Cryonics is based upon a working technology, cryogenic freezing of living tissues.
The latest cryonics techiques use M22, an ice crystal growth inhibitor that has been used to preserve small organs and successfully thaw them. More than likely, if you were to rewarm some of the tissues from a cryonics patient frozen today, some of the original cells would still be alive and viable. I don’t know if this particular experiment has been performed, however : there is a reason why cryonics has a bad reputation for pseudoscience.
If you dehydrate a mammalian cell and then add water again, it’s still dead. If you freeze and rewarm, heating and cooling at a rapid enough rate to prevent ice crystal growth, not only is the cell alive, but it can be more viable than newer cells later. Cryogenically frozen sperm or ova from a young person can be more viable than the same substance obtained from the same person later in life.
There are further improvements to cryonics that have not been made because it lacks the funding and resources it deserves.
Better cryoprotectants are more than likely possible.
Better techniques are almost certainly achievable. The method used to preserve a viable rabbit kidney used extremely rapid cooling. Cooling the brain more rapidly might yield better results.
There are potentially revolutionary improvements possible.
The first source I think is a better one : As far as a google search will tell me, this is the only existing human tooth bank in the world. If the teeth weren’t viable it seems unlikely that credible dentists would be attempting the transplants and succeeding.
(I think the technology being used is a lot better indication of it being legitimate than papers or singularity hub articles)
Cryonics is based upon a working technology, cryogenic freezing of living tissues.
Depends on what you mean by “working”. When we successful freeze and revive a mammal, I will concede the point. And its still our best backup option (to not dying). Cryonics has a head start on other possibly techniques, because it was the first conceived and there are people working on it. That doesn’t mean it’s the best or only possibility.
My proposal was for further research, not to start doing it. I admitted we don’t know how to achieve a non-hydrated state capable of recovery, or even if it can be achieved. And this was certainly not intended to be an attack on the work being done on cryonics, just a suggestion that there may be other ways. Speaking of which: DARPA seems to be working on yet another approach. I think as a society we have sufficient resources to pursue various options. I have no horse in this race, I just want to see the finish! :)
More than likely, if you were to rewarm some of the tissues from a cryonics patient frozen today, some of the original cells would still be alive and viable.
EDIT: I should clarify, the kidney was cooled with liquid nitrogen vapor and the lowest temperature it was exposed to was still fifty degrees above that of Liquid Nitrogen. This is important because LN2 temperature is far below the vitrification point of M22, and cooling even a little below T_g causes fracturing.
Yes, but it doesn’t fracture everywhere. Hence, if you rewarmed a tissue that was cryogenically frozen, some cells would probably still be viable. Hence, my hypothesis that if you took samples from a current patient where things were done right, some of the cells would still be alive.
There are fractures like that in existing patients. Note that my hypothesis is that some of the cells would still be viable. I did not say any neurons were viable. I’m merely saying that cryonics is provably better than dehydration or plastination because of this viability factor.
Despite this, IF patients frozen using current techniques can ever be revived, the techniques used will more than likely require a destructive scan of their brains, followed by loading into some kind of hardware or software emulator.
Trying to think of what this might subjectively be like is hard to view rationally. I don’t know if a good emulation or replica is the same person or not : you can make solid arguments either way.
Extremely advanced, better versions of cyronics might eventually reach the point of actually preserving the brain in a manner where reheating brings it back to life and a transplant is possible. However, a destructive scan and upload might still remain the safer choice.
Regardless of how the revivals were actually done in practice, if reproducible and public demonstrations of viability were every performed, I would expect that cryonics would gain widespread prevalence, mainstream acceptance, and become a standard medical procedure.
Why this proposal is a bad one :
Cryonics is based upon a working technology, cryogenic freezing of living tissues.
The latest cryonics techiques use M22, an ice crystal growth inhibitor that has been used to preserve small organs and successfully thaw them. More than likely, if you were to rewarm some of the tissues from a cryonics patient frozen today, some of the original cells would still be alive and viable. I don’t know if this particular experiment has been performed, however : there is a reason why cryonics has a bad reputation for pseudoscience.
If you dehydrate a mammalian cell and then add water again, it’s still dead. If you freeze and rewarm, heating and cooling at a rapid enough rate to prevent ice crystal growth, not only is the cell alive, but it can be more viable than newer cells later. Cryogenically frozen sperm or ova from a young person can be more viable than the same substance obtained from the same person later in life.
There are further improvements to cryonics that have not been made because it lacks the funding and resources it deserves.
Better cryoprotectants are more than likely possible. Better techniques are almost certainly achievable. The method used to preserve a viable rabbit kidney used extremely rapid cooling. Cooling the brain more rapidly might yield better results. There are potentially revolutionary improvements possible.
Allegedly, a Japanese company claims that oscillating magnetic fields prevent orderly crystal growth by water. They have experimental results and succes in preserving human teeth this way. If this method is viable, cryonics could use very large magnets on the human brain and potentially get perfect preservations with demonstrable proof of viability. http://www.teethbank.jp/ http://singularityhub.com/2011/01/23/food-freezing-technology-preserves-human-teeth-organs-next/
The first source I think is a better one : As far as a google search will tell me, this is the only existing human tooth bank in the world. If the teeth weren’t viable it seems unlikely that credible dentists would be attempting the transplants and succeeding. (I think the technology being used is a lot better indication of it being legitimate than papers or singularity hub articles)
Depends on what you mean by “working”. When we successful freeze and revive a mammal, I will concede the point. And its still our best backup option (to not dying). Cryonics has a head start on other possibly techniques, because it was the first conceived and there are people working on it. That doesn’t mean it’s the best or only possibility.
My proposal was for further research, not to start doing it. I admitted we don’t know how to achieve a non-hydrated state capable of recovery, or even if it can be achieved. And this was certainly not intended to be an attack on the work being done on cryonics, just a suggestion that there may be other ways. Speaking of which: DARPA seems to be working on yet another approach. I think as a society we have sufficient resources to pursue various options. I have no horse in this race, I just want to see the finish! :)
Cite please?
Physical and biological aspects of renal vitrification.
Cryopreservation of organs by vitrification: perspectives and recent advances (PDF).
EDIT: I should clarify, the kidney was cooled with liquid nitrogen vapor and the lowest temperature it was exposed to was still fifty degrees above that of Liquid Nitrogen. This is important because LN2 temperature is far below the vitrification point of M22, and cooling even a little below T_g causes fracturing.
Yes, but it doesn’t fracture everywhere. Hence, if you rewarmed a tissue that was cryogenically frozen, some cells would probably still be viable. Hence, my hypothesis that if you took samples from a current patient where things were done right, some of the cells would still be alive.
A related article : http://www.nature.com/ncomms/journal/v3/n6/full/ncomms1890.html?WT.mc_id=FBK_NCOMMS
What about a fracture that severs the brain in several pieces?
There are fractures like that in existing patients. Note that my hypothesis is that some of the cells would still be viable. I did not say any neurons were viable. I’m merely saying that cryonics is provably better than dehydration or plastination because of this viability factor.
Despite this, IF patients frozen using current techniques can ever be revived, the techniques used will more than likely require a destructive scan of their brains, followed by loading into some kind of hardware or software emulator.
Trying to think of what this might subjectively be like is hard to view rationally. I don’t know if a good emulation or replica is the same person or not : you can make solid arguments either way.
Extremely advanced, better versions of cyronics might eventually reach the point of actually preserving the brain in a manner where reheating brings it back to life and a transplant is possible. However, a destructive scan and upload might still remain the safer choice.
Regardless of how the revivals were actually done in practice, if reproducible and public demonstrations of viability were every performed, I would expect that cryonics would gain widespread prevalence, mainstream acceptance, and become a standard medical procedure.