|
September 11, 2001....We discussed how this event has and has not
changed our daily lives, and how it may have affected adolescents. |
|
Then we reviewed the three domains of development in adolescence
(biological/physical, cognitive, and psychosocial), and the contexts
(family, peer groups, schools, work/leisure and religious contexts) in which
these developments unfold. Last, we reviewed the main psychosocial issues
that adolescents deal with (identity, autonomy, intimacy, sexuality and
achievement). We talked about Bronfenbrenner's ecological model of development, a way
of looking at how interactions between an individual and his/her
environment affect that individual's development. Brenfenbrenner's
model:
the Microsystem
|
Adolescents are most directly affected
by what Bronfenbrenner refers to as the 'microsystem'. This consists
of the immediate (face-to-face) environment in which direct
interactions take place: direct relationships with parents and
family members, teachers, peers, etc and environments such as home,
school, recreational and leisure activities, peer interactions
|
the Mesosystem
|
Next, adolescents are affected by interactions
that occur between aspects of their microsystem which do
not include them directly. For instance, a parent-teacher
conference may have effects on the
child's intellectual development and friendships
between the parents of one’s friends (peers) may influence the
adolescents’ social life.
|
the Exosystem
|
The next level of the social environment which
affects an adolescent’s life are not ones that the individual
experiences directly but which still have a direct impact on
that person’s life. These can include the parent’s workplace or
job which may affect the family income or the amount of time the
parent has to spend with the adolescent, or a friend’s family (
which may move away, taking that friend from the individual’s
everyday life).
|
and the Macrosystem
|
At the broadest and most distant level of
influence are the social and cultural influences which still
directly and indirectly shape the world in which all the other
environments exist. These include cultural, legal, historical,
economic, religious influences that impose structures,
possibilities, responsibilities, limitations and expectations on
what the adolescent does and thinks or feels. Examples include laws
concerning mandatory schooling or ‘status crimes’, or economic
conditions that determine what a person’s opportunities for work
are, restrictions on behavior that religious beliefs impose, etc.
|
This model is useful in thinking about the
factors that affect adolescent development.
Next we reviewed the three levels of developmental
factors that shape the adolescent's experience:
First, all adolescents, regardless of time. place and
culture, share some universal aspects of development. These include
the changes of puberty, the development of new cognitive capacities, and the
social transitions between childhood and adult roles and status. The
physical aspects are genetically encoded and therefore similar in their
progression throughout the world (with minor variations due to some
genetic differences and physical and psychological environmental factors, as
discussed in Chapter 1). Cognitive developments are more influenced by
environmental factors: different cultures, historical epochs, economic
situations, etc may encourage or inhibit the development of a person's
inborn cognitive potential. Social transitions occur in every culture
between childhood and adulthood, but the form, timing, and meaning of these
transitions vary from one culture or historical period to the next; only the
fact that these changes in roles, responsibilities, rights and
privileges occur for adolescents in every culture makes this a universal
aspect of this stage of development. Thus, the second level of factors
affecting development are the cultural and social factors that dictate
the social parameters of 'adolescence'.
|
|
Topic: The biological changes of adolescence and the psychosocial impact
of aspects of these bio1ogical changes..
1. The "Nature versus Nurture" view
of development:
- "Nature" refers to the genetic potential for development
which is set at the point of conception. (If, in the parents'
families, no one has ever been taller than 5'2", a child's
potential for growing to be over 6" tall is slim to
non-existent!) "Nature' sets the parameters for what is possible,
including the onset and progression of puberty.
- "Nurture" refers to everything in the environment that
affects an individual's development from conception on. (Not just from
birth on: prenatal influences have profound effects on the growth and
development of an embryo or fetus. For instance, lack of folic acid in
the mother's diet has been found to be the cause of spina
bifida, a birth defect that can cause retardation, paralysis, and
sometimes death.)
We saw a short video on physical development and sexual
maturation and how these affect adolescent's psychosocial development.
1. Puberty: (Latin: pubertas = 'adult') The period
during which an individual becomes capable of sexual reproduction, but also, all the physical changes between child and
adult.
The physical
changes of puberty include:
- rapid growth in size/weight
- development of primary sexual organs (gonads)
- development of secondary sexual characteristics: adult appearance of genitals,
breasts, facial/body hair
- changes in body composition (fat and muscle and how they are distributed)
- development of adult facial features
- changes in brain structure/function
- changes in circulatory and respiratory system
- side effects of these changes: emotional, coordination, may develop need for
glasses, braces, deodorant, may have oily skin and acne
2. Endocrine system's role in puberty: Produces, circulates
and regulates levels of hormones through input from hypothalamus (a
part of the brain which acts as a 'thermostat', monitoring levels of
hormones) to pituitary (master gland which sends out 'orders' to
other endocrine glands) to thyroid and adrenal glands, which stimulate and
regulate physical growth, and the gonads (sex glands, testes
in male and ovaries in female) which then produce sex hormones (Testosterone
from testes and estrogen from female) which are released into the
bloodstream and, in turn, affect brain and rest of body, stimulating
development of the secondary sexual characteristics.
At puberty, a reduction in the sensitivity of the hypothalamus to the sex
hormones in the blood to the brain causes the pituitarty to send a message
to the gonads to step up their production of those hormones, activating
pubertal growth and development.
The role of hormones: a) in prenatal organizing of
male/ female brain/body/behavior (may not show up 'til adolescence)
b) in activating the changes in body/behavior at puberty
- menarche: the beginning of menstruation in puberty
for girls. This is neither the beginning nor the end of puberty: the
processes of development occur before menarche and a girl does not
become fully capable of reproduction until several years after menarche.
- andrenarche: refers to the maturation of the adrenal glands in
preadolescence, resulting in an increase in the secretions of sex
hormones, with higher levels of androgens produced in males than
in females. Accounts for some of the differences in development at
puberty.
3. The pubertal changes in the primary sexual
characteristics consists of the growth and maturation of the gonads.
The secondary sexual characteristics are the development of all other
(not the gonads) sexual characteristics. The development of these
characteristics in boys tends to follow a standard pattern but is less
regular among girls. (For a general listing and outline of these
developmental sequeces, see the chart on page 28.)
4. Aside from the growth, development and maturation of the
sexual characteristic of the adolescent, they also experience changes in
physical size, shape and body composition during puberty.
- Due to stimulation of growth hormones (pituitary and thyroid)
the adolescent experiences a growth spurt, a period of rapid
acceleration of height and weight. In addition, bone density changes.
Head, hands and feet tend to start growing first, then arms and legs,
and last, toprso and shoulders. This uneven growth is called 'asynchronicity'
and results in the awkward movement and gawky appearance of many
adolescents.
- Body shape/structure changes from the straight up and down appearance
of childhood to the wider shoulders of the males and wider hips of the
females.
- In addition to the underlying bone structures' changes (shoulders and
hips), body composition changes in adolescence, with differential rates
of growth in musculature and body fat. These increase for both sexes,
but males tend to gain more muscle and females more fat. The
resulting muscle to fat rations average 3:1 for boys and 5:4 for girls.
- This increase in body fat and the resulting 'curves' of girls at
puberty, combined with the enormous emphasis on looking thin in our
society has resulted in dieting and the development of eating disorders
(anorexia and bulimia) for many adolescent girls. (These disorders
do occur in boys, but rarely. Society's emphasis on boys developing
strength and 'manly'-looking muscles, however, has led a number of
adolescent males to the use of steroids to improve their muscular
appearance.)
5. Timing and tempo (when puberty begins and how rapidly it
procedes) vary a great deal among adolescents, but females tend, on average,
to be about two years ahead of boys.
We reviewed the male and female differences in developmental time tables
and how psychosocial development is affected differently by early and late
development in males and females.
- The timing/tempo of puberty reflect both 'nature' (inherited genetic
influences) and 'nurture' (the effects of the environment on the
individual's growth and development), just as eventual adult height and
body type do. Nutrition, exercise and many other influences affect
whenpuberty begins and how long it takes. This is an exciting area for
research and new aspects are constantly being published (Examples:
influences on early-onset puberty in girls discussed in class). A
pattern of earlier menarche called the 'secular trend' is noted
in the text as being due to better nutrition, sanitation and health
care, but this appears to be leveling off at about 13 years in most
industrialized nations..
- Puberty affects adolescents in terms of 1)moodiness, 2)
family relationships, and 3)self-esteem. The timing/tempo of puberty has
different psychosocial effects on males and on females, both because of
the emphasis in our society on 'perfect' body types, because of the
attentions and expectations other place on older-appearing adolescents,
and because of the match or miss-match between physical changes and
emotional and cognitive growth.
- It is advantageous for boys to mature early and late maturers
are likely to have poorer self-esteem. Girls, however, are at a
disadvantage if they mature early, doing poorly in a number of measures
of psychological well-being. Late maturing boys and girls have some
negative effects on their self-esteem. However, both late-maturing boys
and early-maturing girls may also be forced to develop coping skills in
dealing with these situations; these skills may then serve them well in
their adult lives.
|
