"We only use 10% of our brains."
So, this is not true.
"The bigger the brain, the smarter the creature."
[laughing]
Size doesn't matter.
"You can't prevent a stroke."
No.
No, that's not true.
That's very not true, actually.
Hi, I'm Dr. Santoshi Billakota.
I'm a clinical assistant professor in neurology
at the NYU Grossman School of Medicine.
I'm Dr. Brad Kamitaki.
I'm a neurologist and assistant professor
at Rutgers Robert Wood Johnson Medical School.
And today we'll be debunking myths about the human brain.
"The bigger the brain, the smarter the creature."
[laughing]
Size actually does not matter when it comes to the brain,
because there are creatures out there
with bigger brains than us, but probably not as complex.
Your brain is really determined
by your body proportion, right?
So when you think of, like, a big brown bear
that's way bigger than us,
their brain is going to be bigger,
but that doesn't necessarily mean
that they are smarter than us.
We don't know that for sure
because it hasn't been fully studied,
but we've seen that in instances such as chimpanzees.
They do have smaller brains, but we do know for a fact
that chimpanzees are probably as smart as we are.
Certainly it's not the size of the brain that matters,
but probably how complex it is
and how well developed certain areas are.
Certain areas in humans are,
for example, our language centers
are just much more developed than a cow
or a bear, things like that. Billakota: Even a chimpanzee.
Yeah. That's important in determining intelligence
rather than the size itself.
And also, how do we measure intelligence?
That also becomes tricky,
because not everyone is intelligent in the same way.
Noncognitive factors also play a role.
Like, what's your social intelligence?
What's your emotional intelligence?
All of that, I think, is very complex
and really difficult to measure.
"IQ tests are always an accurate measure of intelligence."
So, this is false.
There's so much that goes into intelligence.
Normal intelligence tests might measure things
like executive function or planning,
verbal skills, reading skills, things like that,
but it's only an approximation of what you can do
and highly influenced by the conditions of the test,
how you're feeling at the time of the test,
your educational level.
It would be nice to say that there's one test or one way
that we can determine how intelligent someone is,
but there's so much that goes into intelligence
that one test or even multiple different tests
can't measure that very well.
So, the popular IQ test was developed in the early 1900s,
and it was a way to determine
which French students were cognitively delayed
so we could offer them better resources.
That got adopted in America at Stanford.
But for all the reasons Brad laid out,
it doesn't take all of those things into account.
So I think although it is nice to say,
"Hey, I am smart, I did well on an IQ test,"
I really don't think that means too much.
Neither of us were born being doctors, right?
We had to learn and develop those skills
under many years of training.
I think that education is the best way
to kind of make that happen, education very broadly.
That might not necessarily be school for everyone.
Definitely some people are savants.
Some people are prodigies.
It's really hard to say what determines that.
They might be better at certain things
but not necessarily good at others.
We're all individuals. We all have different talents
and different aptitudes for different things.
So IQ tests just kind of measure your intelligence
in that one specific area,
not how overall intelligent you are.
"We only use 10% of our brains."
So, this is not true.
We actually use all of our brain.
Not all of the time, but most of the time,
we're using some percentage of our brain.
This myth came into fruition
I think in the early 1800s
where people were trying to figure out
why injuring different parts of the brain
caused disabilities in people.
So a bunch of psychologists came up with a theory
that we only use about 10% of our brains
versus people who are smarter, who use more.
Now we simply know that that is not the case.
We know that because we have something called a PET/MRI
and a functional MRI study.
Kamitaki: We have the frontal lobe, which we use
for a lot of different purposes,
motor function, language function,
executive functioning, or planning activities.
Behind that, our parietal lobe, here,
which is our sensory cortex.
In the back of the brain, we have the occipital lobe,
which is our visual processing center.
And then here on the side,
we have the temporal lobe, which is involved
in memory, language comprehension, on the left side.
Billakota: So to give you an example,
if you are reading something, you're going to be
using your temporal lobes for comprehension.
You're going to be using your frontal lobes
for comprehension. You'll also be using
the back of your head, where your visual cortex sits,
because that's where information from your eyeballs travel
and your body kind of makes sense of it that way.
Kamitaki: And then also, if we take the brain apart
a little bit, we have our brain stem over here,
which is kind of our lizard brain.
It's our primitive brain that controls things
like level of arousal, breathing, respirations,
heart rate, blood pressure.
We have some deep motor functions here in the brain as well.
Another part of the brain that we have
is our cerebellum, kind of on the bottom,
which is also involved in motor control and motor planning.
In doing one task,
you could be using multiple parts of your brain,
but you're not using everything at the same time.
"Video games rot your brain."
So, this is a myth.
Video games in and of themselves
don't actually rot your brain.
That's something that I definitely heard a lot
when I was younger from my grandma and my mom.
Billakota: A lot of our literature
has shown that video games,
especially the ones that focus on team building,
on solving riddles, solving puzzles,
building strategy, are actually pretty good for you.
They actually do build up those centers of your brain,
especially when you're a child.
You know, games can be used for other purposes.
For example, our colleagues in surgery,
when they do scopes, they practice those skills
with things like video-game simulators.
Looking at the trials,
no one has actually defined what too much video games is.
Every literature study that I've looked at
quotes between 12 hours to 90 hours a week is OK.
I feel like 90 hours might be a little excessive.
But I think in reality, the bigger signs
of someone withdrawing from social activities
and wanting to just stay at home and play video games
and they'd prefer to do that than do other things,
that's more of a red flag.
I always say, everything in moderation.
Like, if it's affecting your social life,
if you're just stuck in front of the TV all day,
that's not good psychologically.
"Memory gets worse as you age."
So, this is false.
In fact, there are some types of memory
that improve as you get older.
For example, things like semantic memory:
your vocabulary, reading.
Procedural memory. For example, people that are very good
at musical instruments, like, can play the piano,
often will retain those skills.
Some people will notice some change in memory.
That's often things like episodic memory,
which is kind of our memory of recent events.
Episodic memory is basically the who, what, where, and when,
so, "Where did I put my keys?
Where did I park my car?"
Those kind of things do tend to decline,
and I think a lot of it is because
we just aren't as focused on things.
It's not necessarily something that's pathological
or suggests dementia.
Kamitaki: Not everyone will get dementia,
but that risk does increase as you get older.
Right now, we don't have any medications
or treatments that can prevent someone
from getting Alzheimer's disease,
but there are some environmental risk factors
that if you address can prevent you from getting dementia
or at least prevent your memory from getting worse.
So some of those things include just general health,
eating healthy foods, taking care of your heart,
moderate exercise, making sure
that you stay healthy cardiovascularly,
which is also going to help your brain.
"Left-brained people are logical,
and right-brained people are creative."
I think the myth came from the 1800s
when, as neurologists were trying
to figure out different functions of the brain,
they discovered that the left side of our brain
in most people is dominant for language, verbal memory,
whereas the right brain was much more
of our visual-spatial functions.
But there's no structural brain difference in people
who are more logical versus more creative.
Rather, it's more their environment,
the way that they were raised.
In neurology, when we talk about
brain hemispheric dominance, we typically are talking
about language and verbal memory dominance.
Where does that live? And for most people,
that's on the left side of the brain.
Billakota: So if you're right-handed,
about 90% of the time,
you're going to be left-hemisphere-dominant,
which means a lot of your memory and speech production
and understanding, comprehension,
that kind of stuff's going to sit
on the left side of your brain,
whereas if you're left-handed,
it can kind of go both ways.
So I think the reality is,
we say that someone is left-brain-dominant
or right-brain-dominant, and it doesn't really mean
that one person is more creative
and the other one is more logical.
These are just talents and sort of skills
that people develop, whether inherently
or through their personalities,
but it really has nothing to do
with the side of their brain that they use more.
"You can't prevent a stroke." No.
That's not true.
That's very not true, actually.
You can definitely prevent a stroke.
How to do that is by really addressing
all of the factors that could result in a stroke.
We know very clearly that things
like high blood pressure, smoking, high cholesterol,
diabetes unfortunately increase your risk for a stroke,
which is basically when there's not enough blood flow
going to your brain because of a blood clot
or bleeding in the brain.
There's no quick and easy fix.
Again, it's about maintaining your cardiovascular
and brain health over time so that you never
get into a situation where a stroke will occur.
If you do ever have symptoms of a stroke,
and we often tell people this FAST mnemonic,
so facial droop, arm weakness,
slurred speech or language problems,
and then T is time.
Call 911 and get to the hospital right away
so emergency medicine physicians
can give you clot-busting medications
to break up the clot that's causing the stroke.
So there's things that we can do to address it
and prevent it from getting worse.
And I think there's a misconception
that stroke is an old person's disease.
We know this isn't true.
Anyone of any age can have a stroke.
The reason why you're going to have it
is going to be different if you're older
versus when you're younger,
but a big cause of stroke in young people is brain bleeds.
If you have a family history of aneurysm,
you should definitely get screened.
I think that's actually recommended.
"Eating fish makes you smarter."
So, I actually don't know where this one came from,
but maybe it's, like, an immigrant-household thing,
but I heard this a lot. Kamitaki: Yeah, yeah, yeah.
Yeah, yeah. I mean, in Asian households, for sure.
This is tricky because fish doesn't necessarily
make you smarter, but it is good for you,
and some fish more than others have omega-3s,
which we know are good for heart health,
good for brain health,
and just good for your overall body health.
So I think maybe that's why this one came into place,
but I don't think it makes you smarter. What do you think?
Yeah, no. I think it was my parents' way
of getting us to eat more fish.
You do have to be careful of eating too much fish.
We know that certain types of fish
have more mercury than others, like tuna.
You don't want to overdo it.
I should add that fish is part of a Mediterranean diet,
which we advocate for all of our patients.
Mediterranean diets are diets that are rich in good fats,
like fish, for example, olive oils,
vegetables, healthy grains,
and that is going to be helpful for stroke prevention.
It's going to be good for cholesterol,
for hypertension, for diabetes, all kinds of stuff.
So fish as part of a healthy diet is good for you,
but it will not make you smarter.
"You can always trust your senses."
I would say that's a myth.
So, our senses can play tricks on us and cause things
like illusions or even sometimes hallucinations.
For example, people with schizophrenia might hear voices
of people talking that aren't actually there.
Our senses are not 100% objective.
They're dependent on how well our brains
and eyes, ears are functioning at that time.
Everyone is different.
My pain tolerance might be lower than Brad's or vice versa.
I don't think we have a really good neurological way
of explaining why that might be.
That's still something that we don't fully understand.
And also, your senses can be a little influenced
by emotions and memories, I think.
If you see something that reminds you of someone,
the way you're going to react to it
might be a little different.
I don't know if what I'm seeing is the same thing
that everyone else is seeing. Like, how can we ever
know that for certain? Billakota: It's like when they
had that blue dress and the black dress
and people were seeing different things.
"Different sexes have different brains."
So, no, that's not true, and I'm going to rip it again,
'cause that was less funny.
I should start with saying
that we're all born with the same brain,
regardless of what your gender identity is,
regardless of what your sexual orientation is.
There's really no structural differences.
So if a neurosurgeon was looking at two different brains,
they wouldn't know who was assigned male at birth
and who was assigned female at birth.
There have been studies out there that have shown
that those who have been assigned female at birth
might have more robust emotional pathways,
whereas those who have been assigned male at birth
are more executive thinkers.
We now know that that's not true.
As you get older,
if you've been exposed to different things,
how you relate to the outside world,
that's what develops the structures
of your brain and the connectivity.
It has really nothing to do
with what gender you were assigned at birth.
It's more nurture.
It's not necessarily nature and how you're made.
"If you have a seizure, you have epilepsy."
No!
I'm going to rip this a few times
because I want to make my point.
What a seizure is, is hypersynchronization of brain cells.
So what is that? Your brain talks to itself
using electricity. If something goes wrong
with the electricity in your brain, you have a seizure.
Basically, when all your neurons freak out and fire at once,
your body hypersynchronizes, and we have a seizure.
Seizures can be due to a lot of things,
not necessarily epilepsy,
which is a lifelong neurological condition.
You have to have multiple unprovoked seizures,
and that's the difference between a seizure and epilepsy.
Also, if you have epilepsy,
you have to take daily medication
to keep your brain from having seizures.
So if you have had your first seizure of lifetime
or if you're someone with seizures,
there are a few things that you should do.
One, definitely get checked out by a neurologist.
There are tests that we can order
that can be helpful for you.
One of them is an EEG.
We put stickers on your head, look at your brainwaves,
and see where the abnormalities are.
And the second one is the imaging that we have.
MRIs and PET/MRIs are both used.
And if a diagnosis of epilepsy is made,
the most important thing for you to do
is take your medications.
And lastly, keep communicating with your doctor,
because you're not going to get
to that period of seizure freedom
unless you communicate with your doctor.
You only get one brain.
You're born with all the brain cells
that you are going to have,
and it's up to you to take care of them.
There's a grain of truth in a lot of these myths,
but they're just not fully accurate.
Just make sure that you do your research
and take care of yourself.