
Debunking the Myth of 10% Brain Usage - iuliangulea
https://iuliangulea.com/blog/debunking-the-myth-of-ten-percent-brain-usage/
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Exmoor
For some reason this reminded me of one of my favorite Wikipedia pages:
[https://en.wikipedia.org/wiki/List_of_common_misconceptions](https://en.wikipedia.org/wiki/List_of_common_misconceptions)

I read through it every couple of years and am amazed at the number of things
considered "common knowledge" which are completely untrue.

~~~
iuliangulea
That is a great list you've shared. Thank you!

It takes a great deal of self-consciousness to keep an eye on such things that
feel like "obvious truths," just because you grew up in an environment that
was reinforcing those misconceptions.

~~~
AdmiralAsshat
Probably inspired by:

[https://xkcd.com/843/](https://xkcd.com/843/)

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tlarkworthy
This article does not really debunk anything as it seem to use some very poor
chains of reasoning:

"If we are using only 10% of our brains, that means a person would be fine if
the other 90% of the brain got removed. 10% of the 1400g average brain is
140g—that’s the size of a sheep’s brain.4 Since I doubt sheep have their own
90% hidden potential myth, it makes no sense that humans have advanced so far
as a civilization by using only part of their brains equivalent in size to a
sheep’s brain."

1\. That using 10% of brain means 90% can be removed. Where did that logic
come from?

2\. That size of the brain is important (i.e. the size of a sheep brain is
relevant to human intelligence, this is a poor argument as an elephants brain
is much larger than a human's)

~~~
iuliangulea
Thanks for being attentive and spotting potential flaws in the article.

1\. I don't really know how to answer this to you other than with
"arithmetic."

2\. Have you read the entire article? There is the "relative" part. Elephant's
brain-to-body mass ratio is 1:560. And yes, brain size is important. Some
small birds have 1:12 brain to body ratio, but that doesn't make them smarter
than us.

~~~
tlarkworthy
I kinda agree with the article just not the reasoning that got to the outcome.

1\. Saying we use 10% of our brains doesn't imply 90% of the mass is
unnecessary. It could be saying 90% of the electrical activity is unnecessary,
or 90% of the synapses are unnecessary. I don't believe the myth, but doing a
hard logic stop from 10% to that means 90% of weight is unnecessary is not
implied by the statement we are arguing against. It's nothing to do with
arithmetic.

2\. If you look at the article one of the 1st headings is "Size Does Not
Matter". So does it matter or not? When you look closer the stand out features
of humans is a wrinkly grey matter, so surface area (i.e. grey matter) seems
important and mass based arguments are a correlation to that. (also big bodies
have more sensory area so their is an inverse correlation to body size too)

Anyway, I think the point of the myth is to say humans have more potential
than their default. If you take some Ritalin or Cola you might agree that the
natural brain can be souped up a bit cognitively (not by 10x). Experience and
learning also gets more out of an (nearly) identically sized brain too. You
can't take an experience brain and cut half of it out to become a toddler
again though

~~~
iuliangulea
Thanks for the clarification. Now it's clearer why you wrote the first
comment.

1\. I think you and I have different understanding of that myth. I was
referring to the fact that people think 90% is not used _at all_. I might have
done a poor job of emphasizing that thing, that's why we are discussing this
now.

2\. I haven't looked at it that way. It's an instance when the paragraph name
interfered with some important concepts in the entire article... The point in
"Size Does Not Matter" that I have envisioned is that being a such a small
fraction of the body, the brain consumes unproportionately more energy.

The point of Ritalin and Cola is that those increase the blood glucose level,
which aids in cognitive processes.

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alexpotato
When the article mentioned brain size, it reminded me of a story about
Einstein's brain.

He donated his brain to science and one of the first things noted after his
death was that his brain was roughly average sized. This was a big setback for
the "brain size correlates with IQ" crowd and was one, of many data points,
showing that brain size and volume did not correlate with IQ.

Years later, as we got better understandings of the brain and its sub-
components, it was realized that he was actually MISSING a part of his brain.
I forget the exact piece but what was most interesting is that it was the
portion of the brain that "pushes" up against another of the brain believed to
be used for visualizing problems.

Because he was missing the first component, it allowed the visualization
portion to grow to roughly double the size of a normal person's. It's thought
that this "supercharged" his ability to mentally visualize complex physics and
math problems in a way average people couldn't.

To me, it's fascinating that missing part of you might lead other parts of you
to becoming more efficient and/or more powerful.

EDIT: Fixed some grammar.

~~~
YeGoblynQueenne
Wikipedia has an article on Enstein's brain that says that, because a region
of his brain was vacant, neurons in that part of the brain may have
communicated better. It also mentions Einstein used to say he always thinks
visually, but from what I can tell from the article that doesn't have
something to do with an enlargement of the area of the brain that is
responsible for visualisation. That's how I read the below anyway. Also note
that the examination that concluded a part of his brain was missing was based
on photographs of the brain and not a direct autopsy.

 _Autopsy_

 _Harvey had reported that Einstein had no parietal operculum in either
hemisphere,[12] but this finding has been disputed.[13] Photographs of the
brain show an enlarged Sylvian fissure. In 1999, further analysis by a team at
McMaster University in Hamilton, Ontario revealed that his parietal operculum
region in the inferior frontal gyrus in the frontal lobe of the brain was
vacant. Also absent was part of a bordering region called the lateral sulcus
(Sylvian fissure). Researchers at McMaster University speculated that the
vacancy may have enabled neurons in this part of his brain to communicate
better. "This unusual brain anatomy...[missing part of the Sylvian fissure]...
may explain why Einstein thought the way he did," said Professor Sandra
Witelson who led the research published in The Lancet. This study was based on
photographs of the whole brain made at autopsy in 1955 by Harvey and not a
direct examination of the brain. Einstein himself claimed that he thought
visually rather than verbally. Professor Laurie Hall of Cambridge University,
commenting on the study, said, "To say there is a definite link is one bridge
too far, at the moment. So far, the case isn't proven. But magnetic resonance
and other new technologies are allowing us to start to probe those very
questions."[14]_

[https://en.wikipedia.org/wiki/Albert_Einstein%27s_brain](https://en.wikipedia.org/wiki/Albert_Einstein%27s_brain)

Also, note:

 _Selection bias may have influenced published results, which means that
results showing differences between Einstein 's brain and other brains tend to
get published while results showing that in many respects Einstein's brain was
like other brains tend to be neglected. Researchers knew which brain was
Einstein's and which were controls, allowing possible conscious or unconscious
bias and preventing impartial research._

[https://en.wikipedia.org/wiki/Albert_Einstein%27s_brain#Crit...](https://en.wikipedia.org/wiki/Albert_Einstein%27s_brain#Criticism)

I'd think that, indeed, one has to be very careful about confirmation bias in
this kind of study. Not least because Einstein was very famous and having some
grounds to claim that "he was a genious because of how his brain was made" is
something that can grant some publicity to a researcher's otherwise obscure
work.

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doublekill
We can use 90% of our brains at the same time, but the medical term for that
is a seizure and it seems to involve a lot of involuntary movements.

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vilhelm_s
> If we are using only 10% of our brains, that means a person would be fine if
> the other 90% of the brain got removed [...] There are instances in history
> when people were injured and got parts of their brain removed (although not
> as close as even 10%)

Actually you can do much better. There are people who had 50% of their brain
removed and were fine.
[[https://en.wikipedia.org/wiki/Hemispherectomy](https://en.wikipedia.org/wiki/Hemispherectomy)]

And there are examples of people who lost up to 95% of their brain and still
seem pretty normal. (Actually, some are claimed to be be _smarter_ than
average, leading to the suggestion that the rest of the brain is just cramping
our style, but that's probably an exaggeration.)
[[https://www.gwern.net/Hydrocephalus](https://www.gwern.net/Hydrocephalus)]

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Tenoke
> If we are using only 10% of our brains, that means a person would be fine if
> the other 90% of the brain got remove >> Actually you can do much better.
> There are people who had 50% of their brain removed and were fine.

50% is less than 90%, that's not 'much better'.

>[[https://www.gwern.net/Hydrocephalus](https://www.gwern.net/Hydrocephalus)]

It's amusing you link to gwern's page where he mostly debunks those cases.

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vilhelm_s
I think the page is saying that the largest injuries destroyed less than 10%
of the brain, leaving more than 90% intact. 50% is more than that.

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HPsquared
It's like saying only one cylinder of a four-cylinder engine is 'working' at
any given time. Technically true in a way, but somewhat misleading.

~~~
Izkata
Yeah, something along these lines is what I've always thought was going on:

* It probably is true that on average, only 10% of neurons are firing at a given instant in time.

* Lay-people misunderstood this to mean the other 90% aren't doing anything,

* When actually, if all 100% were firing there'd no longer be a differential and the brain would stop working.

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mywittyname
> It probably is true that on average, only 10% of neurons are firing at a
> given instant in time.

This makes sense. A lot of utilization in nature follows a Pareto
distribution, where frequency of use leads to an increase in frequency of use.
It's likely that only 10% of roads are in use at any given time, but that
doesn't mean that you can eliminate 90% of roads and still have the same
capabilities.

It's not feasible to utilize 100% of ones brain because there's a fundamental
limit to the number of simultaneous activities we can undertake. You might be
able to juggle, play an RTS game, figure out the flavor components of a dish,
and recite the US Constitution backwards, from memory. What you can't do is
all these things simultaneously.

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TheOtherHobbes
It's a metaphor for general ability, not a concrete estimate of actual
physical brain usage. People who use it tend to mean "You, yes _you_ , could
amazing and magical things if you were more focussed."

That's very unlikely to be literally true in the way they hope. But given how
poorly most people are educated, and how often they're fed lies and
distortions in adulthood, there's likely to be some metaphorical truth to it.

So the population as a whole certainly could be smarter, more aware, more
effective, and probably more creative too.

But it's not something you could easily put a number on. Certainly a one
dimensional measurement like IQ won't capture it.

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talove
Not sure how this is on the front-page. The article chases to debunk something
that is only used as a metaphor for the capacity of the mind. IMO the idea
that we only use 10% of our brain is oversimplified way to get the attention
of a child when conveying the minds power. For example, you only activate 10%
of your brain when reasoning a difficult math problem, or recalling a memory.
I don't think anyone ever asserted that 90% of your brain is turned off.

~~~
iuliangulea
If you haven't heard about this myth previously, you grew up in some good
environment, I shall say.

[https://en.wikipedia.org/wiki/Ten_percent_of_the_brain_myth](https://en.wikipedia.org/wiki/Ten_percent_of_the_brain_myth)

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sunstone
Evolution doesn't waste resources unnecessarily. The human brain requires
substantial energy to operate, why would brains have evolved they way they
have unless there was a purpose for very close to all the power of the brain?

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onion2k
I'm a JS dev. There's no way I use as much as 10%.

~~~
cultus
When I write JS, I think I'm at peak usage trying to figure out what the hell
is going on with the code I've written.

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himinlomax
Geniuses use 100% of their brain, just like champion drivers use the gas
pedal, brakes and door handles all at the same time.

