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The idea of placing people in “suspended animation” – “cold storage” -- is a science fiction standard. Many authors have used it as a fictional device to explain how people will travel long distances through interstellar space without getting any older. The star-voyager gets on the spaceship, locks himself in the freezing chamber – and is automatically defrosted a million years later, not one second older. The essential scientific basis for the concept is a simple one: freezing slows molecular motions to a crawl, essentially ceasing cellular processes, including aging and metabolism.
Serious thinking about cryonics – the technical term for placing people into suspended animation by freezing them – began in the 1960’s. At this point the technology for freezing people in liquid nitrogen was just barely becoming economically feasible. Futurists began to consider the possibility of freezing themselves immediately after their death, to preserve their body for eventual restoration by future scientists with advanced medical techniques. Sure, you may have died of incurable cancer in 1975, but what if the cure for your type of cancer is found in 2053? Then you can just be defrosted, given the cure, and jolted back to life by futuristic medical magic.
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The weak point of this plan, in the 60’s, was that no one had a very clear idea about the revival part. There were no known technologies for defrosting people and curing their diseases – the best cryonics advocates could offer was an emphatic waving of the hands and a quick nod to “future technology.” But even so, the idea was visionary. After all, technical details aside, it does seem awfully likely that, 1000 years from now or so, the technology will exist to revive a frozen corpse. Look how far technology has come in the last 1000 years! Or if not 1000 years, what about 10,000? This isn’t a concept whose plausibility requires a sophisticated scientific and engineering basis, or a fanatically optimistic faith in technological acceleration.
And now, 30 years down the line, the idea looks even more reasonabe. Biologists are moving toward an understanding of cell death, and it seems quite reasonable that in a few decades – for sure a few centuries -- the process may be haltable or reversible. The concept of nanotechnology has become commonplace: machines are getting smaller and smaller, and serious scientists envision swarms of microscopic robots zooming through the body, delivering medicine or repairing damaged cells. No, we can’t yet defrost and repair a frozen corpse. But we now see clear scientific pathways that are likely to lead to this ability, given time.
The picture gets clearer and clearer each year: Science may not defeat aging within our lifetimes, but it may well be possible for us to avoid permanently dying of old age by preserving our bodies shortly after death, and letting future scientists revive us. Furthermore, dozens of forward-thinking people have already availed themselves of this opportunity, and are waiting in cold storage for the next iteration of their lives.
Until recently, cryonic preservation meant freezing in liquid nitrogen. But this is a very harsh process. Freezing a human brain or body in liquid nitrogen does preserve its basic cellular structure: assuming self and memory are contained in the brain’s neurons and synapses, it’s clear they are preserved through the freezing process. However, the formation of ice crystals in the body during freezing causes so much cell damage that no simple defrosting and resurrection of a patient simply frozen in liquid nitrogen will ever be possible. Advanced nanotechnology of some sort will be necessary to bring a frozen body back to life.
The scene shouldn’t be painted too darkly: freezing in liquid nitrogen still provides a good way to elude death, vastly better than any previously known alternative. Swarms of future nanobots, zooming through the body repairing damaged cells, will easily possess the ability bring a frozen body back to life and health. Or, advanced scanning technology may simply read the mind out of a frozen brain, and embed it in a computer or an android or a newly synthesized human body.
But these days, we can do better than mere freezing. We have vitrification, a related but significantly different method of stopping biological time. Vitrification converts biological tissue into a strange kind of low-temperature glass that is totally free of ice crystals. Gregory Fahy created the technology a couple decades ago as a technique for preserving organs intended for transplantation; and in the intervening years it’s come impressively far. So far, embryos, ova, ovaries, skin, pancreatic islets and blood vessels have been vitrified and then de-vitrified for transplant. Successful de-vitrification of whole organs like kidneys livers, hearts and lungs isn’t too far off.
Like many technologies, vitrification is inspired by the wonders of nature. There are frogs that can spend days or weeks in freezing conditions, with up to 65 percent of their total body water frozen solid. This is achieved through the distribution of special “antifreeze” chemicals through the bloodstream – “cryoprotectant” chemicals that reduce ice formation using one of a number of mechanisms. Some amphibians manufacture the cryoprotectant glycerol in their livers. Arctic frogs have a special form of insulin that accelerates the absorption of glucose, another cryoprotectant, into their cells. A good cryoprotectant makes water freeze smoothly and purely like glass, with no crystal formation. Cryoprotectants work best, especially in non-viscous liquids like water, if the freezing happens very fast, what’s called “flash-freezing.”
The biggest problem in organ-vitrification research so far has been not freezing but defrosting. If the reheating of the organ isn’t fast enough, damaging ice crystals can form during this phase, rendering the delicacy of the cryoprotected freezing process irrelevant. What’s needed to circumvent this problem is, basically, a very fast heater –it’s suspected that radiofrequency rewarming – somewhat similar to microwave heating -- may do the trick. The process may also be aided by chemicals that prevent ice formation through methods besides straightforward cryoprotection.
“Carrier solutions” like glutathione can reduce the amount of cryoprotectant needed to cause vitrification. And ice-blockers like threonine and serine prevent the formation of ice-crystal nuclei, by bonding to nascent ice-crystals in appropriate ways. freeze proteins that inhibit c-axis growth. The creation of an appropriate chemical cocktail to promote successful vitrification and de-vitrification is a subtle matter, but one that scientists are hard at work on. In large part, it’s the recent development of sophisticated ice-blockers that has made vitrification newly plausible for cryonics – this has drastically reduced the amount of cryoprotectant needed to make vitrification work.
The biggest problem vitrification faces so far is that to vitrify a whole organ or body requires a lot of cryoprotectant, and all known cryoprotectants are highly toxic. This is a bigger problem for contemporary organ transplant work than for long-term cryonics applications, however, because it’s very likely future science will discover ways to palliate the toxic effects of cryoprotectants. Palliating poisoning has got to be vastly easier than repairing the ice crystal damage done by straightforward freezing, and should be achievable via advanced pharmacology alone.
Finally, vitrified systems have a nasty habit of cracking to pieces if they’re cooled to liquid nitrogen temperature (-196°C). However, a long-term storage temperature of -130°C to -150°C seems to work fine. In fact, bodies simply frozen in liquid nitrogen without cryoprotectant often crack too, but given the severity of garden variety ice crystal damage, no one ever particularly worried about this cracking. Now, with vitrification, cryonicists can seek perfection. Vitrify the body, then when the ill that killed it becomes curable, devitrify it, pumping in an antidote to the cryprotectant’s toxic effects. “ Good morning, what year is it? What? 3010 already? When I died it was 2015….”
All in all, while we don’t yet have a viable way of freezing and defrosting organs let along organisms, it’s clear that science is progressing in the right direction. The steady, incremental advancement of cryobiology will get us where we need to go.
Ok, you’re convinced now – but how do you do it, in practice? Do you have to build a vitrifier in your basement, and tell your friends and family, should they ever find you stiff and cold, to jam you inside?
Thankfully, no. There are a handful of organizations providing cryonics services to interested individuals – and at least one of them, Alcor Life Extension Foundation, appears to be truly serious and responsible. They have close to 40 “patients” in cold storage right now, awaiting the technological advances necessary for their resuscitation. Their first patient was placed in liquid nitrogen in 1967. When you sign up you’re given an Alcor bracelet or necklace, stating that if your body is found dead, Alcor should be telephoned at once so they can come fetch it before it decomposes.
To have your whole body preserved and cared for by Alcor, the current cost is $120,000, of which about $30,000 covers the direct cost of transporting your body to Alcor and freezing it, and the remainder goes into a fund called the Patient Care Trust. On the other hand, to be a “neuro patient” and have only your brain preserved costs about $50,000, a relative bargain. Right now, vitrification is only available for “neuro patients,” but this limitation is purely a matter of cost – Alcor can’t yet afford a system capable of preserving whole vitrified bodies – and will be overcome in a few years time.
Most Alcor members pay the costs of cryopreservation by taking out a life insurance policy payable to Alcor. A few hundred bucks a year is what it comes out to, if you take out the policy when you’re young. Not a bad price for a chance at radically extended life. The money in the Patient Trust Fund is primarily earmarked for long-term care and resuscitation. In some years, however, Alcor has been forced to spend a great deal of cash on legal battles, due to the difficulty that many conservative-minded individuals have with the very idea of cryonic preservation.
The Alcor management are to be congratulated for their maturity and responsibility. In addition to solving the technical problems of deploying cryonic technology under real-world conditions, they have taken on the very serious task of creating an organizational framework plausibly capable of surviving for centuries or millennia. The difficulties associated with the latter are illustrated by the fate of Cryocare, an organization that split off from Alcor in 1993.
Cryocare management was experienced, including some Alcor very-old-timers. They had a firm handle on the technical side of cryonics, and took 2 patients under their care. But their organizational model was not robust. The founders viewed Cryocare as a kind of meta-organization, which would subcontract the various tasks involved in cryonic life extension to other firms. In this way, it was felt, the forces of free market competition would allow Cryocare to continually provide its patients with the best quality services in every aspect. In a world where cryonics was widespread, this approach might well make sense. But if you go to the Cryocare website now, you find the following message:
CryoCare Foundation was established in 1993 to provide state-of-the-art human cryopreservation with assistance from two separate, independent businesses: BioPreservation, which provided our remote standby, transport, perfusion, and cooldown capability, and CryoSpan, which managed the long- term maintenance of patients at liquid-nitrogen temperature.
Ultimately we hoped that growth in cryonics would encourage the formation of additional service providers. We envisaged a future in which our members would benefit as BioPreservation and CryoSpan found themselves in a free market, bidding against competitors.
Unfortunately, we overestimated the potential growth and profitability of cryonics. Also we underestimated the tendency of volunteers and enthusiasts to burn out, especially in a high-stress occupation such as remote standby work. BioPreservation opted not to renew its contract with us in 1999, and no longer provides any cryonics services. CryoSpan still exists, but its majority shareholder wants to wind down the company and transfer the patients elsewhere.
Consequently, CryoCare now finds itself without any service providers.
We received ample advance warning of this situation, and attempted to find other ways to maintain service. These attempts were unsuccessful. Consequently, in 1999 we notified our members that we could not continue to provide cryonics coverage.
Their two patients were transferred to Alcor. No harm done. But thank goodness for Alcor.
Cryonics sounds science-fictional at first – but like a lot of other wild-sounding technological ideas, when you think about it carefully, it makes a surpassing amount of sense. From my point of view, the surprising thing is that so few people have taken advantage of the possible escape route offered by cryonics. The financial cost is not so high, and the potential benefits – centuries or millennia of extra life – are pretty astounding.
Admittedly, only individuals in the developed world can afford such a thing; and the majority of people even in the developed world are religious and adhere to one of the many contemporary belief systems promising a supernatural afterlife. But even so, there are tens of millions of non-religious folks in the developed world – people who believe that once they’re dead, they’re gone, period. And there are millions of individuals in this category who have died since Alcor was founded in 1969. Yet only 40 or so people lie frozen in Alcor’s chambers.
To explain the peculiar smallness of this number, it is tempting to invoke Freudian psychology and the notion of the death wish. At very least, setting aside any issues to do with the rationality of religious belief systems, the situation indicates an inability on the part of most non-religious modern humans to think rationally about the subject of their own death. Death is something most of us would prefer not to ponder or concretely confront – and yet, the irony is, openly confronting the reality of the body’s death can allow us to take rational steps to avoid it.
Upon careful analysis, the biggest risks associated with cryonics are not scientific but rather social in nature. Let’s say you’re vitrified in 2020, and it’s 500 or 1000 years until technology advances to the point where you can be defrosted and brought back to life. I’m hoping that by the end of the 21’st century pharmacology and nanotechnology will have essentially defeated human mortality -- but even a non-techno-optimist has to got to admit that a lot of progress is going to happen in the next thousand years. But what’s the chance that Alcor, or any other organization that’s vitrified you, is still going to be around in 3020? True, there are precedents for organizations lasting almost this long – Cambridge University was founded in the 1200’s and it’s still going strong. But a lot can happen in 1000 years – revolutions, nuclear holocausts, alien invasions, financial crises, catastrophic interventions by conservative-minded government officials, months-long power outages during which all the corpsicles in storage defrost and rot….
But still -- the risks notwithstanding -- the odds of long-term survival via cryonic preservation would appear to drastically beat the odds associated with any of the alternatives: cremation, burial and ensuing decomposition, et cetera. For a few hundred bucks a year, which would you prefer? A few extra features on your car, or a chance at living a thousand or a million years, or perhaps becoming a superintelligent AI being and transcending the spacetime continuum altogether? I truly believe that, a few hundred years from now, our descendants are going to look back and be thoroughly baffled that a project so obvious as cryonic life preservation took so long to get off the ground.
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