7 ms·

The cell damage inflicted by the cryo process is readily acknowledged by its proponents. They argue that the neurological damage is not so large that the origin

by gizmo 14y ago

The cell damage inflicted by the cryo process is readily acknowledged by its proponents. They argue that the neurological damage is not so large that the original brain can't be reconstructed either by scanning it while still frozen or by repairing it with nano-bots. Much like data from a wiped hard drive can still be recovered by digital forensics. As for the problem of outer layers freezing faster than inner layers, I think this is mostly addressed by filling the brain with anti-freeze first. Now, I'm rather skeptical of the whole process myself, but the crynoics guys understand biology 101.

justincormack 14y ago
No they understand how to fleece gullible people.
- Filligree 14y ago
  Including themselves? They're not making any money off this, Alcor is a non-profit and the wages of the personnel involved are fairly low.
mryan 14y ago
> ... is not so large that the original brain can't be reconstructed either by scanning it while still frozen or by repairing it with nano-bots. You might as well argue that nano-bots will be able to reanimate a body that has decomposed, and save money on all the freezing equipment. Perhaps that will be the case if given enough time, but we seem to be a long way away from that technology. The business model seems to be "give us money now, and the technology that could make this work will probably be invented soon enough. Probably".
- nawitus 14y ago
  >You might as well argue that nano-bots will be able to reanimate a body that has decomposed, and save money on all the freezing equipment. Perhaps that will be the case if given enough time, but we seem to be a long way away from that technology. No, you might not as well argue that. If you think you can, then please argue how you can retrive information from a completely decomposed brain. On the other hand, it's pretty reasonable to assume that a cryopreserved brain preserves a lot of the information in the brain.
  - alphaoverlord 14y ago
    Why is it reasonable to assume that? Its fiat on both examples and both examples currently are impossible.
  - mryan 14y ago
    alphaoverlord understands the point I was making. Both of these things are impossible, at the current level of tech. One or both of them might become possible through the use of sufficiently advanced technology. > On the other hand, it's pretty reasonable to assume that a cryopreserved brain preserves a lot of the information in the brain. See, I don't think it's reasonable to assume this. I believe that both of these things are equally possible - that is, not very possible at all.
    - nawitus 14y ago
      >I believe that both of these things are equally possible - that is, not very possible at all. I believe it's incorrect to claim that the probability that a cryopreserved brain has some information about the brain structure is equal the the probability that a fully decomposed brain has after decades of decomposing (which is the scenario I have in mind). I just don't understand how someone could make such a proposition. If we dig up a decomposed brain, it's just pretty much completely destroyed (e.g. fully decomposed) if we look at it with a microscope. I'm assuming that we're not talking about rare niche cases of fossilization etc. To have an idea of how much information vitrification preserves, you should know that a kidney can be frozen and thawed, and replanted to a live animal. We can also look at neural tissue after vitrification, like here: http://www.alcor.org/Library/html/braincryopreservation1.html http://www.alcor.org/Library/html/braincryopreservation1.htm... After you've looked at this probably new evidence presented to you, do you still seriously claim that it's exactly equally as possible to retrive information from a cryopreserved brain as it is from a decomposed brain? I don't believe you actually think that. I think that you've made the mistake to take two extremely unequal yet different and small probabilities to mean exactly the same. If you assume that the probability that cryopreservation is 0.1%, then you should think that the probability to retrieve information from a decomposed brain to be lower than 0.001%. They're both really small, but they're not unequal. Do you think that the probability is exactly the same? I rate such beliefs as not only wrong, but ignorant of empirical evidence.
nnq 14y ago
They don't! If someone could freeze at least a small insect brain after it "learned something", unfreeze it and prove that it retained what it learned, I might have at least a grain of faith in this. Even getting an insect ganglia out on a feeder plate with electrodes, training it to respond in a way to a certain sequence of input electrical impulses and proving that after thawing and reanimation it still preserves that memory would light a spark of faith, but we don't even have this! Understanding "biology 101" means understanding that biology is about experiments, everyth is empirical (and will be for quite some time I guess), nothing can be said that "it works" in biology or medicine until you experimentally prove it does. Maybe in a few centuries we'll have cool equations describing life and have something like "theoretical biology" that will be like theoretical physics is to physics (no, what we call "theoretical biology" nowadays is not that!). Show me some equations (derived from experiments, of course, and that can predict other experiments of course) describing the amount of information relevant to a human's personality that can be recovered from a frozen brain! If you can't, prove it experimentally. If you can't... bad luck! With the kinds of probabilities involved in biology, "good things" (like being lucky to be able to revive a frozen human brain) don't happen by chance! "Nature"/"The universe"/"God" is NOT on our side on this path, so there's no room for optimistic thinking, we can only rely on cold (literally) hard science and math!
- nawitus 14y ago
  So your argument is that until it's "proven" that we can cryopreserve and then restore brains, the probability of success is zero? If you agree that the probability is non-zero, then you agree with the cryopreservation advocates. In addition, if you agree that it's non-zero, you must agree that it's better than doing nothing (which clearly has a zero chance of revival). Cryopreservation advocates do not claim that the process is proven to be work, they claim that the chance may be small, but it's non-zero. >"Nature"/"The universe"/"God" is NOT on our side on this path, so there's no room for optimistic thinking, we can only rely on cold (literally) hard science and math! I don't even know where you're going with this discourse. If you're a utilitarian rationalist you can estimate the chance of success for cryopreservation and revival. It's quite easy to show that if the probability is non-zero, then it's beneficial to make such a bet, as the possible positive utility can be huge if the cryopreservation is succesful. If you think that probability estimates are "not science" and therefore "irrational", you don't know what you're talking about. If you think that current scientific evidence shows that the chance of revival is zero, then you're clearly wrong (and that would contradict your own claims, as zero chance would mean there's no need to make any new experiments).
solox3 14y ago
That's complete nonsense. Nanobots cannot repair angstrom-scale freeze damages. You approach the classical limit, where protons are more wave than particle. And what's a brain antifreeze? Even biocompatible antifreeze proteins found in arctic oceans have a thermal threshold of 269K, which is no where near cryogenic temperature.
- khafra 14y ago
  Angstrom-scale fidelity may not be necessary for preserving memories/personality/identity. The antifreeze they use is neurotoxic, which is a known problem.
- nawitus 14y ago
  Have you read this? http://www.alcor.org/Library/html/braincryopreservation2.html http://www.alcor.org/Library/html/braincryopreservation2.htm...
- lsparrish 14y ago
  > Nanobots cannot repair angstrom-scale freeze damages. Vitrification avoids ice. Nanobots could e.g. remove toxic compounds from extracellular areas and replace them with nontoxic solutions, and deliver yet-to-be-invented drugs that would activate upon thawing. > Even biocompatible antifreeze proteins found in arctic oceans have a thermal threshold of 269K, which is no where near cryogenic temperature. The stuff invented by 21st Century Medicine and used to successfully cryopreserve a rabbit kidney is a combination of the ordinary kind of penetrating antifreeze that depresses the freezing point (glycerol, EG, DMSO, and the like) with polymers that inhibit ice nucleation (functionally similar to antifreeze proteins). It has been known for a while that you can vitrify slowly by using high concentrations of the former kind of solute (depress the freezing temperature to below the glass transition temperature and the cooling rate no longer matters) but the latter lets you get away with somewhat more water in the mix, is my understanding. There's a tradeoff when you cool things, where if you get cold enough it slows toxicity. They don't perfuse with the stuff until the brain is already cooled to near 0 degrees C, and it is ramped in concentration over time to prevent osmotic shock.
hp50g 14y ago
The brain is like flash memory. Sure some of the conent is still possible to get at (electrical charge stays around for a long time) but the circuits between the flash cells are all dead. The connections are as important as the state. Not going to happen.
- nawitus 14y ago
  Alcor FAQ states this: “We know that secondary memory does not depend on continued activity of the nervous system, because the brain can be totally inactivated by cooling, by general anesthesia, by hypoxia, by ischemia, or by any method, and yet secondary memories that have been previously stored are still retained when the brain becomes active once again. Therefore, secondary memory must result from some actual alterations of the synapses, either physical or chemical.” — Textbook of Medical Physiology by Arthur C. Guyton (W.B. Saunders Company, Philadelphia, 1986), page 658. “Procedural and declarative memories differ dramatically. They use a different logic (unconscious vs. conscious recall) and they are stored in different areas of the brain. Nevertheless, these two disparate memory processes share several molecular steps and an overall molecular logic. Both are created in at least two stages: one that does not require the synthesis of new proteins and one that does. In both, short-term memory involves covalent modification of preexisting proteins and changes in the strength of preexisting synaptic connections, whereas long-term memory requires the synthesis of new proteins and the growth of new connections. Moreover, both forms of memory use PKA, mitogen-activated protein kinase (MAPK), CREB-1, and CREB-2 signaling pathways to convert short-term to long-term memory. Finally, both forms appear to use morphological changes at synapses to stabilize long-term memory.” — “Synapses and Memory Storage” by Mayford M, Siegelbaum SA, and Kandel ER. Cold Spring Harbor Perspectives in Biology, April 10, 2012, page 10.
  - hp50g 14y ago
    Yes but freezing the damn thing fucks the dendrites up completely. The nervous system is dead.
roc 14y ago
If the concept only works when we're relying on full-brain scans and future nano-bots with the capability to reconstruct brain tissue, the freeze/thaw would be completely superfluous. Why not cut out the middle-man? Just do a full brain scan and store the digital data until the nano-bots arrive? Then just recreate brains within stock bodies or some virtual/machine environment? Clinging to the freezing and thawing, when you're forced to concede they won't actually work and then having to invent far superior technologies, but only applying them as a band-aid over the broken technology, looks an awful lot more like someone with a belief grasping for intellectual cover, rather than someone with an intellectual understanding positing solutions.
- khafra 14y ago
  > Just do a full brain scan and store the digital data until the nano-bots arrive? Because we don't currently have the technology to either scan or store a 3-d scan of your brain in the same resolution you can get by physically perfusing it with antifreeze and dropping it into a bucket of liquid nitrogen.
  - roc 14y ago
    But by the time you've physically perfused the brain and frozen it, substantial cell death would have begun. So if we have to freeze until the scanning/storage tech arrives, we'll have a compromised source, at best.
    - khafra 14y ago
      Yes. Whether or not the most substantial damage occurs with apoptosis when oxygen is re-introduced, there will uncontroversially be a lot of damage even in the best case cryonic vitrification. Also uncontroversially, there will be substantially less damage than would occur with cremation or burial. Even the lesser amount of damage may be too much. Cryonics is a bet that it is not.
      - roc 14y ago
        But is there a scientific basis to prefer this bet to, say, death-bed religious conversion?
primitur 14y ago
Science Fiction != Science! (Yet.)
jellicle 14y ago
> Now, I'm rather skeptical of the whole process myself, but the crynoics guys understand biology 101. Actually, they mostly understand Psychology 101, which is that people are willing to pay unlimited amounts of money for the promise of life after death. SEE ALSO: turning lead into gold.
- Jach 14y ago
  If they really wanted to scam people, there are far better ways than suckering a couple thousand people out of membership dues, and a couple hundred people out of leaving their $30k - $200k (hardly unlimited, especially for software developers!) life insurance payout to a family member.
  - afterburner 14y ago
    There's always another way to skin a cat, but you get good at one way and keep at it.
- FeepingCreature 14y ago
  http://www.alcor.org/cryomyths.html http://www.alcor.org/cryomyths.html > Alcor has no company owners to profit from cryonics, salaries are modest, and the Board of Directors serves without pay.
- davidgerard 14y ago
  Cryonicists are, generally, painfully sincere. This is not the same as correct, of course. http://rationalwiki.org/wiki/Cryonics http://rationalwiki.org/wiki/Cryonics
snowwrestler 14y ago
Data on a hard drive can be recovered precisely because a typical deletion does not destroy any data--only the addressing bits are erased. If you take a HD and write over half the bits with zeroes, you will not be recovering much useful information from that with digital forensics.

by gizmo 14y ago

justincormack 14y ago

No they understand how to fleece gullible people.

Filligree 14y ago
Including themselves? They're not making any money off this, Alcor is a non-profit and the wages of the personnel involved are fairly low.

mryan 14y ago

> ... is not so large that the original brain can't be reconstructed either by scanning it while still frozen or by repairing it with nano-bots. You might as well argue that nano-bots will be able to reanimate a body that has decomposed, and save money on all the freezing equipment. Perhaps that will be the case if given enough time, but we seem to be a long way away from that technology. The business model seems to be "give us money now, and the technology that could make this work will probably be invented soon enough. Probably".

nawitus 14y ago
>You might as well argue that nano-bots will be able to reanimate a body that has decomposed, and save money on all the freezing equipment. Perhaps that will be the case if given enough time, but we seem to be a long way away from that technology. No, you might not as well argue that. If you think you can, then please argue how you can retrive information from a completely decomposed brain. On the other hand, it's pretty reasonable to assume that a cryopreserved brain preserves a lot of the information in the brain.
- alphaoverlord 14y ago
  Why is it reasonable to assume that? Its fiat on both examples and both examples currently are impossible.
- mryan 14y ago
  alphaoverlord understands the point I was making. Both of these things are impossible, at the current level of tech. One or both of them might become possible through the use of sufficiently advanced technology. > On the other hand, it's pretty reasonable to assume that a cryopreserved brain preserves a lot of the information in the brain. See, I don't think it's reasonable to assume this. I believe that both of these things are equally possible - that is, not very possible at all.
  - nawitus 14y ago
    >I believe that both of these things are equally possible - that is, not very possible at all. I believe it's incorrect to claim that the probability that a cryopreserved brain has some information about the brain structure is equal the the probability that a fully decomposed brain has after decades of decomposing (which is the scenario I have in mind). I just don't understand how someone could make such a proposition. If we dig up a decomposed brain, it's just pretty much completely destroyed (e.g. fully decomposed) if we look at it with a microscope. I'm assuming that we're not talking about rare niche cases of fossilization etc. To have an idea of how much information vitrification preserves, you should know that a kidney can be frozen and thawed, and replanted to a live animal. We can also look at neural tissue after vitrification, like here: http://www.alcor.org/Library/html/braincryopreservation1.html http://www.alcor.org/Library/html/braincryopreservation1.htm... After you've looked at this probably new evidence presented to you, do you still seriously claim that it's exactly equally as possible to retrive information from a cryopreserved brain as it is from a decomposed brain? I don't believe you actually think that. I think that you've made the mistake to take two extremely unequal yet different and small probabilities to mean exactly the same. If you assume that the probability that cryopreservation is 0.1%, then you should think that the probability to retrieve information from a decomposed brain to be lower than 0.001%. They're both really small, but they're not unequal. Do you think that the probability is exactly the same? I rate such beliefs as not only wrong, but ignorant of empirical evidence.

nnq 14y ago

They don't! If someone could freeze at least a small insect brain after it "learned something", unfreeze it and prove that it retained what it learned, I might have at least a grain of faith in this. Even getting an insect ganglia out on a feeder plate with electrodes, training it to respond in a way to a certain sequence of input electrical impulses and proving that after thawing and reanimation it still preserves that memory would light a spark of faith, but we don't even have this! Understanding "biology 101" means understanding that biology is about experiments, everyth is empirical (and will be for quite some time I guess), nothing can be said that "it works" in biology or medicine until you experimentally prove it does. Maybe in a few centuries we'll have cool equations describing life and have something like "theoretical biology" that will be like theoretical physics is to physics (no, what we call "theoretical biology" nowadays is not that!). Show me some equations (derived from experiments, of course, and that can predict other experiments of course) describing the amount of information relevant to a human's personality that can be recovered from a frozen brain! If you can't, prove it experimentally. If you can't... bad luck! With the kinds of probabilities involved in biology, "good things" (like being lucky to be able to revive a frozen human brain) don't happen by chance! "Nature"/"The universe"/"God" is NOT on our side on this path, so there's no room for optimistic thinking, we can only rely on cold (literally) hard science and math!

nawitus 14y ago
So your argument is that until it's "proven" that we can cryopreserve and then restore brains, the probability of success is zero? If you agree that the probability is non-zero, then you agree with the cryopreservation advocates. In addition, if you agree that it's non-zero, you must agree that it's better than doing nothing (which clearly has a zero chance of revival). Cryopreservation advocates do not claim that the process is proven to be work, they claim that the chance may be small, but it's non-zero. >"Nature"/"The universe"/"God" is NOT on our side on this path, so there's no room for optimistic thinking, we can only rely on cold (literally) hard science and math! I don't even know where you're going with this discourse. If you're a utilitarian rationalist you can estimate the chance of success for cryopreservation and revival. It's quite easy to show that if the probability is non-zero, then it's beneficial to make such a bet, as the possible positive utility can be huge if the cryopreservation is succesful. If you think that probability estimates are "not science" and therefore "irrational", you don't know what you're talking about. If you think that current scientific evidence shows that the chance of revival is zero, then you're clearly wrong (and that would contradict your own claims, as zero chance would mean there's no need to make any new experiments).

solox3 14y ago

That's complete nonsense. Nanobots cannot repair angstrom-scale freeze damages. You approach the classical limit, where protons are more wave than particle. And what's a brain antifreeze? Even biocompatible antifreeze proteins found in arctic oceans have a thermal threshold of 269K, which is no where near cryogenic temperature.

khafra 14y ago
Angstrom-scale fidelity may not be necessary for preserving memories/personality/identity. The antifreeze they use is neurotoxic, which is a known problem.
nawitus 14y ago
Have you read this? http://www.alcor.org/Library/html/braincryopreservation2.html http://www.alcor.org/Library/html/braincryopreservation2.htm...
lsparrish 14y ago
> Nanobots cannot repair angstrom-scale freeze damages. Vitrification avoids ice. Nanobots could e.g. remove toxic compounds from extracellular areas and replace them with nontoxic solutions, and deliver yet-to-be-invented drugs that would activate upon thawing. > Even biocompatible antifreeze proteins found in arctic oceans have a thermal threshold of 269K, which is no where near cryogenic temperature. The stuff invented by 21st Century Medicine and used to successfully cryopreserve a rabbit kidney is a combination of the ordinary kind of penetrating antifreeze that depresses the freezing point (glycerol, EG, DMSO, and the like) with polymers that inhibit ice nucleation (functionally similar to antifreeze proteins). It has been known for a while that you can vitrify slowly by using high concentrations of the former kind of solute (depress the freezing temperature to below the glass transition temperature and the cooling rate no longer matters) but the latter lets you get away with somewhat more water in the mix, is my understanding. There's a tradeoff when you cool things, where if you get cold enough it slows toxicity. They don't perfuse with the stuff until the brain is already cooled to near 0 degrees C, and it is ramped in concentration over time to prevent osmotic shock.

hp50g 14y ago

The brain is like flash memory. Sure some of the conent is still possible to get at (electrical charge stays around for a long time) but the circuits between the flash cells are all dead. The connections are as important as the state. Not going to happen.

nawitus 14y ago
Alcor FAQ states this: “We know that secondary memory does not depend on continued activity of the nervous system, because the brain can be totally inactivated by cooling, by general anesthesia, by hypoxia, by ischemia, or by any method, and yet secondary memories that have been previously stored are still retained when the brain becomes active once again. Therefore, secondary memory must result from some actual alterations of the synapses, either physical or chemical.” — Textbook of Medical Physiology by Arthur C. Guyton (W.B. Saunders Company, Philadelphia, 1986), page 658. “Procedural and declarative memories differ dramatically. They use a different logic (unconscious vs. conscious recall) and they are stored in different areas of the brain. Nevertheless, these two disparate memory processes share several molecular steps and an overall molecular logic. Both are created in at least two stages: one that does not require the synthesis of new proteins and one that does. In both, short-term memory involves covalent modification of preexisting proteins and changes in the strength of preexisting synaptic connections, whereas long-term memory requires the synthesis of new proteins and the growth of new connections. Moreover, both forms of memory use PKA, mitogen-activated protein kinase (MAPK), CREB-1, and CREB-2 signaling pathways to convert short-term to long-term memory. Finally, both forms appear to use morphological changes at synapses to stabilize long-term memory.” — “Synapses and Memory Storage” by Mayford M, Siegelbaum SA, and Kandel ER. Cold Spring Harbor Perspectives in Biology, April 10, 2012, page 10.
- hp50g 14y ago
  Yes but freezing the damn thing fucks the dendrites up completely. The nervous system is dead.

roc 14y ago

If the concept only works when we're relying on full-brain scans and future nano-bots with the capability to reconstruct brain tissue, the freeze/thaw would be completely superfluous. Why not cut out the middle-man? Just do a full brain scan and store the digital data until the nano-bots arrive? Then just recreate brains within stock bodies or some virtual/machine environment? Clinging to the freezing and thawing, when you're forced to concede they won't actually work and then having to invent far superior technologies, but only applying them as a band-aid over the broken technology, looks an awful lot more like someone with a belief grasping for intellectual cover, rather than someone with an intellectual understanding positing solutions.

khafra 14y ago
> Just do a full brain scan and store the digital data until the nano-bots arrive? Because we don't currently have the technology to either scan or store a 3-d scan of your brain in the same resolution you can get by physically perfusing it with antifreeze and dropping it into a bucket of liquid nitrogen.
- roc 14y ago
  But by the time you've physically perfused the brain and frozen it, substantial cell death would have begun. So if we have to freeze until the scanning/storage tech arrives, we'll have a compromised source, at best.
  - khafra 14y ago
    Yes. Whether or not the most substantial damage occurs with apoptosis when oxygen is re-introduced, there will uncontroversially be a lot of damage even in the best case cryonic vitrification. Also uncontroversially, there will be substantially less damage than would occur with cremation or burial. Even the lesser amount of damage may be too much. Cryonics is a bet that it is not.
    - roc 14y ago
      But is there a scientific basis to prefer this bet to, say, death-bed religious conversion?

primitur 14y ago

Science Fiction != Science! (Yet.)

jellicle 14y ago

> Now, I'm rather skeptical of the whole process myself, but the crynoics guys understand biology 101. Actually, they mostly understand Psychology 101, which is that people are willing to pay unlimited amounts of money for the promise of life after death. SEE ALSO: turning lead into gold.

Jach 14y ago
If they really wanted to scam people, there are far better ways than suckering a couple thousand people out of membership dues, and a couple hundred people out of leaving their $30k - $200k (hardly unlimited, especially for software developers!) life insurance payout to a family member.
- afterburner 14y ago
  There's always another way to skin a cat, but you get good at one way and keep at it.
FeepingCreature 14y ago
http://www.alcor.org/cryomyths.html http://www.alcor.org/cryomyths.html > Alcor has no company owners to profit from cryonics, salaries are modest, and the Board of Directors serves without pay.
davidgerard 14y ago
Cryonicists are, generally, painfully sincere. This is not the same as correct, of course. http://rationalwiki.org/wiki/Cryonics http://rationalwiki.org/wiki/Cryonics

snowwrestler 14y ago

Data on a hard drive can be recovered precisely because a typical deletion does not destroy any data--only the addressing bits are erased. If you take a HD and write over half the bits with zeroes, you will not be recovering much useful information from that with digital forensics.