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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.

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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

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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.

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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

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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

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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)

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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