Right now, in three facilities in the US and Russia, there are around 300 people teetering on the cusp of oblivion. They exist in a state of deep cooling called cryopreservation, and entered their chilly slumber after their hearts had stopped beating. Before undergoing true cell death, the tissues of their brains were suspended using an ice-free process called vitrification. All are legally deceased, but if they could they speak, they would likely argue that their remains do not constitute dead bodies at all. Instead, in a sense, they are just unconscious.  No-one knows if it’s possible to revive these people, but more and more of the living seem to believe that uncertainty is better than the alternative. Around 1,250 people who are still legally alive are on cryonics waiting lists, and new facilities are opening in Oregon, Australia and Europe soon.  We have a saying in cryonics: being frozen is the second worst thing that can happen to you – Dennis Kowalski, Cryonics Institute  “We have a saying in cryonics: being frozen is the second worst thing that can happen to you,” says Dennis Kowalski, president of the Cryonics Institute in Michigan, the largest cryonics organization in the world. “There’s no guarantee you’ll be able to be brought back, but there is a guarantee that if you get buried or cremated, you’ll never find out.”  To the uninitiated, cryonics might seem the stuff of “Vanilla Sky,” “Demolition Man,” and other purely science fiction works. But many researchers believe that it is a credible field of inquiry, and cryobiologists are slowly chipping away at the possibility of revival. Most recently, a team succeeded at thawing a previously vitrified rabbit brain. Even after several weeks of storage, the synapses that are thought to be crucial for brain function were intact. The rabbit was still dead, though – the researchers did not attempt to resuscitate the animal afterwards.  While a thawed out rabbit brain does not a fully revitalised person make, some believe that cryogenic revival might someday be as commonplace as treating a case of the flu or mending a broken arm. “This is really not so earth-shattering or philosophically weird as you might think,” says Aubrey de Grey, co-founder and chief science officer at the Sens Research Foundation in California, a non-profit organisation dedicated to changing the way we research and treat age-related ill health. “It’s just medicine – another form of healthcare that helps people who are seriously sick. Once you get your head around that, it’s much less scary.”  They would immediately face the challenge of rebuilding their lives as strangers in a strange land  But assuming cryonics does wind up working, for the newly reborn citizens of the past there would be more to their stories than simply opening their eyes and declaring a happy ending. Instead, they would immediately face the challenge of rebuilding their lives as strangers in a strange land. How that would play out depends on a host of factors, including how long they were gone, what kind of society they returned to, whether they know anyone when they are brought back and in what form they return. Answering these questions is a matter of pure speculation, but experts have spent time turning them over – not the least so some can better prepare for their own potential return.  Much of a cryogenically preserved person’s experience in coming back would depend on the time scale involved. Some enthusiasts are optimistic, using the law of accelerating returns to justify predictions that within the next 30 to 40 years we could develop medical technologies capable of enhancing biological systems, preventing disease and even reverse-engineering aging. If that comes to pass, then there’s a chance that those frozen today would actually be welcomed back by people they knew in their first phase of life – their grown grandchildren, for example.  Lifetime members of the Cryonics Institute can enroll their spouse for half price, and underage children are free  If such advances take longer, on the order of 100 or more years, however, patients would not have such immediate social support in the contemporary world. Some, like Kowalski, are getting around this by simply sticking together: he, his wife and their children have all signed up for cryogenic suspension. Indeed, lifetime members of the Cryonics Institute can enroll their spouse for half price, and underage children are free. “We do that to encourage the family unit to stay together,” Kowalski says.  But even if a cryogenically preserved person was on his or her own, Kowalaski does not think that would necessarily be a deal breaker for eventually attaining happiness. As he puts it: “If you were on an airplane today with all your family and friends and it crashed and you’re the only survivor, would you commit suicide? Or would you go out and put your life back together, and make new family and friends?”  Other cryogenically revived people would be a good starting point for replacing lost connections. Like refugees arriving in a new country, communities of formerly vitrified persons would likely bond around their shared experience and temporal origins.  Where members of those communities would live or how they would support themselves are other unanswered questions. “If they arrive and don’t know much and don’t have any income, they’re going to have to be cared for,” says Daniel Callahan, co-founder and senior research scholar at the Hastings Center, a research institution dedicated to bioethics and health policy. “Who’s going to do that?”  In an attempt to anticipate these needs, the Cryonics Institute invests a fraction of patient fees – currently $28,000 with life insurance – into stocks and bonds. The hope is that future returns can help revived persons get back on their feet, so to speak.  It is possible, however, that money will no longer exist by the time cryonics pays off, and that people will not have to work for a living. A society that has achieved the medical breakthroughs necessary to cure disease and end aging, Kowalski and others believe, may also be one bereft of poverty and material want. In such a scenario, clothing, food and homes, fabricated with 3D printers or some other advanced means, would be abundant and freely available. “It doesn’t make sense that they’d take the time to revive people into some dystopian, backward future,” Kowalski says. “You can’t have the technology to wake people up and not have the technology to do a bunch of other great things, like provide abundance to the population.”  They would be dislocated, alienated and coming to grips with the certainty that everyone they had ever known is lost  Still, even if cryogenically revived persons come back to a more equitable and advanced future, the mental flip-flops required to adjust to that new world would be substantial. Dislocated in time, alienated from society and coming to grips with the certainty that everyone and everything they had ever known is irretrievably lost, they would likely suffer symptoms of intense trauma. And that’s not to mention the fact that some may have to deal with a whole new body because only their head was preserved.  “Even for someone extremely resilient, the need to adapt themselves to a new body, culture and environment seems extremely challenging,” says Jeffry Kauffman, a psychotherapist based outside of Philadelphia. “These people would be forced to ask themselves, ‘Just who am I, really?’”  Others, however, believe that cryonics’ psychological repercussions will prove trivial road bumps for those brought back, thanks to superior forms of future therapy as well as the resilience of the human spirit. “We’re born without consent into a strange world, that’s the human condition,” says Abou Farman, an anthropologist at the New School in New York City. “We tend to adapt to strange situations all the time.”  Kowalski agrees, pointing out that people who move from developing countries to more industrialised ones often do well in their new environment. Likewise, those whose bodies are altered by an accident or in combat are able to carry on.  There’s no doubt though that the intensity of this transition would likely be something completely new to psychologists. Trauma, like depression, can play out in a variety of forms, so the trauma cryonics may trigger could be unlike any iteration we’ve seen before, Kauffman says. “There are a diversity of phenomenologies based in part on differences in what happened, so we can only guess based on other trauma what some aspects of this new one may be.”  There is also the question of how those from the distant past would go about creating relationships with those from the present. Forging genuine connections might prove challenging, Kauffman says, because contemporary persons would likely view antiquated arrivals “as spectacles.”  Although de Grey counters that “people treat other people as oddities all the time,” in this case, the social isolation would likely be more staggering than anything comparable today. “In even 100 years the world can change enormously,” Callahan says. “If you add another 100 years to that, my god, it’s going to be very different indeed. Those from that time would be almost alien creatures.”  These scenarios are still based in the realm of the imaginable, but there is an additional, wildcard option for how all of this could turn out. Should only a person’s consciousness be salvaged and uploaded into some sort of virtual state of being – think Johnny Depp in “Transcendence” – then all bets are off for making predictions on how they would respond. As Kauffman points out, the brain functions in conjunction with sensory organs and other bodily sensations, and even those cut off from their bodies, such as quadriplegic persons, still have self-images. To be bodiless but aware is a ghost-like state completely foreign to what any human has ever experienced before. “What that would be is really just hard to imagine,” Callahan says.  Immortality could also be cause for alarm. An uploaded brain will have beaten death  Immortality could also be cause for alarm. An uploaded brain, in a sense, will have beaten death, which raises basic psychological and philosophical questions. “We can say that death is at the root of consciousness, normative law and human existence,” Kauffman says. “The loss of death is likely to radically alter who or what the being or creature is.”  There’s no guarantee that this ‘being’ would be the same one who first entered into the cryogenic process, either. As de Grey says, the question remains of “whether scanning the brain and uploading it into a different substrate is revival at all, or if you’d be creating a new individual with the same characteristics.”  Regardless of who or what that ghost in the machine turned out to be, programming in a digital suicide option would likely be necessary – just in case the experience proved too overwhelming or oppressive. “I think they’d have to decide in advance what the escape hatch would be if it didn’t work out,” Callahan says. “Is it that the company is authorised to kill you, or are you left to do it yourself?”  Despite the unknowns, some would still be willing to give such an existence a shot. “If the option was complete oblivion and nothingness or uploading my mind into a computer, I’d like to at least try it,” Kowalski says. “It could be pretty cool.”  Join 500,000+ Future fans by liking us on Facebook, or follow us on Twitter, Google+, LinkedIn and Instagram.  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If we could actually cryogenically preserve people for years – or even centuries – what would it feel like for those individuals to wake up?