>>> WHAT ARE YOU DOING?

>> THINKING.

>> WHAT ARE YOU THINKING ABOUT?

>> THINKING.

>> IF YOU'RE THINKING ABOUT THINKING YOU'RE USING YOUR BRAIN.

IF YOU DO ANYTHING YOU'RE USING YOUR BRAIN.

DO YOU HAVE A QUESTION ABOUT THE BRAIN?

SCIENTISTS ARE STANDING BY TO ANSWER YOUR QUESTIONS.

STAY TUNED.

"D4K" IS NEXT.

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

WELCOME TO "D4K."

THE BRAIN.

IT'S THE MOST IMPORTANT ORGAN IN YOUR BODY BECAUSE IT CONTROLS EVERYTHING THAT YOU DO.

BEFORE WE GO TO THE STUDIO TO ANSWER YOUR QUESTIONS ABOUT THE BRAIN, LET'S FIND OUT MORE.

THE BRAIN WEIGHS ABOUT THREE POUNDS.

IT'S MADE UP OF 100 BILLION NERVE CELLS OR NEURONS.

ELECTRICAL IMPULSES PASS FROM CELL-TO-CELL.

MESSAGES GO OUT OF YOUR BRAIN, DOWN YOUR SPINAL CORD, AND OUT TO YOUR BODY.

AND THEN BACK AGAIN, ALL IN AN INSTANT.

THE BRAIN, THE SPINAL CORD, AND ALL THOSE NERVES MAKE UP THE NERVOUS SYSTEM.

IT'S YOUR BODY'S INFORMATION SYSTEM.

>> SCIENTISTS SAY THERE'S ENOUGH ELECTRICITY FROM ALL THOSE MESSAGES IN YOUR BRAIN AND BODY TO TURN ON THE LIGHT IN THE REFRIGERATOR.

>> THE BRAIN IS MADE UP OF SEVERAL PARTS.

THERE'S THE BRAIN STEM.

IT CONTROLS YOUR BODY'S BASIC AUTOMATIC FUNCTIONS LIKE BREATHE CAN.

THERE'S THE CEREBELLUM, WHICH CONTROLS THINGS LIKE MOVEMENT, YOUR PHYSICAL SKILLS.

AND THEN THERE'S THE LIMBIC SYSTEM.

THERE ARE GLANDS LIKE THE PITUITARY AND THE HYPOTHALAMUS.

THEY WORK WITH THE BRAIN STEM TO CONTROL BODY TEMPERATURE, GROWTH, AND BLOOD PRESSURE.

AND THEN THERE'S THE CEREBRUM.

THAT'S THE THINKING, CREATIVE PART OF YOUR BRAIN.

IT'S ALSO THE BIGGEST PART OF YOUR BRAIN.

ALONG WITH ITS THIN COVERING, THE CORTEX, IT'S THE PART OF THE BRAIN THAT GOVERNS VOLUNTARY MOVEMENTS.

IT'S WHERE YOU THINK, WHERE YOU PERCEIVE OR SENSE THINGS.

AND BECAUSE OF YOUR CORTEX, YOU CAN UNDERSTAND, REMEMBER, COMMUNICATE, AND CREATE.

THE BRAIN HASS TWO SIDES.

EACH CONTROLS THE OPPOSITE SIDE OF THE BODY.

EACH SIDE ALSO CONTROLS CERTAIN SKILLS.

THE RIGHT SIDE OF YOUR BRAIN CONTROLS MUSIC, AND ART.

THE CREATIVE STUFF.

AND THE LEFT SIDE HANDLES NUMBERS AND WORDS AND PROBLEM SOLVING.

AND THERE'S A BAND OF CELLS BETWEEN THE TWO PARTS OR HEMISPHERES OF THE BRAIN SO THE LEFT SIDE KNOWS WHAT THE RIGHT SIDE IS DOING.

>> THE HUMAN BRAIN IS SO SOFT, YOU COULD CUT IT WITH A BUTTER KNIFE.

THAT'S WHY YOU SHOULD WEAR YOUR HELMET WHEN YOU RIDE YOUR BIKE.

YOU NEED TO PROTECT YOUR BRAIN.

>> YOUR BRAIN IS BODY ALSO PUT OUT CHEMICALS CALLED HORMONES OR NEUROTRANSMITTERS.

OR MONIES HELP REGULATE 84 BODY'S GROWTH, HELP YOU MATURE, MAINTAIN YOUR DIGESTION, EVEN TELL YOU WHEN TO SLEEP.

NEUROTRANSMITTERS SEND MESSAGES BETWEEN CELLS.

SOME TELL YOUR HEART TO BEAT, OR YOUR LUNGS TO BREATHE.

WHILE OTHERS HELP REGULATE YOUR MOOD, WHETHER YOU'RE HAPPY OR SAD.

THESE CHEMICALS PLAY A PART IN HOW YOU REMEMBER THINGS.

WHY YOU DREAM.

WHO YOU ARE.

YOUR THOUGHTS AND YOUR FEELINGS, YOUR BREATHING AND YOUR GROWING, ARE ALL CONTROLLED BY YOUR BRAIN.

YOUR BRAIN CONTINUES TO DEVELOP EVEN AFTER YOU'RE BORN AND CONTINUES TO GROW AND CHANGE, EVEN AS AN ADULT.

YOUR BRAIN IS WHAT MAKES YOU, YOU.

AND JOINING ME NOW TO ANSWER YOUR QUESTIONS ABOUT THE BRAIN ARE DR.

DAVID BETTIS, A PEDIATRIC NEUROLOGIST, AND DR.

MIKAELA SEBREE, A PEDIATRIC NEUROPSYCHOLOGIST.

THANK YOU BOTH FOR BEING HERE.

AND OF COURSE WE WANT TO HEAR FROM YOU.

GIVE US A CALL AT 1-800-973-9800 OR EMAIL US AT D4K@IDAHOPTV.ORG.

AND REMEMBER, WHEN YOU SEND IN QUESTIONS, YOU AND YOUR CLASS WILL HAVE A CHANCE TO WIN A DVD AND OTHER PRIZES.

LET'S GO TO OUR FIRST ROUND OF QUESTIONS AT RIVERSIDE ELEMENTARY IN BOISE, HOW MANY CELLS ARE THERE IN THE BRAIN?

>> THERE ARE ABOUT 100 BILLION NERVE CELLS IN ONE HUMAN BRAIN.

TO PUT THAT IN PERSPECTIVE, THERE ARE 500 MILLION USERS OF FACEBOOK, 300 MILLION PEOPLE IN THE UNITED STATES.

THERE'S 100 TIMES MORE CELLS IN ONE HUMAN BRAIN.

IT'S A BIG NUMBER.

>>> TYLER WOULD LIKE TO KNOW HOW BIG IS YOUR BRAIN?

>> FULL-SIZE BRAIN WEIGHS ABOUT THREE POUNDS, FULL SIZE.

>> HOW FAR OFF IS THAT?

>> UM, PROBABLY NOT TOO FAR OFF FROM WHAT'S INSIDE YOUR SKULL.

>> OK.

WE'VE GOT A QUESTION FROM MRS.

SCHULTZ CLASS, WHY IS YOUR BRAIN PLACED IN YOUR SKULL AND ALSO FROM ONE OF HER CLASSMATES, DAKOTA WANTS TO KNOW, WHY CAN'T THE BRAIN BE LOCATED SOMEWHERE ELSE IN THE BODY.

>> THAT IS A VERY, VERY GOOD QUESTION.

IF YOU THINK ABOUT WHAT THE BRAIN DOES, IT IS THE COMMAND CENTER FOR THE BRAIN, THE INFORMATION CENTER, AND IF I WAS DESIGNING THE HUMAN BODY, I WOULD PUT THE BRAIN SOMEPLACE THAT MADE IT EASY TO DO ITS JOB.

AND IF YOU THINK ABOUT IT, THE HEAD IS A PERFECT PLACE.

IT'S ON TOP, WE HAVE A NECK THAT CAN SWIVEL SO WE CAN TURN OUR HEAD AND SEE THINGS IN DIFFERENT PLACES.

AND STILL THE BRAIN IS WELL PROTECTED BY THE SKULL.

AND THE BRAIN IS LOCATED OUTSIDE OF THE TOP OF THE BODY IN SOME OTHER ANIMAL SPECIES, BUT THE BRAIN IS LOCATED HERE FOR A VERY GOOD REASON.

>> LET'S GO TO OUR FIRST PHONE CALLER, MEGAN, GO AHEAD.

>> Caller: MY QUESTION IS, WHY AND HOW DOES ONE SIDE OF YOUR BRAIN CONTROL THE OTHER SIDE OF YOUR BODY?

>> THAT LEFT-RIGHT, RIGHT-LEFT.

>> THAT'S A VERY GOOD QUESTION.

MY ANSWER IS, I DON'T KNOW.

WHAT WE DO KNOW IS SOME TIME BACK IN EVOLUTION, THE RIGHT SIDE PATHWAY TO THE BRAIN CROSSED OVER, SO THAT THE RIGHT SIDE OF THE BRAIN CONTROLS THE LEFT SIDE OF THE BODY, AND THE LEFT SIDE OF THE BRAIN FOR THE MOST PART CONTROLS THE RIGHT SIDE OF THE BODY.

WHY THAT HAPPENED, PEOPLE ARE STILL TRYING TO UNDERSTAND.

WE KNOW THAT IT DID HAPPEN.

ANOTHER INTERESTING FACT IS THERE IS ONE PART OF THE BRAIN, THE CEREBELLUM, WHICH CONTROLS BALANCE AND COORDINATION, THIS PART OF THE BRAIN IS VERY BIG IN CATS WHO ARE SO NIP ONLY THEIR FEET.

THE PATHWAYS TO THE CEREBRUM CROSS OVER TWICE, SO THE RIGHT SIDE OF THE CEREBRUM CONTROLS THE RIGHT SIDE OF THE BODY.

SO IT'S VERY, VERY COMPLICATED.

GOOD QUESTION.

>> ARE THERE ANY PEOPLE WHERE THE RIGHT SIDE CONTROLS THE RIGHT SIDE?

OR EVERYBODY CROSSES -- >> IN ATYPICAL ORGANIZATIONS, SO WHEN THE BRAIN IS DEVELOPING, THERE'S SORT OF TYPICAL ORGANIZATION, SO IT'S THE MAJORITY OF PEOPLE, THE LEFT SIDE CONTROLS THE RIGHT SIDE OF THE BODY.

BUT EVERY ONCE IN A WHILE IF A CHILD, FOR EXAMPLE, HAS A STROKE WHILE THEY'RE STILL IN THEIR MOTHER'S TUMMY, SOMETIMES THE BRAIN ORGANIZES IN A WAY WE CALL ATYPICAL, SO THE LEFT SIDE OF THE BRAIN CAN STILL CONTROL BOTH THE LEFT SIDE AND THE RIGHT SIDE OF THE BODY.

>> THIS IS A QUESTION FROM JAMIE WHO IS HOME SCHOOLED.

WHY ARE SOME PEOPLE AMBIDEXTROUS?

WHICH MEANS YOU CAN WRITE BOTH WITH YOUR LEFT AND RIGHT HAND.

>> THAT MEANS INSTEAD OF BEING RIGHT-HANDED OR LEFT-HANDED, YOU'RE EQUAL WITH BOTH HANDS.

AND THAT'S A VERY GOOD QUESTION.

THE VAST MAJORITY OF PEOPLE ARE RIGHT-HANDED, 90%.

ABOUT 10% OF PEOPLE ARE LEFT-HANDED, BUT SOME PEOPLE ARE TRULY AMBIDEXTROUS.

AND I DON'T KNOW EXACTLY WHY THAT IS, SOME PEOPLE JUST HAPPEN -- IT HAPPENS NATURALLY.

BUT THERE ARE OTHER PEOPLE WHO HAVE AN INJURY TO ONE SIDE, AND IF YOU BREAK YOUR RIGHT ARM AND YOU'RE RIGHT-HANDED, THERE ARE PEOPLE WHO CAN PICK UP A LOT OF TASKS WITH THE LEFT HAND.

I WISH I WAS AMBIDEXTROUS, BECAUSE THERE'S SOME SPORTS THAT WOULD BE A WIG ADVANTAGE.

-- A BIG ADVANTAGE.

BUT I THROW WITH MY RIGHT HAND AND WITH MY LEFT HAND IT DOESN'T WORK NEARLY AS WELL.

>> ME TOO.

WE HAVE SOME QUESTIONS ON TAPE.

WE LET'S GO TO THE FIRST ONE FROM CLAIRE.

>> HI, MY NAME IS CLAIRE, I GO TO LONGFELLOW ELEMENTARY, AND HOW DOES THE BRAIN THINK OF ALL THESE THOUGHTS?

>> THAT'S A GREAT QUESTION.

THE BRAIN IS REALLY, REALLY ALMOST MAGICAL IN WHAT IT'S ABLE TO DO.

THE BRAIN IS ABLE TO THINK FAST, BASICALLY THROUGH THE RELIEF OF NEUROTRANSMITTERS AND THE CONNECTIONS IN THE BRAIN THAT ALLOW US TO THINK ABOUT THINGS AND TO DO THE SINCE THAT -- THINGS THAT WE'RE ABLE TO DO.

>> IS IT BASICALLY CHEMICALS THAT CREATE THOUGHTS?

>> I WOULD SAY YES.

IT'S BASICALLY CHEMICALS THAT CREATE THE THOUGHTS, BUT IT'S ALSO THE WAY OUR BRAIN IS ORGANIZED OR THE NETWORKS ARE ORGANIZED.

THAT ALLOW US TO HAVE THE THOUGHTS THAT WE HAVE.

>> QUESTION FROM JOSHUA, WHO IS HOME SCHOOLED, HOW DOES YOUR BRAIN CONTROL YOUR BODY?

>> VERY GOOD QUESTION.

THE BRAIN HAS MANY FUNCTIONS.

AND CONTROL OF THE BODY SPECIFICALLY MOVEMENT S. ONE OF THE MORE IMPORTANT FUNCTIONS.

SO THERE IS A SPECIFIC PART OF THE BRAIN CALLED THE MOTOR CORTEX, THAT ALLOWS US TO CONTROL BODY MOVEMENTS.

AND WHEN I RAISE MY LEFT HAND, MY RIGHT MOTOR CORTEX IS SENDING A SIGNAL DOWN THROUGH MY SPINAL CORD TO THE MUSCLES IN MY ARM SAYING, RAISE YOUR LEFT ARM, WIGGLE YOUR FINGERS.

AND BYE VICE VERSA ON THIS SIDE.

SO THERE'S A COMPLEX SET OF PATHWAYS THAT INITIATE MOVEMENT IMPULSES AND CONTROL OUR BODY, AND THERE'S ANOTHER WHOLE SET OF PATHWAYS, SENSATION THAT ALLOW THE FEELINGS OF TOUCH AND COLD AND PAIN TO TRAVEL UP OUR BODY THROUGH A DIFFERENT SET OF NERVES TO THE SENSORY CORTEX.

SO IT'S A VERY INTERESTING AND COMPLICATED SYSTEM.

>> MRS.

HUDSON, RANDY IN MRS.

HUDSON'S CLASS ASKS A SIMILAR QUESTION, HOW DOES THE BRAIN STORE THOUGHTS?

HOW DO WE STORE MEMORIES?

>> I THINK SCIENTISTS ARE STILL TRYING TO FIGURE OUT EXACTLY HOW THAT PROCESS HAPPENS.

BUT THERE'S A REALLY IMPORTANT PART OF OUR BRAIN THAT'S CALLED THE -- IT'S IN THE LIMBIC SYSTEM, AND IT HELPS STORE AND CREATE NEW MEMORIES.

SO IF PEOPLE HAVE DAMAGE TO IT, IT'S HARD FOR THEM TO LEARN NEW THINGS.

BUT INFORMATION IS GENERALLY STORED IN A NETWORK, IT'S NOT LIKE WE HAVE ONE PART OF THE BRAIN WHERE EVERY MEMORY IS STORED, THEY'RE ACTUALLY STORED THROUGHOUT THE BRAIN.

BUT THAT CREATES NEW LEARNING AND HELPS US CREATE NEW MEMORIES.

>> ALEX WOULD LIKE TO KNOW HOW MUCH BIGGER IS THE HUMAN BRAIN THAN A DOG'S BRAIN?

>> YOU CAN TAKE A GUESS AT HOW BIG A BRAIN IS BY LOOKING AT THE SIZE OF THE SKULL.

SO THIS IS PRETTY MUCH AN ADULT SIZE BRAIN, AND YOU CAN SEE IF I HOLD IT UP TO MY BRAIN IT WOULD PRETTY MUCH FILL THE CAVITY OF MY SKULL.

AND IF YOU LOOK AT THE SKULL OF A DOG, BEHIND THEIR EYES, THAT WOULD BE THE SIZE.

SO A DOG'S BRAIN FOR ALL SPECIES OF DOGS I KNOW WOULD BE QUITE A BIT SMALLER THAN A HUMAN BRAIN.

>> DOES THE SIZE OF YOUR BRAIN MEAN HOW INTELLIGENT A CREATURE IS?

SO BIRDS ARE SMALLER THAN CATS, SO ARE CATS SMARTER THAN BIRDS?

>> THAT'S SOMEWHAT OF A HARD QUESTION TO ANSWER.

IN HUMANS THERE ARE DIFFERENT SIZE BRAINS AND DIFFERENT LEVELS OF INTELLIGENCE OR DIFFERENT LEVELS OF SMARTNESS, BUT IN GENERAL THE BIGGER THE BRAIN THE SMARTER YOU ARE, THE MORE CAPACITY FOR ADVANCED THINKING, OR CORTICAL THINKING.

I DON'T THINK THAT ANIMALS CAN DO A LOT OF THE THINGS HUMANS CAN DO, OBVIOUSLY, THEY DON'T PAY ATTENTION THE WAY THAT WE DO, THEY DON'T HAVE LANGUAGE THE WAY THAT WE DO.

BUT IN A HUMAN, WHAT MAKES SOMEBODY SMARTER THAN THE NEXT PERSON IS ACTUALLY NOT THE SIZE OF THEIR BRAIN, BUT IT'S ACTUALLY THE AMOUNT OF CONNECTIONS THAT THEY HAVE IN THE BRAIN.

>> HOW DO YOU CREATE THOSE CONNECTIONS?

>> FROM NEW LEARNING.

SO IT'S FROM LEARNING.

>> DREW IN BOISE.

DREW?

>> Caller: HI.

I JUST WANT TO KNOW HOW I -- HOW YOUR BRAIN DOES DREAMS AND HOW YOU VISUALIZE IT.

>> HOW DOES YOUR BRAIN MAKE A DREAM?

>> THAT'S A VERY GOOD QUESTION.

AND IT REALLY GETS TO ONE OF THE BEST THINGS ABOUT THE HUMAN BRAIN.

WHICH IS, WE DON'T UNDERSTAND A LOT OF THINGS ABOUT IT.

I READ SOMEWHERE THAT WE KNOW MORE ABOUT STARS THAT ARE BILLIONS OF MILES AWAY FROM THE EARTH THAN WE KNOW ABOUT THE WORKING OF THE HUMAN BRAIN, WHICH IS ONE OF THE GREAT MYSTERIES IN THE UNIVERSE.

AND I AM ONE OF THE PEOPLE WHO THINKS THE HUMAN BRAIN IS THE MOST COMPLEX PHYSICAL THING IN OUR UNIVERSE.

IT'S THAT POORLY UNDERSTOOD.

SO HOW THE BRAIN GENERATES DREAMS IS THE SUBJECT OF A LOT OF ONGOING RESEARCH AND SPECULATION THROUGHOUT HISTORY.

IT'S A PHENOMENON ALMOST EVERYONE EXPERIENCES, AND WHEN I HAVE A DREAM, I THINK ABOUT IT THE NEXT DAY AND I THINK, WHERE DID THAT COME FROM?

[LAUGHTER] WHY WAS I ABLE TO FLY JUST BY FLAPPING MY WINGS?

ONE TIME I WAS BASKETBALL PLAYER, I COULD JUMP FOUR FEET HIGHER THAN ANYONE ELSE, IT WAS A VERY PLEASANT DREAM.

BUT WE DON'T REALLY UNDERSTAND THAT, AND WE NEED BRIGHT, YOUNG PEOPLE TO DECIDE THEY'RE GO TO GO INTO BRAIN RESEARCH AND HELP US FIND OUT.

>> LAUREN FROM DALTON ELEMENTARY WOULD LIKE TO KNOW, HOW DOES THE BRAIN STEM HELP THE BRAIN THINK, OR DOES IT DO SOMETHING ELSE?

>> THE BRAIN STEM IS ACTUALLY NOT MUCH OF A THINKER, OR THE THINKING PART OF THE BRAIN.

IT'S REALLY THE PART OF THE BRAIN THAT TELLS OUR BODY TO BREATHE, IT TELLS OUR HEART TO BEAT, SO IT'S VERY, VERY IMPORTANT FOR ALL OF THE VITAL LIFE FUNCTIONS, BUT IT DOESN'T REALLY PLAY A ROLE IN THOUGHT, NECESSARILY.

>> THIS QUESTION CAME FROM CORINNE IN IDAHO FALLS, WHICH IS THE SCHOOL I WENT TO, SO THANK YOU FOR CALLING N MY SISTER HAS A SMOOTH BRAIN AND CAN'T WALK Y DO WE NEED WRINKLES IN OUR BRAIN?

>> VERY GOOD QUESTION.

SO IF YOU LOOK AT THIS BRAIN MODEL, YOU'LL SEE THAT IT HAS LOTS AND LOTS OF WRINKLES, AND IN A SENSE IT LOOKS LIKE A BAG OF WORMS.

THIS HAS TO DO WITH THE COMPLEXITY OF THE HUMAN BRAIN.

THESE INFOLDINGS ALLOW THERE TO BE A LOT MORE SURFACE AREA OF THE MOST IMPORTANT PART OF THE BRAIN IN SOME WAYS THE CORTEX, OR THE SURFACE OF THE BRAIN.

SO IF WE TOOK A HUMAN BRAIN AND WE COMPLETELY FLATTENED IT OUT, EVEN THOUGH IT'S A SIZE OF A GRAPEFRUIT, IF YOU COMPLETELY FLATTENED IT OUT IT WOULD BE THE SIZE OF A DOUBLE SECTION OF A NEWSPAPER.

SO THERE'S A LOT OF SURFACE AREA HERE, AND THAT HAS A LOT TO DO WITH THE FUNCTION OF THE BRAIN.

WHEN THE BRAIN DOES NOT FORM PROPERLY AND THOSE WRINKLES DON'T OCCUR, IT CAN REALLY AFFECT HOW THE BRAIN WORKS.

AND SO THERE ARE MEDICAL CONDITIONS WHERE THE BRAIN DOES NOT FORM PROPERLY, AND THAT'S -- THAT I'M SURE HAS SOMETHING TO DO WITH THE SISTER.

>> LAUREN FROM MRS.

WOODALL'S CLASS AND EMMA FROM MRS.

HUDSON'S CLASS HAVE A SIMILAR QUESTION.

WHY IT IS IMPORTANT TO KEEP YOUR BRAIN HEALTHY AND EXERCISE IT, AND HOW DOES THINKING MAKE YOUR BRAIN SMARTER?

>> WELL, ONE OF THE WAYS THAT WE CREATE THE NETWORKS IS THINKING THE SAME THOUGHTS.

THAT'S WHY MOST OF US ARE NOT SO SMART THAT WE CAN HEAR SOMETHING ONE TIME AND HAVE IT MEMORIZED.

THAT'S YITS IMPORTANT TO STUDY FOR OUR EXAMS AND NOT JUST CRAM BEFORE THE TEST, BECAUSE IT TAKES LOTS OF PRACTICE, IT TAKES OUR BRAIN LOTS OF PRACTICE TO LEARN ALL OF THAT INFORMATION.

IT'S ALSO ONE OF THE REASONS WE THINK THAT SLEEP IS REALLY IMPORTANT, BECAUSE SLEEP IS THE TIME THAT OUR BRAIN DOES A LOT OF CLEANING, KIND OF CLEANING UP, SO TO SPEAK.

SO IT ALLOWS THE BRAIN TO CREATE THOSE LONG-TERM MEMORIES THROUGH A CHEMICAL PROCESS, ACTUALLY.

>> DOES THE BRAIN GO HEAVIER BECAUSE IT STORES MORE?

IS YOUR THINKING AND LEARNING, DOES YOUR BRAIN GET HEAVIER?

>> NO.

THAT'S A GOOD QUESTION, BECAUSE IF I AM KEEPING A FILE SYSTEM AND I PUT MORE AND MORE PAPER IN THE FILE, IT GETS HEAVIER AND HEAVIER.

BUT THE BRAIN ACTUALLY IN THAT SENSE WORKS LIKE A COMPUTER.

AS WE ENTER INFORMATION IN THE COMPUTER, THE COMPUTER DOESN'T GET HEAVIER, IT MAKES MORE CONNECTIONS, AND HAS DIFFERENT WAYS OF RETRIEVING INFORMATION.

SO IT DOES NOT GET HEAVIER, NOR DOES IT GROW MORE CELLS.

THE MAXIMUM NUMBER OF BRAIN CELLS WE HAVE AS A HUMAN BEING OCCURS SHORTLY BEFORE WE'RE BORN, AND WE START LOSING BRAIN CELLS.

BUT WE DON'T USE ALL THE BRAIN CELLS THAT WE HAVE.

AS DR.

SEBREE SAID, IT'S IMPORTANT THAT IS THE CONNECTIONS AND HOW YOU USE IT.

EVERYONE HAS HEARD THE PHRASE "USE IT OR LOSE IT."

IF YOU ARE A BASEBALL PLAYER AND DON'T THROW FOR A LONG TIME, YOUR THROWING IS NOT AS GOOD, AND IF YOU'RE A DANCER AND IF YOU'RE NOT PRACTICING ALL THE TIME, OR PLAYING PIANO, SAME GOES FOR BRAIN FUNCTION.

THE MORE YOU USE IT, THE BETTER THE BRAIN WORKS.

INCLUDING IN OLDER PEOPLE, IT'S BEEN SHOWN THAT IT'S VERY HEALTHY FOR A BRAIN FOR ELDERLY PEOPLE TO STAY ACTIVE AND DO CROSSWORD PUZZLES, AND TALK TO OTHER PEOPLE TO KEEP THEIR BRAIN FUNCTIONING NORMALLY.

THERE'S ANOTHER ASPECT OF BRAIN HEALTH I'D LIKE TO BRING UP, WHICH IS BRAIN SAFETY.

WE'VE TALKED ABOUT HOW IMPORTANT THE BRAIN IS, AND HOW MARVELOUS AND HOW MIT MIRACULOUS IT S WELL, YOU NEED TO TAKE GOOD CARE OF YOUR BRAIN.

DR.

SEBREE SAID SLEEP, WHICH HELPS YOUR BRAIN RECHARGE.

NUTRITION, WE HAVE TO EAT HEALTHY FOOD, AND SAFETY FROM INJURY.

SO VERY IMPORTANT TO WEAR YOUR BIKE HELMET.

IT'S EVEN MORE IMPORTANT TO WEAR YOUR SEAT BELT, BECAUSE CARS GO FASTER THAN BELTS.

SO DON'T HURT YOUR BRAIN, BECAUSE ONCE THOSE CELLS ARE GONE, THEY NEVER GROW BACK.

LOTS OF OTHER CELLS IN OUR BODY WILL GROW BACK.

OUR FINGERNAILS, OUR HAIR, LOTS OF OTHER ORGANS DO, BUT BRAIN CELLS HAVE LOST THE ABILITY TO GROW BACK.

SO WE HAVE TO TAKE CARE OF THE BRAIN THAT WE HAVE.

>> KY WANTS TO KNOW, WHAT HAPPENS IF PART OF YOUR BRAIN DOESN'T WORK?

>> BOTH DR.

SEBREE AND I SPEND A LOT OF TIME WITH PATIENTS LIKE THAT.

>> YEAH, WE DO.

THAT'S A HARD QUESTION TO ANSWER, BAWT BECAUSE IT DEPENDS ON WHICH PART OF THE BRAIN ISN'T WORKING.

I TEND TO SEE A LOOT OF PEOPLE WHO HAVE PARTS OF THE BRAIN THAT AREN'T WORKING AS EFFICIENTLY OR AS EFFECTIVELY AS IT SHOULD, AND SO I SEE KIDS THAT HAVE VARIOUS LANGUAGE DISORDERS, OR PROBLEMS WITH ATTENTION, PROBLEMS FORMING NEW MEMORIES.

SO IT REALLY DEPENDS ON WHICH PART OF THE BRAIN ISN'T WORKING.

THE BRAIN STEM IS REALLY IMPORTANT, WE CAN'T REALLY LIVE IF OUR BRAIN STEM DOESN'T WORK.

BUT THE REST OF THE CORTEX, THE HIGHER PART OF THE BRAIN REALLY DEPENDS ON WHERE THE DAMAGE IS LOCATED.

>> THAT'S ONE OF THE WAYS WE LEARN ABOUT HOW THE BRAIN WORKS.

SO WHEN -- ACTUALLY WE LEARNED A LOT ABOUT THIS PARTLY FROM BRAIN INJURIES OF PEOPLE WHO WERE IN THE CIVIL WAR.

WE LEARNED FROM THAT THAT IF ONE PART OF THE BRAIN IS HURT, IT CONTROLS MOVEMENT.

ANOTHER ONE CONTROLS SENSATION, ANOTHER ONE EMOTION, ANOTHER ONE THINKING, ANOTHER ONE MEMORY, AND SO ON AND SO ON.

VERY INTERESTING SCIENCE.

>> IT'S NOT ALWAYS COMPARTMENTALIZED.

IF YOU LOSE ONE PART CAN ANOTHER PART SOMETIMES ADAPT AND PICK UP THE FLAK?

>> YES.

THAT'S A VERY COMPLICATED QUESTION TO ANSWER.

THE OLD WAY OF THINKING WAS, IT WAS VERY COMPORTMENTALLIZED, BUT IT TURNS OUT THERE ARE OTHER PARTS OF THE BRAIN THAT CAN TAKE OVER, NEW NETWORKS CAN KICK IN, AND WE'RE ACTUALLY RETHINKING OUR UNDERSTANDING OF THE POTENTIAL OF HEALING OF THE BRAIN BASED ON SOME EMERGING INFORMATION FROM SCIENTIFIC AND MEDICAL RESEARCH.

>> BUT IF YOU LOSE YOUR BRAIN STEM, YOU'RE IN BIG TROUBLE.

>> YOU'RE IN BIG TROUBLE.

>> THAT IS PART OF THE BRAIN THAT CONTROLS BREATHE SOMETHING.

>> YES.

THE BRAIN STEM IS VITAL FOR LIFE.

>> SO MAKE SURE TO WEAR YOUR HELMET AND YOUR SEAT BELT.

WHAT IS ON THE INSIDE AFTER HUMAN BRAIN?

WHAT IS IT?

IS IT TISSUE?

IS IT BLOOD?

IS -- WHAT IS ACTUALLY ON THE INSIDE?

>> THE INSIDE OF THE HUMAN BRAIN IS A FASCINATING SUBJECT.

SO THE HUMAN BRAIN IS COMPOSED MUCH THE HUNDRED BILLION NERVE CELLS, OR NEURONS WE TALKED ABOUT, PLUS THEY'RE INTERCONNECT ORDER AN AVERAGE WITH 10,000 CELLS EACH.

SO IF YOU THINK ABOUT YOUR CONNECTIONS ON FACEBOOK, 10,000 FRIENDS EACH PERSON, HASS A -- THAT'S A LOT OF CONNECTIONS.

BUT ALSO FOR THE BRAIN CELLS TO WORK, THEY'RE BATHED IN SPINAL FLUID, WHICH IS A TIGHTLY CONTROLLED FLEW THAT I'D NOURISHES BRAIN CELLS.

THERE ARE CONNECTIVE CELLS THAT KEEP THE BRAIN STRUCTURE WHERE THEY ARE, AND BRAIN CELLS TO HAVE HAVE ANA SUPPLY OF OXYGEN AND BLOOD TO SURVIVE, BECAUSE BRAIN CELLS ARE HIGHLY SPECIALIZED.

THAT'S WHY THEY CAN DO THE THINGS THEY DO.

BUT THEY DON'T STORE ANY ENERGY.

SO THEY HAVE TO HAVE A CONSTANT SUPPLY OF OXYGEN AND SUGAR TO SURVIVE, AND THAT IS THROUGH THE BLOOD SYSTEM.

>> WE HAVE ANOTHER QUESTION FROM THE DISCOVERY CENTER, THIS TIME IT'S LUCY.

>> HI, MY NAME IS LUCY, AND I GO TO FOOTHILLS SCHOOL OF ARTS AND SCIENCES.

HOW BIG DOES THE BRAIN GET?

>> HOW BIG?

>> THAT'S A VERY GOOD QUESTION, AND I THINK EVERYONE WHO SAW LUCY SAW THAT SHE WAS THINKING VERY HARD.

SO SHE'S GOT A VERY GOOD BRAIN.

SO THE BRAIN GETS ABOUT THE SIZE OF YOUR SKULL, AND ACTUALLY I'M HOLDING UP THE BRAIN HERE, THE BRAIN GROWING IS WHAT CAUSES YOUR SKULL TO GROW.

SO THE SIZE OF YOUR HEAD IS ACTUALLY DETERMINED BY BRAIN GROWTH.

>> SO AN INFANT'S BRAIN IS GROWING ALONG WITH THE REST -- .

>> IT'S GROWING INN SIZE, THOUGH NOT IN CELL NUMBER, CORRECT.

>> SO DO THE CELLS EXPAND?

>> THE CELLS DON'T EXPAND, OTHER THINGS HAPPEN FOR BRAIN DEVELOPMENT THAT AFFECT BRAIN SIZE.

BUT WE DON'T ACQUIRE NEW CELLS, THAT'S NOT THE REASON THE BRAIN GROWS IN VOLUME.

>> BEN FROM MRS.

SCHULTZ CLASS WOULD LIKE TO KNOW, HOW DOES ALZHEIMER'S AFFECT YOUR BRAIN?

>> THAT'S AN EXCELLENT QUESTION, SO ALZHEIMER'S AFFECTS YOUR BRAIN BASICALLY WHAT HAPPENS IS YOUR BRAIN STARTS TO -- IN SH YOUR BRAIN STARTS TO GET OER AND SOME OF THE CELLS BEGIN TO DIE.

THAT'S ONE OF THE THINGS THAT CAUSES OUR CELLS TO DIE, IS GETTING OLDER.

WHICH IS NOT FUN FOR ANY OF US.

I JUST HAD MY BIRTHDAY, SO IT'S DEFINITELY NOT FUN FOR ME.

BUT ALZHEIMER'S IS REALLY A TYPE OF DISEASE THAT WE CALL DEMENTIA, AND THERE ARE DIFFERENT SORT OF SUBTYPES OR CATEGORIES OF ALZHEIMER'S THAT CAN AFFECT DIFFERENT COGNITIVE FUNCTIONS OR DIFFERENT TYPES OF THINKING SKILLS.

BUT WHAT'S ESSENTIALLY HAPPENING IS THE BRAIN IS SLOWLY DETERIORATINDETERIORATING AND CAUSING WHAT WE CALL PLAQUE AND TANGLES.

SO THE NETWORKS ARE GETTING CONNECT AND THEY'RE RESULTING IN RESULTINGIN TANGLED BRANCHES, AND THAT CAUSES LOSS OF MEMORY, YOU GET LOSS EASY, YOU DON'T REMEMBER WHO PEOPLE ARE, HARD TIME PAYING ATTENTION, YOU HAVE A HARD TIME REGULATING HOW YOU FEEL, SO SOMETIMES PEOPLE ARE MORE CRANKY THAN THEY USED TO BE.

SOMETIMES THEY'RE MUCH MORE HAPPY THAN THEY USED TO BE.

>> AND I'LL DISAGREE WITH DR.

SEBREE ON THIS ONE THING.

I THINK GETTING OLDER IS GREAT.

I'VE GOTTEN OLDER -- [LAUGHTER] I CAN DRIVE A CAR, I CAN FLY AN AIRPLANE, AND I USE MY BRAIN EVERY DAY TO ACCOMPLISH NEW THINGS.

SO I THINK ALL OF THE CHILDREN IN SCHOOL SHOULD LOOK FORWARD TO GETTING OLDER.

[LAUGHTER] >> BETTER THAN THE ALTERNATIVE.

>> THAT IS BETTER THAN THE TURN TEF.

>> WE HAVE A QUESTION WE DON'T USUALLY TAKE FROM OLDER KIDS, BUT THIS IS FROM NICK WHO IS 16.

HE WANTS TO KNOW WHAT MARIJUANA DOES TO THE BRAIN.

LET'S TALK A LITTLE BIT ABOUT DRUGS.

WHAT CAN DRUGS DO?

IN THIS CASE ILLEGAL DRUGS.

>> WE TALKED ABOUT BRAIN HEALTH EARLIER.

AND WHEN YOUR BRAIN IS WORKING NORMALLY YOU FEEL SHARP, YOUR MEMORY IS WORKING WELL, DO YOU WELL ON TESTS, YOU GET GOOD GRADES IN SCHOOL, YOUR BEHAVIOR IS GOOD.

EVERYTHING IS WORKING LIKE IT SHOULD.

DRUGS AFFECT THE BRAIN IN A LOT OF DIFFERENT WAYS.

MARIJUANA SPECIFICALLY SLOWS THE BRAIN DOWN, IT ALTERS YOUR SENSE OF REALITY, IT MAKESA IT DANGEROUS FOR YOU TO DO THINGS LIKE DRIVE A CAR, SINCE WE'RE TALKING ABOUT A 16-YEAR-OLD.

AND CAN LEAD PEOPLE TO MAKE BAD DECISIONS AND GET IN SITUATIONING WHERE THEY WOULDN'T NORMALLY BE BECAUSE THEIR BRAIN IS NOT WORKING ON ALL CYLINDERS, SO TO SPEAK.

AND DRUGS CAN HAVE A VERY DANGEROUS EFFECT ON THE BRAIN, AND THAT'S ONE OF THE THINGS YOU CAN DO THAT IS VERY BAD FOR YOUR BRAIN HEALTH.

>> A QUESTION FROM -- WE HAVE A LOT OF QUESTIONABOUTS SIZE OF THE BRAIN.

HOW FAST DOES THE BRAIN TELL THE HAND TO DO SOMETHING?

IF I TOUCH SOMETHING HOT, HOW FAST IS THAT BRAIN WORK SOMETHING.

>> VERY FAST.

THIS IS ONE OF THE UNIQUE SITUATIONS WHERE THE MESSAGE DOESN'T GO ALL THE WAY FROM YOUR SPINAL CORD TO YOUR BRAIN, IT ACTUALLY JUST GOES FROM YOUR THOOND YOUR SPINAL CORD.

IT'S A REFLEX.

SO WHAT THE REFLEX DOES IS IT ALLOWS THE BRAIN TO KIND OF NOT STAY INVOLVED, BUT THE SPINAL CORD IS ACTUALLY INVOLVED.

AND SO THE MESSAGE GETS SENT TO THE SPINAL CORD, IT SAYS THIS IS HURTING ME, I NEED TO REMOVE MY HAND REALLY QUICKLY, SO THE SPINAL CORD SENDS THE MESSAGE IMMEDIATELY BACK TO THE HAND AND PULLS IT AWAY.

>> NATALIE WOULD LIKE TO KNOW, EXACTLY HOW MANY THINGS CAN YOUR BRAIN DO?

DO WE KNOW?

>> THAT'S AN EXCELLENT QUESTION.

I DON'T KNOW THE ANSWER TO THAT QUESTION.

I THINK THERE'S JUST TOO MANY THINGS OUR BRAIN, EVERY TIME WE THINK THERE'S A LIMIT AS TO WHAT OUR BRAIN CAN DO, I THINK SOMEBODY DOES IT.

>> THE LIMIT TO WHAT THE BRAIN CAN DO WE DON'T KNOW YET.

BUT WHAT WE KNOW, THE HUMAN BRAIN CAN PUT A MAN ON THE MOON, IT CAN BUILD TALL BUILDINGS, IT CAN PRODUCE TV PROGRAMS, IT CAN WRITE BOOKS.

IT CAN WRITE POETRY.

IT CAN DO -- IT CAN FALL IN LOVE.

IT CAN WIN AN OLYMPIC GOLD MEDAL.

SO IF WE MADE A LIST OF ALL THE THINGS THE BRAIN COULD DO, WE WOULD TAKE A LOT MORE TIME THAN THIS PROGRAM HAS.

>> WE'RE ALMOST OUT OF TIME.

WE HAVE A COUPLE PEOPLE ON THE PHONE, SO STAY WITH US, DON'T HANG UP, WE'LL CATCH YOU WHEN WE TAPE OUR WEB EXTRA.

SO IF YOU'RE ON THE PHONE, STAY WITH US.

I WANT TO ASK YOU QUICK BEFORE WE GO, WHY DID YOU DECIDE YOU WANTED TO LEARN ABOUT THE BRAIN?

>> YOU KNOW, FOR ME I ALMOST KIND OF STUMBLED INTO IT.

THE MORE I LEARNED ABOUT PEOPLE AND CHILDREN, THE MORE INTERESTED I BECAME IN THE BRAIN AND I JUST THINK THE BRAIN IS QUITE FRANKLY THE COOLEST THING OUT THERE, BECAUSE IT CONTROLS EVERYTHING THAT WE DO.

IT CONTROLS OUR SLEEPING, IT CONTROLS OUR EATING, IT CONTROLS OUR BREATHING.

IT CONTROLS ALL OF OUR THOUGHTS AND OUR EMOTIONS, IT'S WHAT FALLS IN LOVE.

THAT'S PRETTY MAGICAL IT'S ONE PART OF OUR BODY THAT DOES ALL OF THAT.

I THINK IT'S A PRETTY AMAZING STRUCTURE.

>> AND I AGREE.

TO ME THE BRAIN IS ENDLESSLY FASCINATING.

THERE'S SO MUCH WE DON'T UNDERSTAND, THERE'S SO MUCH MORE TO LEARN, THE MORE I LEARN ABOUT THE BRAIN THE MORE INTERESTED I GET.

AND IN SOME WAYS I LEAVE -- LIVE A BRAIN CENTRIC LIFE, SO I DON'T THINK OF SCHOOLS AS SCHOOLS, I THINK OF A SCHOOL AS A BRAIN FARM.

YOU'RE RAISING GOOD, HEALTHY BRAINS.

AND TEACHERS ARE BRAIN FARMERS.

TO HELP US LEARN AND USE OUR BRAINS MAXALLY.

>> WE HAVE RUN OUT OF TIME FOR OUR BROADCAST SHOW.

STAY WITH US ON THE PHONE, AND WE'LL CATCH OUT FLIP SIDE.

IF YOU WANT TO LEARN MORE ABOUT THE BRAIN, GO TO OUR WEBSITE, LOTS OF OTHER INFORMATION ABOUT THE BRAIN, SO CHECK IT OUT AT IDAHOPTV.ORG.

NEXT MONTH WE'LL BE TAKING QUESTIONS ABOUT FORCE AND MOTION.

SO SEND YOUR QUESTIONS IN.

WHEN YOU DO, YOU'LL BE ENTERED INTO OUR CONTEST.

LAST MONTH'S WINNER WAS RILEY AT HILLVIEW ELEMENTARY.

THANK YOU SO MUCH FOR YOUR QUESTIONS.

AND AS ALWAYS, BE SURE TO CHECK OUT MY BLOG.

THANKS FOR JOINING US FOR THIS "D4K."

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