
Face It, Your Brain Is a Computer - fractalb
http://www.nytimes.com/2015/06/28/opinion/sunday/face-it-your-brain-is-a-computer.html?action=click&pgtype=Homepage&module=opinion-c-col-right-region&region=opinion-c-col-right-region&WT.nav=opinion-c-col-right-region&_r=0
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coldtea
I find the metaphor bad.

My brain might work like a computer (computation et al), but the word computer
evokes actual existing computers to a layman -- and my brain doesn't have a
von neumann architecture, nor does it run something similar to our software.

A neural network does computation of course, but we wouldn't call it a
"computer" in the sense we use the word when dealing with, well, computers.

~~~
mcphage
> and my brain doesn't have a von neumann architecture

"Computer" doesn't automatically equal "von neuman architecture".

> nor does it run something similar to our software

A lack of software-equivalent is a pretty good criticism, though.

~~~
coldtea
> _" Computer" doesn't automatically equal "von neuman architecture"._

No, but that's what most people are familiar with (if they are familiar with
computer architectures in the first place), so it pretty much equals that for
them.

~~~
mcphage
> that's what most people are familiar with (if they are familiar with
> computer architectures in the first place)

They're not. There's really only two kinds of people here—those who are
unfamiliar with computer architecture (99% of the population), and those who
are familiar with Von Neumann architecture, and know that it's not the only
game in town.

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themgt
I think the key fail is hidden beneath this statement, 'many “digital”
computer switches are built out of analog components and processes'. In fact
obviously, all computers are built out of analog components, in the sense that
the entire universe is analog.

However, this is the problem. Computers are designed to interpret or translate
the messy analog world where nothing is exactly 1 or 0, into a precise,
deterministic digital world where everything is either 1 or 0. And I think
it's highly likely that the brain does not work in this manner whatsoever, and
that in fact, in the translation of reality into 1s and 0s, you've lost far
too much to properly "compute consciousness"

Would it be possible to build a synthetic brain out of some form of "analog
computer", capable of consciousness? Almost certainly. But since we have no
idea what sort of architecture or paradigm that would use, or how we would
program it or whether it would even "execute instructions" in a way remotely
similar to digital computer software, such a declaration becomes meaningless.

~~~
jwmerrill
> Computers are designed to interpret or translate the messy analog world
> where nothing is exactly 1 or 0, into a precise, deterministic digital world
> where everything is either 1 or 0. And I think it's highly likely that the
> brain does not work in this manner whatsoever

But neurons totally do work by encoding information with discrete signals.

[https://en.wikipedia.org/wiki/Action_potential#Process_in_a_...](https://en.wikipedia.org/wiki/Action_potential#Process_in_a_typical_neuron)

Action potentials are discrete events, and just like hi or lo in a silicon
computer actually correspond to a range of voltages, the exact voltage-vs-time
curve of an action potential likely has considerable flexibility.

~~~
cinquemb
Though, not all neuroscientists are on the same page nor agree with the claims
some people want to make…

"The frequency of action potentials (APs) generated by neurons is correlated
with different events; however, it does not mean that such events are
‘encoded’ in the brain using the firing rate or any other ‘temporal code ’
(e.g. interspike interval)…

…Simultaneous firing of action potentials (synchrony) in a neuronal ensemble
increases the interaction of many- body systems and implicitly boosts the
computational power [7]. The well accepted model of ‘activation function’ that
describes artificial neurons simulated on Turing Machines does not approximate
the process of ‘solving equations’. Therefore, the popular claim that current
artificial neurons and neural networks are ‘realistic’ models of their
biological counterparts is misconstrued and untrue."[0]

[0]
[http://arxiv.org/ftp/arxiv/papers/1210/1210.1983.pdf](http://arxiv.org/ftp/arxiv/papers/1210/1210.1983.pdf)

~~~
themgt
Wow, fantastic paper:

 _However, the relevance of Turing model is questioned even in case of
present-day computing [33] [34]. Indeed, any computing machine that follows a
Turing model would be highly inefficient to simulate the activity of
biological neurons and experience an increased slowdown. Since the super-
Turing computing power of the brain has its origins in these ‘strong’
interactions that occur inside neurons, current models have missed the most
important part. Simply, Nature doesn’t care if the N-body problem has
analytical solutions [36] or can be simulated in real time on a Turing machine
[37].

...

While previous models have attempted to represent Hamiltonians using Turing
machines [35] the paper [1] shows that the Hamiltonian model of interaction
can represent itself a far more powerful model of computation. Turing made an
important step forward; however, there is no need to limit natural models of
computation to Turing models. In this sense, the new framework of computation
using interaction is universal in nature and provides a more general
description of computation than the formal Turing model. In other words God
was unaware of Turing's work and has put forward a better model for physical
computation in the brain._

~~~
cinquemb
I thought it was fantastic as well (because you know a theory that tries to
incorporate our understanding of matter and energy [which the brain is a
subset of] in a field with a lot of hand-waving going on, shouldn't be that
radical…), though for most neuroscientists it is out of reach because for the
most part, have little to no understanding of electromagnetism (let's set
aside the QED versions of Maxwell's equations) from my experience, which is
quite ironic considering the tools that are in heavy use…

The amount of money being wasted trying to make special FMRI's and custom EEG
caps is lost on me when attempting to solve equations along variable boundary
conditions seems like it should come first…

Here's the paper the author wrote which that paper is branched from:
[http://www.researchgate.net/profile/Dorian_Aur/publication/2...](http://www.researchgate.net/profile/Dorian_Aur/publication/202222729_Dr/links/0d1c84f6f4b8a37018000000.pdf)

~~~
themgt
Thanks! That paper/book is going on the reading list. I need to bring this up
with some neuroscience friends.

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linschn
The only serious counter-argument I've heard against the hypothesis that the
brain goes further than a Turing machine is that the brain does not implement
an algorithm, with one input, some processing steps, and one output.

Instead, it processes information as it comes, this information comes during
the processing of previous information and the output partly loops back to the
input. Short-circuits everywhere, no clock, etc. I'm unconvinced but I could
not refute the argument formally.

Note that this does not contradict the Church-Turing Hypothesis : if you
restrict the brain to one input, some processing steps with a pen and paper
without arrival of new information, and an output, then it is very possible
that the brain can only work out Turing-computable problems.

~~~
guard-of-terra
'information comes during the processing of previous information and the
output partly loops back to the input"

Computers do this all the time. Simplest example is "cancel" button
everywhere.

~~~
linschn
The point is that out definition of the computability of a function is too
narrow, and does not take into account the real-time all connected nature of
the computation the brain does.

Therefore, we lack formal way of satisfactorily compare the brain to a Turing
Machine.

~~~
guard-of-terra
I don't see why. Your computer reacts to keyboard and mouse in the real time,
also for network packets going in and out. And it's plain turing machine. It
does so by regarding every input as they become available, one by one.

Information comes to brain via neurons, and those have finite speed, it's not
as they had quantum-like properties. Signal in; signal out, with delay and
altered magnitude.

~~~
linschn
The important word is : formal.

I, too, think that the brain is 'a computer'. But the formal definitions of
computation we have today require the computer to be left alone for some time
between the moment the input is given and the moment the output is due. The
brain does not work like that, ergo we lack a formal model of how the brain
operates, and thus the definition of 'computable function' -which is based on
our model of computation- is less general than what the brain can do.

e.g. We have no proof that the only way neurons communicate with one another
is via the synapses.

~~~
guard-of-terra
Brain, too, needs some time to react to any incoming event.

I fail to capture the difference.

------
ScottBurson
I'll never forget hearing Jerry Lettvin [0] pronounce, in his slow, measured,
way: "The brain is not a computer. The brain _is a gland_."

I think he said it partly to tweak his MIT AI Lab audience (this must have
been about 1982). But he had a point: a lot goes on in the brain that is not
digital.

[0]
[https://en.wikipedia.org/wiki/Jerome_Lettvin](https://en.wikipedia.org/wiki/Jerome_Lettvin)

~~~
guard-of-terra
My computer also doubles as fan and vacuum cleaner.

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samatman
This is entirely backwards.

Computers are designed to emulate brains. More specifically, to perform a
certain category of brain activity (calculation).

To date, a brain is still needed to make a computer do anything. No brain, no
software; no software, all we have is an inert lump of metals and plastics.

We should be quite wary of reversing metaphors in this fashion. 19th century
psychology contained a number of metaphors derived ultimately from the steam
engine, for human consciousness, and for reality. All we've done is update the
machine; the comparison is still backwards.

------
sukruh
Any reasonable definition of computer includes things that can do arithmetic,
and since brains can do that, brains are computers.

The distinction between analog and digital computers doesn’t seem to be so
important to me. Any computation that an analog computer can do, can also be
done with digital computers and vice versa. Digital computers can process
continuous-time signals as precise as analog computers, and analog computers
can do logic. Which kind of computer you use depends on convenience with
respect to the resources and computational problem in hand.

The “brains don’t download software” part also isn’t convincing. Brains are
capable of manipulating symbols, but the rule set needs to be learned in the
case of arithmetic, or selected, in the case of natural language according to
inputs. Also, software doesn’t have to be like “1. Do this, 2. Do that, 3.
End”, like the article implies. The brain can be running on a game loop,
planning future actions according to some stochastic utility function.

Also, I find it useful when thinking about brains to separate the functions
that are done unconsciously from those that are not. To me, unconscious
functions of the brain seem more like using specialised hardware. Of course,
those parts are almost certainly doing computation to full their functions,
but it is “not abstract symbol manipulation according to some learnable rules”
that people associate with consciousness.

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logician76
As long as science keeps thinking this, we won't have to worry about the
singularity any time soon.

~~~
nirai
The problem here is that the so called singularity does not necessarily depend
on machines having the so called qualia.

------
avera
My closest belief is near similar as mentioned in article, that brain, at some
level has some "computational primitive", which resembles transistor
functionality.

But that is only one level. There can be additional layers of function, which
can be influenced by sub-atomic entities, like elementary particles. We still
don't know how deep this goes. This is, what most likely, provides depth of
our consciousness.

Our biological hardware is built out of finite atoms. Consciousness unfolds
out of "electrochemical circuits". Electricity == consciousness.

We have what is called "human energy" \- emotions are one example of
expressions out of it.

For AI, to be human like, it has to simulate physical behaviour of human
energy.

I see, that out of this energy behaviour simulations can emerge what I call
"computational psychology". That is, computer could analyze and decode human
behaviour and "understand" like psychologist does this.

Thing is, that many people don't see these subtle patterns - they are learned
over lifetime with different success rates. Once they are aware of these
patterns, they can function more efficiently as a human. Such "psychologist as
app in your pocket" potentially can raise overall quality of society.

~~~
stevenmays
You should read the book On Intelligence by Jeff Hawkins. Pay attention to
Chapter 6, "How the cortex works". Our "consciousness" is derived of the same
stuff in all animals, we just have more cortical layers. We also have fuzzy
algorithms which allow the brain to recognize patterns, and associate x with
y.

[http://www.amazon.com/On-Intelligence-Jeff-
Hawkins/dp/080507...](http://www.amazon.com/On-Intelligence-Jeff-
Hawkins/dp/0805078533)

I think to postulate that there's a yet undiscovered subatomic elementary
particle that gives rise to consciousness is hogwash. "Consciousness" or
awareness of self has been shown in other animals. Humans are distinct in
their ability to couple self-awareness and toolmaking.

There is no "human energy" it's the same material as in all other animals, we
just have more of it. The "human energy" could be classified as distinct fuzzy
algorithms found in humans which aid pattern recognition.

~~~
avera
Not one elementary particle, but whole interaction of many of them.

Yes, animals have that same substance, but at lesser scale.

I make distinction between pure intellect, which computer can do fine, and
other component, which I doubt that it can be accessed by computer without
connecting silicon with biological material.

------
noblethrasher
(1) A computer is anything that does computations, and a computation is just a
set of states that are partially ordered with respect to a “next” state
relation.

(2) A _universal computer_ is a computer that can simulate any other computer
with some bounded slowdown in performance (the actual important thing about
such computers is that they can simulate _better_ computers).

So, while the brain seems to _have_ a universal computer (since it can design
and run universal computers), it’s not obvious that a universal computer can
simulate a brain without infinite slowdown. Some evidence against brains being
equivalent to Universal Turing Machines is that some brains can perceive real
numbers. Thus, it’s conceivable that even if the mind (the thing that is
realized by a brain) is a partially ordered set of states, it’s possible that
the states themselves are not computable.

Now, I am not claiming that we cannot eventually build a brain, just
suggesting that maybe the only thing that can simulate a brain is another
brain.

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guyzero
It's totally a computer! Not like how 99% of the world uses the word
"computer" but it computes things and is vaguely like a FPGA so it's a
computer! Not serial but parallel! Like computers!@ But not parallel like the
computer you have. Like a computer that doesn't actually exist. But it's a
computer!

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gooseyard
An interesting opposing view [http://www.technologyreview.com/view/511421/the-
brain-is-not...](http://www.technologyreview.com/view/511421/the-brain-is-not-
computable/)

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johansch
The only way I can explain the (almost entirely american) backlash at the idea
of the human brain being a computer that we can emulate is that a lot of them
are religious. That is sad.

~~~
return0
In academic circles most of it comes from philosophers of mind, e.g.
[https://en.wikipedia.org/wiki/Hard_problem_of_consciousness](https://en.wikipedia.org/wiki/Hard_problem_of_consciousness)

~~~
johansch
Who in their right mind would go to philosophers to get an understanding on
how the human brain works at a physical level? Why not go to your priest
instead? Same level of understanding.

~~~
Osmium
I think that's somewhat unfair to philosophers. Besides the fact that science
grew out of philosophy, even today philosophers are very good at _defining
problems_ and finding logical inconsistencies. As a scientist, that seems very
useful indeed. To understand the brain on a "physical level", we have to know
what questions we're asking first.

~~~
return0
My experience is that philosophy of mind has almost nothing to offer to modern
neuroscience. The questions being asked are the unhelpful ones and signify a
general obsession with semantics, subjectivity and language tricks.

------
abledon
Hmmm, They don't cover an important fact: Our intestinal microbiome of bugs
that live inside our stomach, affecting our moods and behaviour [1].

[1]
[http://news.nationalgeographic.com/news/2014/11/141114-autis...](http://news.nationalgeographic.com/news/2014/11/141114-autism-
gut-brain-probiotic-research-biology-medicine-bacteria/)

~~~
johansch
I could think of another 10 things that affect humans moods and behavior that
is not mentioned in this article. Your point being?

~~~
abledon
That its an important part of how our brain is influenced in working, and
might have been mentioned in the article to give the reader a better
understanding of underlying mechanisms.

