Post on 05-Jan-2020
1
Janet Belsky’s
Experiencing the Lifespan, 2e
Chapter 8
Physical Development
Meredyth Fellows, West Chester University of PA
Puberty
�Puberty: all the hormonal and physical
changes that contribute to sexual maturity.
�Takes on an average of five years and today
is typically an early teenage change.
�Puberty rite
�Secular Trend
�Menarche and Spermarche
Puberty Trends
The Secular Trend
�Th
e re
gula
r dec
line
in
the
age
of p
uber
ty
(sig
nale
d by
men
arch
e)
in d
evel
opin
g co
untri
es.
�In 1830, the average
age of menarche in
Northern Europe was
over 17.
�Today, the age has
fallen to under 13.
The Hormonal Programmers
�Two Systems:
�Androgens-produced by adrenal glands
�Promote growth of hair; influence skin changes;
program sexual desire.
�Androgens begin secretion in middle childhood.
�HPG Axis (Hypothalamic, Pituitary, Gonad)
�Main system programming the body changes.
�Hypothalamus triggers the pituitary to secrete its
hormones, which in turn, triggers the gonadsto
secrete their hormones, which produce major body
changes.
2
The Hormonal Programmers
�Gonads
�Testes: testosterone
�Ovaries: estrogen
�Adrenal androgens (testes and estrogen)
found in both sexes
�program sexual desire and skin and
bodily hair growth
Classifying the Physical
Changes
�Primary Sexual Characteristics
�Changes directly involved in reproduction
�Growth of uterus, maturation of the ovaries, onset
of menarche.
�Growth of penis, testes, onset ofspermache
�Secondary Sexual Characteristics
�Physical changes not related to reproduction
�Hair growth, voice changes, acne, breast
development
�Growth Spurt
�Dramatic increase in weight and height
�Opposite of the cephalocaudalsequence
Puberty Timetables: Individual
Differences
�Influences
�Genetics
�Weight
�Nutrition
�Stress
3
Feelings about Puberty
�Basic Principle: changes are exciting and
frightening; reactions depend on social
norms and reactions of family
�Breast Development
�Western Cultures = pride
�Exception: girls who attempt to maintain pre-
pubescent appearance (gymnastics, etc.)
�Menstruation
�Spermarche
Feelings About Puberty
�Menstruation
�Attitudes towards menstruation vary—with
the Navajos celebrating this change and
our culture viewing it more negatively.
�Although women discuss menstruation with
their daughters, spermarche is rarely
discussed.
Maturing Early: Possible Problems for
Girls (Statistical Tendencies)
�May become involved with
older friends
�May demonstrate “mature
teenage behaviors”
�Risk of pregnancy
�Popularity among boys
�Inability to say “no”
�Risk of depression
�Self-consciousness
Wrapping Up Puberty
�Environmental context will affect child’s
reaction to puberty.
�Especially for boys, communication can
be improved.
�With early-maturing girls, take care to
arrange the best body-environment fit.
4
Interventions: Minimizing Distress
during Puberty
�For society
�Consider keeping pre-teens in smaller K-8
schools.
�Earlier introduction to sex education
�For parents
�Be alert for “acting out” behaviors in young
teenage girls
�Communication important
Body Image Issues
�Susan Harter’s research
�Feelings of competence in 5 domains
relates to overall self-esteem
�Scholastic competence, behavioral conduct,
athletic skills, peer likeability, appearance
�For adolescents, contentment with one’s
appearance outweighs any other category
Satisfaction in physical appearance in
both genders 3rdthrough 8thgrades
Other factors related to self-
consciousness
�Teasing from family
and friends
�Dating
�Media
�Presents unrealistic images
�Strong influence in
promoting body
dissatisfaction in both
genders
5
Eating Disorders
�Anorexia Nervosa
�Affects 1 in 1000 teenagers (majority girls)
�85% or less of healthy body weight
�Distorted body image
�5% Mortality rate
�Starvation can destroy body organs and
cause death
�Medical emergencies demand
hospitalization
Bulimia Nervosa
�Characteristic behavior of binging and
purging
�In addition to forced vomiting, purging
may include excess exercise
�Major consequences
�Mouth sores, loss of tooth enamel (gray
teeth), ulcers, esophageal cancer
�Prevalence is increasing
Risk Factors
�Strong hereditary component, especially
in girls
�Critical, disapproving, micromanaging
mothers
�Temperamental tendency to experience
anxiety and depression
�Low self-efficacy
�Feelings of lack of control over one’s life
6
Interventions
�Help teens to understand:
�Our personality is a strong influence in how
we appear to others.
�That feelings about oneself influence self-
perceptions
�If teens “feel” beautiful, the outside world may
agree
�People are beautiful in every size and
shape.
Sexuality
�Sexual desire is a
result of rising
levels of adrenal
androgens.
�An interplay of
nature/nurture
heightens sex
hormone levels
(illustration).
Who IS having intercourse?
�Average age late teens, but 1 in 7 begin
at age 15.
�Predictors:
�Biology: early puberty
�Intergenerational influences
�Social class and ethnic differences
�Media practices (intercourse appears as the
norm)
�Peer modeling
With whom are teens having
sex?
�3 in 4 teens report first sex often with
steady dating partner.
�Research with Ohio teenagers
�3 in 4 teens report a non-romantic sexual
encounter involved someone they know well
�Engaging in non-committed sex
�For girls, risk factor of depression
�For boys, higher self esteem (one study)
7
Sexual Double-Standard
�Cultural code that
gives men greater
sexual freedom than
women
�Research shows that
both boys and girls
put their highest
priority on intimacy.
Contemporary Trends
�4 out of every 10 girls get pregnant before
age 20.
�Fewer U.S. teenagers are having intercourse
(and use condoms when they do).
�Oral Sex
�Not perceived as “real sex”
�Those reporting onlyoral sex
�Young teenagers
�Affluent, upper-middle class