the limbic
system, an emotional and impulsive part
of the brain, develops prior to the
prefrontal cortex, the rational, logical part
of the brain.

This in part explains some of the
impulsive, emotional reactions of teens.
Berger: The Developing Person Through Childhood and Adolescence, 7th Edition, Chapter 14
Neural Connections

Myelination of the prefrontal cortex
improves with age, fostering
improvements in decision making, rational
arguments, and even reaction time.

Experiences during adolescence are
particularly crucial and lasting.
Berger: The Developing Person Through Childhood and Adolescence, 7th Edition, Chapter 14
Make it Real:
Healthy or Unhealthy?

In general, would
you describe
adolescence as a
relatively HEALTHY,
or UNHEALTHY time
of life?
RUBBERBALL PRODUCTIONS
Berger: The Developing Person Through Childhood and Adolescence, 7th Edition, Chapter 14
Health During Adolescence

In general, adolescence is a HEALTHY
age period.
 Problem-free
reproduction
 Peak athletic performance
 High energy and endurance
 Body systems function at an optimal level
 Death by disease is rare (worldwide!)
Berger: The Developing Person Through Childhood and Adolescence, 7th Edition, Chapter 14
Health During Adolescence

Unfortunately, teens seem to engage in
behaviors that put their health at risk.

The incidence of eating disorders has
also increased, especially among females.

Fatal accidents, suicides, and
homicides are the leading cause of death,
especially for males.
Berger: The Developing Person Through Childhood and Adolescence, 7th Edition, Chapter 14
A Twisted Memorial
DOMINIC CHAVEZ / THE DENVER POST / AP PHOTO
Berger: The Developing Person Through Childhood and Adolescence, 7th Edition, Chapter 14
Injury and Death

Accidental deaths during adolescence are
likely due to:
 Body
changes (e.g., testosterone)
 Brain
changes (e.g., the limbic system)
 Social
context (e.g., alienation, “macho”)
Berger: The Developing Person Through Childhood and Adolescence, 7th Edition, Chapter 14
Question: Sexual Actions
Take a guess: How many teens do you
think have had sexual intercourse by age
14? Age 17?
RUBBERBALL PRODUCTIONS

Berger: The Developing Person Through Childhood and Adolescence, 7th Edition, Chapter 14
Sexual Actions

In the U.S.:
 About
25% of teens have had sexual
intercourse by age 14
 About 50% by age 17
 About 90% by age 21

Culture influences how sexually active
a teen may be.
Berger: The Developing Person Through Childhood and Adolescence, 7th Edition, Chapter 14
Pregnancy in Adolescence

Psychological effects withstanding, the
physical toll of pregnancy during
adolescence (especially age 15 or
younger) is problematic.

Pregnancy may interfere with hormones,
height, and nutrition, and the girl’s uterus
may be not yet be mature.
Berger: The Developing Person Through Childhood and Adolescence, 7th Edition, Chapter 14
Sexually Transmitted Infection

Worldwide, 50% of teens will be have an
STI (STD) during adolescence.
 Examples:

HIV, syphilis, chlamydia, herpes
STI’s can cause later infertility. The risk of
serious consequences and reinfection are
higher for teens than adults.
Berger: The Developing Person Through Childhood and Adolescence, 7th Edition, Chapter 14
Make it Real: Drug Use

What was the
atmosphere
regarding drug
use at your
high school, or
in your
neighborhood?
STUART FRANKLIN / MAGNUM PHOTOS
Berger: The Developing Person Through Childhood and Adolescence, 7th Edition, Chapter 14
Drug Use

The “Monitoring the Future” study has
found that most U.S. teens use alcohol
and tobacco before age 18, and about
50% have tried marijuana.

The U.S. has the greatest number of
available drugs, although the majority of
teens don’t use them.
Berger: The Developing Person Through Childhood and Adolescence, 7th Edition, Chapter 14
“Monitoring the Future” Study
Berger: The Developing Person Through Childhood and Adolescence, 7th Edition, Chapter 14
Question: Drug Use, WHY?

What are
some possible
reasons an
adolescent
might use
drugs?
LAUREN GREENFIELD
Berger: The Developing Person Through Childhood and Adolescence, 7th Edition, Chapter 14
Drug use: Why?

Adolescents use drugs for various
reasons, including:
 The
desire to fit in with peers
 The thrill of the sensation
 As a way to self-medicate
 A perception that it is a “normal” part of
being a teenager
Berger: The Developing Person Through Childhood and Adolescence, 7th Edition, Chapter 14
Drug Use: Long-Term Effects

Some teens move beyond use to abuse
(use causing harm) or addiction (physical
and psychological need).

The younger a person tries a drug, the
more likely addiction will occur (especially
for cigarettes).
Berger: The Developing Person Through Childhood and Adolescence, 7th Edition, Chapter 14
Drug Use: More Long-Term
Effects

Certain drugs may:
 Cause
cancer
 Increase the risk of death by car accident
 Interfere with healthy eating and absorption
of nutrients (especially tobacco)
 Reduce fertility (especially tobacco)
 Interfere with brain development
(especially alcohol)
Berger: The Developing Person Through Childhood and Adolescence, 7th Edition, Chapter 14
Prevention of Drug Use

Prevention efforts such as D.A.R.E. have
been found to have no impact on
adolescent drug use.

However, increased prices and
enforcement of laws have helped reduce
cigarette use, specifically.
Berger: The Developing Person Through Childhood and Adolescence, 7th Edition, Chapter 14
Nutrition During Adolescence

Teens’ lack of iron increases the risk of
anemia, and impairs muscle development.

Teens’ lack of calcium increases the risk
of osteoporosis later in life.

Vending machines in schools contribute
to poor eating habits among teenagers.
Berger: The Developing Person Through Childhood and Adolescence, 7th Edition, Chapter 14
Obesity During Adolescence

About 12% of teenagers are overweight
(BMI greater than 25), a higher percentage
than in earlier decades.

Lifestyle choices seem to play a large role
in this (e.g., lack of exercise, too much TV).

Fast food and soda pop also play a role.
Berger: The Developing Person Through Childhood and Adolescence, 7th Edition, Chapter 14
Body Image

Adolescents report that their body
image is the most
important predictor
of their self-esteem.

Unfortunately, this
can lead to eating
disorders.
PHOTODISC
Berger: The Developing Person Through Childhood and Adolescence, 7th Edition, Chapter 14
Anorexia Nervosa

Anorexia involves self starvation.

It is a refusal to maintain at least 85% of a
normal Body Mass Index (BMI).

It includes disturbed body perception and
denial.

It leads to a number of physical problems,
including lack of menstruation (females),
and perhaps even death.
Berger: The Developing Person Through Childhood and Adolescence, 7th Edition, Chapter 14
Bulimia Nervosa

Bulimia involves repeatedly overeating
and then purging via laxatives or vomiting.

Diagnosis requires 1 episode a week for at
least 3 months, an uncontrollable urge to
overeat, and distorted body image.

Bulimia can cause damage to the
gastrointestinal system or death.
Berger: The Developing Person Through Childhood and Adolescence, 7th Edition, Chapter 14
Treatment for Eating Disorders

If you are worried about someone with a
possible eating disorder:
 Get
online and EDUCATE YOURSELF about
the symptoms and the best ways to help
 TALK
to the person in a calm, non-judgmental
manner. Don’t keep quiet.
Berger: The Developing Person Through Childhood and Adolescence, 7th Edition, Chapter 14