They are dramatic, irrational
and scream for seemingly no reason. And they have a deep need for both greater
independence and tender loving care.There is a reason this description could be
used for either teens or toddlers: After infancy, the brain's
most dramatic growth spurt occurs in adolescence."The brain continues
to change throughout life, but there are huge leaps in development during
adolescence," said Sara Johnson, an assistant professor at the Johns
Hopkins Bloomberg School of Public Health who reviewed the neuroscience in
"The Teen Years Explained: A Guide to Healthy Adolescent Development"
(Johns Hopkins University, 2009) by Clea McNeely and Jayne Blanchard.
And though it may seem
impossible to get inside the head of an adolescent, scientists have probed this
teen tangle of neurons. Here are five things they've learned about the mysterious
teen brain.
1. New thinking skills
Due to the increase in brain
matter, the teen brain becomes more interconnected and gains processing power,
Johnson said. Adolescents start to have the computational and decision-making
skills of an adult – if given time and access to information, she
said.
But in the heat of the moment,
their decision-making can be overly influenced by emotions, because their brains
rely more on the limbic system (the emotional seat of the brain) than the more
rational prefrontal cortex, explained said Sheryl Feinstein, author of
"Inside the Teenage Brain: Parenting a Work in Progress" (Rowman and
Littlefield, 2009)."This duality of adolescent competence can be very
confusing for parents," Johnson said, meaning that sometimes teens do
things, like punch a wall or drive too fast, when, if asked, they clearly know
better.
2. Intense emotions
"Puberty is the beginning
of major changes in the limbic system," Johnson said, referring to the
part of the brain that not only helps regulate heart rate and blood sugar
levels, but also is critical to the formation of memories and emotions. Part of
the limbic system, the amygdala is thought to connect sensory information to
emotional responses. Its development, along with hormonal changes, may give
rise to newly intense experiences of rage, fear, aggression (including toward
oneself), excitement and sexual
attraction.
Over the course of adolescence,
the limbic system comes under greater control of the prefrontal cortex, the
area just behind the forehead, which is associated with planning, impulse
control and higher order thought.
As additional areas of the brain
start to help process emotion, older teens gain some equilibrium and have an
easier time interpreting others. But until then, they often misread teachers
and parents, Feinstein said.You can be as careful as possible and you still
will have tears or anger at times because they will have misunderstood what you
have said," she said.
3. Peer pleasure
As teens become better at
thinking abstractly, their social anxiety increases, according to research in
the Annals of the New York Academy of Sciences published in 2004.
Abstract reasoning makes it
possible to consider yourself from the eyes of another. Teens may use this new
skill to ruminate about what others are thinking of them. In particular, peer
approval has been shown to be highly rewarding to the teen brain, Johnson said,
which may be why teens
are more likely to take risks when other teens are around."Kids are
really concerned with looking cool – but you don't need brain research to tell
you that," she said.
Friends also provide teens with
opportunities to learn skills such as negotiating, compromise and group
planning. "They are practicing adult social skills in a safe setting and
they are really not good at it at first," Feinstein said. So even if all
they do is sit around with their friends, teens are hard at work acquiring
important life skills.
4. Measuring risk
"The brakes come online
somewhat later than the accelerator of the brain," said Johnson, referring
to the development of the prefrontal cortex and the limbic system respectively.At
the same time, "teens
need higher doses of risk to feel the same amount of rush adults do,"
Johnson said.
Taken together, these changes
may make teens vulnerable to engaging in risky behaviors, such as trying drugs,
getting into fights or jumping into unsafe water. By late adolescence, say 17
years old and after, the part of the brain responsible for impulse control and
long-term perspective taking is thought to help them reign in some of the
behavior they were tempted by in middle adolescence, according to McNeely and
Blanchard.
What is a parent to do in the
meantime? "Continue to parent your child." Johnson said. Like all
children, "teens have specific developmental vulnerabilities and they need
parents to limit their behavior," she said.
(Research on the different rates of brain
function development during adolescence was published in the journal
Developmental Review in 2008.)
5. 'I am the center of the universe'
The hormone changes at puberty
have huge affects on the brain, one of which is to spur the production of more
receptors for oxytocin, according to research detailed in a 2008 issue of the
journal Developmental Review.
While oxytocin is often
described as the "bonding
hormone," increased sensitivity to its effects in the limbic system
has also been linked to feeling self-consciousness, making an adolescent truly
feel like everyone is watching him or her. According to McNeely and Blanchard,
these feelings peak around 15 years old.
While this may make a
teen seem self-centered (and in their defense, they do have a lot going
on), the changes in the teen brain may also spur some of the more idealistic
efforts tackled by young people throughout history.
"It is the first time they
are seeing themselves in the world," Johnson said, meaning their greater
autonomy has opened their eyes to what lies beyond their families and schools.
They are asking themselves, she continued, for perhaps the first time: What
kind of person do I want to be and what type of place do I want the world to
be?
Until their brains develop
enough to handle shades of gray, their answers to these questions can be quite
one-sided, Feinstein said, but the parents' job is to help them explore the
questions, rather than give them answers.
Seahorses reproduce in an unusual way: the male becomes pregnant.
Pipefishes and seahorses are the only species in the animal kingdom to
which the term "male pregnancy" has been applied.
