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  • Someday our bodies are going to break down and we'll die.

  • 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 saydownloading 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!

  • Let us know in the comments what topics you want us to cover in future episodes.

  • And if you want more How Close Are We, click here to watch our playlist.

  • And don't forget to like, share, and subscribe.

Someday our bodies are going to break down and we'll die.

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我们离下载人脑有多近?(How Close Are We to Downloading the Human Brain?)

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    joey joey 發佈於 2021 年 04 月 16 日
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