being a teenager is hard and so is
living with one I'm told a human gets to
escape this moody angsty confusing phase
and interestingly such an extended
adolescence is unique to humans other
animals grow up a lot faster than we do
and you may think our teen years are
just about streamlining bodies for
baby-making but as it turns out the
storms of sex hormones that we associate
with the teenage years are only a small
part of what's really going on in the
teenage body most of the action it turns
out is happening in the brain until
fairly recently we thought that the
brain finished the nuts and bolts of its
development by the time we started
kindergarten but really right as puberty
rolls in it undergoes massive remodeling
this amounts to several years of neural
growing pains as well as the other more
visible growth that's going on all over
your body so take heart whether you're
going through it now are about to go
through it or count yourself among the
veterans of that turbulent decade know
that the result of the teen years is a
stronger faster more sophisticated brain
because I'm gonna tell me that 20 years
ago
let's start with that obvious scapegoat
of adolescent anguish hormones
Howard itself is kind of a lazy
shorthand that people use to describe
the chemicals that some of our glands
excrete that can affect our behavior in
fact is hormones have all kinds of jobs
that have nothing to do with where you
grow hair or what turns you on or
whether you feel glum for no apparent
reason hormones keep your heart beating
and your body hydrated and they make
your organs grow and make you grow bone
and muscle and skin people actually mean
when they talk about teenage hormones
are sex hormones and yes puberty
involves a whole series of sex hormone
storms the first of which actually kicks
in before you're out of primary school
that's when the adrenal gland starts
secreting androgens which trigger the
growth and activity of the skin
sebaceous glands making skin more oily
soon enough more apocrine or sweat
glands get activated increasing body oh
then comes the wave of hormonal agents
that start activating the gonads for
boys this influx of luteinizing hormones
from the pituitary gland get
testosterone brewing in the testes and
suddenly that guy has up to 50 times
more testosterone than he did before
puberty this also changes the shape of
the male body promoting hair growth and
building up lean muscle mass just as the
increased presence of estrogen and girls
rearranges the deposition of their fat
stimulating the growth of breasts humans
are actually lucky to experience the
craziness of puberty only once many
other animals undergo multiple similarly
intense hormonal rodeos as they enter
sexually active periods sometimes called
the rut or heat every new breeding
season some male species completely stop
eating during their breeding period
because they're just that sex-crazed and
yet all that said teens are far less
ruled than their hormones than you might
think there are other factors at play
here for example your favorite Moody
teen may be by turns punchy angry
depressed or in a zombie-like fog
because of their chronic lack of sleep
sleeve is vital to everyone but it's
especially important for kids and teens
because it's during sleep that your
pituitary gland releases an essential
growth hormone necessary for development
a normal sleep cycle driven by circadian
rhythm is regulated by the daytime
release of cortisol which helps you wake
up and melatonin which helps you wind
down when it gets dark but this biology
of sleep timing changes as we age and as
puberty begins teens sleep clocks get
pushed back most adults start using
militant
around 10:00 p.m. ish but one study
showed that teenagers don't start
producing melatonin until closer to 1
a.m. this may be because puberty
hormonal frenzy is stalling the release
of melatonin and could partly explain
why so many teens stay up late energized
by the night but had a really hard time
rolling out of bed with the alarm of
course it's a bit of a chicken and egg
deal since watching reruns of The
Simpsons and playing call of duty later
to the night continues to stimulate the
brain which may further delay the
release of melatonin still some
researchers are starting to advocate for
pushing back high school start times in
the morning in the hopes of having more
focused students so we got sex hormones
changing the bodies and a lack of sleep
to contend with but increasing evidence
suggests that there is something much
bigger at work that's making teenagers
so teenager eat their brains it turns
out that brains actually take longer
than we thought to fully mature I don't
mean physical size our brains are
already about 95% full size by the time
we're just 6 but more in the sense of
the connections inside the brain adults
for the most part know how to make
decisions by evaluating choices and
weighing consequences they do this with
their prefrontal cortex which is
responsible for controlling impulses and
emotions and forming judgments
it's neurons chat with the neurons in
other regions of the brain response will
force a memory or movement through
synapses thing is teenage brains don't
quite work like this yet the prefrontal
cortex may not be fully developed until
your mid-20s and teen synapses those
lines of communication are still growing
and specializing they're also slow as an
adolescent brain keeps developing its
axons the long tail like parts of the
neurons that transmit signals to other
neurons become more and more insulated
by a fatty layer called the myelin
sheath this padding greatly increases
the cells transmission speed and while
it helps adults make faster decisions it
isn't fully formed in teens these
changes occur slowly beginning at the
back of the brain where the oldest and
most fundamental brain parts reside and
slowly working its way forward to the
more advanced and complicated brain bits
the prefrontal cortex is the last to be
hooked up and shaped so it's important
to keep in mind that just because your
favorite teenagers stayed up until
sunrise binge watching The Walking Dead
the night before an exam it doesn't mean
they're dumb or lazy their brains are
just literally finishing being
at the same time because all this brain
building is just starting to peak this
is also when the brain starts getting
thinned out you actually start losing
connections that you don't use enough in
a process called synaptic pruning which
has led to a theory that this is kind of
a use it or lose it phase meaning
adolescence could be an especially
important time to use your brain play an
instrument engage in sports write poetry
learn a language because by doing these
things you're helping hardwire those
synapses in giving your brain topiary a
lovely lasting shape whereas if you're
sitting around all day playing candy
crush those will be the connections that
survive what you don't need this shaping
of the teen brain manifests itself in
other ways too like in teenage attitudes
a group of scientists at the McLean
Hospital in Massachusetts once hooked up
the group of adults and a group of teens
to MRI devices and then asked them to
identify a series of expressions on
photographs of adult faces interestingly
while adults correctly identified one
expression as fear the teenagers thought
the faces showed anger surprise or shock
they weren't registering subtlety as
well not only that but the MRI images
showed that adults and teens responded
with different parts of their brains
adults used the reasonable prefrontal
cortex while the teens mostly used the
gut reaction emotional amygdala located
farther back in the brain it sounds like
these might help explain why teenagers
seem to experience frequent mood swings
for one they tend to react quickly from
the emotional part of their brain
without running those reactions by the
more rational frontal cortex and - it
could be that they're just miss reading
expressions and therefore the intentions
behind the frontal cortex also helps
people relate to and understand each
other and you can imagine what happens
when concern is misjudged as anger or
worry as disappointment the Fresh Prince
has an entire song about it but the
truth is as much as parents just don't
understand
teens don't always understand either
when the emotional amygdala and the more
rational cortex aren't fully hooked up
yet that can make it hard for teenagers
to productively work through emotions
this kind of reactionary impulsive
behavior may also lead to more
risk-taking adolescence is the time when
we're most likely to experiment with
whatever booze drugs or toad licking is
available and unfortunately it's also
the time our developing brains are most
vulnerable to lasting effect studies
have shown that teens are more likely to
become addicted to drugs and alcohol
than adults partly because their brains
are more attune
to their reward centers now the teenage
prefrontal cortex is still developing
their nucleus accumbens or pleasure and
reward zone forms early on neuroimaging
studies have shown that when presented
with a big potential reward teen brains
light up way more than kids or adults
brains but if the reward was small teen
brains hardly fired at all
so basically giving out a lesson to pat
on the back and you'll get a shrug give
them a hot date or a winning goal and
their brains light up like Vegas this of
course does not always result in great
judgment a jacked up thrill seeking
impulse combined with an exquisite pang
of peer pressure plus a new drivers
license new sex parts and access to
substances can lead to some not good
results but still this long and
sometimes tedious remodeling process
that our bodies go through in the
teenage years isn't all bad many
scientists have pointed out that our
delayed adolescence lets our brains keep
their flexibility longer which yeah may
make teens a little slow but also more
adaptable as they prepare for the adult
world in this way you can see teen
impulsiveness as boldness or independent
thinking and moodiness as a source of
newfound empathy and excite ability as
passion which means there's a lot of
Awesome energy floating around out there
ready to decrease all kinds of world
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