Your Brain as Math - Part 1 | Infinite Series

What does your brain look like when it's broken down mathematically? And what can this tell us? This is Part 1 in our Your Brain as Math mini-series.

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Stochastic Supertasks

In order to dive deeper into an exciting topic, we're mixing up the format. Over the next three days, we’ll spend the next three episodes exploring an incredible application of seemingly purely-abstract mathematics: how algebraic topology can help us decode the connections among neurons in our brains, to help us understand their function.

Written and Hosted by Kelsey Houston-Edwards
Produced by Rusty Ward
Graphics by Ray Lux
Assistant Editing and Sound Design by Mike Petrow

Resources:

Cliques of Neurons Bound into Cavities Provide a Missing Link between Structure and Function

The Blue Brain Project

Barcodes: The Persistent Topology of Data

Network Neuroscience

Algebraic Topology

Special thanks to Kathryn Hess and Florian Frick!

Comments answered by Kelsey:

Vriskanon

Challenge Winner : Florence B

Special thanks to Matthew O'Connor and Yana Chernobilsky who are supporting us on Patreon at the Identity level!

And thanks to Mauricio Pacheco who is supporting us at the Lemma level!

[MegaAwesomeNick]

This is your brain *holds egg*, this is math *holds frying pan*, this is your brain as math *fries egg*. Any questions?

[charlesrosenbauer]

There's a company called Numenta that is trying to reverse-engineer the brain. It turns out that almost every part of the cortex is structured almost identically to every other. The only difference (with a few exceptions) is that the different cortical regions get different inputs.

Their theory is called Hierarchical Temporal Memory if anyone is interested, and the math behind it involves a lot of sparse binary vectors and combinatorics. Plus, from what I've heard, a lot of people at the Blue Brain project are starting to take it seriously.

[dragoncurveenthusiast]

2:57 "There are serious neuroscientific questions about the legitimacy or accuracy of this reconstructed brain. It's controversial"
As a neuroscientist I have to say: Thank you for mentioning this! I am one of those who think it will do more to help us develop computers than it will do in understanding our brain. From a neuroscientific perspective I think it's a huge waste of money.

Also: I know everything has to be simplified, but a directed graph would be much better and is also well described mathematically as far as I know. Then, adding different strengths/weights to the connections would be a giant leap in making it more realistic. At that point it would get close enough to reality to make not only the math interesting, but also the conclusions and their biological consequences for the brain!

[jameswise]

You are objectively one of the best youtubers on youtube, thank you for being with us.

[vitormedeiros]

Part 1? Oh boy, that's going to be an _infinite series_

[oker]

I heard about this high dimensional topology of the brain . . . somewhere. I'm glad to see a presentation of it here.

- A brain has millions of myelin. They modulate nervous system electrical activity like resistors. Many are placed as one grows up(becomes conditioned). But, they also get placed on neurons while learning. I think of this as suggesting that the Brain is a kind of muscle. Use it or loose it.

[AMcAFaves]

Im looking forward to this series. It's exciting!

[alihesham]

a person studying about brains
is just a brain trying to understand itself

[bronylike]

i have a good idea for a vid.
you add numbered balls to a box.
for each number, you remove the factors of that number, except for one and its self
if a factor of a number has been removed already then you are to put it back into the box
what would the sequence look like for the number of balls in the box

[AFastidiousCuber]

Does anyone else find discussions of the brain to be really existentially disturbing? I think it has to do with the realization that what I perceive as "me" is merely a series of mathematically describable processes behaving deterministically, and "I" am not uniquely different from any inanimate object, except in terms of relative complexity.

[xaostek]

This is your brain.

And this is your brain on math.

[mrfatmancory]

"your brain is physically 3 dimensional"
Ok so she's going to use a 2 dimensional chart of some kinda to showcase connections or something
"11 dimensions"
(*ﾟﾛﾟ)

[YuzuruA]

11 dimensions? Next thing you know she will use string theory...

[jbrowsingj]

so excited to watch the rest of these!

[TiKayStyle]

Perfect topic! Last weekend I heared about it. I am looking forward!

[jimtuv]

I have been having trouble learning topology. I am excited about the next video.

[absiddi.]

Can I just say how absolutelu STUNNING the host is? Drop dead gorgeous and also extremely intelligent. 🙌👩🏼

[EdwardNavu]

Woah. You cosmology enthusiasts need to calm down. Our brain is still inside the good ol' 3+1D spacetime, not a higher dimensional objects physically. It's just that we used higher dimensional abstract shapes in order to visualize brain connections in a better and tidier way.

[purplelink]

The intro of this video has too much power

[zmail]

Isn't there an issue in seeing a neuron as a point or a binary "on and off" switch? The neuron itself is quite complex, I'd say, and the operation needs to be defined in a much more rigorous way, each particular neuron might seem insignificant in a rat or a human, but in an insect or simpler life forms, neurons seem to be something much more complex as they are fewer in number but yet are able to give rise to some form of "life" (for instance the "Caenorhabditis elegans" which has 300 neurons). My point here is, the issue should not necessarily be "mapping", similarly to how understanding anatomy does not give one understanding of how it is that muscles can operate for instance, understanding neurons will not necessarily give us information about the operation of the neuron or neurons.
Anatomy gave us a map of body parts.
Mapping neurons will simply give us a map of neurons for all i know.

Is this unreasonable skepticism?