Current Events > Do brains have a hard limit to how long they can survive?

(+) Yeah! (+)

if we had cloning tech or cyborg tech to replace every part of a body except the brain...how long could someone stay alive? Would the brain eventually start to degrade and break down?

I don't think we really know. There are people who are 110+ years old who are still coherent though, so there's evidence the brain can last a really long time.

Has anyone tried living in a fridge? Things last longer if you store them in the fridge.

Yes, though it depends on the individual and there isn't a hard limit for the species.

BewmHedshot posted...

so there's evidence the brain can last a really long time.

our brains break down overtime. cant last forever :(.

Even in a cyborg body/enclosure that can keep the brain at peak health, oxidative damage and resulting breakdown of cellular structures, like the cytoplasm, will eventually do the brain in.

The best a human body's been able to do is about 125 years. Maybe 150 years max in a cyborg body.

Zikten posted...

if we had cloning tech or cyborg tech to replace every part of a body except the brain...how long could someone stay alive? Would the brain eventually start to degrade and break down?

In this hypothetical, is the brain immune to prions, dementia, hyper intensity, demyelination, etc?

Because I don't think we know the answer to that question. Realistically, the brain would lose function at the same rate that it does in people so it could live a little longer but be generally useless after a human lifespan anyway assuming some other problem didn't kill it.

LinkDaLunatic posted...

Has anyone tried living in a fridge? Things last longer if you store them in the fridge.

Bob Fridge, inventor of the fridge lived in one, that's the whole reason he invented it. He died at the age of 42, exactly three years after he started living in the fridge, after a frozen ham had been put in the fridge to thaw and it fell on his head.

I always figured a brain can only form literally so many neural connections before it can't or you're just deleting things by overwriting old connections. Regardless both are pretty sad ways to live once you reach them.

There's a way to create more neurons for more memories, but...you're gonna hit a cap of how many god damned neurons can be in your head. I guess you could jar it and have even more neurons for your brain in a space like that.

Yes.

https://gamefaqs.gamespot.com/a/forum/8/8f1e1f10.jpg

You basically are born with all the neurons you will ever have (there are some new ones made but they can largely be ignored because they aren't relevant to the actual issue) and you lose them progressively over time. You can see the dramatic drop-off in grey-matter (neurons) with old age, which is also unsurprisingly when you start to see various forms of dementia. All those neurons will die eventually, just like any other cell, and they will not be replaced.

ssjevot posted...

Yes.

https://gamefaqs.gamespot.com/a/forum/8/8f1e1f10.jpg

You basically are born with all the neurons you will ever have (there are some new ones made but they can largely be ignored because they aren't relevant to the actual issue) and you lose them progressively over time. You can see the dramatic drop-off in grey-matter (neurons) with old age, which is also unsurprisingly when you start to see various forms of dementia. All those neurons will die eventually, just like any other cell, and they will not be replaced.

I wonder if somehow science could find a way to make the brain regenerate

at some point i imagine due to evolution, someone is gonna be born with regenerating neurons. how fucked must life be for the first people like that who watch everyone else around them die of old age while they're fine (or worse, not fine since their bodies and brain degrade around them while their neurons are fine)

Zikten posted...

I wonder if somehow science could find a way to make the brain regenerate

You would have to get rid of all the scar tissue too somehow. I've seen a lot of brains from people who died of various neurodegenerative diseases and the scar tissue takes up the space those neurons used to be in. The formation of this tissue actually causes more damage despite it being your body's response to damage. But anyway, there's no way any of this is happening anytime soon. You would need some kind of sci-fi nanotechnology. Anything outside biology isn't my specialty, so I can't comment on that. As far as biology is concerned though, no, there's no realistic proposal that could regenerate the lost tissue.

Rika_Furude posted...

at some point i imagine due to evolution, someone is gonna be born with regenerating neurons. how fucked must life be for the first people like that who watch everyone else around them die of old age while they're fine (or worse, not fine since their bodies and brain degrade around them while their neurons are fine)

That's not how evolution works. If you pass your genes on that's all that matters. There's no incentive for a human to live longer than they already do in terms of increasing the chances of passing on your genes and a random mutation that made you able to regenerate neurons (even outside the absurdity of this happening) wouldn't make you more likely to pass your genes on.

ssjevot posted...

That's not how evolution works. If you pass your genes on that's all that matters. There's no incentive for a human to live longer than they already do in terms of increasing the chances of passing on your genes and a random mutation that made you able to regenerate neurons (even outside the absurdity of this happening) wouldn't make you more likely to pass your genes on.

There's no incentive for anything. It's just random mutations, and whatever gets passed on gets passed on right? Evolution isn't guided/intentional.

Rika_Furude posted...

There's no incentive for anything. It's just random mutations, and whatever gets passed on gets passed on right? Evolution isn't guided/intentional.

The genes that get passed on are those that contribute to fitness. That's what natural selection refers to. Evolution won't cause humans to develop regenerating brains, because such a mutation isn't beneficial to passing on genes for humans (this is ignoring how extremely unlikely the mutations necessary for that to happen would all occur in a person to begin with). It's like how some animals have ways to regenerate the hair cells in their ears, but humans don't (which means we accumulate hearing damage over time and lose our hearing as we age). Because severe hearing damage in humans tends to occur well past the age when it would matter for passing on our genes for most people, this type of trait never evolved in humans. However for some animals this type of mutation was beneficial enough to passing on their genes that it became a trait (some fish and birds mainly).

Rika_Furude posted...

There's no incentive for anything. It's just random mutations, and whatever gets passed on gets passed on right? Evolution isn't guided/intentional.

https://gamefaqs.gamespot.com/a/forum/2/2fef1f1d.jpg

He's particularly interesting in that all his kids are IVF and they were using the latest technology to select embryos believe to have "the best" genes. It's definitely not the way natural selection has been occurring up until now and although it's not quite the designer babies thing that Chinese scientist that got jailed was doing, but it's basically a step in that direction. I can't really say much about what implications this type of stuff has, but yeah. Interesting (not necessarily in a good way).

ssjevot posted...

That's not how evolution works. If you pass your genes on that's all that matters. There's no incentive for a human to live longer than they already do in terms of increasing the chances of passing on your genes and a random mutation that made you able to regenerate neurons (even outside the absurdity of this happening) wouldn't make you more likely to pass your genes on.

Living longer would be an advantage in men in the sense that the longer you live, the more time you have to pass on your genes.

Despite what's been said, no.

The amount of neurons in your brain doesn't increase, HOWEVER, connections between neurons absolutely increases as well as the "shealthing" around connections. Your brain definitely does "grow" because freaking of course it does.

The number of cells might not increase but you can grow "tendrils" to other braincells or also a connection can fade and even get severed.

I like the cyborg body idea... i think 150 years easy and probably more than that, to be honest.

Turtles live for 200+ years and seem fine. We should be able to keep a brain alive and functioning for that long at least.

if we could digitize a brain then you could live for 1000s of years, or "forever."

I assume yes that is why dementia is a thing

Then again turtles can live hundreds of years

rick_alverado posted...

Living longer would be an advantage in men in the sense that the longer you live, the more time you have to pass on your genes.

It wouldn't be much of an advantage because sperm quality drops off with age too. And the ability to attract fertile women goes down with age for the vast majority of men as well. If living longer was a significant advantage the people with genes for living longer would have come to be predominant and people with diseases that cause you to die at a young age (such as Huntington's disease) would have been out-competed. But since the vast, vast majority of humans were (and still are) created by teen to young adult aged people this never came to be.

Robot2600 posted...

The amount of neurons in your brain doesn't increase, HOWEVER, connections between neurons absolutely increases as well as the "shealthing" around connections. Your brain definitely does "grow" because freaking of course it does.

No it doesn't in the long term. Look at that chart again. White matter decreases with age too. That's the myelin sheath.

LinkDaLunatic posted...

Has anyone tried living in a fridge? Things last longer if you store them in the fridge.

Didn't work for Green Lanterns girl

Robot2600 posted...

Despite what's been said, no.

The amount of neurons in your brain doesn't increase, HOWEVER, connections between neurons absolutely increases as well as the "shealthing" around connections. Your brain definitely does "grow" because freaking of course it does.

The number of cells might not increase but you can grow "tendrils" to other braincells or also a connection can fade and even get severed.

Any long term growth experienced by the brain is rapidly outpaced by demyelination, dementia, and other problems.

While the brain can live longer than the rest of the body, it will eventually die unless you have some magic way to prevent brain damage.

Tyranthraxus posted...

Any long term growth experienced by the brain is rapidly outpaced by demyelination, dementia, and other problems.

While the brain can live longer than the rest of the body, it will eventually die unless you have some magic way to prevent brain damage.

There's this sort of secular after-life belief that people are increasingly having where you can just get a robot body, gene-therapy, or upload your "mind" (literally just a copy, please think for a second people) and then you live forever. Replacing religion with science magic to serve the same function (alleviate fear of death).

ssjevot posted...

There's this sort of secular after-life belief that people are increasingly having where you can just get a robot body, gene-therapy, or upload your "mind" (literally just a copy, please think for a second people) and then you live forever. Replacing religion with science magic to serve the same function (alleviate fear of death).

I've always said simulation theory is basically just another religion except God is a computer.

ssjevot posted...

upload your "mind" (literally just a copy, please think for a second people)

Sounds like they're trying to think for a second person, honestly.

Zikten posted...

I wonder if somehow science could find a way to make the brain regenerate

Neurogenesis is a thing, but to my understanding it is on such a small scale that it is basically irrelevant.

Also good to know: the longer a brain goes without oxygen, the bigger chance of longterm damage. This is why administering oxygen (through mouth-to-mouth or mechanical ventilation) is a crucial part of CPR. Basically if the brain has no oxygen for 7 minutes or more, even if the body survives, it's likely that person will remain in a vegetative state.

PurestProdigy posted...

Neurogenesis is a thing, but to my understanding it is on such a small scale that it is basically irrelevant.

This covers it pretty well, but basically it's essentially none to a small enough amount that it doesn't matter. I mentioned it in my first post because people always bring it up, but it's really not relevant to the issue which is why you see people at age 100 with on average 65% of the grey matter volume they had at their peak. Whatever amount is happening is so small that it can't offset the massive amount of loss in comparison (it's also primarily localized to the hippocampus, not helpful for major neurodegenrative diseases that occur elsewhere or just the practical distributed loss of neurons over time).
https://en.wikipedia.org/wiki/Adult_neurogenesis

new research is showing some brains peaking at 60.

im not even disputing that that chart is accurate and that's the average. but i think people stop thinking, learning and growing as a choice much of the time. society is structured to make it almost inevitable, but it's obvious it doesn't have to happen. plenty of people in their 90s are sharp.

Alright man. You choose to live forever and have your brain be awesome. Let us know how it goes. There have been actively working professors who get dementia. I have even known some. They certainly didn't choose to stop learning since that was their job, but you have made it obvious you know more than professors in this topic, so best of luck to you.

Robot2600 posted...

new research is showing some brains peaking at 60.

im not even disputing that that chart is accurate and that's the average. but i think people stop thinking, learning and growing as a choice much of the time. society is structured to make it almost inevitable, but it's obvious it doesn't have to happen. plenty of people in their 90s are sharp.

I don't really see what choosing to stop learning has anything to do with the topic at hand. This is about the longevity of Krang if Krang was a human brain. You can't choose to give yourself dementia.

Robot2600 posted...

new research is showing some brains peaking at 60.

im not even disputing that that chart is accurate and that's the average. but i think people stop thinking, learning and growing as a choice much of the time. society is structured to make it almost inevitable, but it's obvious it doesn't have to happen. plenty of people in their 90s are sharp.

I think it's more genetics than choice. Brains degrade over time. My great aunt was a smart business woman and sharp until around 90, then quickly her brain started slipping.

I don't see why that wouldn't happen if put in a robot body. Our brain cells and neurons just give out over time. We can stop it just as much as we can stop wrinkles from forming.