>> HI, I'M JOAN CARTAN-HANSEN.

WELCOME TO THE D4K WEB ONLY
PROGRAM.

ALSO WELCOME TO THE DISCOVERY
CENTER OF IDAHO AND THE BODIES

REVEALED EXHIBIT.

JOINING ME TO ANSWER QUESTIONS
ABOUT THE NERVOUS CYSYSTEM, DR.

MARY RIVER FROM SAINT ALPHONSUS
HOSPITAL.

LET'S GO TO THE QUESTIONS.

>> MY NAME IS KENDAUL.

VALLEY VIEW ELEMENTARY SCHOOL.

WHAT ARE THE SECTIONS IN THE
BRAIN?

>> THERE IS A RIGHT SIDE AND A
LEFT SIDE IN THE BRAIN.

AND THERE IS -- THERE ARE
FRONTAL LOBES AND THERE ARE

PARIETAL LOBES, TEMPORAL AND
OCCIPITAL LOBES AND EACH HAS A

FUNCTION.

FRONTAL LOBE FUNCTION,
INITIATION OF ACTIVITY AND

BLOCKING ACTIVITY THAT ONE
SHOULDN'T DO.

THE TEMPORAL LOBES, WHERE
HEARING IS INTERPRETED AND

WHERE SOME OF SPEECH COMES FROM
ON THE LEFT SIDE OF THE BRAIN

FOR MOST PEOPLE.

THE PARIETAL LOBES ARE MORE
INVOLVED WITH LOCALIZATION,

WHERE THINGS ARE, ARTISTIC
TENDENCIES ON RIGHT SIDE OF THE

BRAIN FOR MOST PEOPLE.

OCCIPITAL LOBES WHICH ARE VERY
FAR AWAY FROM THE -- WHERE THE

IEBLS ARE, OCCIPITAL LOBES
WHERE VISION IS INTERPRETED.

>> HOW LONG DOES A NERVE TAKE
TO SEND A MESSAGE TO YOUR

BRAIN?

>> WELL, THERE ARE SLOW NERVES
AND THERE ARE FASTENER OFS AND

THE VARIANCE IS BETWEEN TWO
MILES AN HOUR, LIKE SLOW

WALKING, VERSUS 200 MILES AN
HOUR LIKE A REALLY FAST CAR.

>> MY QUESTION IS, HOW DOES THE
NERVE SYSTEM TRAVEL SO FAST, IS

IT ELECTRICITY?

>> IT IS A KIND OF ELECTRICITY.

THE NERVES THEMSELVES ARE LIKE
ELECTRICAL CORDS.

THERE IS AN AXON IN THE CENTER
WHICH IS LIKE THE WIRE AND A

COATING AROUND THE WIRE THAT IS
LIKE THE PLASTIC ON AN

ELECTRICAL CORD.

AND SOME NERVES HAVE -- ARE
BIGGER AND THICKER.

THEY HAVE MORE INSULATION AND
THEY CAN ACTUALLY CONDUCT THE

MESSAGE OR THE ELECTRICITY A
LOT FASTER THAN THE SMALLER,

SKINNIER NERVES.

IT IS A LOT LIKE ELECTRICITY.

>> I GO TO WEST MIDDLE SCHOOL.

I HAVE A QUESTION ON HOW MANY
NERVES ARE THERE IN THE HUMAN

NERVOUS SYSTEM?

>> GRACE, I THINK THAT THE
THOUGHT IS THAT THERE ARE ABOUT

7 TRILLION, WHICH WOULD BE
7,000 BILLION.

THAT IS A LOT.

>> LAURA WOULD LIKE TO KNOW,
HOW DOES YOUR BRAIN HOLD SO

MUCH KNOWLEDGE?

>> WELL, IF YOU THINK ABOUT IT,
THE BRAIN IS -- THE BRAIN IS SO

LARGE, IT HAS A LOT OF STORAGE
SPACE IN IT.

AND WHEN YOU ARE BORN, THERE IS
ALMOST NOTHING THERE, SO YOU

GET TO START LAYING DOWN
MEMORIES AND FORMING MEMORIES

AND THEN AS YOU GET OLDER, IT
DOES GET A LITTLE HARDER TO

LEARN NEW MATERIAL.

BUT YOU ARE BORN WITH AN AWFUL
LOT OF STORAGE SPACE.

>> HI, MY NAME IS SOPHIE.

MY QUESTION IS WHAT ARE THE
NERVES MADE OUT OF?

>> SOPHIE NERVES ARE MADE OF
AXONS, LIKE THE WIRE IN AN

ELECTRICAL CORD.

THERE IS AN AXON OR A WIRE,
THAT TRANSMITS THE ELECTRICITY.

AND THAT WIRE IS COVERED WITH A
COATING CALLED A MYELIN SHEATH

WHICH PROTECTS IT BUT ALSO
KEEPS THE ELECTRICITY TRAVELING

ALONG THAT WIRE OR AXON AS
OPPOSED TO LEAKING OUT.

SO, THEY'RE VERY, VERY SIMILAR
TO ELECTRICAL CORDS.

>> MY NAME IS VICTOR.

I WANT TO KNOW WHAT DO THE TWO
SIDES OF THE BRAIN DO?

>> VICTOR, MOST PEOPLE, LEFT
SIDE OF THE BRAIN IS WHERE YOUR

SPEECH CENTER IS, WHERE YOU --
IT IS FOR SPEAKING AND

UNDERSTANDING.

AND ALSO MOST PEOPLE, THE RIGHT
SIDE OF THE BRAIN IS WHERE

THINGS ARE.

SO, IF IT DOESN'T WORK, YOU GET
LOST.

>> WOULD LIKE TO KNOW CAN
NERVES AFFECT YOUR HEART?

>> THEY CAN.

THERE ARE -- THERE ARE NERVES
THAT SLOW DOWN THE HEART AND

THERE ARE NERVES THAT SPEED UP
THE HEART.

AND IF YOU'RE ANXIOUS, THEN
YOUR HEART WILL SPEED UP

BECAUSE THAT SET OF NERVES WILL
TAKE DOMINANCE.

>> HI, MY -- I WANT TO KNOW,
WHAT HAPPENS TO YOUR SPINAL

CORD WHEN YOU EAT AND DRINK?

>> WELL, WHEN YOU EAT AND
DRINK, THEN YOU PUT -- YOU HAVE

FOOD AND YOU'VE GOT LIQUID IN
YOUR STOMACH AND THE STOMACH

SENDS A SIGNAL TO THE HEAD OR
TO THE BRAIN AND THEN THE BRAIN

SENDS SIGNIFICANT UNTILS DOWN
AND REROUTES BLOOD SUPPLY.

YOU SEND BLOOD TO YOUR STOMACH
TO SMOOSH UP THE FOOD AND

DIGEST IT AND YOU SHUNT BLOOD
AWAY FROM THE MUSCLES, WHICH IS

WHY YOU WOULD SUPPOSABLY GET A
CRAMP IF YOU WENT SWIMMING

AFTER YOU ATE.

IT IS TO ROUTE THE BLOOD WHERE
IT IS SUPPOSED TO GO.

NERVOUS SYSTEM IS INVOLVED IN
THAT.

IN BABIES, YOU FEED THEM,
DILATE THEIR STOMACHS, THEY

EMPTY THE OTHER END AND THE
SPINAL CORD AND BRAIN ALL

INVOLVED IN THAT.

>> HOW DOES YOUR BRAIN CONTROL
YOUR BODY?

>> PROBABLY THERE ARE A LOT OF
DIFFERENT ANSWERS TO THAT.

BUT ESSENTIALLY HOW IT WOULD
WORK, IF YOU WANTED TO MOVE

YOUR FINGER, YOU WOULD THINK
THE THOUGHT AND THEN THE

THOUGHT WOULD BE TRANSMITTED
DOWN IN AXON OR NERVE TO THE

SPINAL CORD, AND THEN IN THE
SPINAL CORD, IT WOULD SYNAPSE

OR CONNECT WITH A NERVE THAT
GOES OUT TO THE MUSCLE THAT

THEN MAKES THE MUSCLE MOVE.

SO IT IS SEVERAL DIFFERENT
NERVES INVOLVED, THE THOUGHT

TRANSMITS TO THE ELECTRICITY
THAT THEN STIMULATES THE

MUSCLE.

>> MY QUESTION IS DO MY NERVES
CREATE ENERGY?

>> THE NERVOUS SYSTEM DOESN'T
CREATE ENERGY.

THERE ARE LITTLE -- SOME PEOPLE
ARE MORE ENERGETIC BECAUSE OF

THE WAY THEIR BRAINS ARE WIRED.

>> DOCTOR, WE HAVE RUN OUT OF
TIME.

THANK YOU FOR BEING HERE.

WE APPRECIATE YOU JOINING US.

>> YOU ARE VERY WELCOME.

>> THANK YOU TO THE FOLKS -- IF
YOU WANT TO LEARN MORE ABOUT

THE NERVOUS SYSTEM, CHECK OUT
THE NERVOUS SYSTEM AREA ON THE

D4K WEB SITE, FACTS, LINKS,
GAMES, NERVOUS SYSTEM BROADCAST

SHOW AND LOTS MORE.

CHECK OUT THE BLOG FOR THE
LATEST SCIENCE NEWS FOR KIDS.

THANK YOU FOR JOINING US FOR