Download The Teenage Brain - Welcome to Senior Biology

The Adolescent Brain
Bethany,18
“Knows”
Everything
Matt, 16,
can’t
remember
anything
Brainy Facts: What do we know
about the brain?
• Adult = 3 pounds
• 2% of our body weight but
consumes 20% of our
calories
• 70% water, it consumes
30% of the water we drink
• Unfolded it would
measure 2 ft x 2 ft.
• composed of a trillion
cells, 100 billion neurons
Brainy Facts: Parts of the Brain
Dr. Jay Giedd,
Neuroscientist
• Neuroscientist at the
National Institute of
Health, Chief of brain
imaging in the child
psychiatry branch
• Used MRI to scan the
brains of nearly 1000
healthy children ages
3-18.
• Between ages of birth2 and 9-10=
tremendous growth of
neurons
• Ages 2-3 and 11+=
massive pruning
• Teenagers are more
like toddlers than
adults in brain growth
During adolescence…
use it or lose it
Used connections will
flourish, unused will
be pruned and die.
•Fewer but faster
connections
http://www.sfn.org/index.cfm?pagename=brainBriefings_Adolescent_brain
The CEO of the Brain
• The frontal lobes:
executive decisions
and moral/ethical
control
• Development
continues from back
to front through
early 20’s
• “It’s sort of unfair to
expect teens to have
adult levels of
organizational skills
or decision-making
before their brains
are finished being
built.”- Dr. Giedd
Frontal Lobe
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•
•
•
Problem solving
Judgment
Inhibition of behavior
Planning
Self-monitoring
Personality
Emotions
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•
•
•
•
•
•
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Organization
Attention
Concentration
Mental flexibility
Speaking
Awareness of abilities
Self-control
“do the right thing”
Misread signals
Don’t believe everything they tell
you…..
• Teens relied on the
amygdala, associated
with emotion and gut
reactions
• MRI tests: Teens see
anger when it was
not intended
• Teens can be
irrational and overly
emotional
What about Intelligence?
• Intelligence and emotional
maturity do not develop in the
same way.
• Let’s look at a teenage genius…
During adolescence…
period of high risk
• Drugs and alcohol can
alter normal
development of the brain
• Teens who drink are
exposing their brains to
the toxic effects of
alcohol at a critical time
of brain development,
approx. 10% memory
loss
• Hormonal rush of
testosterone and estrogen
causing chemical changes
Image from Susan Tapert, PhD, University of California, San Diego
http://www.sfn.org/skins/main/images/brainbriefings/bb_Oct2002_large.gif
.
What about adolescence and
ADD/ADHD?
• Impulsive ADHD kids will often get into trouble
• The inattentive ADD kids tend to be non-compliant,
have trouble remember the things, will feel “stupid”
despite a above average or high intelligence
• “ In clinical studies, researchers confirmed that teens
with ADHD were twice as likely to have abused alcohol
within the past 6 months. They also found that teens
with ADHD were likely to abuse drugs and three times
more likely to abuse drugs other than marijuana.”
WebMD.com
• ADHD teenagers are 400% more likely to have an
automobile accident
Catching ZZZZZZs
• They need 9 ¼ hrs…
• They get…6-7….!
• The biological clock
shifts in the teen
years by up to 2
hours
Sleep deprivation can have
a major negative effect
on learning and
memory!
TV’s, computer monitors,
and cell phones can keep
adolescents from getting
enough deep sleep;
remove them from their
rooms!
How does it help the TEEN to
know this?
• Understand
themselves and their
behavior
• Allow adults around
them to guide them
• What they do in the
next 8 years makes a
difference for the rest
of their lives!