Physical and Cognitive Development in Adolescence
Conceptions of Adolescence
Adolescence- the transition period between childhood and adulthood.
Puberty marks the beginning of adolescence, with a huge change in body
development and concurrent hormonal changes that lead to sexual maturity.
Biological perspective suggests that along with the physical changes due to
puberty, comes heightened emotionality, conflict, and defiance of adults – Hall’s
storm and stress view.
Social perspective says that the problems focused on during adolescence are
exaggerated. Mead believed that teens had problems related to how the culture
treated this changing stage. If the social environment offers clear guidelines in
adjustment to adulthood, children won’t have developmental problems.
Balanced point of view suggests that adolescence is a function of both biological
and social forces. There are natural stresses in learning new roles, taking on more
responsibility, so there will be self-doubt and disappointment. Culture also
determines how long this transition period will be.
Puberty: the physical transition to adulthood falls into two types: 1) overall body
growth and 2) maturation of sexual characteristics.
o Growth hormone (GH) increases to promote bone and muscle growth.
o Thyroxine increases.
o Estrogens are the female hormones, but they are also found in males.
They promote breast development, sex organ development. They also
regulate the menstrual cycle.
o Androgens (testosterone) drive muscle growth, hair growth and mature
male sex characteristics. They drive gains in body size, as well as libido.
o Adrenal androgens released by the adrenals atop the kidneys influence
girls’ height spurt and body hair.
o Growth spurt- the first outward sign of puberty is the rapid gain in height
and weight. Girls begin growing after age 10, boys around age 12 ½.
Girls’ size gains are surpassed by boys when their spurt begins. Growth
for girls is about over by age 16, for boys by age 17 ½.
o Body proportions change as the body reverses the cephalocaudal trend-
the hands, legs, and feet outgrow the torso, then the torso grows. So they
truly are gawky and out of proportion. Sex differences appear. Boys’
shoulder broaden, girls’ hips broaden. Boys end up taller in general,
because they had longer to grow before the growth spurt occurred.
o Muscle-fat makeup – girls add fat from age 8+, especially between 11
and 16. Boys lose fat on arms and legs. Muscle increase is greater in boys,
as well as lung capacity, blood cells and oxygenation, leading to overall
greater muscle strength.
o Changing states of arousal as teens go through sleep “phase delay”. They
go to bed later and have a hard time getting up the in morning. Sleep
declines from 10 hours to 7 or 8 hours/ night. Sleep deprivation
contributes to poor academic performance, depression, behavior problems.
Some schools have compensated by having high school start later than
Motor development and physical activity- gross motor performance improves,
with girls’ gains leveling off around age 14. Boys spurt in strength, speed and
endurance all through the teen years. Boys and girls are no longer well-matched
physically, so gender-segregated PE begins in middle school. Many new sports
are included in the curriculum at this point. Title IX in 1972 mandated equal
opportunities for both genders in sports, etc, so girls are participating more than in
the past. But expectations & rewards are still higher for boys in athletics. Sports
participation is helpful, not just for physical training, but for competition,
assertiveness training, problem solving, and teamwork.
o Primary sexual characteristics are reproductive organs’ development.
o Secondary sexual characteristics are additional signs of sexual maturity-
breast development, bodily hair.
o Sexual maturation in girls –Menarche is first menstruation, around 12+
years. After menarche, secondary characteristics develop over 3 years. For
about a year after menarche, there is no ovulation, leading to a temporary
sterility as the girls’ body matures. This occurs after the growth spurt,
when a girl actually could have a baby.
o Sexual maturation in boys –Spermarche is first ejaculation, after age
13. The first sign of puberty in boys is the enlargement of the testes. The
growth spurt peaks around age 14, when the sex organs are nearly mature.
Facial and body hair develop. As the larynx enlarges and vocal cords
lengthen, boys’ voice changes.
Individual and group differences- Heredity contributes to timing of puberty, as
well as nutrition and exercise. Body fat percentage contributes to girls’ timing of
sexual maturation. Fat cells stimulate the ovaries to produce sex hormones, so
menarche may occur earlier for heavier girls. Girls who are delayed in
development may be very thin or training vigorously. Overall physical health
seems to contribute to development, since teens in poverty suffering malnutrition
may develop much later. African-American girls reach menarche earlier than
White girls. Family security or chaos also contributes- evolution seems to have set
us up to develop earlier if our families are disturbed or at risk- earlier procreation.
o Secular trend is a generational trend in pubertal timing. In wealthier
nations, girls’ age of menarche has declined over the past 100 years.
Psychological impact of pubertal events
Reactions of pubertal changes-Girls experience mixed feelings about the
transition into adulthood- happy to be a woman, but confused about what that will
mean for them, what expectations they must meet, etc. If they have no prior
knowledge, menarche will be disturbing to them. Most girls today are informed,
so it’s not a shock. Girls also tell a friend or parent. Boys also experience
disturbed feelings, even though they usually know what to expect. They also don’t
have the outlet to talk about their experience with others, so they get less social
support to deal with the changes.
o Rite of passage is an initiation ceremony that marks a change in privilege
and responsibility. These celebrations let the teen know that their changes
are valued in their culture. Western teens have many ages of significance-
age for employment, driving, leaving school, voting, drinking. Since
there’s not a consistent time that marks maturity, they seem to be delayed
in fully maturing.
Pubertal change, emotion, and social behavior
o Adolescent moodiness is somewhat related to hormonal fluctuations,
there are other things that also contribute. Negative events linked to
negative moods: problems with parents, discipline, problems at school,
breaking up with a girlfriend, etc. Their moods are more unstable than in
the past. Mood relates to activities, so they generally are happier on the
weekend when with peers.
o Parent-child relationships- there is a rise in conflict with parents as teens
try to establish some autonomy. This is not culturally related, as it occurs
in most cultures. This seems to allow for the separation that is necessary at
this time. First there is psychological distancing, finally physical
separation. Friction increases as teens’ abstract thinking graduates to
wanting to be treated like an adult, instead of a child. Unfortunately, teens
can’t accurately judge risk, so their parents have legitimate concerns and
feel the need to oversee their activities and friends.
Early vs. late maturation is different for boys and girls. Boys’ early maturing is
viewed as a positive, enhancing self-esteem and confidence. Girls’ early maturing
may leave them feeling odd girl out, burdened with responsibility, more anxious
and less confident. Early maturing girls may be more involved in substance abuse,
sexual activity and lower achieving in school. Later maturing girls are seen as
more physically attractive, sociable and school leaders. These perceptions depend
on how closely the teens’ body matches the ideals of attractiveness, and how well
youth fit in physically with peers.
o Role of physical attractiveness – this one aspect determines much of a
teens’ popularity. The ideal is long-legged, tall, thin for girls; tall, broad-
shouldered, muscular for boys.
Body image (attitude toward one’s physical appearance) is more
negative for early maturing girls. Boys develop a more positive
body image if they are early maturing.
o Importance of fitting in with peers- those who find themselves at the
ends of the average ranges have fewer people to connect to with the same
maturing issues. Early maturers tend to hang with older peers, which may
have some negative side-effects, such as early introduction to substances
and sex. If early maturing girls go to a girls’ school, there’s not as much
pressure from peers. Also it helps if girls stay in a K-6 school.
o Long-term consequences are almost the opposite of the initial reactions.
Early maturing girls and later maturing boys tend to be independent,
flexible, achieving and satisfied with life as adults. The other youth tend to
be rigid and dissatisfied as adults. They may not have had to develop the
same coping skills as teens who suffered during adolescence.
Nutritional needs shift during the growth spurt- teens eat a lot more.
Unfortunately, their diets are poorest, as they have more autonomy and don’t eat
with the family as often. Iron deficiency is the most common nutritional problem.
They may also have poor intake of calcium, which they need for growing bones.
Many girls are engaging in fad diets, so their diets are skewed.
Eating disorders erupt at this time as girls are comparing their bodies to peers
and advertisements, setting up disappointment with their looks. Serious eating
disorders begin with a diet which allows the teen a feeling of control.
o Anorexia nervosa is self-starvation due to a fear of getting fat. It is a
more common problem for girls (90% of anorexics are girls), but it’s
found in all SES groups and most cultures, except African-American.
Anorexics have distorted body images, seeing themselves as fat, even
though they have bones sticking out. They may exercise strenuously, as
well. They may lose 25-50% of body weight, even losing their menstrual
cycle and contributing to bone loss, heart deterioration, kidney failure and
brain damage. 6% of anorexics die from the disease. These girls tend to be
perfectionists and don’t believe anything they do is good enough. They
may be high achieving students, but get little satisfaction from that.
Parents tend to be overcontrolling, especially focused on appearance,
emotionally distant. These girls rebellion is internal through unshakable
self-control. Hospitalization may be necessary to save the girls’ lives since
they don’t believe they have a problem. The treatment involves family
o Bulimia nervosa is the binge-purge eating disorder. Dentists often pick up
this disorder first, since vomiting destroys enamel on teeth, and may cause
tears in the esophagus. 2-3% of girls may have this disorder (1% for
anorexics). There is a fear of getting fat, but the families are more
emotionally distant, rather than controlling. For bulimics, food is a
compensation for lack of parental care and nurture. Bulimics know they
have a problem, and they may also engage in substance abuse, or
shoplifting. They are more open to getting help, especially with support
groups, therapy, education, and retraining in body imaging.
Sexual activity increases as teens have more time with peers, and the sex
hormones drive libido to a high level.
o Culture makes a difference in how a teen is talked to about sex, as well as
how much sex a teen is exposed to in the culture. Western culture offers
many images of sex, yet not much clear information about the
consequences of sexual behavior. Most parents still hold restrictive sexual
values for teens, so they don’t talk much or clearly to them about sex.
o Adolescent sexual attitudes and behavior have become more liberal
over the past 30 years. As attitudes liberalize, so does behavior. Males
have sex earlier than girls, but most have sex with only one partner.
o Characteristics of sexually active adolescents- early maturation, parental
divorce, single-parent homes, large families, little religious involvement,
sexually active friends or siblings, poor school achievement, delinquency
and deviant behavior, impoverished background.
o Contraceptive use has increased, but 20% of teens are at risk for
unintended pregnancy. One common reason given is that they weren’t
planning to have sex. There is still a stigma against teen sexuality, which
puts them at higher risk for consequences. 12% of American girls say they
have been forced to have sex. 25% of those having sex, say they didn’t
really want to but felt they had little choice. Teens who have a good
relationship with parents tend to use birth control more responsibly.
o Sexual orientation differs for 3-6% of teens who recognize they are gay
or lesbian. Heredity contributes to homosexuality, as identical twins of
both sexes are more likely than fraternal twins to share a homosexual
orientation. It may be sex-linked, more common to the mother’s blood line
than the father’s. Certain genes affect the impact of prenatal sex
hormones, which modify brain structures that may induce homosexual
behavior and feelings. Female fetuses exposed to higher levels of
androgens in the womb have a greater likelihood of being lesbian. Gay
men are more likely to be later born in a family of boys, indicating the
mother’s body produces antibodies to androgens which reduce the impact
of male sex hormones on the brains of later-born boys. Since some
cultures stigmatize homosexuals, developing a healthy sexual identity is
harder for a homosexual teen. This seems to go through 3 phases:
Feeling different – many homosexuals say they felt different even
as children. Their play interests were more like the opposite
gender, even before sexual drive developed.
Confusion occurs as teens feel sexually different. There is
awareness of same-sex attraction between ages 11 & 12 for boys,
and 14 & 15 for girls. Confusion occurs since they all assumed
they were heterosexual like all their friends. They may struggle
with what that identity means for them, and they have few role
models to observe. They may intensify gender-appropriate
behavior in order to deny their differences (boys going out for
sports or into the military, girls going into dance, instead of sports).
Most try heterosexual dating, but some engage in substance abuse
or suicidal ideation as they contemplate their differences.
Acceptance comes gradually, but then they have to determine how
and who to tell. Some may “pass” so they don’t have to tell, but
most eventually decide to declare their sexual orientation, first with
friends, then family and others. If people act positively, coming out
will strengthen one’s view of self as positive, achieving, with
meaningful goals to follow. They need contact with other
successful gays in order to consider all the possibilities for their
lives. Once they have come out, they can focus more attention on
other aspects of development, such as self-esteem, cognitive
development, psychological well-being, spiritual connections.
Sexually transmitted disease is most prevalent in adolescence. 1/6 sexually
active teens will contract an STD. Untreated, sterility and other health
complications can occur.
o AIDS is the most serious STD, since there is no cure and it compromises
the entire immune system. It is more common in drug-abusing teens who
share needles as well as homosexual partners of AIDS sufferers.
Heterosexual spread is more common in women. It is twice as easy for a
male to infect a female with an STD than vice versa.
Know your partner well
Maintain mutual faithfulness
Do not use drugs
Use a latex condom and vaginal contraceptive when having sex
with a nonmarital partner
Do not have sex with a person with an STD
If you get an STD, inform all recent partners
Adolescent pregnancy and parenthood has declined, but still the US rate is
higher than other industrialized countries. 40-45% of teen pregnancies end in
abortion, but most girls will just keep their babies, regardless of whether they
o Correlates and consequences of adolescent parenthood affect many
areas of their lives- developing a sense of purpose, career direction,
independence and maturity for quality parenting. They may have histories
of poor school achievement, poor parental relationships, substance abuse.
Because their parenting skills are weak, their children tend to score low on
intelligence tests, have poor school achievement and have behavior
problems. If these mothers can finish school, find a stable partner, their
chances for success in life can be better.
Educational attainment – having a baby reduces the chances of
finishing school. Only 50% of teen mothers graduate.
Marital patterns – marriage is less likely for teen mothers, and
they have greater chances of divorce.
Economic circumstances are poor, welfare is essential, and their
jobs are not very interesting and have little chances of promotion.
o Prevention strategies must address the underlying factors that set this
pregnancy in motion: lack of sex education or ineffective sex education.
Sex education that includes:
Teaching skills for handling sexual situations- role
Promoting the value of abstinence
Providing information about contraceptives and access
Building social competence
o Intervening with adolescent parents may include helping them to have
their own home, grandparent assistance, job training, health care for
mother and baby, parenting training, child care. Child support laws may
increase the fathers’ involvement with their children. Certainly financial
support will lessen the mother’s stress.
Substance abuse is rampant with teens. By the end of high school, 22% smoke,
60% have engaged in heavy drinking, over 50% have used illegal drugs, usually
marijuana. 30% have tried addictive drugs such as cocaine, amphetamines, PCP.
In the past few years, the rates have dropped somewhat. Most teens just dabble in
an effort to experiment with adult behaviors. But we have a greater problem with
illegal drugs in this country, since we have more people in poverty, which
correlates with serious drug use. Abuse means taking drugs regularly,
experiencing withdrawal, moving to harder substances, and using at the expense
of school, work, family responsibilities or relationships.
o Correlates and consequences of adolescent substance abuse have to do
with the nature of their problems- drug abusers are unhappy and act out in
an antisocial way. There may be a genetic connection, but there also may
be environmental problems- low SES, family mental health issues, family
drug abuse, lack of parental warmth, sexual or physical abuse, failure in
school. Peers who use drugs are a predictor of substance abuse. When they
space out on drugs, they aren’t developing maturity and coping skills for
adulthood. They develop depression, anxiety, and act out in unfortunate
o Prevention and treatment include on-call transportations services for
safe rides, education on consequences of drug use, parenting training in
reducing conflict, training of teens in conflict management and stress
management. Treatment may require hospitalization, monitoring, family
therapy, tutoring in academic skills. Even so, relapse occurs 35-85% of the
time. Treatment addresses the phenomenon of relapse management.
Piaget’s theory: the Formal Operational Stage is the time when teens develop abstract,
scientific thinking. Characteristics include:
Hypothetico-deductive reasoning means beginning with an overarching theory
of factors, then developing hypotheses that may answer the problem and testing
these possibilities. Teens move from possibility to reality. They can vary one
factor at a time, holding the others constant to deduce the solution of a problem.
The pendulum problem asks teens to figure out what influences the speed a
pendulum swings, using strings of different lengths, and objects of different
weights. Teens can approach this problem in a systematic way.
Propositional thought means evaluating the logic of verbal statements
(propositions) without referring to real-world circumstances. They can consider
logic using concrete evidence. Abstract thought requires language in order to
represent things which are not concrete, higher math, physics theories, etc.
o Are children capable of abstract thinking? They become much better at
propositional thinking after age 11, improving after that.
o Do all individuals reach the formal operational stage? Not all adults
use formal operations thinking, even those who are college-educated. It
depends on course content. Tribal societies have little need for this level of
thought, so they don’t master these tasks. This may be a culturally
transmitted way of thinking that comes as a result of formal education.
Information-Processing view of adolescent cognitive development
o Attention is more focused on relevant information and the demands of a
o Strategies become more effective, with better storage, representation, and
retrieval of information.
o Knowledge increases, so strategy use declines.
o Metacognition expands, allowing for more effective strategies in learning
and solving problems.
o Cognitive self-regulation improves, allowing for better monitoring and
reconfiguration of learning strategies.
o Processing capacity increases due to brain development and increased
speed of processing. More space in working memory is freed so more
information can be held at once.
Scientific reasoning: coordinating theory with evidence improves with age, as
children will distort conflicting evidence in order to hang onto a favorite theory.
Teens can distinguish a theory from evidence and use rules of logic to examine
How scientific reasoning develops – through many educational opportunities to
question theory with evidence, people get better at evaluating evidence and
applying logic. Some people are more flexible in their thought. Teens are
developing metacognitive awareness, as well as developing separate skills in
problem solving, that can eventually be combined into an effective system.
Consequences of abstract thought
Argumentativeness comes out of the advanced thinking abilities teens are
developing. They can use facts to build a case for expanded freedoms. As families
discuss rules, teens get better at debating the underlying values supporting the
rules. Teens generally hold onto parental values once they see the reason for
them. As they defend their points of view, even with other peers, they learn
debate, critical thinking, and negotiation of differences.
Self-consciousness and self-focusing comes out as a new egocentrism- an
inability to distinguish the abstract perspectives of themselves from others.
Eventually they develop a better understanding of others’ perspectives.
o Imaginary audience is the concept that teens believe they are the focus of
everyone else’s attention and concern. If they are obsessed with
themselves, surely everyone else is, too! They feel “on stage”, so they act
very self-conscious, easily embarrassed. It makes them hypersensitive to
criticism and obsessive about their appearance. They become very
preoccupied with what others think of them.
o Personal fable means an inflated opinion about their importance. They
feel special, unique, and invulnerable. Their emotionality is extreme, as
they think their experience is the first one of its kind and no one could
possibly understand. It contributes to risk-taking.
Planning and decision making is more analytical than in the past. They are
better at self-regulation, planning their study and progress toward a goal. This
planning may not transcend to social judgments, however, particularly if they
have multiple options for entertainment with various peers.
Idealism and criticism- now they can imagine the possible, even ideal, so
perfection becomes a real possibility. This opens the world up to the teen in a way
s/he has never thought about before. Their idealism encompasses visions of a
perfect world, with no poverty, pollution, hardship. They judge adults harshly for
letting things get so broken down. They don’t understand what the older
generation has been doing all this time. It contributes to a real generation gap in
understanding of possibilities. They have the energy to really work toward some
social changes, but they also have a judgmentalism that chafes adults.
Sex differences in Mental abilities
General differences: Girls are better in reading, writing, & general verbal ability.
Boys generally do better than girls in math, especially abstract reasoning,
complex word problems, geometry. At the highest levels of math reasoning, boys
outscored girls 13/1. Boys’ stronger spatial abilities seem to link to higher math
reasoning ability. Math has been seen as a masculine study, so many girls were
not encouraged to develop math abilities and rarely take the most challenging
math classes in school (unfortunately limiting their possibilities for life.)
Sex differences have decreased in the past years, as science and math are being
taught in ways that are more agreeable to girls. The more hands-on and applied
these subjects are taught, the more girls are engaged in them. Group activities
help girls to actively learn these subjects. In the past, competition in these classes
left girls with no voice, as boys blurted out answers before girls had a chance to
process the problem. Girls instinctively believed they were incompetent.
Sex differences in spatial abilities have been the greatest. Mental rotation tasks
show a large gender gap favoring boys. Males also do better on spatial
perception tasks, where people must consider the orientation separate from the
environment. These gender differences show up early in childhood. It seems that
prenatal exposure to androgens enhances right brain functioning, giving them a
spatial advantage. Girls who had high prenatal exposure to androgens do well on
spatial tasks. These biologically based differences may have resulted after
thousands of years hunting and wandering far from the camp to hunt and return.
Experience does make a difference, however, since children who have
manipulative games and toys, do better on spatial tasks. Playing video games
enhances spatial representation. Boys do these things more. Self-confidence in
math predicts higher scores, though, and boys have greater confidence in their
abilities, especially in math, despite their actual grades.
Learning in school
o Impact of school transitions can often be negative, particularly if teens
have problems adjusting to the new environment. Each transition, even
within a school system, sees grades drop. As teens move to more
responsible expectations of higher grades, they may not be able to perform
at the same level. They also get less personal attention, have larger classes
and less opportunity to participate as they get older. Self-esteem drops,
especially for girls. 6-3-3 school systems have the greatest negative impact
on girls, since girls measure their self-worth in terms of friendships and
how they fit in. Each transition challenges their relational abilities. If their
school achievement suffers, they often begin a negative spiral.
o Helping adolescents adjust- if parents can increase support, engage
teachers more, they can ease the difficulty inherent in transitions. The 8-4
school system works better for middle school children.
Academic achievement can be enhanced by positive educational environments,
encouragement of achievement, high standards, and building confidence in the
o Child-rearing practices
Joint parent-adolescent decision making
Parent involvement in teen’s education
o Parent-school partnerships
Parents keep up with teen’s progress, communicate with teachers,
and keep teens in challenging activities.
o Peer influences
Peer values for high achievement
o School characteristics
Classroom experiences that are more personal are more effective.
When teachers become mentors, students benefit from role
modeling, as well as learning high-level thinking.
Active participation in learning activities and decision-making.
Tracking or ability grouping is undesirable, since it sends the
message that ability is stable and unresponsive to training or
studying. It is stigmatizing, as well, sending the message that the
student shouldn’t have high expectations, they won’t be possible.
There is a natural sorting that occurs in response to SES, type of
school attended, learning experiences outside the classroom.
o Part-time work is a factor for half of students in the US. The jobs are
repetitive, and too much time (over 15 hours/week) relate to poorer school
attendance, lower grades, fewer extracurricular activities. Students who
work too much are distanced from parents and more apt to use drugs. They
develop a cynicism about work that contributes to burnout at an early age.
Dropping out happens for 11% of US students. It is higher for lower SES
minority youths, especially Hispanic and Native American. They lack skills
necessary for good jobs, so they remain marginally employed.
o Factors related to dropping out
Low academic self-esteem
Learned helplessness, giving up easily
Poor attentional control
Poor parental involvement in school activities, often dropouts
o Prevention strategies
High-quality vocational training
Remedial instruction and counseling
Efforts to address the factors related to dropping out
Extracurricular activities that focus on the arts, community
service, vocational development. These are structured, goal-
oriented activities that require teens to take on challenging roles
and responsibilities. They learn to be mentors to younger children
and caring helpers for older people. This enhances self-worth and
shows teens what they have to offer. They develop relationships
with good role models who expand their beliefs about their