
Our Brains Are Not Multi-Threaded - janvdberg
http://www.calnewport.com/blog/2019/09/10/our-brains-are-not-multi-threaded/
======
frereubu
The language here is weird. He's talking about doing more than one thing at a
time. If you're talking about multi-threading in the context of the brain, the
obvious comparison is with neural architecture. The brain does a massive
amount of parallel processing and it very much _is_ multi-threaded. But
"multi-threading" sounds a bit cooler than "doing more than one thing at a
time" I guess.

~~~
rhombocombus
There is a big difference between multitasking and parallel processing. As a
former neuroscientist I get rankled when I read gross conflations like this,
it doesn't help anyone understand how the brain actually works, nor does it
effectively underscore the attentional drawbacks of trying to multitask.

~~~
frereubu
Fellow former neuroscientist here! The proliferation of pseudo-neuro
explanations and analogies is infuriating. I envy people like theoretical
physicists who work in a field where laypeople don't feel like they have an
intuitive understanding of their subject area.

~~~
posterboy
I for one am a specialist on quantum mechanics since I read Steven Hawking.
It's all bonkers, I can tell you that, but because of the uncertainty
principle, I'm not really sure. That's OK because there is some parallel world
in the multiverse in which it isn't. And please don't ask me to explain, I've
read enough to know that by Hoffstadter's Incompleteness theorems I cannot
prove it.

~~~
Jd
I know that dog created the universe with a pair of parentheses and after that
it was pretty much backwards and uphill.

ok maybe not: [https://xkcd.com/224/](https://xkcd.com/224/)

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thisisbrians
In the tech community, we talk a lot about not interrupting programmers (or
other knowledge workers) because of the cost of so-called "context-switching."
I think this post raises the very interesting point that, much of the time,
the sources of these interruptions are not external, but internal. Stop
interrupting yourself! You're a knowledge worker! His advice to cultivate
systems that afford one focus and prevent context-switching is salient.

~~~
perl4ever
It's a cliche that IT as an industry is hostile to women, and it's also a
cliche that women are good at multitasking.

How do we know that people's opinions on the difficulty of multitasking are
representative and not biased?

I'm not even speculating on whether gender differences might be innate or
trained.

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pinky1417
Cal's essay is backed by empirics. I'd add that, for those like me who used to
believe that women are better multitaskers, both men and women are equally bad
at multitasking. Early studies would sometimes show a female advantage or a
male advantage (not sure why the female advantage idea came to be popular),
but they were based on humans performing tasks that didn't resemble the real
world... or at least tasks from the world of business/office work.

A newer study, based on a real world task of meeting preparation, showed that
both men and women were quite bad at multitasking:
[https://link.springer.com/article/10.1007%2Fs00426-018-1045-...](https://link.springer.com/article/10.1007%2Fs00426-018-1045-0)

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posedge
I feel like everyone in this thread arguing about multi-
threading/hypterthreading/multi-core/multi-processor as an analogy is missing
the poing. The post is about how you can focus your _attention_ on a single
task only (true multitasking doesn't exist) and that you should keep focus
longer instead of switching context too often.

~~~
jugg1es
That's because the author is saying that the brain cannot perform parallel
processing, which is clearly not true. You are making a distinction that the
author does not.

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gorzynsk
Consciousness about what our brain does is single threaded. Everything else is
massive parallel processing.

~~~
dclowd9901
Right. Thank god I don't have to think about breathing or making my heart
beat.

~~~
serpix
What you don't think happens on its own and what you think also happens on its
own. The illusion is that thinking is you, identification with thinking. Once
that is seen as an illusion you can observe yourself talking, thinking and
verify all this happens on its own.

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thrax
Effective task switching is a learned skill.. I often find that switching
between 2 or 3 tasks a few times over the course of a day, helps me be more
productive because blocking is less of an issue and sometimes blocking due to
problems needing to be solved, can be iterated on subconsciously while you're
forebrain is doing something else.. I think there are parallels with neural
networks.. task switching helps make your network generalize better.

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jlv2
> In a world before multi-core processors, these threads weren’t actually
> running simultaneously, as the underlying processor could only execute one
> instruction at a time.

This is not true. Before multi-core processors there were _many_ computers
with multiple CPUs.

Is the author under 30 or something?

~~~
wilg
You don't think its true that before there were multi-core processors,
processors could only execute one instruction at a time?

It doesn't say computers could only execute one instruction at a time. It says
processors.

If you're going to do needlessly pedantic bikeshedding, at least get it right.

~~~
qes
> You don't think its true that before there were multi-core processors,
> processors could only execute one instruction at a time?

It is not true.

Instruction-level parallelism existed before multi-core.

> If you're going to do needlessly pedantic bikeshedding, at least get it
> right.

Pot, meet kettle.

~~~
wilg
I don't care at all about this discussion! I was just trying to ding the
commenter for going off on a tangent. Also, the person I'm replying to wasn't
talking about instruction-level parallelism, they were misreading the article.

~~~
pathseeker
>I don't care at all about this discussion!

Then don't say shit like "at least get it right".

------
Insanity
Whenever these comparisons of brains and computers come up, I am reminded of
Freud's comparison between the brain and the steam engine.

People think about the world (and brain in this case) in terms of what they
are familiar with. Today computers are ubiquitous and we try to see computers
in nature. In 100 years it will be something different and we'll try to
imagine the brain like that.

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nitwit005
Lacking in evidence and uses vague terms like "psychic toll".

~~~
beat
I think simple observation provides plenty of evidence. It's not a real
scientific-method approach, but if you want to dismiss the relationship he's
talking about, you need either to find a flaw in his reasoning or offer a
better alternative explanation for the observation that when people try to
"multitask", they usually do a shit job of it.

~~~
nitwit005
You can feel free to have whatever standard you want as to what makes up a
worthwhile article. Someone's personal feelings on how the human mind
functions, described with vague terms, is essentially worthless to me.

Given that the same complaint seems echoed in other comments, I'm not alone
there.

~~~
beat
My atttitude toward a Cal Newport article is that he's published multiple
highly regarded books that I've read and found very insightful and applicable
in practice. So when he writes something that's brief and does some
handwaving, but fits within his overall worldview (like this article), I'm
inclined to take it more seriously.

If you've never heard of Cal Newport before now, I can see reason for some
doubt, but I also think you're maybe missing out on a lot within the field.

~~~
Apocryphon
His blog articles were both more concise and more valuable than his bloated
books.

------
aloknnikhil
Multi-threading is not a good analogy. If you think of the conscious brain as
a hyper-visor which is switching execution context between multiple virtual
machines, the analogy sticks slightly better. Running too many VMs (on what
seems like a single core processor) will slow things down and is akin to
context-switching between "neural activities". It's a whole host of things
that the processor needs to setup before executing instructions in a sandbox.
Switching between threads is cheap and the conscious brain does it all the
time, even when you're focused on a single task.

But it's all so relative and comparing it to a "computer" and claiming it's
not efficient is not fair. In fact, I'd argue that the human brain is a lot
more efficient at handling tasks because not only is it executing
instructions, it's constantly learning and programming the next set of
instructions.

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m12k
A better title would be "Our Brains Are Not Multi-core' \- so multitasking,
just like multi-threading on a single core CPU, will incur a penalty of
context switching, cache misses, and so on.

~~~
PyroLagus
Looking at split-brain patients, it does seem like each hemisphere is a "core"
which communicate via the corpus callosum. So you could say that our brains
are multi-core.

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nice_byte
"it’s often much easier for the programmer to write independent threads, each
dedicated to its own part of the larger system."

oh, if only it were true...

~~~
doubleunplussed
Im one of these people who reaches for threads to solve many a task, and that
statement resonates for me. I've never understood why threads are considered
so difficult, other than people not getting the message to sparingly share
data other than via message-passing.

Any time you need to do something asynchronously, things get trickier, but
whether you keep it single threaded or not barely makes any difference. Race
conditions exist in single threaded code too as soon as it is interacting with
a network or the OS or anything that takes time and you don't want to block.

It's not threads that are hard, it's the explosion of the state space of your
program when you commit to accepting further user/network input whilst some
task is ongoing, whether you implement that with threads or not.

------
generaljelly
If you want to read something interesting on how thinking works I suggest
'Thinking, Fast and Slow' by Daniel Kahneman.

~~~
perchard
I enjoyed TFS but tend to agree with this review:

> Thinking Fast and Slow is my runner-up for “book most overrated by
> investors” (with Klarman’s Margin of Safety the champion.) People who pitch
> this book as “required reading” simply haven’t read broadly enough about
> cognitive biases: while the content is certainly useful and I don’t take
> anything away from Kahneman as a researcher, his
> writing/communication/worldview leave much to be desired, and the same
> lessons can be learned far more effectively and enjoyably via a variety of
> other books (many of which are suggested below).

[http://www.askeladdencapital.com/daniel-kahnemans-
thinking-f...](http://www.askeladdencapital.com/daniel-kahnemans-thinking-
fast-and-slow-book-review/)

------
banachtarski
AKA our brains are hyperthreaded. The observation doesn't seem that salient.

That said, I believe the article to be incorrect. Our brain does do various
sorts of parallel processing (visual cortex, keeping your heart beating,
maintaining sense of balance, etc). It's just that the cores happen to be more
specialized.

~~~
SamReidHughes
You can add many learned things, like driving, riding a horse, playing the
piano, and attacking math problems under time pressure to the sort that
apparently involve parallel processing.

------
djsumdog
> Imagine, for example, you’re creating a basic game. You might have one
> thread dedicated to updating the graphics on the screen

Has the author has never actually written a game? The majority of games are
single threaded. You calculate the positions, moves, strategy of the AI, etc.
etc. and then eventually render the frame. For years, certain releases of Doom
and Quake were the benchmarks for games because they were some of the first to
use multiple threads and could scale to multiple CPUs/processors.

Sure, modern games tent to be able to use more cores and have some independent
threads, but the majority of the work typically still happens in the main
event loop.

------
Eli_P
Listen to Terence McKenna's recordings where he describes tripping experience,
or somebody doing DMT, or Michael Stevens doing ayahuasca. Maybe all these
observations are anecdotal and not scientific, but it feels like ideas and
thoughts live their own lives inside neocortex.

Our brain's potential is harnessed with reptile and mammal tasks which are
more asynchronous than parallel. Even if we could overclock ourselves into
massive parallel thinking it would have ended up with oxygen or glucose
deficit. And mind overheating, whether cpu is made from silicon or grey
matter, there's a limit for FLOPS per joule.

------
zeroimpl
I’ve generally found that a context switch from one programming task to
another can be pretty easy (even if totally unrelated), but switching to
something non-programming related is often much more painful.

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cy6erlion
The brain is the hardware, consciousness is experienced in the mind, the mind
is the faculty for processing thoughts it is also the same faculty we use to
perceive the self/ego and our reality with help from sensed data. The highest
level of our consciousness the mind appears single threaded because the
perceived self/ego is attached to the minds thread, multi threads will be like
multi self. But we can be conscious of the fact that we are thinking, that is
itself a sort of thread running, and we can perceive that one also, and the
other...

~~~
Gene_Parmesan
Sometimes when I'm meditating I experience a mini ego-loss. I come out of it
feeling like I'm merely a collection of running processes over which I have
little to no control. I feel like I get a brief glimpse of 'multithreads,' and
it's somewhat emotionally unpleasant.

~~~
cy6erlion
Yes exactly. My first comment was based on what I experience when meditating.

> I feel like I get a brief glimpse of 'multithreads,' and it's somewhat
> emotionally unpleasant.

I think it helps not to identify the self as the thoughts/processes of the
mind, the self is the observer/awareness

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jugg1es
This article is nonsense and I don't think any background research was done
before writing it. It takes almost no effort to come up with an example of
parallel processing in the brain. Pat your head and rub your tummy at the same
time. How many times have you been driving and talking and listening to the
radio at the same time?

He must mean that conscious attention is not multi-threaded, and that is
obviously true because the nature of paying attention is that you are focusing
on a single thing.

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karmakaze
As I read it, it seems to be saying that our brains _are_ multi-threaded, but
not multi-core or multi-processor.

The lower priority 'threads' which are not the intended focus still do take
cycles in brief moments when the main task is idle only to be preemptively
interrupted at the cost of many context switches and adding very little value.
The same happens with hardware CPUs which is why coroutines are much more
effective when the number of tasks >> number of processing units.

~~~
karmakaze
Also we do have multiprocessing abilities, just not multiple 'foreground'
conscious ones.

~~~
AstralStorm
We sort of do, but at best it's not more efficient, at worst it's much slower.

~~~
karmakaze
I've never experienced being aware of two unrelated things at the same time so
I definitely have a single-core consciousness.

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kordlessagain
> This is all to say that the closer I look at the evidence regarding how our
> brains function, the more I’m convinced that we’re designed to be single-
> threaded, working on things one at a time, waiting to reach a natural
> stopping point before moving on to what’s next.

So it's another hypothesis, parading around as a common claim.

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quickthrower2
My brain is. I am simultaneously looking at the screen while writing this
comment by tapping my fingers too.

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stratosgear
I'm not sure this is a great example of memorization or multithreading but
playing chess blindfolded against three opponents, is out there:
[https://youtu.be/xmXwdoRG43U](https://youtu.be/xmXwdoRG43U)

~~~
sherkaner
That's actually pretty easy for any experienced chess player. The world record
is simultaneously playing 45+ opponents blindfolded, which is actually
incredibly hard.

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dr_dshiv
Multiplexing in the brain is apparently achieved by maintaining a high and low
(theta) peak frequency -- when at a ratio of the golden mean, each separate
period of high activity doesn't interfere with the other. Makes sense, when
you think about brainwave bands being harmonics (frequency doublings), as that
is what permits frequency coupling-- whereas irrational ratios prevent
coupling.

Pletzer, B., Kerschbaum, H., & Klimesch, W. (2010). When frequencies never
synchronize: the golden mean and the resting EEG. Brain research, 1335,
91-102.

~~~
dr_dshiv
Btw, I know that anything involving golden mean smells like crank science.
Note that Wolfgang Klimesch is field topping in EEG research citations...

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fucking_tragedy
A computer is a bad metaphor for the brain, there's no reason to strain the
metaphor even further by dragging threading into it.

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softwaredoug
There’s a special irony to being distracted enough by a Cal Newport article to
feel the urge to comment on it!

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LoSboccacc
not in the time slice way we programmer usually think when taking about multi
threading, but how many times you let a problem be only too have an epiphany
some time later? background thinking is very real and albeit not a fair
allocation system it is, in a sense, threading.

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afinlayson
Yet! Give it time, we'll add a peripheral port soon enough

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test132
More complex than any man made machine

