Infancy: Physical Development

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CHAPTER 14
Adolescence:
Physical Development
Learning Outcomes
LO1 Describe the changes of puberty and its
effects on adolescents.
LO2 Discuss emerging sexuality and the risks of
sexually transmitted infections among
adolescents.
LO3 Discuss adolescent health, including
causes of death and nutritional issues.
LO4 Discuss substance abuse and dependence
among adolescents.
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TRUTH OR FICTION?
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T-F American adolescents are growing taller
than their parents.
T-F Girls are fertile immediately after their
first menstrual period.
T-F Most adolescents in the U.S. are
unaware of the risks of HIV/AIDS.
T-F You can never be too rich or too thin.
T-F Some college women control their
weight by going on cycles of binge eating
followed by self-induced vomiting.
T-F Substance abuse is on the rise among
high school students.
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Introduction and Historical Views of
Adolescence
• Adolescence Defined
• Except for infancy, more changes occur during
adolescence than any other time of life.
• Adolescence is a transitional period between childhood
and adulthood.
– The capacity for abstract thought emerges.
– Search for personal identity and direction for one’s life
are explored.
– The concept of adolescence as a distinct stage of life is
relatively new within the past century, induced by
increasingly more complex cultural and societal changes.
• Legal definitions are varied.
– You are considered “adult” at different ages depending
on the situation:
• Enlisting in the armed services; buying alcohol; driving a
car; voting; or getting married
Introduction and Historical Views of
Adolescence
• Historical Views
– Early 1900s
• Hall (early American Psychologist) viewed adolescence as
a time of Sturm und Drang (German term for storm and
stress).
• He saw teenage as a time of turmoil and fluctuation
between different aspects of life.
• He thought mood swings and conflicts with parents were
essential to making the transition to adulthood.
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Introduction and Historical Views of
Adolescence
• Historical Views, cont.
– Mid-Century
• The Freudian Concepts
– Sigmund Freud viewed adolescence as the Genital
Stage of psychosexual development.
– After initial attraction toward same sex parent, this stage
heralds the transference of that attraction to other adults
or peers.
– Anna Freud (Sigmunds’ daughter) viewed adolescence
as a turbulent period resulting from increased sex drive.
– Characterized by unpredictable behavior, defiance of
parents, confusion, and mood swings
– Contemporary Theorists
• No longer see it as a time of inevitable stress and upheaval
• But merely as a time of biological, cognitive, social, and
emotional reorganization
LO1 Puberty: The Biological
Eruption
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Puberty: The Biological Eruption
• Puberty
– A stage of development characterized by reaching
sexual maturity and the ability to reproduce
– It is controlled by physical processes of the glands and
hormone production:
– Hypothalamus: triggers the pituitary gland to…
– Pituitary gland: release hormones that control
growth and functioning of gonads…
– Gonads: respond by increasing production of
androgens and estrogens (sex hormones) that in turn
stimulate the hypothalamus, thus creating a feedback
loop
Puberty: The Biological Eruption
• Puberty, cont.
– Hormones also trigger development of:
• Primary sex characteristics = reproductive organs
– Girls: ovaries, vagina, uterus, fallopian tubes
– Boys: penis, testes, prostate gland, seminal vesicles
• Secondary sex characteristics = physical indicators
of sexual maturation
– Girls: breast development
– Boys: deepening of the voice and facial hair
– Both sexes: pubic and underarm hair
Puberty: The Biological Eruption
• The Adolescent Growth Spurt
– Teen awkwardness is a result of Asynchronous
Growth (different parts of body growing at different
rates).
• Hands and feet mature before arms and legs (an
exception to the principle of proximodistal growth).
• Legs reach peak growth before shoulders and chest (a
reversal of cephalocaudal growth).
• Early spurt growth may result in shorter legs and longer
torsos.
• Later spurt growth results in longer legs.
• But there are no significant differences in height at
maturity regardless of early or late growth spurts.
• A tall child can reasonably be expected to be a tall adult
and a short child a short adult.
Puberty: The Biological Eruption
• The Adolescent Growth Spurt, cont.
– Height:
• Girls:
– Start to spurt earlier than
boys (about age 10), reaching
peak growth rate at about
age 12
– Average about 3 inches per
year, adding around 13
inches to height overall
© Adrian Bischoff /Photolibrary
Puberty: The Biological Eruption
• The Adolescent Growth Spurt, cont.
– Height:
• Boys:
– Start to spurt about age 12, reaching peak growth
rate at about age 14
– They grow more during the spurt than girls, averaging
about 4 inches per year, adding on average 14.5
inches to height overall
Figure 14.1 – Spurts in Growth
Puberty: The Biological Eruption
• The Adolescent Growth Spurt, cont.
– Weight:
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Weight spurt begins about 6 months after height spurt.
Peak growth in weight occurs about 1.5 yrs after onset.
Spurt continues in both boys and girls for about 2 yrs.
Girls are taller and heavier than boys from about 9-10 to
13-14 yrs because their growth spurt starts earlier.
Once boys begin to spurt however, they catch up with and
surpass the girls becoming both taller and heavier.
Because weight spurt is after the height spurt, many
teens are relatively slender compared to pre-teen and
post-teen years.
Growing requires enormous quantities of food.
Active 14-15 yr old boys consume 3,000-4,000 calories a
day to maintain growth; later in life that would add about
100 lbs a year
Figure 14.2 – Growth Curves for Height and
Weight
Puberty: The Biological Eruption
• The Adolescent Growth Spurt, cont.
– Girls’ and boys’ body shapes begin to differ in
adolescence.
• Girls:
– Hips grow broader than shoulders.
– Girls become overall more “rounded” in shape due to
almost twice the gain in fatty tissue than boys.
– Estrogen typically brakes the female growth spurt
some years before testosterone brakes that of males.
– Girls low in estrogen during late teens may grow
taller; most reach adult height due to genetic
variations
• Boys:
– Shoulders grow broader than hips.
– And gain twice as much muscle tissue as girls
Puberty: The Biological Eruption
• The Secular Trend
– Over the past century, children in the Western world
have typically grown taller than children in previous
generations and experienced an earlier onset of
puberty.
– Although middle and upper-income children no longer
continue that trend, children from lower-class families
still make gains in height from generation to generation.
– Perhaps the taller and heavier higher SES children
have better nutritional advantages and have reached
the optimal genetic growth range for humans.
– Continued gains in growth in lower SES may reflect that
they are still benefiting from improvements in nutrition.
Figure 14.3 – Are We Still Growing Taller than
Our Parents?
Puberty: The Biological Eruption
• Pubertal Changes in Boys
– First signs:
• Pituitary gland signals increase in testosterone
• Accelerating growth of testes: average age 11.5 yrs
– Later developments:
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Penis growth spurt begins about a year later
Followed by growth of pubic hair
Underarm hair begins growth around age 15
Facial hair begins as upper lip fuzz; full beard growth
follows in another 2-3 years
• Beard and chest hair continue to develop past age 20.
• Testosterone levels remain fairly stable in boys although
they decline gradually into adulthood.
Puberty: The Biological Eruption
• Pubertal Changes in Boys, cont.
– Other events:
• Around 14-15 yrs the voice deepens due to growth of
larynx; development is gradual and causes voice to
“crack”
• Testosterone triggers acne, affecting 75-90% of teens;
boys are more prone and have more severe outbreaks.
• Males are capable of erections in early infancy but
spontaneous erections are not frequent until age 13-14.
• Organs producing semen (fluid containing sperm) grow
rapidly; first ejaculation of seminal fluid is around 13-14,
about 1.5 yrs after penis growth spurt
Puberty: The Biological Eruption
• Pubertal Changes in Boys, cont.
– Other events:
• Nocturnal emissions (a.k.a. wet dreams) begin around a
year after semen production; mature sperm are found
around age 15
• It is a myth that nocturnal emissions coincide with erotic
dreaming.
• About half of all boys experience gynecomastia (the
enlargement of breast tissue in males) but typically
declines in a couple of years; the grow is generated by
small amounts of female sex hormones secreted by the
testes; if accelerated and problematic, it can be treated
with drugs (tamoxifen) or surgery
• At age 20-21, epiphyseal closure (changing cartilage
into bone in long bone structures) causes boys to stop
growing taller, and puberty for boys draws to a close
• Pubertal Changes in Girls
– Overall signs:
• Pituitary gland signals ovaries
to increase estrogen.
• Estrogen stimulates growth of
breast tissue; “breast buds” may develop as early as 8-9
yrs but usually begin to enlarge around age 10.
• Breasts typically reach full growth by 3 years, but
mammary glands (produce and secrete milk) do not
mature until a woman gives birth.
• Estrogen causes hip and buttock tissue to grow; coupled
with widening of pelvis creates roundness of hips.
• Around age 11 adrenal glands also produce small
amounts of androgens (male hormones) that stimulate
growth of pubic and underarm hair; if excessive can
cause dark or increased facial hair.
• Estrogen causes labia, vagina, and uterus to develop.
• Androgens cause the clitoris to develop.
© Roy McMahon/Getty Images
Puberty: The Biological Eruption
Puberty: The Biological Eruption
• Pubertal Changes in Girls, cont.
– Menarche: (first menstruation)
• Occurs on average between ages 11-14 (plus or minus 2
years)
• Fat cells secrete the protein leptin, signaling the brain to
increase estrogen levels.
• Menarche comes later to girls with less body fat.
• In mid 1800s, European girls first menstruation was about
age 16.
• By 1960s, the average age for American girls dropped to
12.5 years.
• But onset of puberty has leveled off for both girls and
boys in recent years.
Figure 14.4 – The Decline in Age at Menarche
Puberty: The Biological Eruption
• Pubertal Changes in Girls, cont.
– Hormonal Regulation of the Menstrual Cycle:
• Estrogen and progesterone levels vary markedly and
regulate the menstrual cycle.
• When estrogen reaches peak blood levels, a ripe ovum is
released by the ovary, usually around 12-18 months after
menarche
• The lining of the uterus thickens in preparation to support
an embryo.
• If fertilization does not take place, menstruation follows by
sloughing off the lining (endometrium).
• Estrogen levels then increase and growth of the
endometrium begins again.
• The average cycle is 28 days; individual variations are
common
• The first few years after menarche, cycles are often
irregular but patterns tend to develop later.
Puberty: The Biological Eruption
• Early versus Late Maturers
– Boys:
• Early maturers tend to be more popular and more likely to be
leaders.
• They are more poised, relaxed, and good-natured.
• They have an edge in athletics and heightened sense of
self-worth.
© Ellen Senisi/The Image Works
Puberty: The Biological Eruption
• Early versus Late Maturers, cont.
– Boys:
• But on the negative side, early maturers have greater risk for
delinquency, aggression, and substance abuse.
• They may experience earlier demands for sexual
opportunities they are not emotionally ready to respond to.
• Late maturers may feel more dominated by earlier maturers.
• But may have the “advantage” of not being rushed into
maturity
• Benefits of early maturation is greatest among lower SES
teens who often place more value on physical prowess.
• Middle and upper-income teens are more likely to value
academic achievements available to late-maturing boys.
Puberty: The Biological Eruption
• Early versus Late Maturers, cont.
– Girls:
• Opposite of early maturing boys, early maturing girls may
feel awkward, conspicuous, and self-conscious about the
physical changes that begin in puberty.
• Boys may tease about developing breasts and being
taller; and shorter boys are reluctant to approach or be
seen with them.
• Overall early maturing girls are at greater risk for
psychological problems and substance abuse.
• Many early maturers have lower grades and initiate
sexual activity earlier.
• Parent may be more restrictive with early maturers
leading to child/parent conflicts.
Puberty: The Biological Eruption
• Body Image
– Adolescents are very concerned about their physical
appearance, especially in the early teen years when
changes are occurring so rapidly.
– By age 18, they tend to become more satisfied with
their bodies.
– Teenage girls in our culture are more preoccupied with
being thin than are boys.
• Majority of girls are likely to diet and more likely to suffer
from eating disorders.
– Teenage boys typically strive to put on more weight and
build muscle mass.
LO2 Emerging Sexuality and
Risks of Sexually Transmitted
Infections
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Emerging Sexuality and Risks of
Sexually Transmitted Infections
• Transmitted Infections
– Sexually active teens have higher rates of STIs than any
other age group.
– 1 in 6 American teens contracts an STI every year.
– Most commonly occurring STIs in teens:
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Chlamydia
Gonorrhea
Genital warts
Genital herpes
Syphilis
HIV/Aids
Emerging Sexuality and Risks of
Sexually Transmitted Infections
• Common STIs
– Chlamydia
• The most common STI in teens and college students
• A bacterial infection of the vagina or urinary tract
• Major cause of pelvic inflammatory disease (PID) which
can lead to sterility
– Human Papilloma Virus (HPV)
• Causes genital warts and is associated with cervical
cancer
• Warts may appear on visible areas but most are on cervix
in women or on urethra in men and not visible.
• More than 50% of sexually active teenage girls are
infected with HPV.
• Sexual intercourse before age 18 and having many sex
partners increases susceptibility to infection.
• There is a vaccine for prevention, which is best
administered prior to becoming sexually active.
Emerging Sexuality and Risks of
Sexually Transmitted Infections
• HIV/AIDS
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HIV: Human immunodeficiency virus
AIDS: Acquired immunodeficiency syndrome
HIV is the virus that causes AIDS.
By 2000, nearly 39 million people worldwide were
infected.
– 1,100,000 people in the U.S. now have it.
– Women account for minority of cases in U.S., but
worldwide sexually active teenage girls have higher
rates of HIV than older women or young men.
Emerging Sexuality and Risks of
Sexually Transmitted Infections
• HIV/AIDS, con’t.
– Anal intercourse (often practiced by gay men) and
injecting drugs with shared needles are routes of
transmission.
– But it is erroneous to believe this is a disease of gays
and drug users only.
– The primary mode of transmission worldwide is malefemale intercourse; half of U.S. women are infected this
way.
– Nearly all high school students are aware that HIV/AIDS
is transmitted sexually but about half do not change their
sexual practices as a result; they often deny the threat
to themselves.
Emerging Sexuality and Risks of
Sexually Transmitted Infections
• Risk Factors for STIs
– Factor 1:
• Sexual activity: dramatically increases between ages 1518
• By age 15: one in four teens have engaged in sexual
intercourse
• By age 18: two in three are sexually active
– Factor 2:
• Sex with multiple partners
• 15% of high school students report sex with 4 or more
partners
Emerging Sexuality and Risks of
Sexually Transmitted Infections
• Risk Factors for STIs, cont.
– Factor 3:
• Failure to use condoms
• Only 62% reported using condoms the last time they had
sexual intercourse.
– Factor 4:
• Drug abuse
• Teens who abuse drugs are more likely to engage in the
other risky behaviors.
Table 14.3 – Overview of Sexually Transmitted
Infections (STIs)
Table 14.3 – Overview of Sexually Transmitted
Infections (STIs) cont.
Emerging Sexuality and Risks of
Sexually Transmitted Infections
• Prevention of STIs
– Education about transmission, symptoms, and
consequences of STIs is the essential key to prevention.
– Use of condoms lowers levels of infections.
– But knowledge alone may not change behavior due to
peer pressure.
LO3 Health in Adolescence
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Health in Adolescence
• Most teens are healthy and growing.
• Injuries tend to heal quickly.
• About 18% of U.S. teens experience at least one
serious health problem.
© Giovanni Rinaldi/iStockphoto.com
Health in Adolescence
• Risk Taking in Adolescence
– Teenagers are more likely to engage in risky behaviors
than younger children.
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Excessive drinking
Substance abuse
Reckless driving
Violence
Disordered eating behavior and unprotected sexual
activity
Health in Adolescence
• Risk Taking in Adolescence
– Causes of Death:
• Death rates are low in adolescence.
– But higher for for older teens; twice as many 15-17 yr
olds as 12-14 yr olds die
– Male teens are twice as likely to die than females, due
to higher risk taking behaviors
– 65% of teen deaths in U.S. are result of injuries
– 60% are due to accidents, most involving motor
vehicles
– Alcohol is also implicated in drowning and falling.
Health in Adolescence
• Risk Taking in Adolescence, cont.
– Causes of Death:
• Highest at risk are poor, urban teens
• Homicide rates for African American male teens (age 1519) are nearly 10 times higher than European male teens.
• African American teenage girls (age 15-19) are 5 times
more likely to be victims of homicide than European
American girls.
• Figures for Latino/a American teens fall somewhere
between those two.
Figure 14.5 – Injury Death Rates among Adolescents Ages 15–
19 by Sex, Ethnicity, and Type of Injury
Health in Adolescence
• Nutrition: An Abundance of Food
– The average teenage girl requires 1,800-2,000 calories
a day to fuel growth.
– The average teenage boy requires 2,200-3,200 calories
a day to fuel growth.
– They both use twice as much calcium, iron, zinc,
magnesium, and nitrogen at the peak of the growth
spurt than at any other time.
– Calcium is more important for girls to help prevent
osteoporosis (a progression of bone loss) later in life.
– Teens are less likely to get Vitamin A, thiamine, and
iron.
– And more likely to get more fat, sugar, protein, and
sodium than recommended
Health in Adolescence
• Nutrition: An Abundance of Food, cont.
– Reasons for deficits in nutrition:
• Breakfast is often skipped, especially by girls who dieting.
• Teens are more likely to miss meals or eat away from
home.
• Consumption of large amounts “junk” and “fast” food
• Junk food is high in calories but low in nutrition and is
connected with overweight problems even into adulthood
that lead to chronic illness and earlier death.
• Overweight teens are more likely to suffer from heart
disease, strokes, and cancer as adults; this holds true
even for teens who later lose the weight.
Health in Adolescence
• An Abundance of Eating Disorders
– Our cultural emphasis on being thin coupled with the
unique psychology of teens (especially girls) leads to a
high vulnerability for eating disorders.
– The wealthier one’s family is, the more unhappy a teen
is with their body.
– Girls of “average” weight are dissatisfied and want to
meet the newer slimmer images.
– It is no wonder dieting has become a normal way of
eating for teenage girls.
Health in Adolescence
• An Abundance of Eating Disorders, con’t.
– Anorexia Nervosa:
• A life-threatening eating disorder characterized by extreme
fear of being too heavy, dramatic weight loss, a distorted
body image, and resistance to eating enough to reach or
maintain a healthy weight
• Denial of any health problems is common.
• More teen girls diet than not, but anorexia is an extreme
form of controlling weight.
• Teens with this disorder weigh less than 85% of their
normal weight.
• Primarily seen in girls but also to a lesser degree in males
(most studies put it at a 10 to 1 ratio)
Health in Adolescence
• An Abundance of Eating Disorders, con’t.
– Anorexia Nervosa:
• Typically afflicted are European American females from
higher SES families.
• Incidences of eating disorders have risen sharply in recent
years.
• Girls can drop more than 25% of their weight in a year.
• Abnormalities in the endocrine system (hormones)
develop that prevent ovulation.
• There is risk for premature osteoporosis.
• Problems arise with the respiratory and cardiovascular
systems and overall health declines as nearly every bodily
system is affected.
• The mortality rate for anorexic females in 4-5%.
Health in Adolescence
• An Abundance of Eating Disorders, con’t.
– Bulimia Nervosa:
• A sort of “companion” disorder to anorexia
• It is symptomized by recurrent cycles of binge eating and
purging.
• It often follows periods of dieting.
• Purging usually refers to forced vomiting but can include:
fasting, laxatives, and extreme exercise
• Similar to anorexia, it strikes primarily teen girls with a
tendency to be perfectionists about their bodies.
Health in Adolescence
• An Abundance of Eating Disorders, con’t.
– Perspectives on Eating Disorders:
• Psychoanalytic Views:
– Anorexia may symbolize sexual fears especially pregnancy.
– May prevent separating from family unit and assuming adult
role in life
– May be in rebellion to strict parents that forced eating habits
– Or in response to parents criticisms of their weight
– Many girls with eating disorders are victims of abuse,
particularly sexual abuse.
– Media role models project an extreme ideal of slenderness.
» In 1920, Miss America had a Body Mass Index (BMI) of
20-25, considered normal by the World Health
Organization (WHO) numbers below 18.5 rate as
malnourished
» Current Miss Americas have BMI’s as low as 17
» Over the past 20 years, the “ideal” has lost 12 lbs and
only gain 2 inches in height.
Health in Adolescence
• An Abundance of Eating Disorders, con’t.
– Perspectives on Eating Disorders:
• Genetic Implications:
– Eating disorders tend to run in families.
– Genetic factors may include obsessionistic and
perfectionistic personality traits.
Health in Adolescence
• An Abundance of Eating Disorders, con’t.
– Treatment and Prevention:
• Eating disorders can be life-threatening and some teen
girls are admitted to hospital care against their will.
• Many deny having a problem.
• Refusal or inability to eat normally may be circumvented
by use of feeding tubes.
• Antidepressants such as Prozac and Zoloft that increase
serotonin in the brain are used frequently in treating eating
disorders with some success.
• Cognitive-behavioral therapy assists in redefining body
images and reinforcing appropriate eating habits.
• Overall, prevention will have to address cultural values as
well as individual problems.
LO4 Substance Abuse and
Dependence
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Substance Abuse and Dependence
• Substance Abuse
– The ongoing use of a substance despite the social,
occupational, psychological, or physical problems it
causes.
– The “amount” is not the issue, the “role” it plays in one’s
life is the issue.
• Substance Dependence
– Is a more serious issue
– Someone who is dependant on a substance loses
control and may organize their
life around getting the substance
and using it.
© Jan Tadeusz/Alamy
Substance Abuse and Dependence
• Bodily changes due to dependence
– Tolerance:
• Develops as the body becomes used to the substance,
therefore progressively higher doses are needed to
achieve the same effects.
– Abstinence Syndrome:
• When substances are physically addictive and the user
stops taking the drug or lowers the dosage, they will
experience withdrawal symptoms.
• Many who begin using substances for pleasure end up
using them just to avoid painful withdrawal symptoms.
Substance Abuse and Dependence
• Effects of drugs
– Depressants:
• Alcohol:
– Is a depressant, even though small amounts appear to
stimulate
– It lessens inhibitions; drinkers do things they normally may
not do
– Ingesting 5 or more drinks in a row is binge drinking, and is
connected to bad grades and risky behavior including
unprotected, promiscuous sex, aggressiveness, and
accidents.
– Alcohol is also an intoxicant; it distorts perceptions, impairs
concentration, hinders coordination, and slurs speech.
– Hundreds of student die each year from alcohol-related
accidents and from overdoses; yes, a person can die from
drinking too much at one time.
– Chronic heavy drinking is linked to cardiovascular disorders,
cirrhosis or cancer of the liver, and breast cancer.
Substance Abuse and Dependence
• Effects of drugs
– Depressants:
• Heroin:
– Is derived from the opium poppy
– Its major medical use is pain relief.
– It provides a euphoric “rush,” prompting repeated use.
– It is addictive.
• Barbiturates:
– Have various legitimate medical uses, such as relief
from pain, anxiety, and tension.
– Used to treat insomnia, hypertension, and epilepsy
– Users become rapidly dependent
– Teens use because of the mild euphoric effect.
– Mixing barbiturates with other depressants is very
dangerous due to additive effects.
Substance Abuse and Dependence
• Effects of drugs
– Stimulants: speed up heartbeat and other body
functions
• Nicotine:
– Is found in cigars, cigarettes, and chewing tobacco
– Causes release of adrenaline, speeds up the heart, disrupts
it’s rhythm, and causes the liver to pour sugar into the blood
– Raises rate the body burns calories and lowers appetite,
leading some to use it as a means of weight control
– It is addictive; withdrawals symptoms include drowsiness,
irregular heartbeat, sweating, tremors, dizziness, insomnia,
headaches, and digestive problems.
– Nearly 450,000 Americans die every year from smokingrelated problems.
– Cigarette smoke contains carbon monoxide, causing
shortness of breath and hydrocarbons (tars) responsible for
most respiratory diseases and lung cancer.
Substance Abuse and Dependence
• Effects of drugs
– Stimulants:
• Cocaine:
– Produces feelings of euphoria, relieves pain, boosts selfconfidence, and reduces appetite
– Accelerates heart rate, spikes blood pressure, constricts
arteries, and thickens blood; can cause cardiovascular and
respiratory collapse
– May be used to boost athletic performance and confidence
– Overdoes can cause restlessness, insomnia, and tremors.
• Amphetamines:
– Widely known for enabling staying awake and reducing
appetite; high doses cause restlessness, insomnia, and
irritability.
– Tolerance develops rapidly.
– Regular use of methamphetamine may be physically
addictive.
Substance Abuse and Dependence
• Effects of drugs
– Hallucinogenics: (cause perceptual distortions)
• Marijuana:
– Derived from the Cannabis sativa plant
– Typically smoked but can be eaten
– Users report feelings of relaxation and elevation in mood;
greater sensory awareness; self-insight; creativity; an
empathy for others
– Smokers become highly aware of accelerated heartbeat,
experience visual hallucinations, and the sensation that time
is slowing down
– Strong intoxication can disorient and frighten some users.
– It impairs perceptual-motor coordination needed in driving.
– Slows learning and impairs short-term memory
– Users can become psychologically dependent and some
experience withdrawal which is a sign of physical
dependence.
Substance Abuse and Dependence
• Effects of drugs
– Hallucinogenics, cont.
• Ecstasy:
– a.k.a. MDMA is a popular “party or club drug”
– Chemically similar to amphetamines and mescaline, it gives
users the boost of stimulants, increases feelings of elation
and self-confidence, and removes them from “reality.”
– Reduces inhibitions and cognitive awareness increasing risky
behaviors
– Can also impair working memory; increase anxiety and lead
to depression
• LSD: (acronym for lysergic acid diethylamide)
– Can cause psychological dependence and tolerance but not
physically addictive
– High doses impair coordination and judgment.
– Causes mood swings and paranoid delusions
Substance Abuse and Dependence
• Prevalence of Substance Abuse
– Comparing self-reported substance abuse of 8th, 10th,
12th graders in 1991 to 2008 shows:
• Use of alcohol, cigarettes, and marijuana was relatively
high
• Some drugs have been used by fewer than 10% of
students: MDMA, cocaine, LSD, steroids, and heroin
• Only 1/5 of 8th graders now report ever using cigarettes.
• Less than 2% of high school students report using steroids.
Table 14.4 – Trends in Lifetime Use of Various Substances for Eighth-,
Tenth-, and Twelfth-Graders, 1991 versus 2008 (Percents)
Substance Abuse and Dependence
• Student’s Attitudes toward Drugs
– Research tracking high school students’ disapproval of
drug use from 1978 to 2008 shows:
• Students of both eras are more likely to disapprove of
regular drug use more than occasional experimentation
with drugs.
• In 1978, 33.4% disapproved of experimental marijuana use
and in 2008, 55.5% disapproved.
• But disapproval for regular use rose to 67.5% in 1978 and
79.6% in 2008.
• Only a minority of seniors disapproved of trying alcohol:
15.6% in 1978 and 29.8% in 2008.
• But most seniors disapprove of regular drinking in both
eras.
• Overall, disapproval ratings are somewhat higher in 2008
than 1978.
Table 14.5 – Disapproval of Drug Use by TwelfthGraders, 1978 versus 2008
Substance Abuse and Dependence
• Factors in Substance Abuse and Dependence
– Adolescents become involved with drugs for several
reasons:
•
•
•
•
Conformity to peer pressure
Rebellion against moral and social constraints
Escape from boredom or school pressure
Some are imitating their parents abuse of drugs
– Heavy drug use is most likely to occur in families with
permissive or neglecting-rejecting parenting styles.
– Teen drug users usually do poorly in school.
– Psychological characteristics include anxiety and
depression, antisocial behavior, and low self-esteem.
– Children may inherit genetic predispositions toward
abuse of specific drugs.
• For instance: children of alcoholics are more likely to abuse
alcohol.
Substance Abuse and Dependence
• Treatment and Prevention
– There are many approaches to prevention and treatment
of substance abuse and dependence among
adolescents.
– But it is not clear which approaches are most effective.
– Part of the problem in therapy is the teens’ lack of desire
to quit using their drug/s of choice.
– Peer pressure may reinforce the continuation of use.
– Eliminating the physical dependence is attainable but the
social and psychological aspects are not as
straightforward to deal with.
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