Transcript A circuitous journey “to and through” the TEEN BRAIN

A circuitous journey “to and
through” the TEEN BRAIN
“If Abraham’s son had been a teenager, it
wouldn’t have been a sacrifice.” ---Scott Spendlove
The age-old question:
“What’s the matter with kids today?”
• The age-old answer: “Nuthin’—they’re just
kids…”
But, let’s start from the very
beginning…
Embryology
• How much
embryology did I get
in Nursing School?
• Hmmm…the sperm
meets the egg…and
then…
Yes, the sperm DOES meet the egg, but
let’s quickly dispel a long-standing
myth…
• MYTH: The sperm is the aggressor
The egg is passive.
Not. The egg is 1,000x bigger than the
sperm—the egg is the aggressor
• The sperm is passive
• The egg sends a
signal telling the
sperm how eager she
is to meet him and
which Fallopian tube
to swim up
Freshly ejaculated sperm has
absolutely NO IDEA which way to swim
• Which way do we go,
George? Which way
do we go?
The Y-carrying sperm and the X-carrying
sperm
• The sperm carrying the Y chromosome is the faster
swimmer…this explains why:
• Male embyros outnumber female embryos by ~115 to
100
• Why do they swim faster than the sperm carrying the X
chromosome?
• The sperm carrying the Y chromosome is much lighter
than the sperm carrying the X chromosome
• The sperm carrying the X chromosome is HEAVY
Let’s head back to the womb…
• Sexual differentiation in the embryo can “go either way”
until the 8th week of gestation
• The Sry region on the Y chromosome kicks in
• The boy starts producing testosterone from the testicles;
girls??
• Mom sends adrenal androgens across the placenta for
both boys and girls, so…
• Boys get 2 hits of testosterone; girls 1 hit
Clinical implications
• Development of the brain en utero—
testosterone influences communication
patterns, behavior and the limbic system,
as well as the basal forebrain and
cognition
• Boys receive a double hit of testosterone
to the limbic system—influencing the
fight/flight (assertive/aggressive)
response; libido and sexual function
In fact…
• Many pregnant moms say they “KNOW”
it’s going to be a boy…kicking and
tumbling…more active and aggressive en
utero
Testosterone and sex drive
• The area of the limbic system responsible
for sex drive in the male is double the size
of the area in the female
And then a 3rd hit of testosterone
during puberty!!
• The testicles kick in!
• Puberty kicks in, testosterone levels
increase 10-fold and sex becomes an
obsession
• Teenage boys think about sex about every
52 seconds
Testosterone in the female brain
• Communication areas—verbal areas are larger;
women on average, talk and listen a lot more
than men; Pathways mature faster
• Girls tend to speak earlier than boys; by 20
months we have double or triple the vocabulary;
speak faster (250 wpm/125);
• 20,000 words per day vs. 7,000 in boys
• In colonial times, women were punished for the
crime of “talking too much”
The anatomy of the teenage brain
• Since the brain reaches its full size by age 5, it
was assumed by most of the scientific
community that the brain was fully wired by the
end of childhood and that subsequent wiring
only involved “fine-tuning”
• WRONG assumption.
• Let’s take a look at the various areas of the
brain.
The prime real estate of the brain—
the frontal lobe
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•
•
The prefrontal cortex
The motor association area
The motor cortex
Broca’s area—voluntary speech and
communication
• (the last 2 areas are well-developed in early
adolescence, however the prefrontal cortex and
the association areas are immature in teenagers
and continue to develop into their early 20s)
So, what is the prefrontal cortex?
• It’s the center for judgment, insight,
reasoning, organization, future planning
and problem solving, and it has extensive
connections with the emotional and
instinctual centers in the limbic system,
especially the amygdala. These levels are
critical for emotional learning and highlevel self regulation.
An easier way to put it…it’s your
MOTHER!
• And MOM is inhibitory---what’s the only word a MOM
needs to know?
• NO.NO.NO.NO.NO.
• Socialization
• She puts the checks and balances on behavior—
especially on the amygdala—the wild beast within
(the instinctual nucleus of the brain)
• Parents, who act like parents, do this for teenagers;
parents who act like teenagers, do not
The anterior cingulate gyrus of the
prefrontal cortex
• Weighs options, makes decisions
• The worry-wort center—larger in women
than in men
• Girls brains mature faster; pruning starts
earlier than boys; girls move more quickly
toward maturation of all brain circuits and
mature 2-3 years earlier than boys
Pruning the way to a mature brain
• Neurons and synapses proliferate in the
prefrontal cortex in childhood and
preadolescence and they are they
gradually “pruned” throughout
adolescence
• Eventually more than 40% of all synapses
are eliminated, largely in the prefrontal
cortex and association cortex
Dr. Peter Huttenlocher—University
of Chicago
• Opened the door to understanding the brain’s “plasticity”
• made a big splash when he reported findings on how the
number of synapses change from prenatal to
adolescence
• Found that at times, synapses were forming in a new
brain at the incredible rate of 3 billion/second
• 28 week old fetus—124 million connections
• Newborn—253 million
• 8 months—572 million
• 10 years—500 million
• 12 years—354 million
• Pruning disorders? Schizophrenia? Bipolar? Autism?
Neuronal dropout over the first 21
years
• It’s not just pruning
• Neuronal dropout as well throughout the
brain
• # of neurons at birth;
• # at 21;
• # at 75
Pathway maturity
• In addition, myelin sheaths covering the pathways
continue to accumulate, gradually improving the
precision and efficiency of normal communication—
completed in the early 20s
• Especially the large bundle connecting the two
hemispheres with the limbic system—the corpus
callosum
• And the pathways connecting the prefrontal cortex with
the limbic system
September 13, 1848
• The day that marked a watershed in our understanding
of the human brain
• An explosion at a railroad work site rocketed a 3’ 7”
tamping iron through the head of Phineas Gage,
severely injuring the prefrontal lobe of the brain
• After the wound healed, he retained all of his mental
faculties
• However, his personality differed dramatically from what
it had been
• Formerly temperate, restrained and reliable, Gage
became…
• “fitful, irreverent, indulging at times in the
grossest profanity, manifesting but little
deference for his fellows, impatient of
restraint or advice when in conflicts with
his desires, at times pertinaceously
obstinate, yet capricious and vacillating,
devising many plans for future operation,
which are no sooner arranged than they
are abandoned.” –Dr. Gage’s physician
Sounds just like…
• The teenage brain!
Speaking of which…Dr. Walter Jackson
Freeman (1895-1972)
• $200 fee for lobotomies for
“rambunctious” teenagers” in the
early 1960s
• Traveled the country visiting state mental
hospitals in an RV dubbed the
“lobotomobile”
• Neurologist with NO surgical training
performed 3,400 lobotomies
Another historical
highlight…November 1, 1998
• Fred Gage, PhD. (Scripps Institute, La Jolla, CA)
• Great, great grandson of Phineas Gage (the guy with the
tamping rod)
• Along with Gerd Kemperman (Karolinska Institute,
Stockholm, Sweden) published the first proof that
neurons could actually regenerate in the hippocampus—
the gateway to memory and learning
• HUGE finding in the world of Neurology
• Defied the central and compelling dogma that neurons
could not regenerate and, that you had all of your
neurons at birth or shortly thereafter
• WHY DIDN’T THIS MAKE THE HEADLINES???
Digression…
• If we have the capacity to build new
neurons, how can we help the process?
• Say YES to meditation
• Say YES to exercise
• Say YES to antidepressants and other
drugs
Say YES to drugs…antidepressants in
particular…
• Why does it take so long for
antidepressants to work?
• Why is this important to know????
• To help kids get through the first 3 to 6
weeks
Depression in children
• Prozac is still the only drug approved by the FDA
for the treatment of depression in children and
adolescents
• Prozac has a longer t½ life
• Makes withdrawal more gradual
• Keeps levels steady if a dose is missed
(teenagers in particular often miss or skip doses)
• How about a pet?
Psychotherapy…
• A large government-financed trial recently found
that Prozac worked better than talk therapy in
helping teenagers overcome depression
• That doesn’t mean that psychotherapy isn’t
beneficial
• Cognitive Behavioral Therapy—decrease
negative thinking; anti-rumination strategies
(most often when alone; call a friend; change
what you’re doing)
Should you consider treating?
• For every adolescent between ages 15-19,
every 1% increase in the use of antidepressants
corresponds to a drop in suicide rates (.23 per
100,000 per year)
• Untreated depression increases the risk of
severe depression in adulthood and the
development of bipolar disease and personality
disorders
• 19% of high-school students have suicidal
thoughts
The suicide controversy
• Potential for suicide is highest in anyone being
treated when their dosage is changing up or
down
• Suicide risk is highest in first 3-6 weeks of
treatment—because the drugs AREN’T working
yet!!
• Antidepressants are associated with an
increased risk of suicidal thoughts in about 1 in
50 who take it, but you can’t distinguish that one
patient from the 8 or 9 in 50 depressed
teenagers who would also be at risk of suicide
because of underlying depression
Does depression run in families?
• Nature or nurture?
• Is there a gene?
• Mirror neurons may play a major role in a
child growing up with a depressed parent
or caretaker
• What are mirror neurons?
• Mirror neurons (Allow us to understand others
actions and understand how others feel— “I feel
your pain/your joy/your sorrow…”)
• If you are raised in a household with depression
does this increase your risk because of the
mirror neuron theory?
• Is depression contagious?
• The area of joy in the frontal lobe is
underdeveloped when children are raised by
depressed caretakers
The “stress-related” theory of
depression
• The hormones of stress (cortisol and epinephrine) levels
decrease serotonin levels and norepinephrine levels in
the brain
• High levels of cortisol KILL brain cells that produce
serotonin
• Chronic stress and depression may go hand in hand
• Kids and stress today…have to get into the best schools,
make the best grades, be the best at soccer, take the
most advanced classes…whoa!
The Limbic system
• The limbic areas (emotional areal) mature
earlier than the prefrontal cortex;
DISCONNECT BETWEEN THE TWO
• This discrepancy between expressing
feeling vs. thoughtful evaluation accounts
for many of the teen behaviors that dismay
parents and teachers…
• “but he was such a sweet little boy…”
The Teenage Brain
• “I just don’t understand what happened…”
• “God’s way of making separation with
children was to invent adolescence.”
--Mark Patinkin
• How many times a day does a parent say
to their 16-year-old…
• “What were you THINKING?”
• Body piercing—51% and it’s not just
earlobes
The tattoo craze…
• Guys, out there, and everywhere…more
aggressive with their tattoos…
• Gals, are a bit more subtle…
The biggest MISCONCEPTION: Looking
like an adult means they act like an
adult…
• Even though they may “look like adults”
adolescents find it more difficult to:
Think before acting…
• Interrupt an action under way—stop speeding,
for example
• Back to the prefontal lobe that underlies
planning and voluntary behavior
• The teenager freezes and screams (the limbic
system--emotions)
• The adult brakes hard and steers out of the way
(the prefrontal cortex)
In real life, adolescents find it more
difficult to:
• Choose between safer and riskier alternatives
• Difficulty resisting peer pressure
• It’s that prefrontal cortex again—they’re using it
somewhat, but it’s overtaxed…throw in peer
pressure…”Aw c’mon, just once…” the stressful situation
on an already taxed prefrontal lobe may give in to better
judgment--
Leading to unprotected sex…
• “It take many nail to build crib; only one
screw to fill it.”
Adolescents find it more difficult to:
• Resist peer pressure
• Binge-drinking
• And, drinking impairs judgment even
further…
Digression: An interesting note on
pre-natal programming…
• In the womb…ETOH abuse by mom is the
single most important variable for an
adolescent to begin drinking
• Add peer pressure during the teenage years and
drinking can become a huge problem
• Fetal alcohol syndrome remains the number one
cause of mental retardation in the U.S.
• IQ-68; where does that get you?
STDs are also the result of
unprotected sex
HPV as an STD leads to:
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Cervical cancer
Penile cancer
Anal cancer
Vulvar cancer
Pharyngeal cancer
PUBLIC SERVICE ANNOUNCEMENT:
Consider the HPV vaccine! Gardasil
Do condoms protect? LATEX, yes.
• Are condoms 100% effective? NO
• But, they are better than NO protection at
all
The “natural feel” condoms are
worthless against STDs…
• “You wanna do WHAT with my intestines?”
By the way…does circumcision
protect against STDs?
P.S.
• The “Just Say NO”
approach is “Just
NOT working”
either…
• 1 out of every 4
adolescents has an
STD…yikes…
A second circuit is “learning” during
puberty…
• Links the prefrontal cortex to the midbrain
reward system, where addictive drugs and
romantic love exert their powers
• And without “Mom”…
• This is when you REALLY need MOM to
say NO, NO, NO…
This is the “dopamine” circuit
• Dopamine system of rewards is
developing during adolescence
• Who put the “dope” in dopamine?
• Dopamine is responsible for the “high”—
”woohoo! this feels good…let’s do it again”
feeling! The “I’m in love and it’s the real
thing” feeling…
And hormones are kicking in …
• Estrogen—powerful, in control—
“diamonds” are not a girl’s best friend—
estrogen is…
• Progesterone—powerful sister to
estrogen, but can make you awfully cranky
(think PMDD)
• E and P increase sensitivity to stress—
girls react more to relationship stress—
need to be “in” and liked
• 1st 2 weeks of menstrual cycle—clear
thinking, brain is sharper, personality
great; day 12 = peak mental performance
(take AP Biology exams, win arguments w/
mom or their teachers; talk parents into
going to a party)
• Last week of cycle—increased irritability,
less focused, changes in stress sensitivity,
fly of the handle, negative, depressed,
suicidal thoughts, “crying over dog food
commercials”—temporary insanity
(PMDD)
Other hormones are also kicking in
at puberty…
• Oxytocin—nurturing, earth momma,
cuddly (intimacy), monogamy (in other
mammals such as prairie voles)—talking,
gossiping, socializing, flirting (E activates O)
• Androstenedione—the mother of
testosterone in the ovaries; gives you a bit
of sassiness; energy, zip to your doo dah;
Let’s get back to the dopamine circuit.
Who put the “dope” in dopamine?
• Adolescents become addicted to nicotine
and alcohol faster and with lower doses
• Teenagers and adults process reward
differently
• Adolescents are hypersensitive to the
value of experiences
The earlier you start…
• More and more
evidence points to
“when” you start
addictive behaviors
and the risk of lifelong
addictions
• Ebers papyrus—
opium was used as a
remedy for a colicky
child
Early exposure to drugs and
alcohol…
• Robert Downey, Sr. gave Jr. drugs and
marijuana at age 6—thinking it was “cute”…
• “I’m allergic to alcohol and drugs—I break out in
handcuffs. –Robert Downey, Jr.
Even more scary…Decades long
addictions
• Of the more than 75 million baby boomers who
“became of age” in the ’60s and ’70s, millions
experimented with drugs during their
impressionable teenage years
• 1.75 million over 50 who are addicted to drugs
• By 2020 an estimated 4.4 million will be seeking
help for heroin or cocaine addictions
• Ad hoc longitudinal study of 40 years
Teenage girls and smoking
• Smoking hits the brain dopamine reward
system in 7-9 seconds
• Why do teenage girls start smoking?
• Peer pressure
• Weight issues
• Mood elevation
• How can we get them to stop?
• Accelerated aging angle?
Prescription drug abuse and kids
• Oxycontin—since 1992 the number of 12-to17- year olds
abusing controlled prescription drugs has tripled (5.5% of
all high school seniors)
• Prescriptions written for controlled substances have
increased more than 150 percent
• 80 oxycontin tablets for a tonsillectomy??
• Oxycontin abuse outpaces marijuana abuse (the devil
weed) by a factor of 2
By the way…
• the White House and drug “CZAR” still
consider marijuana as the “gateway”
drug…
• Even tho’ our problems with prescription
drug abuse and methamphetamine are
escalating out of control
Methamphetamine and pleasure
• Bennies, crank, ice, zip, glass, crystal,
crystal meth, poor man’s crack
• Approximately 10% of all people who use
ETOH become addicted vs. 98% of people
who use meth
• Methamphetamine and sexual function-increased performance and endurance
Why aren’t kids addicted to…?
Bottom line…
• Parents should be parents
• Teachers can be primary role models and help
to provide the “pre-frontal” cortex checks and
balances
• Kids need the word NO in their lives
• Don’t drink with your kids; don’t smoke dope with
your kids; teach abstinence but at the same time
teach safe sex
• You are not their best friend, don’t act like one
• Most of all…
Last word to the wise parent:
Some things will never change.
“Children today are tyrants. They contradict
their parents, gobble their food, and
tyrannize their teachers.”
--Socrates (470-399 B.C.)
Thank you.
• Barb Bancroft, RN,
MSN, PNP
• Chicago, IL
• [email protected]
• www.barbbancroft.com