Our brain will decay and disappear forever.But, what if it didn't have to?

Right now there are scientists around the world working on technology that could one

day take your brain, and possibly your consciousness, and upload it onto a computer.

This would be a game changer in neuroscience and some believe could lead to immortality.

So, how close are we to downloading our brains?

Okay first off, what do we mean when we say “downloading the brain?”

It's not plugging a cable into your head and syncing it with your phone.

It is much more complicated than that because, well, the brain is really, really complicated.

The information in a brain is encoded in the synaptic connections between neurons.

This is the major theory of how not only episodic memories are encoded in the brain, but essentially

all learned knowledge, // Now, there's on the order of 100 billion neurons in a human

brain and each of those neurons has tens of thousands of connections.

You are looking at hundreds of trillions of those synaptic connections, each of which

have been tuned by your life's experience.

So in order to download your brain, each one of those trillions of connections would have

to be precisely scanned, mapped and digitally reconstructed on a computer as an emulated

brain.

The idea would be, that this simulation would not only behave like a biological brain, but

could retain the thoughts and memories of the person whose brain was scanned.

Now, all this is great to think about and makes for interesting dinner conversation,

but we have yet to scan a complete human brain let alone test the theory of consciousness.

That's not to say some progress hasn't been made though.

There are projects all over the world working on scanning and simulating brains in the name

of healthcare and medicine.

This is more about unlocking mysteries of our brain and less about unlocking the key

to immortality.

...we don't really understand a system until we can build it ourselves and manipulate it

in a computer, and really understand all the pieces and parts.

In 2014, researchers scanned a roundworm brain and made a simulation that they installed

into a simple Lego robot.

And, the simulated brain moved the robot freely without any human direction.

There have been other projects trying to recreate the brain through reverse engineering, experiments

reading and implanting memories and one group created an algorithm for large scale human

brain simulations.

But one of the biggest projects involving actual brain scanning is taking place at the

Allen Institute in Seattle.

They have scanned and digitally reconstructed a cubic millimeter of a mouse brain.

Yes, this may not seem like a big deal due to the small scale, but this is the largest

roadmap of connections of a mammalian brain ever.

Now, a cubic millimeter is about the size of a single grain of sand and is home to 100,000

neurons and over a billion synapses.

In order to scan this tiny segment, it first had to be sectioned 25,000 with each slice being about a fifth the thickness

of a human hair. were taken. Then 10s of millions of images were taken. This gives you an idea of what

would need to happen to scan an entire human brain.

That means that mapping a human brain, a million times larger, would take a fleet of electron

microscopes decades in order to image.

Obviously the technology is going to have to change.

Perhaps not radically but at least in scale to make something like this happen.

We just don't have powerful enough microscopes to be able to accurately and efficiently image

entire human brain.

And even if we could, the question would still remain; if we could copy our brain, would

that also copy our consciousness?

Most neuroscientists would say yes, it's exactly the same person if it's exactly the same thing,

but we really don't know if there's some other issue that we're missing.

// Still the question is, is the simulation at a resolution that is sufficient to capture

who you are?

The idea is that our thoughts and memories are basically data, and in theory we should

be able to copy that data over to a computer and you'd still be you.

But, what kind of you?

...if we made a replication of your brain, there's no reason that you'd be living in

silence and darkness inside Dropbox.

We'd be giving you fake input.

In theory, if somebody were a computer simulation // what it would be like is exactly what this

is like for us.

You'd look around, you'd say, "Here I am, I can feel my body, I can taste this drink,

I can eat this pizza," and it in theory wouldn't be any different.

Or if you want to still experience the real world, your brain could be installed into

a robot.

The person opens up their robotic eyes, and they say, "Wow, I'm still here."

If it works, that's how it should feel.

It should feel like you are coming out of a surgery and you should be able to call up

memories from your past, you should be able to still remember how to do certain things,

you should have the same likes and dislikes...

However, advancements in connectomics won't come from scientists looking for the fountain

of youth.

Researchers want to understand the brain better in order to combat disease and mental disorders.

We'd be able to better treat tumors, epilepsy, addiction and learn more about how we evolved.

This is why people are looking to digitally map the brain.

In the end, if we are ever able to upload someone's consciousness, it may just be

a bonus to these studies.

Mind uploading is a very long-term project of humanity.

It's so long-term that I think most of the people today that are working on it would

not recognize that they're working on it.

The desire is there to scan and map an entire human brain.

That process may lay the groundwork for a brave volunteer to have their brain removed

and digitized which might lead to the first immortal being.

We just have to wait for technology to catch up with our ambition.

So, how close are we to downloading the human brain?

We're nowhere close.

We can't even download a fruit fly....

We can image small pieces of brain tissue, or small organisms brains.

But, we don't know enough about how the nervous system works in order to interpret those images

and create a simulation of that.

With the technology the we have right now, we're nowhere close.

But the road seems clear enough to get there, unless there's some giant surprise that we

run into.

It seems like each year as technology gets better and better, we get higher and higher

resolution on what's going on.

It's a clear path to get there.

I mean, unless we already are there and you are currently watching this in a computer

simulated world where nothing around you really exists.

Thanks for watching How Close Are We!

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