Period of transition:
- Early adolescence
o 10-13 years
o Pre-pubescence
- Mid-adolescence
o 14-17 years
o Pubescence
- Late adolescence
o 18-21 years
o Post-pubescence
Changes depend on and interact with environmental factors and vary across contexts.
- Bronfenbrenner: Ecological perspective on human development
o We cannot understand development without examining the environment in
which it occurs
Stereotypes about adolescence (and why they are not true):
Adolescence is …
- A distinct stage of development
o Adolescere – to grow into adulthood
o Adolescence spans the second decade of life and is a period of transition
wherein a person’s biological, psychological and social characteristics go from
childlike to adult-like, rather gradually.
- A period of universal storm and stress
, o Approximately 20-25% of adolescents report significant behavior problems.
Of these, 80% also experienced problems in childhood
o So, less then 10% of children develop problematic behavior during
adolescence.
Most of them engage in adolescent-limited deviance
- When ‘new’ hormones develop
o While horonal levels do increase during adolescence, these hormones are
present during infancy.
Until 8 weeks after gestation, all brains are ‘feminine’
Increases in testosterone levels around 8 weeks after gestation
‘masculinize’ the brains of males
These prenatal effects of hormones on brain development can appear
during adolescence
- When relationships with parents become less important
o Friends/romantic partners do become increasingly important relationships
during adolescence
o But, parent-child relationships are ‘transformed’ according to the
expectations, needs and fuctions of these dyadic relationships and
relationships between all family members
o Importance of high-quality parental relationships remains throughout
adulthood
Scientifically based data:
- Adolescence is:
o A period of (semi-) continuous biopsychosocial transition
o Not typically characterized by storm and stress,
o When levels of existing hormones increase,
o When peer relationships supplement parent-adolescent relationships, they do
not supplant them.
Lecture 2: Biological transitions
Puberty:
- Term comes from Latin word ‘pubertas’ (adult)
- It is the period during which an individual becomes capable of sexual reproduction
- Hormones regulated by the endocrine system lead to physical changes
- No new hormones are produced and no new bodily systems develop at puberty
A gradual, ‘universal’ proess resulting in reproductive capability and physical maturation:
1. Growth spurt
2. Development of primary and secondary sex characteristics
3. Changes in percentage muscle and fat
4. Changes in circulatory and respiratory systems
NO new hormones are produced
NO new bodily systems develop
,The endocrine system:
- Produces, circulates and regulates hormone levels in the body
o Hormones: specialized substances secreted by endocrine glands
o Glands: organs that stimulate particular parts of the body to respond in
specific ways
o Gonadotropin-releasing hormone (GnRH) neurons: neurons in the brain that
play important roles at puberty
o Hormonal feedback loop (HPG axis)
o Set point (e.g., thermostat)
o Adrenarche: the maturation of the adrenal gland that takes place during
adolescence
Just before puberty, the pituitary begins to secrete hormones that act
on the thyroid and on the adrenal gland, it also stimulates homrones
that prompt growth.
Changes in the brain system regulate the adrenal gland, which is also
the system that controls how we respond to stress
Cortisol: a hormone that is produced when a person is exposed to
stress
What triggers puberty?
- Something in the middle childhood reawakens the HPG axis and signals that the body
is ready for puberty:
o Presence of mature sexual partners
o Sufficient nutritional resources
o Physically healthy enough to begin reproducing
- Onset of puberty is stimulated by certain brain chemicals:
o Kisspeptin: a brain chemical believed to trigger the onset of puberty
, o Leptin: a brain chemical produced by the fat cells that may play a role in the
onset of puberty through stimulating kisspeptin
o Melatonin: a hormone secreted by the brain that contributes to sleepiness
and that triggers the onset of puberty through its impact on kisspeptin
- Other factors:
o Genes predispose onset at a certain age
o More fat cells and more exposure to light trigger puberty earlier
How hormones influence adolescent development
- Organizing role
o Prenatal hormones ‘program’ the brain to be masculine or feminine (like
setting an alarm clock)
o Patterns of behavior as a result of this organization may not appear until
adolescence (e.g. sex differences in aggression)
- Activating role
o Increase in certain hormones at puberty activate physical changes (e.g.
secondary sex characteristics)
Somatic development
- Effects of hormonal changes of puberty are remarkable
o Individual enters puberty looking like a child; within 4 years or so, has the
physical appearance of a young adult
o The average individual grows about 10 inches taller, matures sexually and
develops an adulted proportioned body.
o The brain changes in size, structure and function at puberty
The adolescent growth spurt:
- The simultaneous release of growth hormones, thyroid hormones, and androgens
stimulates rapid gains in height and weight
o Adolescent growth spurt – the dramatic increase in height and weight that
occurs during puberty
o Peak height velocity – the point at when the adolescent is growing most
rapidly
o Epiphysis – the closing of the ends of the bones, which terminates growth
after the adolescent growth spurt has been completed
- Body dissatisfaction among adolescent girl. Sex differences in muscle and fat.
o Increase in height is accompanied by increase in weight, which results from an
increase in both muscle and fat.
o End of puberty: boys’ muscle-to-fat ratio is 3 to 1; girls’ ratio is 5 to 4
o Rapid gain in fat frequently prompts girls to become overly concerned about
their weight
o Girls most susceptible to feelings of body dissatisfaction with their bodies are
those who mature early and begin dating early
o Boys’ feeling about their looks revolve around how muscular they are
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller fleurpas01. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $6.28. You're not tied to anything after your purchase.